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Agroforestry is often seen as a sustainable land-use system for agricultural production providing ecosystem services. Intercropping with food crops leads to equal or higher productivity than monoculture and results in food production for industry and subsistence. Low rubber price and low labor productivity in smallholdings have led to a dramatic conversion of rubber plantations to more profitable crops. The literature analysis performed in this paper aimed at better understanding the ins and outs that could make rubber-based agroforestry more attractive for farmers. A comprehensive search of references was conducted in March 2023 using several international databases and search engines. A Zotero library was set up consisting of 415 scientific references. Each reference was carefully read and tagged in several categories: cropping system, country, main tree species, intercrop type, intercrop product, level of product use, discipline of the study, research topic, and intercrop species. Of the 232 journal articles, 141 studies were carried out on rubber agroforestry. Since 2011, the number of studies per year has increased. Studies on rubber-based agroforestry systems are performed in most rubber-producing countries, in particular in Indonesia, Thailand, China, and Brazil. These studies focus more or less equally on perennials (forest species and fruit trees), annual intercrops, and mixed plantations. Of the 47 annual crops associated with rubber in the literature, 20 studies dealt with rice, maize, banana, and cassava. Agronomy is the main discipline in the literature followed by socio-economy and then ecology. Only four papers are devoted to plant physiology and breeding. The Discussion Section has attempted to analyze the evolution of rubber agroforestry research, progress in the selection of food crop varieties adapted to agroforestry systems, and to draw some recommendations for rubber-based agroforestry systems associated with food crops.

Weeds are a major threat in tropical regions where climate conditions favor their growth and development. This is particularly true in low-input rice-based cropping systems in the Malagasy highlands, where weed management is mainly done by manual removal. Crop rotation is often promoted as an efficient way to control weed infestations, while the role of fertilization is more controversial. In this study, we compared rice monoculture to three rainfed rice-based two-year rotations: rice followed by groundnut, rice followed by sorghum-cowpea mixture, and rice followed by a velvet-bean crotalaria mixture. Each rotation was tested with two levels of fertilization (5 t DM ha−1 organic manure, sole or in combination with mineral fertilizer - 400 kg ha−1 NPK + 200 kg ha−1 urea). We assessed the effect of rotation and fertilization on weed composition, diversity, biomass and rice yield. Additionally, the farmers' perception of weed harmfulness and the relation between their assessment of weed harmfulness and rice production was tested. Our results showed that weed biomass significantly decreased rice yield but only under the low fertilization level. The rotation of rice with the velvet bean-crotalaria mixture was efficient in reducing weed biomass, modified weed community composition and allowed to achieve the highest rice yield. A significant negative relationship was found between weed community harmfulness index and weed species richness. Yet, the lowest rice yield was observed under rice monoculture despite a higher species richness over years and under high fertilization level. The lack of significant correlation between the harmfulness index and the actual rice yield is probably because our index is partly based on farmer's perception, and only on major weeds. More studies on tropical weed harmfulness are needed to support the design of ecologically intensified cropping systems.

Access to AdvenAlg is via the URL address: www.wikwio.org/alg/ which currently allows the identification of 125 important species of algerian weeds in field crops. They are divided according to their noxiousness into 15 agronomically major species, 20 secondary species, and 90 minor species. This modern computer-assisted identification (CAI) method allows simple and precise identification of plant species based on illustrated characters (and not described by botanical jargon as is the case with classic dichotomous keys), therefore in a graphic manner, by creating a composite portrait of the plant. Emphasis is placed on vegetative characters to enable recognition of incomplete samples. A composite portrait of the plant is created using a process allowing the free choice of characters, error management, the absence of technical terminology and self-correction. At any time, it is possible to access macro photographs and descriptive texts and print them. The AdvenAlg database, available in French or English, will be gradually updated with other species of crop weeds from the same phytogeographic region. All AdvenAlg species sheets can also be consulted on the Wiktrop collaborative portal dedicated to the sharing and dissemination of knowledge on weeds in tropical and Mediterranean crops: http://portal.wiktrop.org.

Les transformations récentes de l'agriculture au Vietnam, suivants des objectifs de croissance économique nationaux portés par le développement du secteur agricole, affectent l'existence des systèmes mixtes de polyculture-élevage traditionnellement présents dans les territoires montagneux du Nord-Ouest Vietnam. L'intégration culture-élevage (ICE) dans les systèmes mixtes diversifiés présente de nombreux intérêts et pourrait constituer un levier d'intensification de la production et du développement durable de l'agriculture au Vietnam. Nous cherchons dans ce travail de thèse à évaluer les contributions de l'ICE et de la diversification des systèmes agricoles aux performances et au développement durable des fermes dans un contexte de spécialisation au Vietnam. Dans ce but, nous avons suivi une approche méthodologique en trois axes visant à (i) comprendre la diversité des formes d'ICE et de diversification au niveau des exploitations et du territoire, puis à (ii) co-construire des scénarios d'évolution des systèmes et des pratiques agricoles à l'échelle des exploitations et des territoires, à partir des trajectoires des exploitations et en mobilisant une démarche participative et prospective, enfin à (iii) concevoir et utiliser un modèle, afin d'évaluer les performances des formes actuelles et futures d'ICE et leurs contributions au développement durable des systèmes d'exploitation. Une typologie des exploitations du District de Ðiện Biên situé dans le Nord-Ouest Vietnam a mis à jour sept types d'exploitations selon leur niveau d'ICE et de diversification de leurs activités. Cinq scénarios des futurs possibles des systèmes agricoles envisageant les évolutions de structures et de pratiques des exploitations à vision 2037 ont été construits avec les acteurs locaux. Leurs effets sur les performances des types d'exploitations identifiés ont été simulés à l'aide d'un outil de modélisation. Les résultats montrent que l'ICE peut contribuer à améliorer les performances environ

Intercropping, i.e., growing several species in the same field for a major part of their growing periods, often improves yield and weed control, but their performance greatly varies across situations. The aim of this study was to evaluate the effects of bi-species legume–cereal intercrops on weed dynamics and their impact on crop production, in the absence of nitrogen or water stress, via simulations with FlorSys. This individual-based 3D model simulates daily crop–weed seed and plant dynamics over the years, from cropping system and pedoclimate, focusing on competition for light. The study tested seven species proportions in two species mixtures (wheat–faba bean and barley–pea) and nine spatial sowing patterns in three species mixtures (triticale–faba bean, wheat–faba bean, wheat–pea), in both cases comparing the intercrops with the corresponding sole crops (controls). Intercrops and controls were inserted into rotations and simulated over 30 years and repeated with 10 climate scenarios from South-Western France, either with or without weeds. The simulations showed that: (1) the intercrops that best controlled weeds were barley–pea and triticale–faba bean, (2) the spatial pattern alternating one cereal row with one legume row as well as the 67 %-cereal–33 %-legume and 100 %-cereal–50 %-legume species proportions were those that maximised yields and minimised losses due to weeds, (3) the weed biomass in intercrop was greater than or equal to that of the sole cereal, and less than that of the sole legume, and (4) legumes benefitted more from intercropping than cereals because cereals are more competitive against weeds. Intercrop yield was best when combining species with contrasting shading responses (etiolated with stockier plants, leafy with stemmier plants) but early and good plant emergence was essential, particularly for weed suppression.

