3,539 results on '"Fertilité du sol"'
Search Results
252. Quantifying nitrogen losses in oil palm plantations: Models and challenges
- Author
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Pardon, Lénaïc, Bessou, Cécile, Saint-Geours, Nathalie, Gabrielle, Benoît, Khasanah, Ni'matul, Caliman, Jean-Pierre, Nelson, Paul N., Pardon, Lénaïc, Bessou, Cécile, Saint-Geours, Nathalie, Gabrielle, Benoît, Khasanah, Ni'matul, Caliman, Jean-Pierre, and Nelson, Paul N.
- Abstract
Oil palm is the most rapidly expanding tropical perennial crop. Its cultivation raises environmental concerns, notably related to the use of nitrogen (N) fertilisers and the associated pollution and greenhouse gas emissions. While numerous and diverse models exist to estimate N losses from agriculture, very few are currently available for tropical perennial crops. Moreover, there is a lack of critical analysis of their performance in the specific context of tropical perennial cropping systems. We assessed the capacity of 11 models and 29 sub-models to estimate N losses in a typical oil palm plantation over a 25-year growth cycle, through leaching and runoff, and emissions of NH3, N2, N2O, and NOx. Estimates of total N losses were very variable, ranging from 21 to 139 kg N ha−1 yr−1. On average, 31 % of the losses occurred during the first 3 years of the cycle. Nitrate leaching accounted for about 80 % of the losses. A comprehensive Morris sensitivity analysis showed the most influential variables to be soil clay content, rooting depth, and oil palm N uptake. We also compared model estimates with published field measurements. Many challenges remain in modelling processes related to the peculiarities of perennial tropical crop systems such as oil palm more accurately.
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- 2016
253. Intensifier la culture du maïs pour améliorer la sécurité alimentaire : le producteur du Nord Cameroun y a-t-il intérêt ?
- Author
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Guibert, Hervé, Kenne Kueteyim, Pinardel, Olina Bassala, Jean-Paul, M'Biandoun, Mathurin, Guibert, Hervé, Kenne Kueteyim, Pinardel, Olina Bassala, Jean-Paul, and M'Biandoun, Mathurin
- Abstract
L'intensification de la culture du maïs, majoritairement destinée à l'autoconsommation rurale et à l'approvisionnement des villes, est une opportunité pour améliorer la sécurité alimentaire des régions septentrionales du Cameroun et limiter la pression foncière. Pour étudier sa faisabilité, trois niveaux d'intensification ont été testés en 2013 dans 32 champs de maïs à proximité de Garoua dans la région du Nord, 16 considérés comme fertiles par les producteurs et 16 comme dégradés : (i) la conduite habituelle par le producteur (CP), (ii) un premier niveau d'intensification (NI1) correspondant aux recommandations actuelles de la vulgarisation agricole et (iii) un second niveau d'intensification (NI2) avec, par rapport à NI1, un renforcement des amendements, un traitement de semences amélioré, de meilleures densité et contrôle des mauvaises herbes. CP et NI1 ont des rendements proches dans les deux villages : en moyenne 2,3 et 1,3 t.ha–1, respectivement sur parcelles fertiles et dégradées, indiquant que les producteurs suivent assez bien les recommandations de la vulgarisation agricole. Les rendements des parcelles sous NI2 sont significativement supérieurs aux autres, en moyenne de 1 t.ha–1 sur le site de Ngong où la pluviosité est la plus faible et 1,5 t.ha–1 sur le site de Gashiga. Curieusement, le gain de rendement apporté par NI2 est identique sur parcelles fertiles comme dégradées, indiquant que la dégradation de ces dernières, avérée par leur moindre production, permet néanmoins une réponse à une intensification accrue. Malgré ces résultats, la profitabilité d'une intensification accrue au prix actuel du maïs, notamment celui ayant cours au moment de la récolte, n'est pas établie. Un meilleur prix rendrait profitable l'intensification et la production accrues de la culture du maïs dans ces régions, comme le pratiquent déjà en partie certaines exploitations dites émergentes, qui maîtrisent mieux la commercialisation de leurs productions.
- Published
- 2016
254. Mieux évaluer et accompagner l'innovation agricole en Afrique. Leçons d'une analyse transversale de 13 cas d'études
- Author
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Triomphe, Bernard, Floquet, Anne, Letty, Brigid, Kamau, Geoffrey, Almekinders, Cornelia, Waters-Bayer, Ann, Triomphe, Bernard, Floquet, Anne, Letty, Brigid, Kamau, Geoffrey, Almekinders, Cornelia, and Waters-Bayer, Ann
- Abstract
Cet article présente les résultats clés tirés de l'analyse transversale de 13 expériences d'innovation agricole menées au Bénin, au Kenya et en Afrique du Sud. L'évaluation a utilisé un cadre analytique commun inspiré de l'approche systèmes d'innovation pour comprendre comment l'innovation a évolué au fil du temps via les interactions entre différents acteurs et sous l'effet d'éléments déclencheurs et moteurs internes et externes. Menée de manière participative par des équipes mixtes de chercheurs, d'étudiants et d'acteurs locaux, elle s'est fondée sur des entretiens semi-structurés, des focus groupes et des ateliers multi-acteurs. Les 13 cas portent sur une diversité d'expériences en termes de domaines, types, échelles, durée, initiateurs de l'innovation et acteurs concernés. Les résultats montrent la multiplicité et le rôle des acteurs impliqués dans l'innovation, la nature des déclencheurs et moteurs de l'innovation. Ils montrent aussi l'importance de la prise en compte du temps long pour comprendre les processus d'innovation. Ils montrent enfin l'influence tant positive que parfois problématique des interventions externes sur les processus d'innovation, et en particulier les difficultés à institutionnaliser l'innovation au-delà des interventions ou à interagir avec les dynamiques locales d'innovation. L'article propose diverses voies pour améliorer tant l'évaluation que l'accompagnement des processus d'innovation. Cela concerne en particulier la conception et le financement des interventions externes. Cela concerne aussi l'acquisition des compétences et capacités indispensables à la mise en oeuvre dans la durée d'approches ouvertes et souples de conception, renforçant chaque fois que possible les initiatives existantes des acteurs locaux.
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- 2016
255. Rhizobial characterization in revegetated areas after bauxite mining
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Borges, Wardsson Lustrino, Prin, Yves, Ducousso, Marc, Le Roux, Christine, De Faria, Sergio Miana, Borges, Wardsson Lustrino, Prin, Yves, Ducousso, Marc, Le Roux, Christine, and De Faria, Sergio Miana
- Abstract
Little is known regarding how the increased diversity of nitrogen-fixing bacteria contributes to the productivity and diversity of plants in complex communities. However, some authors have shown that the presence of a diverse group of nodulating bacteria is required for different plant species to coexist. A better understanding of the plant symbiotic organism diversity role in natural ecosystems can be extremely useful to define recovery strategies of environments that were degraded by human activities. This study used ARDRA, BOX-PCR fingerprinting and sequencing of the 16S rDNA gene to assess the diversity of root nodule nitrogen-fixing bacteria in former bauxite mining areas that were replanted in 1981, 1985, 1993, 1998, 2004 and 2006 and in a native forest. Among the 12 isolates for which the 16S rDNA gene was partially sequenced, eight, three and one isolate(s) presented similarity with sequences of the genera Bradyrhizobium, Rhizobium and Mesorhizobium, respectively. The richness, Shannon and evenness indices were the highest in the area that was replanted the earliest (1981) and the lowest in the area that was replanted most recently (2006).
- Published
- 2016
256. Dry matter production, nutrient cycled and removed, and soil fertility changes in yam-based cropping systems with herbaceous legumes in the Guinea-Sudan zone of Benin
- Author
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Maliki, Raphiou, Sinsin, Brice Augustin, Floquet, Anne, Cornet, Denis, Malézieux, Eric, Vernier, Philippe, Maliki, Raphiou, Sinsin, Brice Augustin, Floquet, Anne, Cornet, Denis, Malézieux, Eric, and Vernier, Philippe
- Abstract
Traditional yam-based cropping systems (shifting cultivation, slash-and-burn, and short fallow) often result in deforestation and soil nutrient depletion. The objective of this study was to determine the impact of yam-based systems with herbaceous legumes on dry matter (DM) production (tubers, shoots), nutrients removed and recycled, and the soil fertility changes. We compared smallholders' traditional systems (1-year fallow of Andropogon gayanus-yam rotation, maize-yam rotation) with yam-based systems integrated herbaceous legumes (Aeschynomene histrix/maize intercropping-yam rotation, Mucuna pruriens/maize intercropping-yam rotation). The experiment was conducted during the 2002 and 2004 cropping seasons with 32 farmers, eight in each site. For each of them, a randomized complete block design with four treatments and four replicates was carried out using a partial nested model with five factors: Year, Replicate, Farmer, Site, and Treatment. Analysis of variance (ANOVA) using the general linear model (GLM) procedure was applied to the dry matter (DM) production (tubers, shoots), nutrient contribution to the systems, and soil properties at depths 0–10 and 10–20 cm. DM removed and recycled, total N, P, and K recycled or removed, and soil chemical properties (SOM, N, P, K, and pH water) were significantly improved on yam-based systems with legumes in comparison with traditional systems.
- Published
- 2016
257. Communicating complexity: Integrated assessment of trade-offs concerning soil fertility management within African farming systems to support innovation and development
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Shamie Zingore, Pablo Tittonell, F. Baijukya, Paul Mapfumo, Samuel Adjei-Nsiah, A. Mwijage, D. Nwaga, N. de Ridder, Edwin C. Rowe, M. Misiko, Regis Chikowo, M.T. van Wijk, M. Mwale, Ken E. Giller, S. Karanja, W.J. van der Burg, Mario Herrero, James B. Kungu, Mariana C. Rufino, E. Yeboah, C.K. Kaizzi, O. Sanogo, Marc Corbeels, Jo Smith, Bernard Vanlauwe, and Cesare Pacini
- Subjects
Resource (biology) ,Integrated farming ,Emerging technologies ,cycling efficiencies ,smallholder farms ,F08 - Systèmes et modes de culture ,Population ,western kenya ,resource-allocation ,nutrient use efficiencies ,Fertilité du sol ,land-use ,southern mali ,education ,Agroecology ,Applied Ecology ,education.field_of_study ,Land use ,U10 - Informatique, mathématiques et statistiques ,business.industry ,Environmental resource management ,P35 - Fertilité du sol ,Toegepaste Ecologie ,dynamics ,PE&RC ,exploring diversity ,Plant Production Systems ,Agriculture ,Plantaardige Productiesystemen ,Animal Science and Zoology ,crop-livestock systems ,Business ,Soil conservation ,Agronomy and Crop Science - Abstract
African farming systems are highly heterogeneous: between agroecological and socioeconomic environments, in the wide variability in farmers’ resource endowments and in farm management. This means that single solutions (or ‘silver bullets’) for improving farm productivity do not exist. Yet to date few approaches to understand constraints and explore options for change have tackled the bewildering complexity of African farming systems. In this paper we describe the Nutrient Use in Animal and Cropping systems – Efficiencies and Scales (NUANCES) framework. NUANCES offers a structured approach to unravel and understand the complexity of African farming to identify what we term ‘best-fit’ technologies – technologies targeted to specific types of farmers and to specific niches within their farms. The NUANCES framework is not ‘just another computer model’! We combine the tools of systems analysis and experimentation, detailed field observations and surveys, incorporate expert knowledge (local knowledge and results of research), generate databases, and apply simulation models to analyse performance of farms, and the impacts of introducing new technologies. We have analysed and described complexity of farming systems, their external drivers and some of the mechanisms that result in (in)efficient use of scarce resources. Studying sites across sub-Saharan Africa has provided insights in the trajectories of change in farming systems in response to population growth, economic conditions and climate variability (cycles of drier and wetter years) and climate change. In regions where human population is dense and land scarce, farm typologies have proven useful to target technologies between farmers of different production objectives and resource endowment (notably in terms of land, labour and capacity for investment). In such regions we could categorise types of fields on the basis of their responsiveness to soil improving technologies along soil fertility gradients, relying on local indicators to differentiate those that may be managed through ‘maintenance fertilization’ from fields that are highly-responsive to fertilizers and fields that require rehabilitation before yields can improved. Where human population pressure on the land is less intense, farm and field types are harder to discern, without clear patterns. Nutrient cycling through livestock is in principle not efficient for increasing food production due to increased nutrient losses, but is attractive for farmers due to the multiple functions of livestock. We identified trade-offs between income generation, soil conservation and community agreements through optimising concurrent objectives at farm and village levels. These examples show that future analyses must focus at farm and farming system level and not at the level of individual fields to achieve appropriate targeting of technologies – both between locations and between farms at any given location. The approach for integrated assessment described here can be used ex ante to explore the potential of best-fit technologies and the ways they can be best combined at farm level. The dynamic and integrated nature of the framework allows the impact of changes in external drivers such as climate change or development policy to be analysed. Fundamental questions for integrated analysis relate to the site-specific knowledge and the simplification of processes required to integrate and move from one level to the next. Keywords: Crop–livestock systems; Soil fertility; Smallholders; Farm types; Simulation modelling
- Published
- 2011
258. How do we evaluate an innovative process? Case of the quantitative and qualitative improvement of organic manure in the field
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M. Blanchard, M. Koutou, E. Vall, and S. Bognini
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Amendement organique ,Fertilité du sol ,Evaluation de l’impact ex post ,Engrais ,Innovation ,Afrique occidentale ,SF1-1100 ,Animal culture - Abstract
Soil fertility in West Africa is under high anthropogenic pressure caused by the increasing population, extension of cultivated areas and abandonment of fallows. Through a participatory action research approach, the Fertipartenaires project proposed to design with farmers innovations on the use of organic manure, in three steps: increase the production capacity of organic manure by building pits, improve production quality, and integrate its application in the field. How do we assess an innovative process made up of several stages that cover different space and time scales? How do we include this assessment in a participatory approach? A participatory assessment method in three steps is proposed: (1) assessment of the direct effect of innovation (partial assessment), (2) analysis of economic, sociological and ecological indirect consequences of the innovation, and (3) analysis of innovation dynamics (adoption, dissemination, and redefinition). Two models of organic manure production have been tested: a manure pit built on the concession and a compost pit built at the edge of the field. The analysis of the direct effects of compost production shows that it is economically more advantageous than manure with its higher opportunity costs. However, the two production models are complementary and they each have a positive balance. The method used helps to assess the direct effects of innovation on the economic impact of organic manure production. It helps start discussions with farmers around the simplified illustration of the direct effects of innovation. It should however be completed by the analysis of indirect consequences and innovation dynamics so as to take into account the dimensions that were not included in the partial assessments.
