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To leverage agriculture's potential to better benefit both people and nature, policymakers need clear messages about which farming practices positively impact biodiversity and yields, and when trade-offs arise. Existing reviews analyse effects of different agricultural practices on either biodiversity or yield, without considering interactions. Here, we applied multinomial and quantile regression models to synthesize global evidence of synergies and trade-offs between biodiversity and yield, using 764 paired observations (from 43 studies across 18 countries) comparing diversified and simplified farming systems. Results show that farmland diversification led to win-win outcomes for biodiversity and yield in 23% of cases, while a win for biodiversity coupled with a loss in yield was the most likely outcome (28% of cases). Yield and biodiversity responses were negatively correlated, meaning that diversifying farming systems solely in pursuit of production goals is unlikely to lead to markedly better outcomes for biodiversity, or vice-versa. Yet certain situations made win-win significantly more likely, including when crop and animal production, or multiple diversification practices (e.g., intercropping and cover crops), were combined, when no agrochemicals were applied, when diversification occurred in temperate climates, and when diversification enhanced below-ground taxa. Win-win was also more likely than lose-lose when biodiversity was measured as richness or richness-evenness, but not abundance, suggesting that in certain contexts diversified farming can effectively enhance species diversity while increasing agricultural yields. Overall, crop commodity group and bioclimatic location were amongst the most important contextual factors influencing the likelihood of a synergy or trade-off between biodiversity and yield, and diversification that accounts for these is less likely to lead to unexpected outcomes. Our novel method and up-to-date review show that farmland diversification frequently leads to better outcomes for biodiversity and/or agricultural production when compared to monocultures and farmland stripped of natural vegetation, opening a pathway to more sustainable agricultural production.

Agroforestry (AF) is a promising land-use system to mitigate water deficiency, particularly in semi-arid areas. However, the belowground microbes associated with crops below trees remain seldom addressed. This study aimed at elucidating the effects of olive AF system intercropped with durum wheat (Dw), barely (Ba), chickpea (Cp), or faba bean (Fb) on crops biomass and their soil-rhizosphere microbial networks as compared to conventional full sun cropping (SC) under rainfed conditions. To test the hypothesis, we compared the prokaryotic and the fungal communities inhabiting the rhizosphere of two cereals and legumes grown either in AF or SC. We determined the most suitable annual crop species in AF under low-rainfed conditions. Moreover, to deepen our understanding of the rhizosphere network dynamics of annual crops under AF and SC systems, we characterized the microbial hubs that are most likely responsible for modifying the microbial community structure and the variability of crop biomass of each species. Herein, we found that cereals produced significantly more above-ground biomass than legumes following in descending order: Ba > Dw > Cp > Fb, suggesting that crop species play a significant role in improving soil water use and that cereals are well-suited to rainfed conditions within both types of agrosystems. The type of agrosystem shapes crop microbiomes with the only marginal influence of host selection. However, more relevant was to unveil those crops recruits specific bacterial and fungal taxa from the olive-belowground communities. Of the selected soil physicochemical properties, organic matter was the principal driver in shaping the soil microbial structure in the AF system. The co-occurrence network analyses indicated that the AF system generates higher ecological stability than the SC system under stressful climate conditions. Furthermore, legumes’ rhizosphere microbiome possessed a higher resilient capacity than cereals. We also identified different fungal keystones involved in litter decomposition and drought tolerance within AF systems facing the water-scarce condition and promoting crop production within the SC system. Overall, we showed that AF reduces cereal and legume rhizosphere microbial diversity, enhances network complexity, and leads to more stable beneficial microbial communities, especially in severe drought, thus providing more accurate predictions to preserve soil diversity under unfavorable environmental conditions. This research was carried out as part of the D4DECLIC Project, ARIMNet 2 Young Scientists Call 2017 (ERA-NET program), and Grant agreement no. 618127.