The determination of changes in soil organic carbon (SOC) content under different cropping systems is necessary for policy development oriented towards soil conservation, C sequestration, and future C credit markets. The aim of this study was to generate an open SOC dataset resulting from a systematic literature search related to the agricultural systems for Southeast Asia. The dataset has 209 articles and 4341 observations on soils of cropping systems in this region from articles published between 1987 and 2023. This dataset included different management practices, land uses, soil sampling depth, and length of SOC content assessment. In addition, inherent features of crop production reported in the experiments were included in the dataset. This dataset can be applied to quantify and compare the impact of different land uses or management practices on SOC content, providing foundational knowledge towards identifying sustainable practices. Lastly, it is a useful guide for future regional SOC sequestration policies and the development of C credit markets.

Dans le gouvernorat de Kébili au sud de la Tunisie, les zones irriguées se sont fortement développées ces 30 dernières années. Le système oasien traditionnel, fondé sur des cultures organisées sur trois étages et sur les complémentarités entre agriculture et élevage, a été fragilisé. De nombreux agriculteurs se sont limités à la production de dattes, à la fois dans les oasis traditionnelles et dans les nouvelles zones irriguées. Le présent article mesure l'influence de la disponibilité en eau et de différents facteurs relatifs aux orientations des agriculteurs, sur leur décision de mettre en oeuvre des pratiques agricoles écologiquement intensives. Les principales pratiques étudiées sont la culture d'arbres fruitiers sous les palmiers et l'utilisation du fumier comme fertilisant. Cinquante agriculteurs, qui ont obtenu au début des années 2000 la gestion de terres agricoles dans la municipalité de Jemna, ont été interrogés. La disponibilité en eau est un facteur majeur facilitant les pratiques écologiquement intensives. Ces pratiques sont aussi favorisées par le fait que le revenu familial soit avant tout tiré de la parcelle dans la zone d'étude. Un autre facteur important est l'intérêt pour une gestion durable de l'exploitation agricole – au contraire d'une gestion visant une rentabilité à court terme. Des agriculteurs de Kébili, qui veulent faire de l'agriculture un projet économique et un projet de vie, sont ainsi prêts à mettre en oeuvre des pratiques écologiquement intensives. La baisse de l'agrobiodiversité observée dans les oasis traditionnelles du Sud tunisien n'est pas inéluctable, si l'accès à l'eau est amélioré et si de tels projets de vie fondés sur l'agriculture sont plus aisément réalisables.

Annual global coffee consumption growth (1–2%) has been largely met (>50%) mainly by Brazil and Vietnam through high-input monocrop system adoption. Smallholders account for >80% of global producers and >60% of global supply despite limited farm sizes (<2 ha), yields, and input usage. Production concentration in areas with high-yielding systems has fulfilled global demand growth while keeping coffee prices low. However, climate shocks demonstrate the vulnerability of all supply models, strengthening the voice of those advocating more resilient and diversified systems. We review current agroforestry knowledge to identify key trade-offs and synergies between sustainability/performance indicators (i.e. economic, environmental, and social) and explore pathways for a more sustainable coffee future with three examples representative of global coffee production system diversity.

The objective of the ACME (Agile Crop Model Ensemble) software is to facilitate the simulation of large virtual experiments using an ensemble of crop models on personal computers running Windows OS. These simulations can either be point-based or spatially explicit. The package includes an ensemble of three crop models (executable files and input and output data) and two databases: 'MasterInputOutput' which contains the input and output variables of the models, and 'ModelDictionary', which contains the connections and required transformations between variables of the different models. In addition, an executable code 'DataMill' applies these transformations and manages the data flow between the MasterInputOutput database and the file system of each model, before (input parameters) and after (output parameters) running the virtual experiment.

he slow increase in grain production in sub-Saharan Africa (SSA) is largely the result of cropland expansion rather than an increase in crop yields, which have been stagnantly low (< 1.5 t ha-1). Sustainable intensification of crop production is therefore needed to feed a growing population whilst minimizing negative impacts on the environment, biodiversity, and climate. Full accounting of the net global warming potential (GWP) of management practices can provide a holistic approach for identifying cropping systems that promote sustainable agriculture intensification to ensure food security whilst mitigating climate change.

How could we know if agricultural development interventions make contributions to sustainable development goals (SDGs)? Genetically engineered (GE) crops are celebrated as a class of technological interventions that can realize multiple SDGs. But recent studies have revealed the gap between GE crop program goals and the approaches used to assess their impacts. Using four comprehensive reviews of GE crop socio-economic impacts, we identify common shortcomings across three themes: (a) scope, (b) approaches and (c) heterogeneity. We find that the evaluation sciences literature offers alternative assessment approaches that can enable evaluators to better assess impacts, and inform learning and decision-making. We recommend the use of methods that enable evaluations to look beyond the agronomic and productive effects of individual traits to understand wider socio-economic effects.

Salinity is a major problem, impeding soil productivity, agricultural sustainability, and food security, particularly in dry regions. This study integrates quinoa, a facultative halophyte, into a pomegranate-based agroforestry with saline irrigation in northeast Morocco. We aim to explore this agroforestry model's potential in mitigating salinity's effects on quinoa's agronomic and biochemical traits and evaluate the land equivalent ratio (LER). Field experiments in 2020 and 2021 used a randomized block design with three replicates, including monocropping and agroforestry systems, two salinity levels (1.12 and 10.5 dS m−1), four quinoa genotypes (Titicaca, Puno, ICBA-Q4, ICBA-Q5), and a pomegranate control. Salinity significantly decreased total dry matter (40.5%), root dry matter (50.7%), leaf dry matter (39.2%), and root-to-shoot ratio (7.7%). The impact was more severe in monoculture than in agroforestry, reducing dry matter (47.6% vs. 30.7%), grain yield (46.3% vs. 26.1%), water productivity (47.5% vs. 23.9%), and total sugar (19.2% vs. 5.6%). LER averaged 1.86 to 2.21, indicating 86–121% higher productivity in agroforestry. LER averaged 1.85 at 1.12 dS m−1 and 2.18 at 10.5 dS m−1, reaching 2.21 with pomegranate-ICBA-Q5 combination. Quinoa–pomegranate agroforestry emerges as an innovative strategy, leveraging quinoa's salt resistance and agroforestry's potential to mitigate salinity impacts while enhancing land use efficiency.