- Published
- 2011
259. Managing soil fertility diversity to enhance resource use efficiencies in smallholder farming systems: a case from Murewa District, Zimbabwe
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Shamie Zingore, Ken E. Giller, Marc Corbeels, M.T. van Wijk, and Pablo Tittonell
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gradients ,Crop residue ,western kenya ,Soil Science ,engineering.material ,Zea mays ,Petite exploitation agricole ,scale ,Matière organique du sol ,nutrient use efficiencies ,Fertilité du sol ,balances ,organic-matter ,Productivity ,U10 - Informatique, mathématiques et statistiques ,variability ,Intensive farming ,Agroforestry ,business.industry ,P35 - Fertilité du sol ,Soil carbon ,PE&RC ,field ,Manure ,Plant Production Systems ,Agronomy ,Agroécosystème ,Agriculture ,Plantaardige Productiesystemen ,strategies ,engineering ,Environmental science ,Fertilizer ,Soil fertility ,business ,Agronomy and Crop Science ,management ,F04 - Fertilisation - Abstract
Smallholder farms in sub-Saharan African exhibit substantial heterogeneity in soil fertility, and nutrient resource allocation strategies that address this variability are required to increase nutrient use efficiencies. We applied the Field-scale resource Interactions, use Efficiencies and Long-term soil fertility Development (FIELD) model to explore consequences of various manure and fertilizer application strategies on crop productivity and soil organic carbon (SOC) dynamics on farms varying in resource endowment in a case study village in Murewa District, Zimbabwe. FIELD simulated a rapid decline in SOC and maize yields when native woodlands were cleared for maize cultivation without fertilizer inputs coupled with removal of crop residues. Applications of 10 t manure ha-1 year-1 for 10 years were required to restore maize productivity to the yields attainable under native woodland. Long-term application of manure at 5 and 3 t ha-1 resulted in SOC contents comparable to zones of high and medium soil fertility observed on farms of wealthy cattle owners. Targeting manure application to restore SOC to 50-60% of contents under native woodlands was sufficient to increase productivity to 90% of attainable yields. Short-term increases in crop productivity achieved by reallocating manure to less fertile fields were short-lived on sandy soils. Preventing degradation of the soils under intensive cultivation is difficult, particularly in low input farming systems, and attention should be paid to judicious use of the limited nutrient resources to maintain a degree of soil fertility that supports good crop response to fertilizer application.
- Published
- 2010
260. The diversity of rural livelihoods and their influence on soil fertility in agricultural systems of East Africa – A typology of smallholder farms
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Richard Coe, Anne Muriuki, Bernard Vanlauwe, Daniel N. Mugendi, Keith D. Shepherd, Jeremiah M. Okeyo, Pablo Tittonell, K.C. Kaizzi, and Louis V. Verchot
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Exploitation agricole familiale ,Endowment ,Cash crop ,Farm income ,western kenya ,Petite exploitation agricole ,Soil management ,Agricultural science ,Fertilité du sol ,Niveau de vie ,variability ,Agroforestry ,business.industry ,P35 - Fertilité du sol ,dynamics ,PE&RC ,exploring diversity ,Classification ,Livelihood ,E51 - Population rurale ,welfare ,Geography ,Plant Production Systems ,Agriculture ,Plantaardige Productiesystemen ,Système de culture ,Animal Science and Zoology ,Livestock ,heterogeneity ,Soil fertility ,business ,Agronomy and Crop Science ,management - Abstract
Technological interventions to address the problem of poor productivity of smallholder agricultural systems must be designed to target socially diverse and spatially heterogeneous farms and farming systems. This paper proposes a categorisation of household diversity based on a functional typology of livelihood strategies, and analyses the influence of such diversity on current soil fertility status and spatial variability on a sample of 250 randomly selected farms from six districts of Kenya and Uganda. In spite of the agro-ecological and socio-economic diversity observed across the region (e.g. 4 months year_1 of food self-sufficiency in Vihiga, Kenya vs. 10 in Tororo, Uganda) consistent patterns of variability were also observed. For example, all the households with less than 3 months year_1 of food self-sufficiency had a land:labour ratio (LLR) < 1, and all those with LLR > 1 produced enough food to cover their diet for at least 5 months. Households with LLR < 1 were also those who generated more than 50% of their total income outside the farm. Dependence on off/non-farm income was one of the main factors associated with household diversity. Based on indicators of resource endowment and income strategies and using principal component analysis, farmers' rankings and cluster analysis the 250 households surveyed were grouped into five farm types: (1) Farms that rely mainly on permanent off-farm employment (from 10 to 28% of the farmers interviewed, according to site); (2) larger, wealthier farms growing cash crops (8-20%); (3) medium resource endowment, food self-sufficient farms (20-38%); (4) medium to low resource endowment relying partly on non-farm activities (18-30%); and (5) poor households with family members employed locally as agricultural labourers by wealthier farmers (13-25%). Due to differential soil management over long periods of time, and to ample diversity in resource endowments (land, livestock, labour) and access to cash, the five farm types exhibited different soil carbon and nutrient stocks (e.g. Type 2 farms had average C, N, P and K stocks that were 2-3 times larger than for Types 4 or 5). In general, soil spatial variability was larger in farms (and sites) with poorer soils and smaller in farms owning livestock. The five farm types identified may be seen as domains to target technological innovations and/or development efforts.
- Published
- 2010
261. Le coton biologique au Paraguay. 2. Production et contraintes agronomiques
- Author
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Silvie, Pierre, Martin, J., Debru, J., and Vaissayre, M.
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RENDEMENT ,lcsh:Biotechnology ,yields ,PRODUCTION AGRICOLE ,cropping system ,F01 - Culture des plantes ,farm-made fertilizers and pesticides ,lcsh:TP248.13-248.65 ,AGRICULTURE BIOLOGIQUE ,COTON ,lcsh:Environmental sciences ,lcsh:GE1-350 ,Gossypium ,FERTILITE DU SOL ,soil fertility ,SYSTEME DE CULTURE ,LUTTE ANTIINSECTE ,FILIERE ECONOMIQUE ,Organic cotton ,pest management ,Paraguay ,INTRANT AGRICOLE ,ANIMAL NUISIBLE ,production ,Anthonomus grandis - Abstract
En culture cotonnière biologique, la fertilité des sols et la maitrise des bioagresseurs sont les deux contraintes agronomiques majeures. Au Paraguay, la filière cotonnière biologique se développe depuis 2003. Le présent article fait suite à une étude exploratoire qui a été réalisée en 2008 dans le but d'appréhender la construction de la filière et d'identifier des contraintes économiques et organisationnelles. Ce deuxième article rapporte une analyse de la production et des contraintes agronomiques. L'étude a été effectuée en période de récolte du coton sous la forme d'entretiens avec les acteurs institutionnels et les producteurs. Avec plus de 200 tonnes de coton-graine produites dès 2006-2007, le Paraguay est devenu le deuxième producteur de coton biologique sud-américain derrière le Pérou. En 2007-2008, le rendement moyen enregistré de 492 kg.ha-1 de coton-graine a été sous-estimé en raison d'importantes fuites de production vers la filière conventionnelle. Les pratiques de gestion de la fertilité des sols, de fertilisation de la culture et de lutte contre les ravageurs, notamment contre le charançon des capsules Anthonomus grandis, s'inscrivent dans un système de culture avec rotation sans brûlis, avec fumier de ferme, cultures d'engrais verts et des intrants fermiers, diversement préparés et appliqués. Leur efficacité, jugée bonne par les prescripteurs et les utilisateurs, n'a pas été formellement étudiée. Dans tous les cas, des recherches sont nécessaires pour identifier les processus biologiques mis en oeuvre lorsqu'ils sont peu ou pas connus, pour appréhender qualitativement et quantitativement la variabilité des pratiques paysannes et enfin pour intégrer leurs effets à différentes échelles d'espace et de temps.
- Published
- 2010
262. Conservation agriculture and smallholder farming in Africa: The heretics’ view
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Ernst Witter, Pablo Tittonell, Marc Corbeels, Ken E. Giller, and Sustainable Agriculture and Natural Resource Management (SANREM) Knowledgebase
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Carbon sequestration ,Résidu de récolte ,Crop residues ,Mulch ,Natural resource economics ,Non-travail du sol ,agriculture alternative ,F01 - Culture des plantes ,Main d'oeuvre féminine ,Sustainable agriculture ,tillage systems ,F07 - Façons culturales ,Agroforestry ,No-till ,water conservation ,PE&RC ,Soil carbon ,Plant Production Systems ,Soil conservation ,E16 - Économie de la production ,Conservation agriculture ,Soil Science ,Soil quality ,Petite exploitation agricole ,Matière organique du sol ,soil carbon sequestration ,Fertilité du sol ,Soil retrogression and degradation ,Agricultural productivity ,organic-matter ,Productivity ,business.industry ,L01 - Élevage - Considérations générales ,P35 - Fertilité du sol ,Rôle des femmes ,biological nitrogen-fixation ,cropping systems ,Zero tillage ,sustainable agriculture ,Farm/Enterprise Scale ,sub-saharan africa ,Agriculture ,Plantaardige Productiesystemen ,Business ,Plante de culture ,Adoption of innovations ,semiarid west-africa ,southwestern nigeria ,Agronomy and Crop Science - Abstract
Conservation agriculture is claimed to be a panacea for the problems of poor agricultural productivity and soil degradation in sub-Saharan Africa (SSA). It is actively promoted by international research and development organisations, with such strong advocacy that critical debate is stifled. Claims for the potential of CA in Africa are based on widespread adoption in the Americas, where the effects of tillage were replaced by heavy dependence on herbicides and fertilizers. CA is said to increase yields, to reduce labour requirements, improve soil fertility and reduce erosion. Yet empirical evidence is not clear and consistent on many of these points nor is it always clear which of the principles of CA contribute to the desired effects. Although cases can be found where such claims are supported there are equally convincing scientific reports that contradict these claims. Concerns include decreased yields often observed with CA, increased labour requirements when herbicides are not used, an important gender shift of the labour burden to women and a lack of mulch due to poor productivity and due to the priority given to feeding of livestock with crop residues. Despite the publicity claiming widespread adoption of CA, the available evidence suggests virtually no uptake of CA in most SSA countries, with only small groups of adopters in South Africa, Ghana and Zambia. We conclude that there is an urgent need for critical assessment under which ecological and socio-economic conditions CA is best suited for smallholder farming in SSA. Critical constraints to adoption appear to be competing uses for crop residues, increased labour demand for weeding, and lack of access to, and use of external inputs.