Sustainable field crop management has been considered to reach the food security issue due to global warming and water scarcity. The effect of deficit irrigation and nitrogen rates on quinoa yield is a challenging issue in those areas. In this regard, the interaction effects of different N rates (0, 125, 250, and 375 kg N ha−1) and irrigation regimes [full irrigation (FI) and deficit irrigation at 0.75 FI and 0.5 FI] on quinoa yield and water and nitrogen efficiencies were evaluated with a two-year field experiment. Increasing nitrogen fertilizer application levels from 250 to 375 kg N ha−1 under FI and deficit irrigation did not cause a significant difference in seed yield and the total dry matter of quinoa. Furthermore, 20% and 34% reductions were observed for nitrogen use efficiency (NUE) and nitrogen yield efficiency with the application of 375 kg N ha−1 compared with that obtained in 250 kg N ha−1 nitrogen fertilizer, respectively. Therefore, a Nitrogen application rate of 250 kg ha−1 and applying 0.75 FI is suggested as the optimum rate to reach the highest seed water use efficiency (0.7 kg m−3) and NUE (0.28 kg m−3) to gain 4.12 Mg ha−1 quinoa seed yield. Under non–limited water resource conditions, an FI and N application rate of 375 kg ha−1 could be used for higher seed yield; however, under water-deficit regimes, an N application rate of 250 kg ha−1 could be adequate. However, questions about which environmental factors impressively restricted the quinoa growth for optimizing the potential yield need further investigation.

International audience; Remote sensing observations such as normalized difference vegetation index (NDVI) trends can provide important insights into past and present land condition. However, they do not directly provide comprehensive information about our representation of land degradation and the processes at work. This study aimed to analyze vegetation productivity underlying factors in order to assess land degradation and to highlight the impact of definitions on its quantitative assessment, using Mozambique as case-study. Land productivity change were first analyzed using NDVI time-series (2000-2016), and a two-step framework was then used to understand the main factors of these productivity changes. The impact of land degradation's definition was assessed based on four types of stakeholder, with different priorities in terms of ecosystem services. The results show that 25% of the country display a significant land productivity decrease, while only 3% display a land productivity increase. A large part of these land productivity changes (>61% of the decrease, and >98% of the increase) is directly assigned to human activities, such as native forest growth or tree plantations (for the increase), or forest degradation, deforestation and loss of grassland productivity (for the decrease). We showed that the fraction of degraded land varies according to stakeholders' definitions, ranging from 12% to 20% of the Country, much less than the 39% estimated by Tier 1 United Nations Convention to Combat Desertification. This study provides a sound methodological framework for assessing land degradation status that could help stakeholders to design national and locally relevant land degradation mitigation policies or programmes.

International audience; Highlights:• Cocoa-based agroforestry systems were co-designed to increase their productivity and generated income.• Various participative tools were combined in an original co-design approach.• Innovations focused on diversity, density and spatial arrangement of crop species.• This co-design method is generic and can be applied to other complex systems.Abstract: Farmers constantly adapt cropping systems to meet their needs. Cocoa farming is frequently associated with low incomes and little access to technical innovations for the small farmers and their families who are responsible for most cocoa production around the world. A collaborative approach, including different professionals working in the Dominican cocoa sector, led to the emergence of many technical innovations designed to modify the current agroforestry systems (AFS) in order to increase their overall productivity while maintaining a high level of biodiversity. Two types of original results are presented: (i) the co-design method that combined different participatory tools drawn from the literature and (ii) the results of applying the method for the co-design of complex AFS in four working groups. Compared to current AFS, a first level of innovation that emerged during the workshops involves the diversity and density of associated crops in AFS. The second level of innovation deals with the evolution over time and location of the different species selected for the AFS plots. This participatory work led to the formulation of four AFS prototypes whose crop species and densities follow spatio-temporal dynamics anticipated to be capable of providing better revenues while maintaining a high level of crop biodiversity. The different technical and management innovations of these prototypes are described and discussed. The AFS prototypes resulting from the co-design process will be established on farm to assess their agronomic, ecological and economic performances.

Sustainable intensification seeks to increase outputs from existing farmland in ways that have a lower environmental impact. An extensive literature has examined the determinants of farmers' adoption of the different agro-ecological cropping systems needed to achieve these goals. However, the farmers' preferences for the attributes of these systems and the decision processes for choosing between available systems is still poorly understood. To fill this gap, this paper proposes a methodology that relies on a discrete choice experiment to analyse farmers' preferences for cropping systems and estimate the heterogeneity of decision processes among farmers. We modelled three major types of decision processes potentially used by farmers to evaluate the systems that are not consistent with the standard utility maximization framework. These findings offer insights into the behavioural patterns of respondents and should help crop system promoters and developers to better understand how their proposed systems are likely to be evaluated by different types of farmers.