Agroecology is highly promoted in research and development discourse as a holistic and effective response to climate change. The objective of this study is to contribute to the analysis of the existing evidence that agroecology enables climate change (CC) adaptation and mitigation in the agricultural systems of Latin America, a region known for pioneering the development of this science, praxis, and movement. We applied the PRISMA method to analyze the existing literature providing such evidence. Stakeholder interviews were used to obtain in-depth perceptions of agroecology's contributions to CC adaptation and mitigation from a wide range of actors and development practitioners based in Colombia, Ecuador, and Peru: farmers, NGO representatives, researchers, university program leaders, and public officials. From a total of 1821 initially identified articles, 62 were screened, and 24 case studies analyzed for methods and evidence provided. Twenty-six stakeholders were interviewed. Combining quantitative and qualitative assessment methods, the scientific literature shows that agroecological systems are appreciated for addressing resilience in a systemic way hence not just climate change per se. Mitigation was generally assess by quantitative approaches. Integrating stakeholders' discourse to our analysis highlighted their knowledge of underlying processes contributing to farm CC resilience, where crop and animal diversification and integration of trees into farming systems are central. Stakeholders attributed agroforestry and less use of synthetic fertilizers as important roles for mitigation. Our study highlights the pertinence of combining systematic analyses of the evidence and perceptions drawn from a plurality of stakeholders to recognize the positive contribution of agroecology to climate change adaptation and resilience. However, it also pointed to future research that further assesses the specific trade-offs and synergies between agroecological practices, mitig

Background and aims: Cover crops can efficiently increase nitrogen (N) recycling in agroecosystems. By providing a green-manure effect for the next crop, they allow reduced mineral fertilisation. We developed a decision-support tool, called MERCI, to predict N available from cover crop residues over time, from a single measurement of fresh shoot biomass. Methods: We coupled a large experimental database from France with a simulation experiment using the soil-crop model STICS. More than 25 000 measurements of 74 species of cover crops as a sole crop or bispecific mixtures were collected. Linear regression models, at the species, family or entire-database level depending on the data available, were built to predict dry biomass, N amount and C:N ratio. Dynamics of N mineralized and leaching from cover crop residues were predicted at 24 contrasting sites as a function of the biomass, carbon (C):N ratio and termination date. Results: Correlations between fresh biomass, dry biomass and N amounts in experimental data were strong (r = 0.80-0.96), and predicted N amounts in fresh shoot biomass were relatively accurate. Percentages of N mineralized and leached simulated by STICS were explained mainly by the C:N ratio, site and number of months after termination, but to different degrees. Conclusion: MERCI is an easy and robust decision-support tool for predicting N release in the field, and could thus be adopted by advisors and farmers to improve management of nutrient recycling in temperate arable cropping systems.

Background: In an environment where the adoption of improved varieties resulting from plant breeding programs is limited, it is essential to identify end-user preferences beforehand. A participatory survey was conducted in eight localities in Korhogo and Bouaké regions (central and northern Cote d'Ivoire respectively) to identify producers' preferences and increase the adoption of improved varieties. The study involved 160 producers and consumers through focus group discussions and individual interviews. Results: Sweetpotato is mostly grown on small plots (<1 ha) of land (89.2%), with women (66%) as the main producers. In the Bouaké region, sweetpotatoes are grown on mounds (100%), whereas in Korhogo they are grown on ridges (86.2%). The main food products or forms of preparation from roots are fries (34.7%), boiled (34.3%), mashed (12.4%), and sweetpotato stew (9.1%). Major constraints, including low price of roots (26.3%), low productivity (16.2%), and post-harvest storage issues (14.5%), were identified as affecting sweetpotato production. Conclusions: The selection of new varieties should be oriented towards high-yielding varieties with high dry matter content, deployed stems, and roots of round, oblong, or elliptical shape with good culinary characteristics (dry matter, sweet taste, dry texture, absence of fiber). Plants must be drought resistant, be tolerant to poor soil, diseases, and pests, and have a good yield. The color of skin and flesh of the sweetpotato, although constituting criteria of choice, are not essential for the acceptance or the rejection of a variety by users.

"Why do many farmers still resist adopting and scaling agroforestry? Are the economic benefits not enough, or not perceived to be enough? Or are there other reasons? These are the questions that were asked when work began on Tropical Forest Issues 62. This issue contextualizes agroforestry in four introductory articles in terms of economic viability and resilience, gender inclusiveness, interactions with climate change and biodiversity and barriers to adoption. We then present 26 case studies from Africa, Asia, and Latin America that show the clear and tangible benefits from the adoption of agroforestry. These 26 examples of agroforestry at work, from a range of developing countries, all show that agroforestry provides direct and indirect benefits to farming families and the wider economy. The well-documented case studies show that agroforestry “works” — it contributes to improved livelihoods (including direct cash income), subsistence activities, employment and other community benefits. In highlighting the reasons for its success in a range of contexts, we hope to demonstrate that agroforestry can spread, encouraging other farmers to develop and expand more diversified, productive and resilient farming systems. Depending on the local context and individual traditions and perceptions, different farmers will have a preference for different agroforestry practices. This shows the importance of developing locally owned agroforestry production systems in order to achieve the full range of benefits. The articles in this issue describe a wide range of agroforestry practices from an array of environments and socioeconomic conditions.