- Published
- 2009
263. Soil construction: A step for ecological reclamation of derelict lands
- Author
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Stéphanie Ouvrard, Claire Sauvage, Geoffroy Séré, Christophe Schwartz, Jean-Christophe Renat, Jean-Louis Morel, Laboratoire Sols et Environnement (LSE), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), and Groupe TVD
- Subjects
compost ,sol ,technogenic material ,Stratigraphy ,trace elements ,Technosol ,010501 environmental sciences ,récupération du sol ,01 natural sciences ,boue résiduaire ,Water balance ,pedo-engineering ,industrial wastewater ,Land reclamation ,Soil functions ,soil construction ,2. Zero hunger ,déchet industriel ,sewage sludge ,Ecology ,soil fertility ,04 agricultural and veterinary sciences ,6. Clean water ,fertilité du sol ,Soil horizon ,traitement thermique ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,lysimétrie ,soil ,12. Responsible consumption ,Technosols ,biomasse végétale ,0105 earth and related environmental sciences ,Earth-Surface Processes ,bilan hydrique du sol ,derelict land reclamation ,soil functions ,15. Life on land ,13. Climate action ,restauration du sol ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,soil water balance ,Soil fertility ,Mulch ,lysimetry ,mass balance ,technosol - Abstract
Goal, Scope and Background. Efficient and environmentally friendly technologies for soil reclamation require efforts to develop innovative processes. Alternative technologies to drastic techniques (containment, total removal of soil) are receiving increasing interest. They are based either on the use of ameliorants (e.g. lime, fertilizer, organic mulch) and more recently on the spreading of organic wastes (e.g. compost, sewage sludge). This paper presents a new process of soil construction using wastes and industrial by-products which are formulated and stacked in layers to build a new soil profile over in situ degraded substrates. Work was conducted to assess the feasibility of the ecological reclamation, focusing on the major functions of constructed Technosols. Materials and Methods. Two large lysimetric plots (10 x 10 in) were built on a former coking plant, and two strategies of constructed soil profiles were compared: i) a control soil using thermally treated industrial soil available in situ, and ii) a constructed soil with a combination of thermally treated industrial soil mixed with exogenous materials such as green waste compost and paper mill sludge. Rainfall was measured periodically, drainage effluent was collected, and aliquots were sampled per plot. Plants were collected in 8 replicates for each plot. Results. Water balance data showed that about 10% of the rain water percolated through the constructed soil profiles. Drainage effluent contained a low concentration of contaminants, below the French water drinking standards. Plants grew without any deficiency symptoms on both plots. Apart from the sowed plants, indigenous species developed on the constructed Technosols. Discussion. The experimental set-up was representative of the real conditions for the implementation of such reclamation technologies. In spite of the significant concentrations of trace elements in the parent materials, the fluxes in the drainage effluent were very low because of the high pH. Significantly higher biomass values were recorded on the constructed soil than on the control, as well as a better development of indigenous plants. Conclusions. The constructed soils are examples of Technosols as they are made exclusively of technogenic parent materials. Our results showed that they can behave like natural soils (water cycle, trace elements filtration, biomass production). The process of soil construction is not only an efficient way to reclaim derelict lands, but also a safe alternative for the recycling of wastes and by-products with a minimum use of unpolluted and fertile agricultural soil. Recommendations. The restoration of soil functions, thanks to the soil construction process, must be considered as a primary step for the ecological reclamation of derelict lands. In this way, the pedo-engineering approach should be considered as an essential part of the global ecological engineering for the reclamation of derelict lands. Perspectives. Two major outlooks appear: i) testing a larger variety of wastes and by-products as parent materials for different constructed soils, ii) generalize the results on constructed soils to the characterization of Technosols.
- Published
- 2008
264. Integrating new soyabean varietes for soil fertility management in smallholder systems through participatory research: Lessons from western Kenya
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Paul Richards, Joshua J. Ramisch, Pablo Tittonell, Ken E. Giller, and Michael Misiko
- Subjects
Glycine max ,Agriculteur ,F08 - Systèmes et modes de culture ,Participatory monitoring ,Participatory action research ,farmers ,CERES ,F30 - Génétique et amélioration des plantes ,Petite exploitation agricole ,Soil management ,Fertilité du sol ,acceptability ,Légumineuse à grains ,crop ,Critère de sélection ,improvement ,technologies ,criteria ,Expérimentation au champ ,business.industry ,Agroforestry ,Participation ,food and beverages ,methodology ,PE&RC ,Leerstoelgroep Technologie en agrarische ontwikkeling ,Geography ,Plant Production Systems ,africa ,Agriculture ,Plantaardige Productiesystemen ,Technology and Agrarian Development ,Animal Science and Zoology ,Soil fertility ,business ,Agronomy and Crop Science - Abstract
The aim of this paper was to understand the process of selecting soybean ( Glycine max [L.] Merr.) promiscuous varieties by smallholders for soil fertility management in western Kenya. Eight varieties were screened on 2.5 m × 3 m plots that were managed according to farmers’ practices and evaluated through participatory monitoring and evaluation approaches. Farmers selected preferred varieties and explained their reasons (criteria) for making the selections. Seven promiscuous varieties had better yields than a local one. Farmers’ selection criteria fell into three broad categories relating to yield, appearance and labour. Selection criteria were not primarily aimed to improve soil fertility. This created a challenge to embed the new varieties within the local farming systems for soil fertility improvement. This study shows that farmer criteria for selecting varieties overlapped with scientific procedures. We propose co-research activities targeted to strengthen farmer experimentation skills, their understanding on N addition, and the role of P.
- Published
- 2008
265. Nutrient sufficiency levels for haskap (Lonicera caerulea L.) using the boundary-line approach.
- Author
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Iheshiulo, Ekene Mark-Anthony, Abbey, Lord, and Hammermeister, Andrew M.
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HONEYSUCKLES ,PLANT nutrients ,PLANT productivity ,PLANT growth ,SOIL fertility - Abstract
Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2019
- Full Text
- View/download PDF
266. Remediation of Heavy Metal-Contaminated Soils and Enhancement of Their Fertility with Actinorhizal Plants
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Mame Ourèye Sy, Laurent Laplaze, Antony Champion, Alioune Sarr, Mariama Ngom, Nathalie Diagne, Maimouna Cissokho, Mathieu Ndigue Faye, Daouda Ngom, Babou Ndour, Pape Ibrahima Djighaly, Sherametti, A. (ed.), and Varma, A. (ed.)
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Pollution ,Pollutant ,FERTILITE DU SOL ,Environmental remediation ,media_common.quotation_subject ,FIXATION BIOLOGIQUE DE L'AZOTE ,PHYTOREMEDIATION ,Phytoremediation ,POLLUTION ,Microbial population biology ,Environmental protection ,Soil water ,METAL LOURD ,Environmental science ,DEGRADATION DU SOL ,RELATION SOL PLANTE ,MYCORHIZE ,Soil fertility ,Actinorhizal plant ,media_common - Abstract
Heavy metal-contaminated soils are a major concern for worldwide agricultural production. The main sources of environment pollution by heavy metal are the rapid urbanization and/or industrial growth. These pollutants induce the loss of the structure and the function of soil and microbial community. They affect human health through food chain and water contamination. To rehabilitate lands degraded by heavy metal, some efficiency and low-cost approaches have to be promoted widely. Phytoremediation is a potential tool to clean up pollutants from the contaminated site, implement a ground cover, and improve soil fertility. It is well known that symbiotic microorganisms tolerant to heavy metal increase plant resistance and toxic metal alleviation. So, management of the relationship between hyper-accumulator plants and these microorganisms increases the potential of this biological tool. In this chapter, we discuss (1) the use of actinorhizal plants for remediation of heavy metal-contaminated soils, (2) the impact of mycorrhizal fungi and/or nitrogen-fixing bacteria on plant adaptation and performance in heavy metal-contaminated sites, and (3) the positive effect of actinorhizal plants on soil fertility of heavy metal-contaminated soil.
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- 2015
267. Tierras llaneras de Venezuela : tierras de buena esperanza
- Author
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Brossard, Michel, Hien, E., Ndour, N.Y.B., Leprun, Jean-Claude, Lopez Hernandez, D., Lopez Falcon, R. (ed.), Hétier, Jean-Marie (ed.), Lopez Hernandez, D. (ed.), Schargel, R. (ed.), and Zinck, A. (ed.)
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FERTILITE DU SOL ,AGRICULTURE ,SOL CULTIVE ,ETUDE COMPARATIVE ,SYSTEME DE PRODUCTION ,SAVANE ,UTILISATION DU SOL ,JACHERE - Published
- 2015
268. Conservation agriculture in Southeast Asia
- Author
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Anonth Khamhoung, Pascal Lienhard, and Jean-Claude Legoupil
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F08 - Systèmes et modes de culture ,Pauvreté ,agroécologie ,agriculture alternative ,Agricultural land ,Agroforestry ,Tillage ,séquestration du carbone ,Geography ,P01 - Conservation de la nature et ressources foncières ,Biodiversité ,Conservation agriculture ,Oryza sativa ,Petite exploitation agricole ,Conservation des ressources ,Soil retrogression and degradation ,Fertilité du sol ,Soil governance ,Riz pluvial ,K70 - Dégâts causés aux forêts et leur protection ,Intensification ,Changement climatique ,Niveau de vie ,Érosion ,business.industry ,P35 - Fertilité du sol ,A01 - Agriculture - Considérations générales ,Forestry ,Crop rotation ,Déboisement ,Agriculture ,Développement durable ,Système de culture ,Soil fertility ,business - Abstract
In Southeast Asia (SEA), the joint process of deforestation, agricultural land expansion, and intensification has led to vast soil erosion and a general decrease in soil and water quality. In addition, current agricultural practices such as deep plowing of soil or burning of forest and crop residues favor CO2 emissions and contribute to global warming. The deforestation rate in SEA is important (0.91 % per year of the forest area) and soil degradation is important either by erosion or acidity (63 % of the total land area). Conservation agriculture (CA) is an alternative land-use system reconciling economic viability, social balance, soil fertility restoration, and environmental conservation as well as climate change adaptation, which are crucial elements for the long-term improvement of smallholders’ living conditions and poverty alleviation. A basket of CA technologies, including zero or reduced tillage, direct seeding, crop rotations, soil cover, and residue management has been developed in different countries. Adoption of CA technologies has regenerated fertility of degraded soils, provided livestock with high-quality forage, and increased soil carbon sequestration. New innovative farming systems need to be developed to successfully integrate crops and livestock by offering numerous advantages such as diversification of income through animal products such as milk, meat, fiber and manure, weed control, soil erosion control, increased yield of main crops, and income during the “start-up” period for tree crops. The development of farming systems, which are more intensive and respectful of natural resources and the environment, requires acquisition of new stakeholder knowledge and skills. This is a priority since these stakeholders will initiate the required changes. The Conservation Agriculture Network for Southeast Asia (CANSEA) was created in 2009 to optimize similarities and complementarities among countries and institutions in SEA to improve the efficiency of research carried out by the various programs, and to optimize resources and means.