International audience; Highlights:• The diversity of oil palm smallholders management practice and their performances remain poorly known.• We aim to understand which farming systems optimize the economic performance of oil palm.• A first typology on agricultural practices revealed a gradient of intensification, a second on economic performances revealed an optimum.• Crossing the two typologies showed that intensive practices are not economically optimal.• The study recommends to adapt local recommendations using multicriteria approaches.Abstract:CONTEXT: Oil palm is widely cultivated in Indonesia and it is produced by various populations of smallholders. Among those, ex-plasma smallholders are characterized by the fact that they only start to manage their own plantations 5 to 10 years after those were initially planted and managed by a partner industrial company. Despite the large areas that are cultivated by ex-plasma smallholders, their diversity of practices and economic performances are poorly quantified.OBJECTIVE: The present study aims at investigating which smallholder farming systems optimize profitability at the plot scale.METHOD: We defined two typologies, one based on agricultural practices and the other based on economic performance, using multivariate statistical analysis. The typologies were crossed to understand the links between agricultural practices and economic performance at the plot level.RESULTS AND CONCLUSIONS: Our results showed that despite initial plot homogeneity during planting phase, ex-plasma smallholders can develop very diversified management practices. A gradient of intensification was observed from farmers implementing no fertilization or weeding management up to farmers following agroindustrial-like management. Economic performances at the plot level was found to be variable, with gross margins ranging from 1.1 to 26.9 M IDR.ha−1.yr−1 (eq. 66.4 to 1625.5€). We showed that the most intensive practices led to highest yields although these were not linked to the optimal economic plot performances. A trade-off based on input costs was revealed, as high fertilization practices did not seem economically optimal for smallholders.SIGNIFICANCE: The present study highlights the need to combine quantified agronomic assessments with economic analysis, to properly design recommendations to farmers.

International audience; Extractive and agricultural resources do not have the same impact on poverty reduction and can compete with each other. We examine how extractive resource windfalls affect agricultural productivity, measured as the amount of output per worker in the agricultural sector. This is important since agricultural productivity is a key element of structural transformation and poverty reduction. To do this, we exploit a panel dataset of 38 countries over 1991-2016 and construct a country-specific commodity price index that captures resource-related gains and losses in aggregate disposable income. We find that an increase in the commodity price index leads to a drop in agricultural productivity in Sub-Saharan economies. Among the possible mechanisms to explain this result, our findings highlight the lack of spillovers across sectors and the low level of agricultural investment in autocratic regimes, both related to the exploitation of extractive resources. We also find that higher agricultural productivity is positively associated with the release of workers towards manufacturing and services, confirming its importance for structural transformation.; Les ressources extractives et agricoles n'ont pas le même impact sur la réduction de la pauvreté et peuvent se faire concurrence. Nous examinons comment les gains des ressources extractives affectent la productivité agricole, mesurée par la quantité de production par travailleur dans le secteur agricole. Cet aspect est important car la productivité agricole est un élément clé de la transformation structurelle et de la réduction de la pauvreté. Pour ce faire, nous exploitons un ensemble de données de panel de 38 pays sur la période 1991-2016 et construisons un indice des prix des produits de base spécifique à chaque pays qui saisit les gains et les pertes liés aux ressources dans le revenu disponible global. Nous constatons qu'une augmentation de l'indice des prix des produits de base entraîne une baisse de la productivité agricole dans les économies subsahariennes. Parmi les mécanismes possibles pour expliquer ce résultat, nos conclusions mettent en évidence l'absence de retombées entre les secteurs et le faible niveau des investissements agricoles dans les régimes autocratiques, tous deux liés à l'exploitation des ressources extractives. Nous constatons également qu'une productivité agricole plus élevée est associée de manière positive à la libération de travailleurs vers le secteur manufacturier et les services, ce qui confirme son importance pour la transformation structurelle.