Conservation agriculture (CA), combining reduced or no tillage, permanent soil cover, and improved rotations, is often promoted as a climate-smart practice. However, our understanding of the impact of CA and its respective three principles on top- and subsoil organic carbon stocks in the low-input cropping systems of sub-Saharan Africa is rather limited. This study was conducted at two long-term experimental sites established in Zimbabwe in 2013. The soil types were abruptic Lixisols at Domboshava Training Centre (DTC) and xanthic Ferralsol at the University of Zimbabwe farm (UZF). The following six treatments, which were replicated four times, were investigated: conventional tillage (CT), conventional tillage with rotation (CTR), no tillage (NT), no tillage with mulch (NTM), no tillage with rotation (NTR), and no tillage with mulch and rotation (NTMR). Maize (Zea mays L.) was the main crop, and treatments with rotation included cowpea (Vigna unguiculata L. Walp.). The soil organic carbon (SOC) concentration and soil bulk density were determined for samples taken from depths of 0–5, 5–10, 10–15, 15–20, 20–30, 30–40, 40–50, 50–75 and 75–100 cm. Cumulative organic inputs to the soil were also estimated for all treatments. SOC stocks at equivalent soil mass were significantly (p<0.05) higher in the NTM, NTR and NTMR treatments compared with the NT and CT treatments in the top 5 cm and top 10 cm layers at UZF, while SOC stocks were only significantly higher in the NTM and NTMR treatments compared with the NT and CT treatments in the top 5 cm at DTC. NT alone had a slightly negative impact on the top SOC stocks. Cumulative SOC stocks were not significantly different between treatments when considering the whole 100 cm soil profile. Our results show the overarching role of crop residue mulching in CA cropping systems with respect to enhancing SOC stocks but also that this effect is limited to the topsoil. The highest cumulative organic carbon inputs to the soil were obser

Crop breeding in sub-Saharan Africa has made considerable gains; however, postharvest and food-related preferences have been overlooked, in addition to how these preferences vary by gender, social difference and context. This context is changing as participatory approaches using intersectional gender and place-based methods are beginning to inform how breeding programmes make decisions. This article presents an innovative methodology to inclusively and democratically prioritise food quality traits of root, tuber and banana crops based on engagement with food systems actors and transdisciplinary collaboration. The outcome of the methodology is the Gendered Food Product Profile (GFPP) – a list of prioritised food quality characteristics – to support breeders to make more socially inclusive decisions on the methods for trait characterisation to select genotypes closer to the needs of food system actors. This article reviews application of the methodology in 14 GFPPs, presents illustrative case studies and lessons learned. Key lessons are that the transdisciplinary structure and the key role of social scientists helped avoid reductionism, supported co-learning, and the creation of GFPPs that represented the diverse interests of food system actors, particularly women, in situ. The method partially addressed power dynamics in multidisciplinary decision making; however, effectiveness was dependent on equitable team relations and supportive institutions committed to valuing plural forms of knowledge. Actions to address power asymmetries that privilege particular types of knowledge and voices in decision making are crucial in techno-science projects, along with opportunities for co-learning and long-term collaboration and a transdisciplinary structure at higher level.

Agroforestry is a promising way to sustain land use efficiency in semi-arid areas. In this study, we introduce quinoa as a drought- and salinity-tolerant crop in olive-based agroforestry. We investigated how the microclimate created by olive trees affects agronomic and biochemical traits in quinoa and evaluated the performance of this new olive-based agroforestry system in terms of land equivalent ratio (LER). Field experiments were carried out under two pedoclimatic conditions (S1) and (S2) using a randomized complete block design with two cropping systems (sole crop (SCS) and agroforestry (AFS) systems), four quinoa cultivars (Puno, Titicaca, ICBA-Q5, and ICBA-Q4) and one olive orchard as a control (OR) in each block. Our results show that AFS had lower grain yield (−45%), dry biomass (−49%), and crop water productivity (−44%), but higher plant height (12%), grain protein (4%), saponin (26%), total polyphenol (12%), and DPPH (9%) contents compared to SCS. The highest grain yield was recorded for Titicaca and ICBA-Q5 (1.6 t ha−1). The LER ranged from 1.57 to 2.07, indicating that the overall productivity was 57% to 107% higher in the agroforestry system compared with the monoculture. We suggest that quinoa–olive tree intercropping could be a promising agroecological practice under semi-arid conditions.

This study aimed to examine the correlations between the agroecological status of farms and their viability in agro-sylvo-pastoral systems located in the savannah areas of West Africa. The methodology is based on farm surveys (to assess agroecological farm status) and on farmers' focus group discussions (to assess viability at the farm level). Agroecological farm status was established by considering 15 agricultural practices: 4 on by-products recycling; 4 on soil protection; 4 on industrial inputs limitation; 2 on smart use of natural resources; 1 on cropping diversification; An agroecological (Ae) scoring system was used to establish an Ae ranking by farm type. Farm level viability was established by men and women farmers' focus group discussions: Inventory of viability enhancing and viability-weakening factors; Rating intensity of each viability factor. A scoring system was used to establish Viability ranking by farm type. Four iconic farm types were considered: Small crop-oriented (T1); Medium-size crop-oriented (T2); Large crop-livestock oriented (T3); Livestock-oriented (T4). The findings demonstrate that the viability of agro-sylvo-pastoral systems is not solely dependent on their agroecological status. The ranking of the four farm types, from the first to the last position, is T4, T2, T3, and T1 for agroecology; and T2, T3, T4 and T1 for viability. Our study reveals that T1 farms in Koumbia are not highly agroecological or highly viable. Similarly, farms with the largest cultivated areas (T3) and herds (T4) are not the most agroecological or viable. The best balance between agroecology and viability is struck by T2 farms. We recommend promoting the development of T2 farms that demonstrate the best congruence between agroecology and viability as a model for T1, T3, and T4 farmers. Depending on the agroecological status, one farm could be more or less viable.

La faible productivité de l'agriculture en Afrique subsaharienne est due en grande partie à la dégradation de la fertilité des sols. Les agricultures familiales, pilier de la sécurité alimentaire de cette grande région, doivent relever le défi de la restauration et du maintien de la capacité productive des terres. Les pratiques endogènes des producteurs telles que les associations céréales-légumineuses, les jachères pâturées, les parcs arborés... ne permettent plus d'entretenir la fertilité sur des surfaces cultivées qui s'agrandissent, surtout lorsque les sols sont carencés. Durant quatre décennies, les décideurs et acteurs du secteur agricole ont privilégié la vulgarisation des engrais de synthèse. Mais l'utilisation des engrais minéraux demeure faible et bien en deçà de la moyenne de la consommation mondiale (15 kg/ha contre 135 kg/ha). Après avoir longuement promu l'utilisation de fumure organique, la recherche invite désormais à diversifier les sources de biomasse fertilisante via l'agroforesterie, les associations avec les légumineuses, l'agriculture de conservation. D'autres techniques de conservation de l'eau et du sol ont également été mises en avant. C'est bien la combinaison de différentes pratiques qui est à construire avec les agriculteurs pour chaque situation de production, en fonction des ressources disponibles localement, d'un apport raisonné d'engrais de synthèse et d'amendement, des savoirs paysans et scientifiques. Pour cela, il est nécessaire (i) de modifier les postures des chercheurs et des décideurs vis-à-vis des ruraux et (ii) de réviser les politiques publiques toujours focalisées sur l'usage des engrais minéraux, afin de fournir des services d'appui-conseil plus diversifiés, performants et intégrant les besoins de transitions agroécologiques indispensables aujourd'hui dans un contexte de changement climatique.