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- 2015
269. Legacy of logging roads in the Congo Basin: How persistent are the scars in forest cover?
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John R. Healey, Fritz Kleinschroth, Sylvie Gourlet-Fleury, Frédéric Mortier, and Plinio Sist
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Forêt tropicale humide ,geological substrate ,Central Africa ,Ecology ,Logging ,Exploitation forestière ,Vegetation ,GIS ,Geography ,Route forestière ,Reconstitution forestière ,Télédétection ,Forest management ,Restauration couverture végétale ,Abattage d'arbres ,LANDSAT ,Deforestation ,lcsh:QH540-549.5 ,Fertilité du sol ,deforestation ,J12 - Manutention, transport, stockage et conservation des produits forestiers ,Couverture végétale ,Revegetation ,K70 - Dégâts causés aux forêts et leur protection ,Ecology, Evolution, Behavior and Systematics ,land cover change ,Land use ,Road ecology ,Impact sur l'environnement ,Forestry ,Régénération naturelle ,Déboisement ,K10 - Production forestière ,dégradation des forêts ,Species richness ,lcsh:Ecology ,U30 - Méthodes de recherche - Abstract
Logging roads in the Congo Basin are often associated with forest degradation through fragmentation and access for other land uses. However, in concessions managed for timber production, secondary roads are usually closed after exploitation and are expected to disappear subsequently. Little is known about the effectiveness of this prescription and the factors affecting vegetation recovery rate on abandoned logging roads. In a novel approach we assessed logging roads as temporary elements in the forest landscape that vary in persistence depending on environmental conditions. We analyzed road persistence during the period 1986–2013 in adjacent parts of Cameroon, Central African Republic and Republic of Congo. Three successive phases of road recovery were identified on LANDSAT images: open roads with bare soil, roads in the process of revegetation after abandonment and disappeared roads no longer distinguishable from the surrounding forest. Field based inventories confirmed significant differences between all three categories in density and richness of woody species and cover of dominant herbs. We used dead-end road segments, built for timber exploitation, as sampling units. Only 6% of them were identified as being re-opened. Survival analyses showed median persistence of four years for open roads before changing to the revegetating state and 20 years for revegetating roads before disappearance. Persistence of revegetating roads was 25% longer on geologically poor substrates which might result from slower forest recovery in areas with lower levels of soil nutrient content. We highlight the contrast amongst forests growing on different types of substrate in their potential for ecosystem recovery over time after roads have been abandoned. Forest management plans need to take these constraints into account. Logging activities should be concentrated on the existing road network and sites of low soil resource levels should be spared from business-as-usual exploitation. (Resume d'auteur)
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- 2015
270. Short-term effects of conversion from reduced tillage to direct-seeding mulch-based cropping systems
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Rémy Kulagowski and Anaïs Chailleux
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P33 - Chimie et physique du sol ,Semis direct ,F08 - Systèmes et modes de culture ,Soil Science ,Plant Science ,Teneur en azote ,Zea mays ,Culture sous couvert végétal ,agriculture alternative ,Fertilité du sol ,Genetics ,Cover crop ,F07 - Façons culturales ,biology ,Crop yield ,P35 - Fertilité du sol ,Sorghum bicolor ,Sorghum ,biology.organism_classification ,Soil quality ,Tillage ,Potentiel hydrique du sol ,Climat méditerranéen ,Rendement des cultures ,Agronomy ,Soil water ,Environmental science ,Travail du sol de conservation ,Agronomy and Crop Science ,Mulch ,Sweet sorghum - Abstract
Conservation tillage is one strategy whereby both sustainability and productivity can be achieved by improving the soil quality. Although reduced tillage (RT) is widely practiced, more conservative strategies, such as direct-seeding mulch-based cropping systems (DMC), are less frequent. Here we assessed the effect of conversion from RT to DMC in three commercial fields in southern France (inland Mediterranean climate). Two fields were cropped with maize (Zea mays L.) and one with sorghum (Sorghum bicolor L.), and monitored during 15 months. We found higher soil water potential retention in DMC than in RT at 10, 30, and 60 cm soil depth. Conversely, nitrogen availability was slightly higher in the RT treatment. Crop development was not affected by the soil practices, but crop yields were higher in the DMC treatment for one maize field and the sorghum field (plus 3.04 t/ha harvested in the DMC treatment when compared to the RT treatment in the maize field and plus 2.105 t/ha in the sorghum one). This study demonstrates that DMC can provide short-term benefits in farm fields in southern France, but these benefits are not automatic and the conditions under which they are obtained remain to be clarified.
- Published
- 2015
271. Analyse des flux de biomasse et des transferts de la fertilité à l'échelle du territoire villageois en Afrique sub-sahélienne : opportunités d'intégration fonctionnelle agriculture - élevage
- Author
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Diarisso, Tidiane
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F08 - Systèmes et modes de culture ,gestion des ressources naturelles ,Déchet agricole ,Fertilisation ,Fertilité du sol ,Biomasse ,L01 - Élevage - Considérations générales ,P35 - Fertilité du sol ,Pâturages ,Q70 - Traitement des déchets agricoles ,Utilisation des déchets ,Rendement des cultures ,Cycle de l'azote ,Système agropastoral ,Fumure d'entretien - Abstract
Dans les systèmes agropastoraux d'Afrique de l'ouest les résidus de récolte disponibles sur les parcelles récoltées au sein des territoires villageois constituent une source capitale de fertilisants organiques pour l'entretien de la productivité des sols des exploitations agricoles. Leur accès est régi par les règles de vaines pâtures instaurées par les autorités traditionnelles qui autorisent la consommation des résidus de récolte par les troupeaux du village et ceux des troupeaux transhumants. Des contrats de fumure entre producteurs sans troupeaux et producteurs détenteurs de troupeaux permettent ainsi des restitutions de fumure sur les parcelles des premiers en échange de résidus. Ces règles et contrats se traduisent par des flux de biomasses (résidus de récolte et fumure organique) et des transferts de fertilité des sols entre exploitations agricoles au sein du territoire villageois. La croissance démographique rapide observée en Afrique de l'Ouest accompagnée du développement de la traction animale a conduit à une augmentation des surfaces cultivées, des effectifs animaux et à une saturation de l'espace agricole. La disparition associée des contrats de fumure entre les exploitations s'est traduite par une accumulation de fertilité sur les parcelles des producteurs détenteurs de troupeaux au détriment de ceux sans troupeaux. L'objectif de cette thèse est d'explorer différents scénarios de changements de flux de nutriments à l'échelle du territoire villageois sur le fonctionnement des systèmes agropastoraux et la productivité du sol afin de contribuer à l'élaboration de cadres de gestion des ressources agropastorales (résidus de récolte et herbes de pâturage). On a construit quatre types d'exploitation sur la base de leurs capacités de production (nombre d'animaux, main d'oeuvre, équipement, etc.) et des objectifs de production. On a choisi trois exploitations par type (12 exploitations au total par village) pour lesquelles on : i) a quantifié tous les flux de ressources organiques et inorganiques à trois niveaux : l'exploitation, les sous-systèmes de l'exploitation, et les parcelles de l'exploitation ; et ii) évalué l'efficacité de l'utilisation des nutriments et réaliser les bilans en nutriments. Un modèle multi-agents a été développé prenant en compte les transferts de biomasses et des nutriments entre les différentes exploitations agricoles. Les effets de changements climatiques (baisse de 25 % de la pluviométrie par rapport à celle observée dans la zone d'étude) et de l'introduction de 10 % ou 30 % de l'agriculture de conservation sur la production de grain de maïs et la fumure organique chez les exploitations agricoles ont été explorés. Quatre types d'exploitation ont été identifies : producteur d'agriculture de subsistance (SO), producteur intégré au marché (MO), l'agriculteur –éleveur (AE) et l'éleveur – agriculteur (EA). Les deux derniers types d'exploitation collectent au moins 50 % de leurs résidus de récolte qu'ils conservent comme stock fourrager, contre 30 % pour les autres types. Les animaux des types, AE et EA consomment aussi 90 % des résidus restant sur leurs parcelles avant de consommer ceux sur les parcelles des autres types d'exploitation. Le fumier de bovins disponibles dans le village est principalement utilisé pour fertiliser les champs des types d'exploitation, AE et EA. Ces dernières présentent souvent des bilans en nutriments positifs. Les rendements moyens de cultures principales et l'efficience agronomique de l'azote moyen observé étaient beaucoup plus faibles, et de larges écarts ont été révélés entre les types d'exploitations. La conversion de 30 % de superficie cultivable en agriculture de conservation a un résultat négatif sur la production en grain de maïs à l'échelle du territoire villageois mais positif à l'échelle de l'exploitation pour les types SO et MO. Dans le scénario climatique, les types éleveur – agriculteur et agriculteur -éleveur subissent de manière générale les plus grandes baisses de productions en grain et en fumure organique que les autres types. L'amélioration de la gestion interne de nutriments grâce à un meilleur recyclage des biomasses, et l'utilisation plus efficace des engrais disponible est la première option pour les exploitations à faible facultés en ressources de production.
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- 2015
272. Biomass transfers and nutrient budgets of the agro-pastoral systems in a village territory in south-western Burkina Faso
- Author
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Pablo Tittonell, Nadine Andrieu, Marc Corbeels, Tidiane Diarisso, and Patrice Djamen
- Subjects
Résidu de récolte ,Crop residue ,F08 - Systèmes et modes de culture ,Biomasse ,Grazing ,Enquête ,Agroforestry ,Pâturages ,PE&RC ,cover change ,Geography ,Agroécosystème ,crop-livestock system ,Livestock ,Rangeland ,Azote ,Pastoralism ,Soil Science ,Forage ,farmers ,Crop ,northern nigeria ,Terre communale ,vegetation ,Fertilité du sol ,management strategies ,Propriété physicochimique du sol ,business.industry ,L01 - Élevage - Considérations générales ,P35 - Fertilité du sol ,Étude de cas ,forage ,sahel ,Farm Systems Ecology Group ,Méthode d'élevage ,africa ,Agriculture ,Système agropastoral ,Potassium ,farming system ,Terre de pâturage ,business ,Agronomy and Crop Science - Abstract
Privatisation of grazing resources is emerging in the agro-pastoral systems of West Africa, resulting in increased pressure on the remaining communal rangelands and greater competition between farmers for access to crop residues. Differential management strategies arise as determined by household diversity. This study quantified the flows of biomass and related nutrient budgets in relation to farm diversity in Koumbia, a representative village of south-western Burkina Faso. Four farm types were identified: subsistence-oriented and market oriented crop farmers, agro-pastoralists and pastoralists. Crop farmers collected about 30 % of their maize harvest residues for feeding during the dry hot season, while agro-pastoralists and pastoralists stocked about 50 % of their maize residues. Whilst the remaining crop residues on (agro)pastoralist farms were almost entirely grazed by their own cattle, about 90 % of the crop residues of crop farmers were consumed by cattle of (agro)pastoralists. On the other hand, available manure from cattle in the village was mainly used to fertilize the fields of the livestock owners. As a result, the cropped land of farmers with few livestock is continuously mined for nutrients. Calculated partial balances of N and K at farm level were negative for all farm types, except for N in the case of pastoralist farms. N and K balances of cropped fields were generally negative on all farm types. Partial balances of P were generally positive, which was to a large extent due to P fertilizer use. Better integration of crop and livestock production activities on farms and between farms offers a pathway to more efficient nutrient cycling with reduced nutrients losses.
- Published
- 2015
273. Multi-scale trade-off analysis of cereal residue use for livestock feeding vs. soil mulching in the Mid-Zambezi Valley, Zimbabwe
- Author
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Pablo Tittonell, Frédéric Baudron, Sylvestre Delmotte, Juan Manuel Herrera, Marc Corbeels, International Maize and Wheat Improvement Center (CIMMYT), Consultative Group on International Agricultural Research [CGIAR] (CGIAR), Innovation et Développement dans l'Agriculture et l'Alimentation (UMR Innovation), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Farming Systems Ecology, Wageningen University and Research [Wageningen] (WUR), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Empresa Brasileira de Pesquisa Agropecuária (Embrapa), Ministério da Agricultura, Pecuária e Abastecimento [Brasil] (MAPA), Governo do Brasil-Governo do Brasil, and Consejo Nacional de Investigaciones Científicas y Técnicas
- Subjects
knowledge ,Crop residue ,010504 meteorology & atmospheric sciences ,[SDV]Life Sciences [q-bio] ,F08 - Systèmes et modes de culture ,01 natural sciences ,nitrogen ,[SHS]Humanities and Social Sciences ,2. Zero hunger ,biology ,U10 - Informatique, mathématiques et statistiques ,apsim ,food and beverages ,04 agricultural and veterinary sciences ,Sorghum bicolor ,PE&RC ,Aliment pour animaux ,conservation agriculture ,Rendement des cultures ,quality ,agricultural production systems simulator ,Livestock ,Fertilizer ,village ,Conservation agriculture ,engineering.material ,Paillage ,Fertilisation ,Petite exploitation agricole ,Culture sous couvert végétal ,equity ,Fertilité du sol ,0105 earth and related environmental sciences ,L02 - Alimentation animale ,Gossypium ,Plante céréalière ,model ,business.industry ,simulation model ,carbon ,P35 - Fertilité du sol ,Farm Systems Ecology Group ,Modèle de simulation ,15. Life on land ,Sorghum ,biology.organism_classification ,Manure ,africa ,Agronomy ,040103 agronomy & agriculture ,engineering ,systems ,0401 agriculture, forestry, and fisheries ,Environmental science ,Animal Science and Zoology ,Soil fertility ,business ,Agronomy and Crop Science ,Mulch - Abstract
International audience; Cereal residues represent a major resource for livestock feeding during the dry season in southern Africa. When kept on the soil surface instead of feeding them to livestock, crop residues can contribute to increasing soil fertility and maintaining crop productivity in the short- and the long-term. We explored these trade-offs for smallholder cotton–sorghum farming systems in the semi-arid Zambezi Valley, northern Zimbabwe. The analysis was done using simulation models at three scales, the plot, the farm and the territory, to simulate the effects of different sorghum residue allocations to livestock feeding vs. soil mulching, in combination with different application rates of mineral nitrogen fertilizer on crop productivity. The plot-scale simulations suggest that without N fertilization soil mulching has a positive effect on cotton yields only if small quantities of sorghum residues are used as mulch (average cotton yields of 2.24 ± 0.41 kg ha−1 with a mulch of 100 kg ha−1 vs. 1.91 ± 0.29 kg ha−1 without mulch). Greater quantities of mulch have a negative effect on cotton yield without N fertilization due to N immobilization in the soil microbial biomass. With applications of 100 kg N ha−1, quantities of mulch up to 3 t ha−1 have no negative effect on cotton yield. Results at farm-scale highlight the fundamental role of livestock as a source of traction, and the need to feed a greater proportion of sorghum residues to livestock as herd and farm sizes increase. Farmers with no livestock attained maximum crop production when 100% of their sorghum residue remained in the field, as they do not have access to cattle manure. The optimum fraction of crop residue to be retained in the fields for maximum farm crop production varied for farmers with 2 or less heads of cattle (80% retention), with 2–3 heads (60–80%), with 4 or more heads (40–60%). At the scale of the entire territory, total cotton and sorghum production increased with the density of cattle, at the expense of soil mulching with crop residues. The results of our simulations suggest that (i) the optimum level of residue retention depends on the scale at which trade-offs are analyzed; (ii) the retention of all of the crop residue as mulch appears unrealistic and undesirable in farming systems that rely on livestock for traction; and (iii) crop residue mulching could be made more attractive to farmers by paying due attention to balancing C to N ratios in the soil and by promoting small-scale mechanization to replace animal traction.