Poor soil fertility and erratic rainfall constrain crop production in rain-fed smallholder farming systems in sub-Saharan Africa. Integration of drought tolerant and N2-fixing crops into maize-based cropping systems is a risk-averse strategy that also improves nitrogen cycling. A field experiment was carried out during the 2017/18 and 2018/19 cropping seasons in Goromonzi district in Zimbabwe. The trials were established on 14 farms, and on two field types (homefields and outfields), with eight treatments from a combination of cropping systems (maize and cowpea monocrops or maize/cowpea intercrops) and with or without nitrogen fertilizer (+N; -N). The trials were implemented on the same field plots for the two consecutive seasons. An improved cowpea variety and a landrace were used. The objectives were to determine 1) the productivity of the different cropping systems under variable soil fertility conditions, 2) N2-fixation of the two cowpea types when planted as monocrops or intercrops, and 3) mineral composition of maize and cowpea grains from intercrops and sole crops. Contrary to expected results, soil properties were not significantly different (P > 0.05) between field types. The land equivalent ratios (LER) were >1 for both seasons, implying improved land productivity under intercropping. Intercropping significantly reduced cowpea nodulation and active nodules, but not the total nodule weight, resulting in similar proportion of nitrogen derived from the atmosphere (%Ndfa) for cowpea grown as monocrop or in intercropping with maize. However, the total amount of fixed nitrogen was reduced in intercropping systems due to the smaller cowpea biomass compared to monocropping. Maize and cowpea grain mineral contents (Fe, Zn, Mn, Cu, Ca, Mg, P, K) were significantly affected by the cropping season only. We showed that intercropping maize with cowpea generally increases system productivity, in addition to substantial amounts of nitrogen being added to the system through N2-fixation. However, intercropping was not an agronomic biofortification option in these nutrient-depleted soils. Finally, annual variation in grain mineral quality can be larger than the annual variation in grain yield, potentially posing serious challenges to human nutrition.

Agriculture in West Africa is constrained by several yield-limiting factors, such as poor soil fertility, erratic rainfall distributions and low input systems. Projected changes in climate, thus, pose a threat since crop production is mainly rain-fed. The impact of climate change and its variation on the productivity of cereals in smallholder settings under future production systems in Navrongo, Ghana and Nioro du Rip, Senegal was assessed in this study. Data on management practices obtained from household surveys and projected agricultural development pathways (through stakeholder engagements), soil data, weather data (historical: 1980–2009 and five General Circulation Models, mid-century time slice 2040–2069 for two Representative Concentration Pathways, 4.5 and 8.5) were used for the impact assessment, employing a crop simulation model. Ensemble maize yield changes under the sustainable agricultural development pathway (SDP) were −13 and −16%, while under the unsustainable development pathway (USDP), yield changes were −19 and −20% in Navrongo and Nioro du Rip, respectively. The impact on sorghum and millet were lower than that on maize. Variations in climate change impact among smallholders were high with relative standard deviations (RSD) of between 14% and 60% across the cereals with variability being higher under the USDP, except for millet. Agricultural production systems with higher intensification but with less emphasis on soil conservation (USDP) will be more negatively impacted by climate change compared to relatively sustainable ones (SDP).

The quest for greater return on investment at short time is a recurring concern of the rubber industry. Early reverse tapping could be an option to this concern. It is therefore to verify this hypothesis that five different stages of initiation of upward tapping, 6th, 7th, 8th, 9th year and the control in 10th year, with application of 2.5 and 5% ethephon was conducted for eight years in the South-East (Bettie) and the Centre-West (Gagnoa) of Cote d'Ivoire. Irrespective of the ethephon concentration used, average yield obtained from upward tapping at 6th year was 3012 ± 516 kg ha-1 y-1 against 2528 kg ha-1 y-1 in the control, where controlled upward tapping started at 10th year with a productivity gain of 19%. The mean annual increase in circumference in the upward tapped trees at 6th year, was 3.02 ± 0.18 cm y-1 and statistically higher than that of the control treatment (2.40 cm y-1). Physiological profiles improved during the experiment, regardless of site and of periods of upward tapping. Generally, the sensitivity to panel dryness in the control is more pronounced than that of early upward tapping. Our results suggest very early upward tapping at 6th year after the 5 years of downward tapping, is the best period to harvest latex from the high tapping panel.