Coffee beans are a major agricultural product and coffee is one of the most widely traded commodities and consumed beverages globally. Supply chains and cropping systems are very diverse, with contrasted potentials and performance, as well as environmental impacts. Life Cycle Assessment (LCA) studies are needed to inform on reduction in impacts, but there is a lack of comprehensive understanding of the variability of existing LCA results and impacts of the cropping systems and their trade-offs along the supply chains. In an attempt to address this knowledge gap, the paper presents a systematic literature review of coffee LCA, considering a total of 34 studies covering 234 coffee systems. Global warming potential (GWP) was the impact category most reported in the literature, but the results varied greatly at both the farm and drink levels. For the former, the GWP values ranged from 0.15 to 14.5 (median: 3.6) kg CO2 eq./kg green coffee beans and for the latter the values ranged from 2 to 23 (median: 8.8) kg CO2 eq./kg consumed coffee in drinks. Main contributors to the GWP of production of green coffee beans were land use change (LUC), fertilisers and wet processing. However, there were great inconsistencies across studies in terms of LUC accounting, field emissions and wet process modelling. Green coffee beans production was also the main contributor to the GWP of coffee consumed, followed by brewing and coffee cup washing. Some studies covered other impacts, in addition to GWP. At both the farm and drink levels, fertilisers and pesticides were the main contributors to eutrophication and acidification, and to ecotoxicity, respectively. Brewing was the second main contributor at the drink level, in some cases the top contributor for energy-related indicators. Assumptions on packaging, cup washing and waste disposal were highly variable across studies. Water impact indicators were hardly comparable due to the system variability and method inconsistencies. Given the lar

Ce fascicule, publié à l'occasion du Salon international de l'agriculture de Paris 2024, présente l'évolution des recherches sur la gestion de la fertilité des sols en Afrique subsaharienne, à partir d'un choix d'articles publiés au fil des ans par la revue Cahiers Agricultures.

CONTEXT: Over the past two decades, the Mekong region has experienced significant transformation of its agricultural sector from subsistence farming to export crops driven by the expansion of agricultural land and of irrigation, plus intensification thanks to mechanization and the use of chemical inputs. In the context of agrarian transition, maintaining “organic by default” rice farming systems that do not rely on chemical inputs, is challenging. OBJECTIVE: Based on a case study in Preah Vihear, the organic province of Cambodia, this paper examines whether organic rice certification can maintain “organic by default” practices in a context of unprecedented agricultural intensification. METHODS: Using agrarian diagnosis, we investigated the impacts of an organic rice certification scheme on the future of organic rice-based farming systems. We built a functional typology of five farming systems that co-exist in the study area to understand the roles of organic rice in each system. RESULTS AND CONCLUSIONS: From an economic perspective, organic rice is less profitable than recently introduced cash crops, e.g. cassava, cashews. The positive impact of certification of organic rice is threatened by lock-in factors, e.g. labor diversification in both farming and non-farming activities, cash flow management, the certification process, leading farmers to abandon organic rice for cash crops for export. We discuss the key role of agricultural cooperatives in the certification process of organic rice. SIGNIFICANCE: The paper questions the capacity of a certification scheme to keep up with the process of intensification that undermines the profitability of the remaining “organic by default” rice systems. Beyond the significance of the results in the study area, one of the last strongholds of traditional rice systems in Cambodia, the paper illustrates the disappearance of “organic by default” rice systems in the whole country as well as in the Mekong region.

To prepare the roadmap for its ten-year research on the cotton sector, CIRAD worked with a number of stakeholders to identify the main challenges facing the sector in the coming years, both globally and in Africa in particular. This document presents the 35 challenges identified, grouped into 7 macro-challenges. Several of these challenges are global in scope, and international collaboration is needed to address them.

Farms in the savannah areas of Sub-Saharan Africa are largely based on agro-pas-toral systems. They produce large quantities of crop co-products (CCP, i.e. straw, tops, stalks) and livestock co-products (LCP, i.e. faeces). However, only a small proportion of co-products are recovered to meet their needs for fodder, manure and mulch. Improving the recovery of co-products is an effective way to boost farm autonomy, productivity and long-term resilience. It also helps farmers adapt their practices as part of their agroecological transition. The CoProdScope (CPS) tool has been designed with a view to: 1) carrying out an annual review of CCP and LCP management at farm level in order to assess the proportion of unrecovered co-products, and to identify recovery potential (Review step); 2) co-designing a strategy with the farmer (Management Advisory step), with the aim of recovering CCP and LCP as fodder (storage and field grazing), manure (pit and pen manure), mulch (straws and stalks covering the soil ) and for distribution to third parties. This paper describes how the CPS tool works, presents the review and management advisory stages, and outlines the potential digital development that would make the CPS suitable for field use by agricultural advisors.

In Western Africa, agro-sylvo-pastoral systems are dominant and food demand is booming. To meet this demand, many farmers intensify the production with industrial inputs (mineral fertilizers, feeds, pesticides, herbicides). However, the price of these inputs is rocketing. To face this issue, some farmers reconsider crops, livestock, and tree synergies and by-product recycling to increase their production sustainably at a lower cost. The study aimed to characterize the diversity of Koumbia's farming systems and to assess farming systems' technical performance in an agroecological perspective. We surveyed 391 farms in the county of Koumbia (Burkina Faso). Considering 15 agricultural practices (4 on by-products recycling, 4 on soil protection, 4 on industrial inputs limitation, 2 on smart use of natural resources, and 1 on cropping diversification), a multivariate analysis (PCA+HAC) combined to an agroecology (Ae) scoring system (−15 to +15) based on 15 specific indicators (one/practice), we highlighted 3 agroecological farming systems clusters. These clusters are distributed along a gradient of agroecology intensity (Ae+: high degree of Ae, Ae+/−: medium degree, and Ae−: poor degree). Ae+ farms (Ae score: +3.0) group 17% of the farms, Ae+/− (Ae score: −4.5) group 58% of the farms, and Ae− (Ae score: −10.5) group 25% of the farms. Ae+ raise more livestock and recycle a higher rate of crop-livestock by-products in fodder, organic manure, and mulch. These recycling practices are facilitated by better levels of equipment for transportation and storage and soil water and crop residue conservation measures, including maintenance of the wooded park on the cultivated fields. This set of practices, which close better the agricultural system, produces a systemic effect which has a positive impact on yields and on the whole ecosystem. Our findings outline for the first time that crop-livestock synergies and by-product recycling are major factors of agroecological transition in a