- Published
- 2015
274. Promoting soil health and productivity in Eastern Arc mountain ecosystems through collaboration and networks
- Author
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Njeru, C., Calatayud, Paul-André, Le Rü, Bruno, Mohamed, S., Ndonye, S., Johansson, T., Romeo, R. (ed.), Vita, A. (ed.), Manuelli, S. (ed.), Zanini, E. (ed.), Freppaz, M. (ed.), and Stanchi, S. (ed.)
- Subjects
PROJET DE DEVELOPPEMENT ,CONSERVATION DU SOL ,FERTILITE DU SOL ,SOL CULTIVE ,AGROFORESTERIE ,MISE EN VALEUR DU SOL ,food and beverages ,PRODUCTION AGRICOLE ,SOL DEGRADE ,PAUVRETE ,PRATIQUE CULTURALE ,VULGARISATION AGRICOLE ,DEVELOPPEMENT RURAL ,ZONE DE MONTAGNE ,HAUTE ALTITUDE - Abstract
Smallholder farmers in the Taita hills and Mount Kilimanjaro recognize the need to conserve soil nutrients of fields and farms located in the upper, middle and lower zones of mountainous areas. These mountain communities depend on rain-fed subsistence agriculture which means that for sustainable subsistence crop production, they also depend on nutrient availability and use efficiency in farming households. A study under way in the area has looked at loss of land cover and infestations of plant pests and diseases and is using this information to raise farmers’ awareness of soil fertility and to introduce best cropping practices.
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- 2015
275. Effect of ramial wood amendment on sorghum production and topsoil quality in a Sudano-Sahelian ecosystem (central Burkina Faso)
- Author
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Aurélien Penche, Cathy Clermont-Dauphin, Bernard Barthès, Philippe Deleporte, Edmond Hien, Laurent Cournac, Raphaël J. Manlay, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), UFR-SVT, Université de Ouagadougou, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), AgroParisTech, Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Université Joseph Ki-Zerbo [Ouagadougou] (UJZK), IRD, UMR Eco&Sols, Montpellier, France, IRD, UMR Eco&Sols, Ouagadougou, Burkina Faso, and CIRAD, UMR Eco&Sols, Montpellier, France
- Subjects
010504 meteorology & atmospheric sciences ,F08 - Systèmes et modes de culture ,termites ,forêt tropicale ,01 natural sciences ,Mineralization (biology) ,tropical dry Africa ,Minéralisation ,soil phosphorus ,soil carbon ,Organic amendments ,Engrais organique ,2. Zero hunger ,Litière végétale ,Forestry ,04 agricultural and veterinary sciences ,Sorghum bicolor ,Straw ,6. Clean water ,Rendement des cultures ,[SDE]Environmental Sciences ,Branche ,P33 - Chimie et physique du sol ,Fixation de l'azote ,Amendment ,chemistry.chemical_element ,Biology ,Fertilisation ,Crop ,Fertilité du sol ,Matière organique ,Arbre forestier ,0105 earth and related environmental sciences ,Topsoil ,Phosphorus ,Impact sur l'environnement ,Soil carbon ,15. Life on land ,Sorghum ,biology.organism_classification ,K10 - Production forestière ,chemistry ,Agronomy ,branches ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Agronomy and Crop Science - Abstract
Erratum paru dans Agroforestry Systems = ISSN 0167-4366. - (2015)vol.89:n°1 p. 95-96. In Sudano-Sahelian agriculture, organic amendments are often limited by resource availability. Small branches (ramial wood, RW) represent an organic resource found in many landscapes but little is known about their effects. This field trial (2007-2009) studied the effects of RW or straw at low application rate (0.69 Mg C ha?1 year?1) on topsoil carbon (C), nitrogen (N) and available phosphorus (P, Pav), termite cast abundance, and sorghum yield. Straw and RW were chopped and either buried (StBu, WoBu) or mulched (StMu, WoMu). Mineral fertilizers were added to straw so that RW- and straw-amended plots received similar applications of C, N, P, and potassium. Another treatment had RW buried with additional N (WoBuN), and there was a control (Ctrl). Branches came from Piliostigma reticulatum, very common in the area. The treatments had little significant effect on topsoil and crop, owing to the low application rate and spatial variability. However, Pav was significantly lower with buried than mulched amendments in 2009, and decreased significantly over time in Ctrl and with buried amendments. Topsoil C also decreased significantly with time in WoMu. Significantly more termite casts were observed with RW. The sorghum yield averaged 0.87 Mg DM ha?1 in 2007 and then decreased. The treatments affected yield significantly in 2008 only: it was higher in WoBuN and StBu than in Ctrl. In 2009, the yield was mainly affected by initial topsoil Pav. These results suggest that RW stimulated biological activity, leading to P immobilization and C mineralization, but had little effect on yields.
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- 2015
276. Les sociétés rurales face aux changements climatiques et environnementaux en Afrique de l'Ouest
- Author
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Sultan, Benjamin, Lalou, Richard, Amadou Sanni, M., Oumarou, A., Soumaré, M.A., Processus de la variabilité climatique tropicale et impacts (PARVATI), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Population-Environnement-Développement (LPED), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636))
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INNOVATION ,CONSEQUENCE ECOLOGIQUE ,PRODUCTION AGRICOLE ,[SHS.DEMO]Humanities and Social Sciences/Demography ,RESSOURCES EN EAU ,FONCIER RURAL ,RISQUE CLIMATIQUE ,ADAPTATION SOCIALE ,RECHERCHE PLURIDISCIPLINAIRE ,IMPACT SOCIOECONOMIQUE ,ELEVAGE ,MIGRATION TEMPORAIRE ,ComputingMilieux_MISCELLANEOUS ,FERTILITE DU SOL ,[SHS.GEO]Humanities and Social Sciences/Geography ,[SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology ,1950 2010 ,EVOLUTION ,PRATIQUE CULTURALE ,CHANGEMENT TECHNIQUE ,SYSTEME AGRAIRE ,CLIMAT ,LIV ,PRECIPITATION ,CHANGEMENT CLIMATIQUE ,CHANGEMENT SOCIAL ,SOCIETE RURALE ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,IMPACT SUR L'ENVIRONNEMENT - Abstract
L'avenir de l'Afrique de l'Ouest dépend de la capacité de son agriculture à assurer la sécurité alimentaire de sa population, qui devrait doubler en vingt ans, tout en faisant face aux risques nouveaux engendrés par le réchauffement climatique. En effet, les modifications de température et de précipitations déjà à l'oeuvre, et qui devraient s'amplifier, auront dans un futur proche des répercussions importantes sur la production agricole et sur les ressources en eau de cette partie du continent africain. L'adaptation des sociétés rurales aux risques climatiques est une des clés pour relever ce nouveau défi. Pour mieux en connaître le potentiel, les processus et les barrières, cet ouvrage analyse les évolutions récentes et en cours du climat et de l'environnement, et étudie comment les sociétés rurales les perçoivent et les intègrent : quels sont les impacts de ces changements, quelles vulnérabilités mais aussi quelles nouvelles opportunités entraînent-ils ? Comment les populations s'y adaptent-elles, et quelles innovations mettent-elles en oeuvre, alors que les effets induits par le climat interagissent avec les changements sociaux, politiques, économiques et techniques en cours sur le continent ? En associant des chercheurs français et africains (climatologues, agronomes, hydrologues, écologues, démographes, géographes, anthropologues, sociologues...) dans une approche interdisciplinaire, cet ouvrage apporte une contribution précieuse pour mieux anticiper les risques climatiques et évaluer les capacités des sociétés africaines à y faire face.
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- 2015
277. Fertilité des sols et minéralisation de l'azote : sous l'influence des pratiques culturales, quels processus et interactions sont impliqués ?
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Recous, Sylvie, Chabbi, Abad, Vertes, Francoise, Thiebeau, Pascal, Chenu, C., Fractionnement des AgroRessources et Environnement (FARE), Université de Reims Champagne-Ardenne (URCA)-Institut National de la Recherche Agronomique (INRA), Unité de Recherche Pluridisciplinaire Prairies et Plantes Fourragères (P3F), Institut National de la Recherche Agronomique (INRA), Sol Agro et hydrosystème Spatialisation (SAS), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Fractionnement des AgroRessources et Environnement - UMR-A 614 (FARE), Université de Reims Champagne-Ardenne (URCA)-Institut National de la Recherche Agronomique (INRA)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS), and AGROCAMPUS OUEST-Institut National de la Recherche Agronomique (INRA)
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microorganism ,cycle du carbone ,[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,sol ,fertilité des sols ,dynamique des matières organiques ,retournement du couvert végétal ,nitrogen ,soil ,cycle de l'azote ,carbon cycle ,nitrogen cycle ,système de culture ,pratique culturale ,organic matter ,azote ,carbone ,fertilité du sol ,matière organique ,micro-organisme ,prairie ,rotation culturale ,semis direct ,travail du sol ,carbon ,crop succession ,crop system ,direct seeding ,grassland ,ploughing-up of vegetal cover ,soil fertility ,soil tillering ,temporary pastures ,Agricultural sciences ,prairie temporaire ,Sciences agricoles - Abstract
La fertilité des sols, notion centrale pour accroître la production des écosystèmes cultivés, est une réalité complexe : elle résulte de l'expression des composantes biologiques, physiques et chimiques des sols et de leurs interactions. Comprendre les mécanismes impliqués permet d'envisager les effets de modifications de pratiques ou de système de culture sur la fertilité. La fertilité est ici décrite comme la capacité des sols à fournir les éléments nutritifs nécessaires à l'alimentation des plantes. Le cycle de l'azote et ses relations avec la dynamique des matières organiques y joue un rôle central ; il est couplé au cycle du carbone par l'activité microbienne hétérotrophe qui minéralise (parfois très rapidement) les résidus de récolte. Les interactions entre processus chimiques, physiques et biologiques du sol sont décrites. Il est ainsi possible d'analyser l'influence de pratiques culturales comme la simplification ou la suppression du labour, l'insertion ou la destruction de prairies temporaires dans les rotations et d'envisager une agriculture reposant davantage sur le recyclage des matières organiques et le fonctionnement biologique du sol., In this study, soil fertility is defined as the ability of soils to furnish necessary nutrients to plants. It is a consequence of the biological, chemical, and physical properties of soils and their interactions. The nitrogen cycle and its relationship with soil organic matter dynamics play a key role; the nitrogen cycle is linked to the carbon cycle by the activity of soil bacteria. Here, we describe the interactions between various biological, chemical, and physical processes that take place in the soil. It is thus possible to examine the effects of cultivation practices, such as limiting or eliminating ploughing, including temporary pastures in rotations, and destroying temporary pastures as part of the rotation cycle. One can also envision an agricultural approach that promotes the recycling of organic matter and the soil's biological functions.
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- 2015
278. Aspectos biogeoquimicos de los ciclos de nutritientes en agro-ecosistemas
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Hétier, Jean-Marie, Lopez Hernandez, D., Lopez Falcon, R. (ed.), Hétier, Jean-Marie (ed.), Lopez Hernandez, D. (ed.), Schargel, R. (ed.), and Zinck, A. (ed.)