Diese Arbeit analysiert das Wachstum der landwirtschaftlichen Produktivität durch Innovationen in der Landwirtschaft und schätzt seine uswirkungen auf die nichtlandwirtschaftliche Beschäftigung in Afrika Subsahara. Anwendung der SFA-Methode Die durchschnittliche jährliche Wachstumsrate wird über den gesamten Zeitraum auf 1,9% geschätzt; und 3,13% im letzten Jahrzehnt hauptsächlich angetrieben durch technische Veränderungen. Unter den zunehmenden Innovationen Einfluss von Ertrag, Kali, Harnstoff und Bewässerungssystemen positive und signifikante Steigerung der landwirtschaftlichen Produktivität. Diversifikation Kulturen als gewinnbringende Innovationen wirken sich positiv aus und signifikant für die Produktivität. Die Ergebnisse unseres Panel-VAR-Modells ermöglichen Gewährleistung eines einseitigen Kausalzusammenhangs mit der landwirtschaftlichen Produktivität in Richtung nichtlandwirtschaftliche Beschäftigung. Und Kausalität funktioniert nur aus Produktivität in Richtung Ungleichheit. Die gesteigerte landwirtschaftliche Produktivität führt daher zu einer Steigerung von nichtlandwirtschaftliche Beschäftigung und erhebliche Ungleichheiten bei der Einkommensverteilung, aber notwendig für das Wachstum von Investitionen. GMM führt zum System Mit der FOD-Transformation können wir die Verteilung von identifizieren Umsatz und Produktpreis ändern sich als Hauptkanäle durch die das Wachstum des Agrarsektors das Beschäftigungsniveau in diesem Sektor beeinflusst nichtlandwirtschaftlich. Für ein nachhaltiges Produktivitätswachstum undAbbau entlassener Arbeitsplätze im afrikanischen Agrarsektor, die Auswirkungen von Fokus auf Verbesserung des Produktionssystems und Spezialisierung Arbeit., This thesis aims at analyzing agricultural productivity growth through innovations in agriculture and estimate its impact on off-farm employment in Sub-Saharan Africa. Applying the Stochastic Frontier Analysis (SFA) on historical crop production data, we find the average growth rate of agricultural productivity estimated at 1.9% per year for the entire period ; and at 3.13% this last decade mainly led by technical change. Scale efficiency change has been the major barrier to TFP growth in the African agriculture. Potash fertilizer, urea, and irrigation systems have a positive and significant influence on agricultural productivity growth as far as yield-increasing innovations are concerned. Crop diversification, as profit-enhancing innovations, has a positive and significant effect on agricutural productivity growth. The results of the panel VAR model depict a causal relationship with single direction from agricultural productivity to off-farm employment. Between agricultural productivity and inequalities, causality functions from productivity to inequalities. Therefore, productivity growth generates an increase of off-farm employment and significant inequalities in the distribution of income, but necessary to investments growth in agricultural sector. The results of GMM system with the FOD transformationallow us to identify, income distribution and product price change as the main channels through which agricultural growth affects the off-farm employment level. To address slow productivity growth and redundant jobs in the African agriculture, policies implications are oriented towards improvement of agricultural production system and labor specialization., Cette thèse analyse la croissance de la productivité agricole à travers les innovations en agriculture et estime son impact sur l’emploi non-agricole en Afrique Sub-Saharienne. Appliquant la méthode SFA, Le taux de croissance annuel moyen est estimé à 1,9% sur toute la période ; et de 3,13% cette dernière décennie principalement conduit par le changement technique. Parmi les innovations augmentant le rendement, l’engrais potasse, l’urée, et les systèmes d’irrigation ont une influence positive et significative sur l’accroissement de la productivité agricole. La diversificationdes cultures, comme innovations augmentant le profit, a un effet positif et significatif sur la productivité. Les résultats de notre modèle VAR en panel permettent de s’assurer d’une relation causale à sens unique de la productivité agricole vers l’emploi non-agricole. Et la causalité fonctionne uniquement de la productivité vers les inégalités. D’où, le surcroit de productivité agricole engendre une hausse de l’emploi non-agricole et des inégalités importantes dans la répartition des revenus, mais nécessaire à la croissance des investissements. Les résultats des GMM en systèmeavec la transformation FOD nous permettent d’identifier, la distribution des revenus et le changement des prix des produits comme étant les principaux canaux par lesquels la croissance du secteur agricole affecte le niveau de l’emploi du secteur non-agricole. En faveur d’une croissance soutenue de la productivité et d’une réduction de l’emploi superflu dans le secteur agricole africain, les implications de politique sont axées sur l’amélioration du système de production et la spécialisation du travail.