Agriculture in semi-arid Burkina Faso is dominated by mixed crop-livestock smallholder farms with limited investment capacity in production factors, such as improved seeds, fertilizer and equipment. Hence, to make a living, farmers try to make the best use of available resources based on principles of agro-ecology, including crop diversity and nutrient and biomass recycling. We investigated farm-level management of resources (soil, crops and livestock) through time to assess whether the current management options were able to sustain crop and livestock production and fulfil household food requirements. We ran a one-year detailed farm monitoring campaign in collaboration with 22 volunteer farmers representing the diversity of the farming system in our study area. We quantified inputs and outputs in the cropping system (177 fields) for one rainy season. In addition, the weekly dynamics of crop residues left on field were quantified. Moreover, inflow and outflow of resources at farm level were quantified weekly. The cropping system was characterized by a negative nitrogen balance of about 12 kg N/ha/year, with market-oriented farms and large livestock owners having the most negative balance. Legumes grown (sole and intercropping) contributed to alleviate the nitrogen depletion by adding 15 kg N/ha/year to the nitrogen inputs through atmospheric fixation. However, cereal-legume intercropping did not significantly reduce the nitrogen deficit in comparison to sole cereal cropping mainly because of the small proportion of legumes (8%) in intercropped fields. Livestock grazed crop residues left on the soil (739 kg dry matter/ha on average) at a rate of 26 − 76 kg/ha/week, thus strongly reducing the potential for mulching in the region. Livestock protein requirements were rarely met from farm-produced feed with average feed gaps ranging between 40% and 89% of the daily requirements for small and large herd keepers respectively. Large livestock (cattle) owners relied on trans

To study the impact of pesticide uses in agriculture on human health, data on the types and quantities of pesticide active substances introduced into the environment over a long period of time are needed. However, when there is no systematic or available written records of pesticide applications, the characterization of environmental contamination remains challenging. In this technical note, we propose a method to organize heterogeneous information to represent the spatial dynamics of pesticide uses, with the case of Guadeloupe, French West Indies. Based on various data sources (paper maps, digital geographic data, articles and technical reports, pesticide products information, interviews), different databases were built: i) a land use database (1969-2019), with maps of the main three groups of crops in Guadeloupe: banana, sugar cane and market gardening; ii) a database of agricultural practices regarding the use of pesticides and their evolution over time for these groups of crops; iii) a database of available active substances according to time. Homogenized datasets of banana, sugar cane and market gardening plots allow to visualize the crop distribution at different periods of time and the evolution trend of cultivated areas. The database on agricultural practices regarding the use of pesticide includes the description of different 'pesticide itineraries' - characterized by information on the cropping system and on the schedule of pesticide applications, and their evolution through time. The database on active substances includes two types of information: for each year since 1960, the characteristics of authorized active substances based on regulation, and of available active substances, based on farmers' practices in Guadeloupe. All databases are made available on an open data repository; they will be used to derive indicators of pesticide pressure and study the link between cancer cases and the presence of pesticides in the environment.

En Haïti, les systèmes agricoles sont fortement vulnérables au changement climatique. Cette étude vise à analyser la pertinence d'une démarche de co-conception de stratégies d'adaptation des exploitations agricoles au changement climatique dans une zone hautement vulnérable telle que Haïti. Menée à Saint Michel de l'Attalaye, l'étude reposait : (i) sur la réalisation d'un diagnostic des performances technico-économiques de 24 exploitations représentatives des trois principaux types de stratégies d'adaptation observées, et (ii) sur la co-conception de stratégies innovantes avec un échantillon plus réduit de 9 agriculteurs. Les résultats de l'étude montrent que les performances initiales des 24 exploitations en termes de couverture des besoins caloriques du ménage, revenus, et émissions de gaz à effet de serre sont différentes pour les trois types de stratégies. La diversification des systèmes de production agricole joue un rôle crucial dans les performances mesurées. Les stratégies proposées par les 9 producteurs visent à accroître cette diversification tout en renforçant la place de la canne à sucre dans les systèmes de production, mais les changements pensés sont incrémentaux. D'autres boucles de co-conception pourraient être envisagées pour explorer avec les producteurs des changements de rupture articulant augmentation des capacités de production des exploitations et adaptation au changement climatique. Cette étude pilote en Haïti pourrait être répliquée dans d'autres zones hautement vulnérables afin de co-concevoir des systèmes innovants tenant compte des contraintes spécifiques auxquelles sont exposés les agriculteurs.

CONTEXT: In Guadeloupe, the use of a persistent pesticide (chlordecone) contaminated one third of the island's agricultural soils, causing a major environmental crisis. In the aftermath, banana farmers significantly changed their management practices to decrease their pesticide use. With the support of research, farmers have tested and adopted various agroecological practices, such as planting cover crops and using vitroplants and fallow. However, the use of animals to decrease pesticide use on banana plantations has not yet been explored. OBJECTIVE: This study aimed to co-design agroecological cropping systems that integrate animals as an alternative means to manage weeds. METHODS: The study was based on co-design workshops involving farmers, advisors and scientists, a survey of local practices of integrating animals within cropping systems, on-farm experiments with four farmers during which a total of 20 four-month-old male lambs were introduced within their cropping systems, and reflexive monitoring two and six months after the end of the experiments. RESULTS AND CONCLUSIONS: The introduction of sheep into cropping systems was the option deemed the most promising after three co-design workshops. Animals already were integrated into some banana-based farming systems in the study area, but this integration mainly consisted of cattle grazing on fallow land. The on-farm experiments highlighted that sheep made it possible to reduce the herbaceous cover on banana plantations by almost 60%. The growth performance of the lambs allowed by the herbaceous cover was within the range observed for this breed when reared on pastures (50–139 g/day). In this experiment, the lambs were not reared for meat, since the animals were, unsurprisingly, contaminated by chlordecone. The farmers appreciated that the practice enabled them to eliminate a labor-intensive activity (removing by hand the vines around the banana pseudo-stem) and radically reduce brush cutting. Piloted by a technic