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METHODE D'ANALYSE ,FERTILITE DU SOL ,CYCLE DE L'AZOTE ,SOL CULTIVE ,MATIERE ORGANIQUE ,SAVANE ,CYCLE BIOGEOCHIMIQUE - Published
- 2015
279. Agroforestry-based diversification for planting cocoa in the savannah of Central Cameroon
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Patrick Jagoret, Eric Malézieux, and Frank Enjalric
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Imperata ,F40 - Écologie végétale ,F08 - Systèmes et modes de culture ,Diversification (marketing strategy) ,Agroforesterie ,Imperata cylindrica ,Matière organique du sol ,Résistance aux facteurs nuisibles ,Fertilité du sol ,K01 - Foresterie - Considérations générales ,Cultivation System ,Clearing ,Theobroma cacao ,Savane ,forêt claire ,biology ,Agroforestry ,business.industry ,Soil organic matter ,P35 - Fertilité du sol ,Sowing ,biology.organism_classification ,Soil quality ,Geography ,Agriculture ,Diversification ,Culture associée ,business - Abstract
Cocoa is a crop often cultivated after clearing forests. This ensures, at least in the initial years, favourable conditions for good agriculture production: a relatively high level of soil organic matter, nutrient availability, limited amount of weeds and reduced pest pressure (Chap. 1). How can we explain the emergence of a new cocoa frontier on degraded soils of the savannah areas in Central Cameroon? Agroforestry-based diversification plays a central ecological and economic role in the establishment of these cocoa farms in the savannah. At the agronomic level, the reconstitution of a multi-species cocoa cultivation system by farmers in the forest-savannah interface area of central Cameroon helps overcome the main constraints presented by such areas for cocoa cultivation (uneven rainfall distribution, poor soil quality and presence of Imperata cylindrica). At the economic level, the benefits of a cocoa agroforestry system in the savannah are also confirmed.
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- 2015
280. Aspectos sobre el manejo y la conservación de Agaves mezcaleros en Michoacan
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Martinez Palacios, A., Chavez Mendoza, S. A., Reyes Gonzalez, R., Aguilar Alberto, A., Lobit, P., Prat, Christian, Martinez Palacios, A. (ed.), Morales Garcia, J. L. (ed.), and Guillén Rodríguez, S. (ed.)
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RECOMMANDATIONS ,AGAVE ,FERTILITE DU SOL ,SYSTEME DE CULTURE ,POLYCULTURE ,PRATIQUE CULTURALE ,STRUCTURE DU SOL ,PLANTATION ,INSECTE NUISIBLE ,CULTURE ASSOCIEE ,PLANTE DE COUVERTURE ,LUMIERE ,PLANTE UTILE ,ZONE DE MONTAGNE ,AGENT PATHOGENE ,HAUTE ALTITUDE ,AGRICULTURE DURABLE - Published
- 2015
281. Accompagner l'innovation en agriculture de conservation : quels apports des agronomes du système de culture ?
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Naudin, Krishna, Le Gal, Pierre-Yves, Ranaivoson, Lalaina, and Scopel, Eric
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F08 - Systèmes et modes de culture ,Travail du sol minimal ,agroécologie ,A01 - Agriculture - Considérations générales ,Q70 - Traitement des déchets agricoles ,Déchet agricole ,Agroécosystème ,Fertilité du sol ,Engrais vert ,Biomasse ,Couverture végétale ,Innovation ,Plante fourragère ,F04 - Fertilisation - Abstract
Dans les pays du sud en général, et en Afrique sub-saharienne en particulier, l'adoption de systèmes de culture innovants en agriculture de conservation (AC) est souvent limitée par la concurrence pour les résidus de culture avec l'élevage. De plus, les bénéfices attendus de l'AC peuvent varier fortement en fonction de la quantité de résidus conservée. Par exemple, la réduction du ruissellement et de l'érosion peut être effective avec moins de 3 t/ha de mulch alors qu'il faudra plus du double pour avoir un effet significatif sur les adventices. D'autre part, la question des usages multiples des résidus doit être traitée à l'échelle de l'exploitation et du territoire. Certaines études à ces échelles font ressortir les contraintes à la pratique des AC, d'autres mettent en avant les complémentarités possibles et notamment les gains mutuels entre agriculture et l'élevage. Pour accompagner la prise de décision des acteurs, paysans ou structures d'appui, nous concluons en proposant un cadre d'analyse commun des fonctions agroécologiques de l'AC.
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- 2015
282. Inheritance and QTL Mapping of Leaf Nutrient Concentration in a Cotton Inter-Specific Derived RIL Population
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Greg A. Constable, Jean-Marc Lacape, Danny J. Llewellyn, and Shiming Liu
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Phénotype ,lcsh:Medicine ,Gossypium ,F30 - Génétique et amélioration des plantes ,Substance nutritive ,Physiologie de la nutrition ,Nutrient ,Metals, Alkaline Earth ,Lignée ,Cultivar ,lcsh:Science ,Absorption de substances nutritives ,education.field_of_study ,Multidisciplinary ,Chromosome Mapping ,Feuille ,food and beverages ,Vertisol ,Cations, Monovalent ,Phenotype ,Agricultural soil science ,Utilisation des nutriments ,Research Article ,Développement biologique ,Locus des caractères quantitatifs ,Cations, Divalent ,Population ,Quantitative Trait Loci ,Gossypium hirsutum ,Biology ,Quantitative trait locus ,Chromosomes, Plant ,Variation génétique ,Metals, Heavy ,Fertilité du sol ,education ,Croissance ,Alleles ,Crosses, Genetic ,lcsh:R ,P35 - Fertilité du sol ,Genetic Variation ,Héritabilité ,Gossypium barbadense ,Heritability ,biology.organism_classification ,Amélioration des plantes ,Plant Leaves ,F61 - Physiologie végétale - Nutrition ,Agronomy ,Carte génétique ,lcsh:Q - Abstract
Developing and deploying cotton cultivars with high nutrient uptake, use efficiency and tolerance to nutrient related soil stresses is desirable to assist sustainable soil management. Genetic variation, heritability, selection response and quantitative trait loci (QTLs) were investigated for five macronutrients (P, K, Ca, Mg, S) and five micronutrients (Fe, Mn, B, Zn, and Cu) in a recombinant inbred line (RIL) population from an inter-specific cross between Gossypium hirsutum cv. Guazuncho 2, and G. barbadense accession VH8-4602. Na and K/Na ratio were also studied as the imbalance between Na and other nutrients is detrimental to cotton growth and development. The concentrations of nutrients were measured for different plant parts of the two parents and for leaf samples of the whole population collected at early to peak flowering in field experiments over two years in a sodic Vertosol soil. Parental contrast was large for most nutrient concentrations in leaves when compared with other plant parts. Segregation for leaf nutrient concentration was observed within the population with transgression for P, K, K/Na ratio and all micronutrients. Genotypic difference was the major factor behind within-population variation for most nutrients, while narrow sense heritability was moderate (0.27 for Mn and Cu, and 0.43 for B). At least one significant QTL was identified for each nutrient except K and more than half of those QTLs were clustered on chromosomes 14, 18 and 22. Selection response was predicted to be low for P and all micronutrients except B, high for K, Na and B, and very high for K/Na ratio. Correlations were more common between macronutrients, Na and K/Na ratio where the nature and strength of the relations varied (r=-0.69 to 0.76). We conclude that there is sufficient genetic diversity between these two tetraploid cotton species that could be exploited to improve cotton nutrient status by introgressing species-unique favourable alleles.
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- 2015
283. Transfert de fertilité et durabilité des systèmes de production : application à la culture du riz
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Fanjaniaina, Marie Lucia, Ramahandry, Fidiniaina, Larvy Delarivière, Jean, Razafimanantsoa, Marie-Paule, Salgado, Paulo, Tillard, Emmanuel, Rabeharisoa, R. Lilia, and Becquer, Thierry
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P33 - Chimie et physique du sol ,Recyclage des déchets ,pH du sol ,Oryza sativa ,Teneur en éléments minéraux ,Substance nutritive ,Acidification ,Fertilité du sol ,Propriété physicochimique du sol ,Durabilité ,Efficacité ,P35 - Fertilité du sol ,Fumier ,Analyse de sol ,cycle nutriments dans écosystèmes ,F04 - Fertilisation - Abstract
La fertilité des sols en zone tropicale diminue due à l'érosion et à l'exportation d'éléments nutritifs dans les récoltes. Le calcul des flux de nutriments transférés à partir des biomasses, soit sortant (grains, pailles). soit entrant (fumiers, etc.). est indispensable pour quantifier les transferts de fertilité à l'échelle des exploitations et évaluer la durabilité des systèmes de production. Les analyses chimiques de la minéralomasse du riz ont montré que les exportations sont, en moyenne, de 13, 7 kg d'azote (N), 1,9 kg de phosphore (Pl. 2,7kg de potassium (K). 1, 1 kg de calcium (Ca) par tonne de grains et 11,5 kg d'N, 0,6 kg de P, 12,0 kg de K, 2,8 kg de Ca de pailles exportées. Ces exportations minérales contribuent à l'acidification des sols. Le recyclage du fumier, qui restitue 40 à 95 % des nutriments, constitue une voie intéressante pour maintenir la fertilité du sol.
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- 2015
284. Légumineuses et prairies temporaires : des fournitures d'azote pour les rotations
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Vertès, Francoise, Jeuffroy, Marie-Helene, Louarn, Gaëtan, Voisin, Anne-Sophie, Justes, Eric, Sol Agro et hydrosystème Spatialisation (SAS), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Agronomie, AgroParisTech-Institut National de la Recherche Agronomique (INRA), Unité de Recherche Pluridisciplinaire Prairies et Plantes Fourragères (P3F), Institut National de la Recherche Agronomique (INRA), Agroécologie [Dijon], Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Agrosystèmes Cultivés et Herbagers (ARCHE), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure Agronomique de Toulouse-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, ProdInra, Archive Ouverte, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Institut National de la Recherche Agronomique (INRA)-École nationale supérieure agronomique de Toulouse [ENSAT]-Institut National Polytechnique (Toulouse) (Toulouse INP), Sol Agro et hydrosystème Spatialisation ( SAS ), Institut National de la Recherche Agronomique ( INRA ) -AGROCAMPUS OUEST, Institut National de la Recherche Agronomique ( INRA ) -AgroParisTech, Unité de Recherche Pluridisciplinaire Prairies et Plantes Fourragères ( P3F ), Institut National de la Recherche Agronomique ( INRA ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Agrosystèmes Cultivés et Herbagers ( ARCHE ), and Institut National Polytechnique [Toulouse] ( INP ) -Institut National de la Recherche Agronomique ( INRA ) -Ecole Nationale Supérieure Agronomique de Toulouse
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[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,symbiotic nitrogen fixation ,sol ,agriculture durable ,nitrogen efficiency ,système fourrager ,nitrogen balance ,légumineuse ,nitrogen ,arrière-effet ,soil ,système de culture ,[ SDV.SA ] Life Sciences [q-bio]/Agricultural sciences ,nitrogen fertilisation ,self-sufficiency ,azote ,[SDV.SA] Life Sciences [q-bio]/Agricultural sciences ,bilan d'azote ,soil fertility ,prairie ,legume ,fixation symbiotique de l'azote ,after-effects ,rotation culturale ,sustainable agriculture ,fertilité du sol ,fertilisation azotée ,efficacité de l'azote ,forage system ,crop system ,autonomie ,grassland ,france ,crop succession - Abstract
Intervention présentée aux Journées de l'AFPF, "La fertilité des sols dans les systèmes fourragers", les 8 et 9 avril 2015; Les atouts des légumineuses (fixation symbiotique, diversité fonctionnelle...) leur permettent de contribuer à la fertilité des sols, à l'amélioration de la durabilité de l'agriculture et de l'autonomie protéique des systèmes alimentaires. Il convient donc de mieux connaître leurs rôles, directs et indirects, dans les flux d'azote des rotations.Les légumineuses fourragères (en culture pure ou dans des couverts multispécifiques) représentent une grande part des apports azotés symbiotiques. Il existe une grande diversité d'implication des légumineuses dans les rotations. Des bilans d'azote du sol sont présentés pour plusieurs espèces de légumineuses ; ils varient selon de nombreux facteurs (type de couvert, autres sources d'azote...). Lorsque la fixation est active, elle peut représenter un apport d'une centaine d'unités d'azote. On connaît mieux maintenant les rôles, direct et indirect, des légumineuses dans les flux d'azote sous cultures et prairies (fixation, arrière-effets...) mais il faut poursuivre les recherches pour intégrer ces effets à l'échelle de l'exploitation (ou du territoire) et des rotations afin de développer des pratiques et systèmes de production productifs et durables.