CONTEXT Climate change and variability have been identified as major threats to key sectors such as agriculture that drive economic growth and sustainable development in developing countries. The provision of tailored weather and climate information services (WCIS) that meet users' expectations can play an important role in helping decision makers adapt to and mitigate the effects of climate change and climate However, the evidence base showing the benefits of WCIS is still thin. OBJECTIVE This study analyzes the impact of uptake of tailored seasonal and daily weather forecasts that are mediated by a multidisciplinary working group (MWG) on crop productivity and household income of smallholder farmers in Senegal. METHODS A two-season balanced dataset in combination with panel econometrics was used to explore the impact of uptake of weather and climate information on crop income for farmers in Senegal. The data were complemented by participatory surveys that provide richer contextual information to explain the causal pathways that link farmers' uptake with increased crop income for farmers with access to the MWG. RESULTS AND CONCLUSIONS Results show that the use of weather and climate information increased the value of crop produce by between 10 and 25% for farmers with access to an MWG. Coordinated platforms that involve diverse stakeholders like the MWGs play a critical role in co-producing weather and climate information that are more usable to farmers, thereby improving uptake and livelihoods. The impact pathways and implications for policy are discussed. SIGNIFICANCE This study expands the limited evidence base on the role of weather and climate services in improving the livelihoods of smallholder by (i) going beyond the use of cross-sectional and using longitudinal data, (ii) analyzing causal impacts on farmer's livelihoods, i.e., crop yields and household income and (iii) using participatory approaches to better explain the causal impact pathways.

Optimal use of resources in agroforestry requires the evaluation of multi-species and multi-strata cropping systems. The current study evaluated the effect of plant diversity on the performance of agroforestry systems in Talamanca, Costa Rica. Plants in nine 100-m2 plots in each of 20 fields were classified into five groups (banana, cacao, other fruits, timber, and firewood), and diversity was assessed by the Shannon–Wiener index. The production of each individual plant was estimated and converted into income according to local market prices. Our results indicated that as plant diversity increased, the income derived per plant increased for other fruits, firewood, and timber and also when all cultivated plants were considered as one group. In contrast, the income derived per plant decreased for banana and cacao as diversity increased. This suggests that complementarity between plants was stronger than competition for those plants occupying the higher strata of the canopy (i.e., other fruits, firewood, and timber) but that competition was stronger than complementarity for plants occupying the lower strata of the canopy (i.e., banana and cacao). These results increase our understanding of how the composition and the organisation of these agroforestry systems may be optimized.

This report presents the results of an impact analysis of several scenarios related to the Agricultural Commercialization Cluster (ACC) initiative. This initiative was introduced by the Government of Ethiopia during the first Growth and Transformation Plan (2010-2015) as a mechanism to improve agricultural productivity and production within specific geographies by targeting a limited number of high-value commodities. The farm-household model FSSIM-Dev (Farm System Simulator for Developing Countries) is applied to a representative sample of 2,886 individual farm-households spread throughout the country, taken from the 2013/14 Ethiopia Socioeconomic Survey. Simulation results show that upscaling the ACC productivity performance to the respective regions would lead to an increase in production of the main products ranging between 1.8% and 62.6%, depending on scenario, region and commodity. The average (across all ACC scenarios considered) country-level production increase for wheat, teff, maize and barley are assessed to be 29.6%, 21.1%, 12.8% and 12.6%, respectively. These impacts are driven by the rise in land productivity, rather than area expansion (through putting fallow land into cultivation) and/or area reallocation. The increase in crop yields would also have a positive impact on both income and poverty level of farm households. The average increase in gross income at the country and individual farm-household levels are assessed to be around 14% and 9%, respectively. These impacts could be more pronounced for individual farms: for example, 85% of the farms would experience an increase in gross income of up to 17% to 32%, depending on the nature of scenarios considered. The largest income change occurs in farms specializing in field crops, and in medium-large farms (i.e. farms with total production value of larger than ETB 9,000). The increase in both production and income would also raise food consumption and improve nutritional indicators., JRC.D.4-Economics of Agriculture