Diversification of cropping systems is a lever for the management of epidemics. However, most research to date has focused on cultivar mixtures, especially for cereals, even though crop mixtures can also improve disease management. To investigate the benefits of crop mixtures, we studied the effect of different crop mixture characteristics (i.e., companion proportion, sowing date, and traits) on the protective effect of the mixture. We developed a SEIR (Susceptible, Exposed, Infectious, Removed) model of two damaging wheat diseases (Zymoseptoria tritici and Puccinia triticina), which were applied to different canopy components, ascribable to wheat and a theoretical companion crop. We used the model to study the sensitivity of disease intensity to the following parameters: wheat-versus-companion proportion, companion sowing date and growth, and architectural traits. For both pathogens, the companion proportion had the strongest effect, with 25% of companion reducing disease severity by 50%. However, changing companion growth and architectural traits also significantly improved the protective effect. The effect of companion characteristics was consistent across different weather conditions. After decomposing the dilution and barrier effects, the model suggested that the barrier effect is maximized for an intermediate proportion of companion crop. Our study thus supports crop mixtures as a promising strategy to improve disease management. Future studies should identify real species and determine the combination of host and companion traits to maximize the protective effect of the mixture.

Natural rubber is considered a strategic material for the development of Sri Lanka by the Ministry for Plantations. In response to climate change, the country has adopted a policy focusing on resilience and sustainable development. It is in this context that Ksapa initiated the RIVER project in 2022, aiming to develop a program to strengthen agricultural capacity in Sri Lanka. To carry out this project, the company commissioned YAPI Expertise to provide agroforestry intercropping models based on rubber trees with good agronomic performance and economically of interest to producers to diversify their sources of income. The RIVER project is implemented in two districts in south-eastern Sri Lanka: Moneragala and Ampara. This study began with an analysis of the literature in order to select crops that could be intercropped with rubber. In parallel, 80 interviews, prepared by YAPI Expertise, were conducted in the field by a local organisation, LOAM. The aim of these interviews was to identify rubber intercrop models already implemented in the study areas and to understand the reasons why farmers adopted these models. The interviews were analysed statistically by MCA and Chi². By combining these with the literature review, the study established 5 models (Pineapple model, Cocoa model, Banana model, Passion fruit model, Soursop model) for several intercrops that could be planted with rubber, with potential for adoption by local farmers. Finally, selection criteria were established for each model. Both their strong and weak points are presented, since an effective model cannot rely on agronomic analysis alone and it will be essential to adapt the choice of crops to the local market and to farmers' needs.

Fire is a natural element of some tropical dry ecosystems. However, during the last decades, fire occurrence has become more frequent and intense due, in part, to climate change and land use transformation. This is the case in the Gran Chaco Americano, one of the largest dry forests all over the world that extends across Argentina, Paraguay, Bolivia and Brazil. Fire has shaped the Gran Chaco landscape since ancient times, but today, as in many other regions, the pattern, frequency, severity and intensity are being dramatically altered. Based on information collected mainly over the last two decades, this paper presents a detailed review of the available literature on the fire regime across the Gran Chaco region. Here, we present a multi-disciplinary understanding considering fire behavior and dynamics in the study ecosystem within a very specific ecological, administrative and historical framework. A noteworthy aspect of this review indicates the clear imbalance between regions in terms of available literature; while information about the Argentine Chaco is abundant, the literature for the Paraguayan or Bolivian Chaco is practically non-existent. The rainfall gradient and drought periods are key climatic drivers of fire ignitions while cattle ranching is the main socioeconomic activity of this region and key precursor of forest fires. In general, a substantial part of the available information focused on ecological aspects of the fire regime as the effect of fires on plant functional traits such as bark thickness, resprouting ability and flammability patterns. Other post fire effects on soil, invasive species, herbivory and soil seed banks have been also explored in detail to understand ecosystem recovery and research needs. We finally highlight current necessities and future prospects, mainly related to soil burn severity (SBS), invasive species and wildlife impact. Although our study specifically focused on changes in the fire regime of the Gran Chaco, some genera

The growing demand for sustainable agriculture is raising interest in intercropping for its multiple potential benefits to avoid or limit the use of chemical inputs or increase the production per surface unit. Predicting the existence and magnitude of those benefits remains a challenge given the numerous interactions between interspecific plant-plant relationships, their environment, and the agricultural practices. Soil-crop models are critical in understanding these interactions in dynamics during the whole growing season, but few models are capable of accurately simulating intercropping systems. In this study, we propose a set of simple and generic formalisms (i.e. the structure and mathematical representation necessary for designing a model) for simulating key interactions in bi-specific intercropping systems that can be readily included into existing dynamic crop models. This requires simulating important processes such as development, light interception, plant growth, N and water balance, and yield formation in response to management practices, soil conditions, and climate. These formalisms were integrated into the STICS soil-crop model and evaluated using observed data of intercropping systems of cereal and legumes mixtures, including Faba bean-Wheat, Pea-Barley, Soybean-Sunflower, and Wheat-Pea mixtures. We demonstrate that the proposed formalisms provide a comprehensive simulation of soil-plant interactions in various types of bispecific intercrops. The model was found consistent and generic under a range of spring and winter intercrops (nRMSE = 25% for maximum leaf area index, 23% for shoot biomass at harvest, and 18% for grain yield). This is the first time a complete set of formalisms has been developed and published for simulating bi-specific intercropping systems and integrated into a soil-crop model. With its emphasis on being generic, sufficiently accurate, simple, and easy to parameterize, STICS is well-suited to help researchers designing in silico

CONTEXT: Integration of farms into markets with adoption of maize as a cash crop can significantly increase income of farms of the developing world. However, in some cases, the income generated may still be very low and maize production may also have strong negative environmental and social impacts. OBJECTIVE: Maize production in northern Laos is taken as a case to study how far can farms' performance be improved with improved crop management of maize with the following changes at field level: good timing and optimal soil preparation and sowing, allowing optimal crop establishment and low weed infestation. METHODS: We compared different farm types' performance on locally relevant criteria and indicators embodying the three pillars of sustainability (environmental, economic and social). An integrated assessment approach was combined with direct measurement of indicators in farmers' fields to assess eleven criteria of local farm sustainability. A bio-economic farm model was used for scenario assessment in which changes in crop management and the economic environment of farms were compared to present situation. The farm model was based on mathematical programming maximizing income under constraints related to i) household composition, initial cash and rice stocks and land type, and ii) seasonal balances of cash, labour and food. The crop management scenarios were built based on a diagnosis of the causes of variations in the agronomic and environmental performances of cropping systems, carried out in farmers' fields. RESULTS AND CONCLUSIONS: Our study showed that moderate changes in crop management on maize would improve substantially farm performance on 4 to 6 criteria out of the 11 assessed, depending on farm types. The improved crop management of maize had a high economic attractiveness for every farm type simulated (low, medium and high resource endowed farms) even at simulated production costs more than doubling current costs of farmers' practices. However, while a