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- 2015
285. Les facettes agroécologiques de l'élevage des ruminants en Afrique de l'Ouest et du Centre
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Vall, Eric, Diallo, Mohamadoun Amadou, Vigne, Mathieu, Bénégabou, Ida, Jonathan, Ba, Alassane, Dongmo, Aimé Landry, and Mélanie Blanchard
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Élevage extensif ,L01 - Élevage - Considérations générales ,agroécologie ,Pâturage ,Fertilité du sol ,Biomasse ,P01 - Conservation de la nature et ressources foncières ,Savane ,Écosystème - Published
- 2015
286. Erosion éolienne dans les régions arides et semi-arides africaines : processus physiques, métrologie et techniques de lutte
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Abdourhamane Toure, A. (ed.), Bergametti, G. (ed.), Bielders, C. (ed.), Bouet, Christel (ed.), Callot, Y. (ed.), Dupont, S. (ed.), Khatteli, H. (ed.), Labiadh, M.T. (ed.), Marticorena, B. (ed.), Rajot, Jean-Louis (ed.), and Valentin, Christian (ed.)
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METHODE D'ANALYSE ,FERTILITE DU SOL ,SURFACE DU SOL ,VENT ,SOL CULTIVE ,AEROSOL ,TRAVAIL DU SOL ,ENSABLEMENT ,ETAT DE SURFACE DU SOL ,MODELISATION ,EROSION EOLIENNE ,PRATIQUE CULTURALE ,ERODIBILITE DU SOL ,LUTTE ANTIEROSIVE ,CHANGEMENT CLIMATIQUE ,METHODE DE LUTTE ,DEPOT EOLIEN ,DEGRADATION DU SOL ,MESURE ,ANALYSE QUANTITATIVE - Published
- 2015
287. Legacy Effects of Different Land-Use Histories Interact with Current Grazing Patterns to Determine Grazing Lawn Soil Properties
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Olivier Bonnet, Adrian M. Shrader, Hervé Fritz, Joris P. G. M. Cromsigt, Hugo Valls Fox, Ecologie quantitative et évolutive des communautés, Département écologie évolutive [LBBE], Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), and Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
P33 - Chimie et physique du sol ,0106 biological sciences ,Soil texture ,[SDV]Life Sciences [q-bio] ,Herbage ,Parcours ,010603 evolutionary biology ,01 natural sciences ,Pâturage ,Grassland ,F01 - Culture des plantes ,Réserve naturelle ,Fertilité du sol ,Grazing ,Environmental Chemistry ,Propriété physicochimique du sol ,Savane ,Ecology, Evolution, Behavior and Systematics ,ComputingMilieux_MISCELLANEOUS ,2. Zero hunger ,Utilisation des terres ,geography ,geography.geographical_feature_category ,Ecology ,Land use ,Agroforestry ,L01 - Élevage - Considérations générales ,Lawn ,04 agricultural and veterinary sciences ,Vegetation ,15. Life on land ,Agronomy ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,P01 - Conservation de la nature et ressources foncières ,Rangeland ,Cycle du carbone - Abstract
Pastoralism and agriculture have affected rangeland ecosystems over the past millennia, including many ecosystems that are currently protected as reserves. However, the legacy of these land-use practices on current ecosystem functioning remains unclear. We studied legacy effects of former human land use on soil physical and chemical properties in a South African savanna. We did this by comparing soil properties in grazing lawns (patches of short grass maintained by the positive feedback between grazing intensity and forage quality) with the surrounding less grazed bunch grasslands within three different human land-use history contexts: (i) Abandoned bomas: permanent stone enclosures where livestock were kept overnight, and dung and urine accumulated for several years or decades. (ii) Old fields: areas where vegetation was cleared, soil tilled, and cultivated, but received little or no fertilization. (iii) Natural grasslands: not cultivated but grazed by livestock before the establishment of the reserve and wildlife thereafter. Former human land use rather than soil texture was the main determinant of grazing lawn location. Moreover, lawn soil properties also varied among land-use histories. In all grazing lawns, soil nutrient concentrations were higher than in adjacent grasslands but abandoned bomas contained three times more phosphorus, and twice as much nitrogen and carbon than old fields and natural grassland lawns. In addition to past land use, soil texture influenced lawn soil nutrients: Concentrations of phosphorus, potassium, calcium, magnesium, total nitrogen, and carbon in lawns were higher on clayey soils than sandy soils, whereas phosphorus, C:N ratio, and pH did not change with soil texture. Our study confirms previous findings on the effect of human land use on savanna heterogeneity, but also highlights how legacy effects may vary among different historic land-use practices.
- Published
- 2015
288. From farm scale synergies to village scale trade-offs: Cereal crop residues use in an agro-pastoral system of the Sudanian zone of Burkina Faso
- Author
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Pablo Tittonell, Marc Corbeels, Mélanie Blanchard, Eric Vall, Nadine Andrieu, Jonathan Vayssières, Innovation et Développement dans l'Agriculture et l'Alimentation (UMR Innovation), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), International Center for Tropical Agriculture [Colombie] (CIAT), Consultative Group on International Agricultural Research [CGIAR] (CGIAR), Systèmes d'élevage méditerranéens et tropicaux (UMR SELMET), Empresa Brasileira de Pesquisa Agropecuária (Embrapa), Ministério da Agricultura, Pecuária e Abastecimento [Brasil] (MAPA), Governo do Brasil-Governo do Brasil, Centre International de Recherche Développement sur l'Elevage en Zone Subhumide (CIRDES), Farming Systems Ecology, Wageningen University and Research [Wageningen] (WUR), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)
- Subjects
Résidu de récolte ,Crop residue ,010504 meteorology & atmospheric sciences ,F08 - Systèmes et modes de culture ,[SDV]Life Sciences [q-bio] ,west africa ,Compostage ,integration ,01 natural sciences ,nitrogen use efficiency ,nitrogen ,Productivité ,[SHS]Humanities and Social Sciences ,F01 - Culture des plantes ,spatial carbon ,Grazing ,Village ,fertility management ,crop-livestock ,2. Zero hunger ,flows ,U10 - Informatique, mathématiques et statistiques ,Agroforestry ,Fourrage ,soil fertility ,Gestion des déchets agricoles ,livestock systems ,04 agricultural and veterinary sciences ,PE&RC ,Geography ,conservation agriculture ,phosphorus budget ,Livestock ,Rangeland ,Modèle mathématique ,Conservation agriculture ,Pastoralism ,Zea mays ,Pâturage ,Petite exploitation agricole ,pratique agricole ,Fodder ,Fertilité du sol ,communal grazing ,[INFO]Computer Science [cs] ,west-african savanna ,0105 earth and related environmental sciences ,L02 - Alimentation animale ,Plante céréalière ,village territory ,business.industry ,P35 - Fertilité du sol ,Évaluation de l'impact ,Farm Systems Ecology Group ,Q70 - Traitement des déchets agricoles ,15. Life on land ,sub-saharan africa ,Utilisation ,Système agropastoral ,040103 agronomy & agriculture ,Exploitation agricole ,0401 agriculture, forestry, and fisheries ,Champ ,Animal Science and Zoology ,Soil fertility ,business ,Agronomy and Crop Science - Abstract
International audience; Traditionally, cereal crop harvest residues are communally grazed by the ruminant herds of villagers and transhumant pastoralists in the agro-pastoral systems which predominate in the savannah zone of West Africa. We analysed the impact of the private use of crop residues by individual farmers on crop and livestock productivity at three scales: the field, farm, and village. We collected data in the village of Koumbia, located in the Sudanian region of Burkina Faso. Three types of farmers were identified: resource-poor farmers, predominantly livestock farmers, and resource-rich farmers. The trade-offs between different uses and users of cereal crop residues at the three scales were analysed through field surveys and a simple model of biomass flows. We considered current communal use practices and two alternative scenarios of private cereal crop residue use: (i) for composting (fertility scenario) and (ii) as fodder (fodder scenario). Our analysis of current practices confirmed that farmers left around 80% of cereal crop residues on their fields. Soil fertility for cereal production therefore could be improved through crop residue management at the farm scale. We also found that communal grazing benefited farmers with high numbers of livestock. Maize grain production at the farm scale was improved in both of the simulated scenarios. Yet these scenarios had a negative impact on fodder self-sufficiency at the village scale, and on the N balance of the savannah-derived rangelands. The negative impact was greater in the fertility scenario than the fodder stock scenario. Increasing cereal productivity at the farm scale cannot be achieved without considering the trade-offs involved at the village scale. Changes in practices will require negotiations between the different types of farmers involved. Participatory innovation platforms with discussion support tools like the model presented in our study can facilitate such negotiations.
- Published
- 2015
289. Sols tropicaux - Pédologie
- Author
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Freycon, Vincent
- Subjects
P33 - Chimie et physique du sol ,Biologie du sol ,P34 - Biologie du sol ,forêt tropicale ,Sol tropical ,P32 - Classification des sols et pédogenèse ,Écologie forestière ,Pédologie ,Fertilité du sol ,K01 - Foresterie - Considérations générales ,Classification des sols ,Propriété physicochimique du sol - Published
- 2015
290. Tierras llaneras de Venezuela : tierras de buena esperanza
- Author
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Millan, F., Hétier, Jean-Marie, Lopez Falcon, R. (ed.), Hétier, Jean-Marie (ed.), Lopez Hernandez, D. (ed.), Schargel, R. (ed.), and Zinck, A. (ed.)
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DIAGNOSTIC ,FERTILITE DU SOL ,ANALYSE CHIMIQUE ,FERTILISATION DU SOL ,RELATION SOL PLANTE ,MANUEL - Published
- 2015
291. Maize crop residue uses and trade-offs on smallholder crop-livestock farms in Zimbabwe: Economic implications of intensification
- Author
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Mariana C. Rufino, Marc Corbeels, Mark T. van Wijk, Leonard Rusinamhodzi, and Ken E. Giller
- Subjects
Crop residue ,Résidu de récolte ,F08 - Systèmes et modes de culture ,Gross margin ,Soil management ,agriculture alternative ,Agricultural science ,Ecology ,Agroforestry ,U10 - Informatique, mathématiques et statistiques ,Prise de décision ,Aliment pour animaux ,PE&RC ,Simulation modeling ,Plant Production Systems ,Feed ,E16 - Économie de la production ,Livestock ,Fertilisers ,Conservation agriculture ,Biology ,Soil C ,Zea mays ,Petite exploitation agricole ,Crop ,Culture sous couvert végétal ,Matière organique du sol ,Fertilité du sol ,L02 - Alimentation animale ,business.industry ,Q70 - Traitement des déchets agricoles ,Modèle de simulation ,Analyse économique ,Agriculture ,Plantaardige Productiesystemen ,Utilisation ,Système agropastoral ,Animal Science and Zoology ,Soil fertility ,business ,Agronomy and Crop Science - Abstract
Decisions to use crop residues as soil cover for conservation agriculture create trade-offs for farmers who own cattle in crop-livestock systems. Trade-offs among soil C, crop and animal and crop productivity were analysed using the NUANCES-FARMSIM (FArm-scale Resource Management SIMulator) dynamic model. Retention on the soil surface of 0, 25, 50, 75 and 100% of the maize stover yield produced per farm, and the use of the remainder as animal feed was quantified over a 12 year period for four farm types in Murehwa, Zimbabwe. Retaining 100% maize residues in the field led to an annual loss of on average 68 and 93 kg body weight per animal for cattle on farms of the relatively wealthiest farmers (Resource Group, RG1) who had most land and cattle and RG2 respectively), and is therefore unsustainable for livestock production. There was an increase in grain yield of 1.6 t farm-1 and 0.7 t farm-1 for RG1 and RG2 respectively. Farmers without cattle (RG3 and RG4) may have a greater incentive for retaining their crop residues but they have to invest labour to keep the residues during the dry season. However, improved crop productivity for these farmers is limited by lack of access to fertiliser. The current practice of allocating all crop residues to animals results in average gross margin of US$7429 and US$4037 for RG1 and RG2 farmers respectively. Our results showed that from an economic perspective, it is logical that farmers prioritise the sustenance of cattle with crop residues over soil fertility management. We conclude that at current productivity levels, farmers who own cattle have limited scope to allocate crop residues for soil cover as it leads to significant loss in animal production and economic value.
- Published
- 2015
292. Sustainable management of soil in oil palm plantings
- Author
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Webb, Michael J., Nelson, Paul N., Cécile Bessou, Caliman, Jean-Pierre, and Sutarta, Edy Sigit
- Subjects
Fixation de l'azote ,Biologie du sol ,Symbiose ,Coffea ,Fertilisation ,Acidification ,Fertilité du sol ,Elaeis guineensis ,P34 - Biologie du sol ,Plantation forestière ,K10 - Production forestière ,Hevea brasiliensis ,Engrais minéral ,F04 - Fertilisation - Published
- 2015
293. Les sociétés rurales face aux changements climatiques et environnementaux en Afrique de l'Ouest
- Author
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Attané, Anne, Soumaré, M. A., Oumarou, A., Mazurek, Hubert, Sultan, B. and Lalou, Richard and Amadou Sanni, M. and Oumarou, A. and Soumaré, M.A., Laboratoire Population-Environnement-Développement (LPED), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU), Sultan, B. and Lalou, Richard and Amadou Sanni, M. and Oumarou, A. and Soumaré, M.A., Sultan, Benjamin (ed.), Lalou, Richard (ed.), Amadou Sanni, M. (ed.), Oumarou, A. (ed.), and Soumaré, M.A. (ed.)