Crop biodiversity has the potential to enhance resistance to strains due to biotic and abiotic factors and to improve crop production and farm revenues. To investigate the effect of crop biodiversity on crop productivity, we build a probabilistic model based on ecological mechanisms to describe crop survival and productivity according to diversity. From this analytic model, we derive reduced forms that are empirically estimated using detailed field data of South African agriculture combined with satellite derived data. Our results confirm that diversity has a positive and significant impact on crop survival odds. We show the consistency of these results with the underlying ecologic and agricultural mechanisms.; La biodiversité des cultures permet d'accroître leur résistance aux attaques dues à des facteurs biotiques et abiotiques, et d'améliorer la production et les revenus des exploitations agricoles. Pour étudier l'effet de la biodiversité des cultures sur leur productivité, nous construisons un modèle probabiliste basé sur des mécanismes écologiques. De ce modèle analytique, nous dérivons des formes réduites qui sont estimées empiriquement à l'aide de données de terrain de l'agriculture sud-africaine combinées à des données satellites. Nos résultats confirment que la diversité a un impact positif et significatif sur les cultures. Nous montrons la cohérence de ces résultats avec les mécanismes écologiques et agricoles sous-jacents.

CONTEXT: Livestock farming is a major factor in the balance or disruption of bio-geochemical cycles, climate and biodiversity. The Brazilian Amazon is emblematic of these tensions between livestock production and environment. Extensive cattle production has spearheaded the territorial conquest of this region for more than 50 years, and is the main cause of deforestation. The intensification of animal production is presented as a success factor for long-term maintenance of low deforestation and a good level of production. Yet in reality there is no guarantee of this outcome, and very few studies focus on quantifying the effective intensification of the Amazonian livestock sector, and its impact on deforestation. OBJECTIVE: The objective of our article is to characterize and discuss the evolution of livestock farming in Paragominas (Brazil). This municipality is presented as an example of sustainable agrarian transition in the Amazon. After several decades with one of the highest rates of Amazon deforestation, Paragominas reduced its annual deforestation rate tenfold between 2005 and 2012. METRHODS: We analyse the livestock sector, using the method of territorial metabolism. The first step consisted in making an inventory of all material flows and all areas used either directly or indirectly by livestock farming. We calculate productive and environmental indicators' trends from 1990 to 2012 (intensity, production, efficiency, self-sufficiency, deforestation and N surplus). RESULTS AND CONCLUSIONS: We observe an extensive farming system with low density (between 0.47 and 0.83 LU/ha), low production (between 0.97 and 1.48 kg N/ha/year), low efficiency, but a large degree of self-sufficiency (exceeding 95%), and very low N surplus per hectare (between 14 and 16 kg N/ha/year). Ruminants account for 98% of all Livestock Units (LU) and over 95% of animal production. The selected indicators to characterize the intensity of farming systems are divergent: indicators expressed per unit area show extensification, with a decrease in animal density, inputs per ha and a stabilization of production per ha. However, production per animal unit and livestock efficiency increase across the study period. SIGNIFICANCE: The increase in animal production and efficiency was not related to the decrease in deforestation. The increased oversight of land use, along with strict policies, enabled the cessation of deforestation, but this did not result in the intensification of livestock farming for the moment. Our study shows that there is significant potential to increase livestock production and efficiency.

Coffee is a key export commodity of East Africa, but average smallholders' yields are low. To guide sustainable yield improvements of smallholders' coffee systems, we investigated coffee yield components in three different types of coffee cropping systems along an altitude gradient (1100−2100 m.a.s.l.) during two production years (2015 and 2016). We selected 810 coffee trees distributed over 27 farms and monitored number of stems per tree, fruit load per branch, productive nodes per branch (on four branches of one stem per tree) and number of productive branches per stem (on one stem per selected tree) in both years. Additionally, we monitored productive stems per ha, coffee tree density and cherry weight in combination with pest and disease occurrence and management information from interviews. Coffee farms were classified as Coffee-Open (CO) (< 20 % shade cover), Coffee-Banana (CB) (coffee dominantly intercropped with bananas) or Coffee-shade Tree (CT) (coffee dominantly intercropped with shade trees). Coffee-Banana had larger yield per ha (green bean kg ha−1) (1086±736 kg ha−1) and yield per stem (green bean kg stem−1) (0.24±0.16 kg stem−1) than CO (670±457 kg ha−1 and 0.21±0.26 kg stem−1) and CT (428±259 kg ha-1 and 0.10±0.12 kg stem−1). Fruit loads, productive nodes, productive branches and cherry weight declined with shade cover, especially for shade cover>30 %. Additionally, the same yield components correlated negatively with number of stems per tree. Fertilizer and fungicide use were related to more productive branches and cherry weight respectively, and stem borer was identified as the most important pest in this area. Our results suggest that yield in the region could be increased, i) by maintaining shade at an intermediate level, particularly at low and mid altitude and by reducing the number of stems per coffee tree (< 4), and ii) by improving soil fertility and protection against pest and disease.