- Subjects
CROYANCE ,CONSEQUENCE ECOLOGIQUE ,[SHS.GEO] Humanities and Social Sciences/Geography ,SAVOIR TRADITIONNEL ,[SHS.DEMO]Humanities and Social Sciences/Demography ,SYSTEME DE REPRESENTATIONS ,SYSTEME DD PRODUCTION ,ADAPTATION ,TEMPERATURE ,ComputingMilieux_MISCELLANEOUS ,SAISON HUMIDE ,PERCEPTION ,[SHS.ANTHRO-SE] Humanities and Social Sciences/Social Anthropology and ethnology ,FERTILITE DU SOL ,[SHS.DEMO] Humanities and Social Sciences/Demography ,[SHS.GEO]Humanities and Social Sciences/Geography ,[SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology ,ANTHROPOLOGIE SOCIALE ,EVOLUTION ,FAUNE ,PRATIQUE CULTURALE ,[SDE.BE] Environmental Sciences/Biodiversity and Ecology ,CLI ,CLIMAT ,PRECIPITATION ,CHANGEMENT CLIMATIQUE ,ENQUETE ,SOCIETE RURALE ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,ISLAM ,FLORE - Abstract
International audience; no abstract
- Published
- 2015
294. Opinion : point de vue d'un agronome pour une gestion durable des sols en Afrique de l'Ouest
- Author
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Dugué, Patrick
- Subjects
F08 - Systèmes et modes de culture ,Fertilisation ,Culture pluviale ,Histoire ,agriculture alternative ,Fertilité du sol ,Dégradation du sol ,conservation des terres ,F06 - Irrigation ,Irrigation ,P36 - Érosion, conservation et récupération des sols ,F07 - Façons culturales ,Intensification ,P35 - Fertilité du sol ,Gestion du sol ,Pratique culturale ,Développement durable ,Gestion des eaux ,Agroécosystème ,F04 - Fertilisation - Abstract
Chercheur au CIRAD, M. Dugué nous propose une analyse historique des approches de gestion durable des terres en Afrique de l'Ouest. Cet article présente le point de vue d'un agronome sur ce que pourrait être la gestion durable des sols sous cultures pluviales dans la région.
- Published
- 2015
295. Características químicas de um Gleissolo sob diferentes sistemas de uso, nas margens do rio Guamá, Belém, Pará
- Author
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Lopes, Elessandra Laura Nogueira, Fernandes, Antônio Rodrigues, Grimaldi, Catherine, Ruivo, Maria de Lourdes Pinheiro, Rodrigues, Tarcísio Ewerton, and Sarrazin, Max
- Subjects
CHIMIE DU SOL ,FERTILITE DU SOL ,Rio Guamá (PA) ,SYSTEME DE CULTURE ,MATIERE ORGANIQUE ,Sistemas de manejo do solo ,General Medicine ,Matéria orgânica ,Glaysoil ,Fertilidade ,Chemical characteristics ,Fertility ,Organic matter ,Gleissolo ,Características químicas ,UTILISATION DU SOL ,CIENCIAS EXATAS E DA TERRA [CNPQ] ,Soil handling system - Abstract
Foram estudados os efeitos do uso do solo sobre a fertilidade, em Gleissolo sob três diferentes sistemas de manejo. As coletas foram feitas antes do período chuvoso nos seguintes sistemas de manejo: área cultivada com arroz (Oriza sativa L.) há aproximadamente 40 anos, com algumas interrupções ao longo deste período, com o cultivo algumas vezes mecanizado e uso de aração e gradagem; área sob pastagem de canarana erecta lisa (Echinochloa pyramidalis Hitch.), formada há cerca de 20 anos sem uso de adubações ou calagens; e área sob vegetação natural de floresta típica das áreas de várzea alta. As amostras de solo foram coletadas em dez pontos a partir de um transecto nas áreas, em quatro profundidades 0-10, 10-20, 20-30 e 30-40 cm. Os resultados demonstraram que o solo em condições naturais, de modo geral, apresentou atributos químicos que variaram de bons a muito bons, o que demonstra um grande potencial para o uso agrícola. O cultivo agrícola dos solos das várzeas do rio Guamá provocou uma redução da concentração de P e de K. O sistema de uso com pastagem apresentou maior sustentabilidade da fertilidade do que o sistema sob cultivo com arroz, visto que, além da melhoria das características químicas, a matéria orgânica elevou-se, também, em relação ao sistema natural. The effect of the use of the soil on the fertility has been studied, in Gleyssoil under three different management systems. Collections had been made before the rainy period in the following handling systems: rice (Oriza sativa L.) plantation area, cultivated for approximately 40 years, with some interruptions in during this period. Some times the culture was mechanized, with use of plowshare and harrow; pasture area with plantation of canarana (Echinochloa pyramidalis Hitch.), cultivated for 20 years, without the use of fertilizers; and lowland area with natural vegetation. The samples of soil were collected in ten points, set by using the transect methodology, to four depths 0-10, 10-20, 20-30 and 30-40 cm in each point. The results demonstrate that the soil under natural conditions, presented chemical characteristics which insure to the soil a high potential for the agricultural use. The agricultural culture of the lowland soil in the Guamá River provoked a reduction in the concentration of P and K. The soil usage system with pasture presented better sustainability on it fertility than the system with rice cultivation, beyond the improvement of the chemical characteristics and raise in the organic matter concentration, when related to the natural vegetation system.
- Published
- 2006
296. Bois-énergie, exportation des minéraux et lien avec le pouvoir calorifique
- Author
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laurent saint-andre, Laurent Augusto, Nicolas Bilot, Jacques Ranger, Arnaud Legout, Unité de recherche Biogéochimie des Ecosystèmes Forestiers (BEF), Institut National de la Recherche Agronomique (INRA), Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), and CIRAD, INRA, BEF
- Subjects
ressource énergétique ,prélèvement d'elements mineraux ,[SDV]Life Sciences [q-bio] ,modèle ,pouvoir calorifique ,déchet végétal ,bois d'énergie ,fertilité du sol ,récolte du bois ,[SDE]Environmental Sciences ,élément minéral ,remanent ,france ,ComputingMilieux_MISCELLANEOUS - Abstract
National audience
- Published
- 2014
297. Legacy of logging roads in the Congo Basin: How persistent are the scars in forest cover?
- Author
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Kleinschroth, Fritz, Gourlet-Fleury, Sylvie, Sist, Plinio, Mortier, Frédéric, Healey, John R., Kleinschroth, Fritz, Gourlet-Fleury, Sylvie, Sist, Plinio, Mortier, Frédéric, and Healey, John R.
- Abstract
Logging roads in the Congo Basin are often associated with forest degradation through fragmentation and access for other land uses. However, in concessions managed for timber production, secondary roads are usually closed after exploitation and are expected to disappear subsequently. Little is known about the effectiveness of this prescription and the factors affecting vegetation recovery rate on abandoned logging roads. In a novel approach we assessed logging roads as temporary elements in the forest landscape that vary in persistence depending on environmental conditions. We analyzed road persistence during the period 1986–2013 in adjacent parts of Cameroon, Central African Republic and Republic of Congo. Three successive phases of road recovery were identified on LANDSAT images: open roads with bare soil, roads in the process of revegetation after abandonment and disappeared roads no longer distinguishable from the surrounding forest. Field based inventories confirmed significant differences between all three categories in density and richness of woody species and cover of dominant herbs. We used dead-end road segments, built for timber exploitation, as sampling units. Only 6% of them were identified as being re-opened. Survival analyses showed median persistence of four years for open roads before changing to the revegetating state and 20 years for revegetating roads before disappearance. Persistence of revegetating roads was 25% longer on geologically poor substrates which might result from slower forest recovery in areas with lower levels of soil nutrient content. We highlight the contrast amongst forests growing on different types of substrate in their potential for ecosystem recovery over time after roads have been abandoned. Forest management plans need to take these constraints into account. Logging activities should be concentrated on the existing road network and sites of low soil resource levels should be spared from business-as-usual exploitation.
- Published
- 2015
298. No to the “Eucalyptus War” in Madagascar!
- Author
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Bossanyi, Ilona, Aubréville, André, Bossanyi, Ilona, and Aubréville, André
- Abstract
A dispute has erupted in Madagascar between naturalists and the Water and Forests Service, on the subject of reforestation with eucalyptus. The matter specifically concerns the 3,000 hectares of plantations established since 1908 at Périnet, in a highly degraded forest invaded by bamboos, to supply fuelwood for railway engines. Yet this aversion for eucalyptus trees seems unwarranted given the convincing results of the trial plantations at Anamalazaotra, but also outside Madagascar, in Brazil, Kenya, Morocco and Ethiopia for example. Madagascar's capital, Tananarive, and its surroundings are now wooded thanks to the eucalyptus plantations (E. robusta, E. maculata) and their vigorous stump shoots that provide the local population with wood for cooking and construction. Eucalyptus plantations could also halt the erosion which is becoming widespread in Madagascar, particularly on the barren lavaka-scarred slopes of the Lake Alaotra basin. Madagascar's tree species are slow-growing, and eucalyptus has no equal for wood production. The use of eucalyptus can only be rejected for the purely sentimental reason that the species does not belong to the indigenous forest. Furthermore, in Madagascar's eastern forests, the climate is humid enough for an under-storey to develop and thus prevent erosion. Finally, it is to be deplored that naturalist societies should wish to challenge the one colonial service that is directly acting against for¬est destruction by listing certain areas for protection, fighting wildfires, protecting useful species and carrying out rehabilitation work. Attempting to discredit the forests service is ultimately harmful to the conservation of Madagascar's forests. Abstract adapted by the editorial team.
- Published
- 2015
299. Sustainable management of soil in oil palm plantings
- Author
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Webb, Michael J. (ed.), Nelson, Paul N. (ed.), Bessou, Cécile (ed.), Caliman, Jean-Pierre (ed.), Sutarta, Edy Sigit (ed.), Webb, Michael J. (ed.), Nelson, Paul N. (ed.), Bessou, Cécile (ed.), Caliman, Jean-Pierre (ed.), and Sutarta, Edy Sigit (ed.)
- Published
- 2015
300. Inheritance and QTL mapping of leaf nutrient concentration in a cotton inter-specific derived RIL population
- Author
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Liu, Shiming, Lacape, Jean-Marc, Constable, Greg A., Llewellyn, Danny, Liu, Shiming, Lacape, Jean-Marc, Constable, Greg A., and Llewellyn, Danny
- Abstract
Developing and deploying cotton cultivars with high nutrient uptake, use efficiency and tolerance to nutrient related soil stresses is desirable to assist sustainable soil management. Genetic variation, heritability, selection response and quantitative trait loci (QTLs) were investigated for five macronutrients (P, K, Ca, Mg, S) and five micronutrients (Fe, Mn, B, Zn, and Cu) in a recombinant inbred line (RIL) population from an inter-specific cross between Gossypium hirsutum cv. Guazuncho 2, and G. barbadense accession VH8-4602. Na and K/Na ratio were also studied as the imbalance between Na and other nutrients is detrimental to cotton growth and development. The concentrations of nutrients were measured for different plant parts of the two parents and for leaf samples of the whole population collected at early to peak flowering in field experiments over two years in a sodic Vertosol soil. Parental contrast was large for most nutrient concentrations in leaves when compared with other plant parts. Segregation for leaf nutrient concentration was observed within the population with transgression for P, K, K/Na ratio and all micronutrients. Genotypic difference was the major factor behind within-population variation for most nutrients, while narrow sense heritability was moderate (0.27 for Mn and Cu, and 0.43 for B). At least one significant QTL was identified for each nutrient except K and more than half of those QTLs were clustered on chromosomes 14, 18 and 22. Selection response was predicted to be low for P and all micronutrients except B, high for K, Na and B, and very high for K/Na ratio. Correlations were more common between macronutrients, Na and K/Na ratio where the nature and strength of the relations varied (r=-0.69 to 0.76). We conclude that there is sufficient genetic diversity between these two tetraploid cotton species that could be exploited to improve cotton nutrient status by introgressing species-unique favourable alleles.
- Published
- 2015
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