Made available in DSpace on 2020-12-10T20:01:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01. Added 1 bitstream(s) on 2021-07-15T15:25:04Z : No. of bitstreams: 1 S1980-50982020000100117.pdf: 1255717 bytes, checksum: cb32f05c60784ed1d46889ded03b66f3 (MD5) Anglo American Arauco Arborgen ArcelorMittal Cenibra CMPC Copener Duratex Eldorado Fazenda Campo Bom Fibria Florestal Itaquari Forestal Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo - Brazil State University of Sao Paulo - Brazil Federal University of Lavras - Brazil Federal University of Rio Grande do Norte - Brazil Colorado State University - USA North Carolina State University - USA USDA Forest Service Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The present study aimed to evaluate the correlations between productivity and eucalyptus drought (DR) response between soil attributes in two distinct climatic types in Brazil. For this, 24 experiments were installed in Brazil with four common clones in all the experiments to obtain strong edaphoclimatic contrasts, and, thus, to measure the productivity and the response to drought and to describe its relationship with the attributes of the soils. Two climatic groups were evaluated: Wet (precipitation rate: evapotranspiration between 1.0 to 2.5) and Sub-Humid (precipitation rate: evapotranspiration between 0.5 to 1.0). The attributes of the evaluated soils were: Sand, Silt, Clay, organic matter (O.M.), cation exchange capacity (CEC). For sites located in the wet climate class, CVWB correlated negatively with O.M. and clay, and positively with the sand. For DR, the correlations were observed for the Sub-Humid climate for the CEC and Sand variables, and for the Humid climate, no correlations were observed between the attributes of soils with DR. Univ Estadual Paulista, VIMEF Solucoes Florestais, Av Brasil Sul 56, BR-15385000 Ilha Solteira, SP, Brazil Univ Estadual Paulista, Dept Fitossanidade Engn Rural & Solos, Fac Engn Ilha Solteira, Av Brasil Sul 56, BR-15385000 Ilha Solteira, SP, Brazil Univ Montpellier, Montpellier SupAgro, Eco & Sols, CIRAD,INRA,IRD, 389 Ave Agropolis, F-34980 Montpellier, France Univ Estadual Paulista, Dept Ciencias Exatas, Fac Ciencias Agr & Vet, Campus Jaboticabal, BR-14884900 Jaboticabal, SP, Brazil Eldorado Brasil Celulose, BR-158,Km 231 S-N, BR-79641300 Tres Lagoas, MS, Brazil Univ Estadual Paulista, VIMEF Solucoes Florestais, Av Brasil Sul 56, BR-15385000 Ilha Solteira, SP, Brazil Univ Estadual Paulista, Dept Fitossanidade Engn Rural & Solos, Fac Engn Ilha Solteira, Av Brasil Sul 56, BR-15385000 Ilha Solteira, SP, Brazil Univ Estadual Paulista, Dept Ciencias Exatas, Fac Ciencias Agr & Vet, Campus Jaboticabal, BR-14884900 Jaboticabal, SP, Brazil

The rapid expansion of the Inca from the Cuzco area of highland Peru (ca. AD 1400–1532) produced the largest empire in the New World. Although this meteoric growth may in part be due to the adoption of innovative societal strategies, supported by a large labour force and a standing army, we argue that it would not have been possible without increased crop productivity, which was linked to more favourable climatic conditions. Here we present a multi-proxy, high-resolution 1200-year lake sediment record from Marcacocha, located 12 km north of Ollantaytambo, in the heartland of the Inca Empire. This record reveals a period of sustained aridity that began from AD 880, followed by increased warming from AD 1100 that lasted beyond the arrival of the Spanish in AD 1532. These increasingly warmer conditions would have allowed the Inca and their immediate predecessors the opportunity to exploit higher altitudes (post-AD 1150) by constructing agricultural terraces that employed glacial-fed irrigation, in combination with deliberate agroforestry techniques. There may be some important lessons to be learnt today from these strategies for sustainable rural development in the Andes in the light of future climate uncertainty.