Societal Impact Statement : Yam is a major tropical root crop and a staple food for millions of people in West Africa. The model used in this study shows that promoting the use of improved seed tubers would help increase yields and profitability for farmers. This could lead to improved food security, increased income and higher standards of living. Additionally, the model serves as a useful decision-support tool for farmers and technicians to choose, depending on the species, the optimum seed-tuber weight and planting date. This study provides agronomic arguments to justify investments in the improvement of yam planting materials in West Africa. Summary: Yam (Dioscorea spp.) is a major tropical root crop, grown mainly in West Africa using traditional extensive techniques. Farmers typically reuse seed tubers by setting aside up to 30% of their production for the next season, leading to high planting material variability that affects yields. Several initiatives aim to promote the use of improved seed tubers. However, to help their adoption, it is necessary to quantify the agronomic and economic advantages. To address this, a model for individual plant growth and development was developed based on six experiments in Benin from 2007 to 2009. This model simulates the combined effect of emergence (through photoperiod and temperature) and seed-tuber weight on yam plant growth and development. Its predictions were highly correlated with observed plant tuber yield (R2 > 0.83). Results highlight the crucial role of key processes such as seed-tuber physiological age and photoperiod sensitivity. The study shows that for the traditional planting dates, the use of improved planting material could lead to a yield increase of 22%–27% and a gain in profitability of 30% and 40% for Dioscorea alata and Dioscorea rotundata, respectively. The model proved to be a useful decision-support tool for choosing an optimum seed-tuber weight, depending on the species and the planting date. This

Cereal-legume intercropping has been traditionally practiced across West Africa by farmers and provides resilience of agriculture to climate variability. Intensification of these extensive intercropping systems in order to meet future food demand is critical. This study aims at evaluating the agronomic performance of the intensification of millet-cowpea intercropping with low cowpea density, and its variation with climate variability, using an on-station experiment in Bambey, Senegal. Two trials (irrigated vs rainfed) were set up to compare millet sole- and inter-cropping with a grain and a fodder variety of cowpea, in 2018 and 2019. Two levels of fertilization were tested: 0 kg(N) ha−1 and 69 kg(N) ha−1. The two cropping years were contrasting and water stress around flowering and/or during grain filling (indicated by the Fraction of Transpirable Soil Water) was higher in 2019 than in 2018 in the rainfed experiment. In both experiment and for all treatments, land equivalent ratio (LER) in the intercropping was 1.6 and 1.4 for grain and biomass respectively. Millet aboveground biomass was significantly higher in intercropping than in sole cropping in the irrigated experiment but not in the rainfed experiment. In the rainfed experiment, the interaction between cropping system and year was significant, so that millet aboveground biomass was greater in intercropping than in sole cropping in 2018 (year of lower water stress) but not in 2019 (year of higher water stress). The effect of fertilization on millet aboveground biomass did not significantly interact with cropping system (sole vs intercrop). For grain yield, fertilization interacted significantly with the cropping system in the irrigated trial: the benefits of intercropping on millet grain yield were greater with 69 kg(N) ha−1 than with 0 kg(N) ha−1. This significant interaction could not be observed in the rainfed trial, potentially due to water stress. These results show that the level of water stress (related

Non-active agricultural land (NAAL) mapping in West Africa is essential to accurately assess agricultural systems and its contribution to food security and agro-ecological sustainability of current practices, and yet the available mapping methodologies are not adapted to the environmental and cropping conditions encountered when addressing tropical smallholder agriculture. In this study we present a strategy that makes use of Sentinel-2 image time series, CHIRPS monthly rainfall data and multiple years of in-situ data obtained from the JECAM database to map NAAL in a Soudanian site in Burkina Faso (Koumbia) between the years 2016 and 2021. In a first step we generated annual land use maps in four broad classes (managed, unmanaged, evergreen and non-vegetated) to detect fields being actively cultivated in a given year, and in a second step, we used these annual land use maps to differentiate non-active agricultural land by identifying shifts from one year to another. For the validation part, we analyzed the sensitivity of classification accuracy to in-situ data pre-processing by building 5 experimental validation data sets. The unmanaged classes F1-scores of the land use maps ranged between 0.86 and 0.98, depending on the year, whereas NAAL classes F1-scores ranged from 0.75 to 0.92 when validated against the most restrictive data set (pixels with no missing reference data for the period considered). NAAL represents between 7% to 14% of the study site cropland depending on the year. The higher class probabilities are in areas where data was available, whereas the low probabilities are localized and linked to transition areas on the outskirts of the department. Our results indicate that a multi-annual approach can allow NAAL mapping under challenging environments, yet efforts are to be made to develop more cost-efficient unsupervised solutions.

This book analyses situations of coexistence and confrontation of agricultural and food models according to four major dimensions of territorial development: the tension between specialisation and diversification; innovation; adaptation; and food transition. New agricultural and food models are being deployed in territories around the world in response to criticisms of the old forms of agriculture and food production, and in order to meet new challenges. These models embody archetypes of the observed diversity, actors' projects or new norms. A number of conceptual studies and case studies from France and other countries allow us to understand the interactions between these models (confrontation, complementarity, co-evolution, hybridisation, etc.), taking us well beyond the characterisation of their diversity and the evaluation of their relative performances. The coexistence and confrontation of these models build up their capacity for radical change. The book asks original questions about the analytical framework, its methodological challenges and the expected outcomes for the support of agricultural and food development in rural and urban territories. It is intended for researchers, teachers, students and professionals interested in territorial development.

Duru et al. (Agron Sustain Dev 35:1259-1281, 2015) highlighted a missing tool for studying and improving the performance of cropping systems in the transition to highly diversified agriculture. In response, this paper proposes a concept for designing, modeling, monitoring, and auditing desired ecosystem services, in intercropping and agroforestry systems. We have labelled this concept ESSU (Ecosystem Services functional Spatial Unit). It delimits the smallest spatial unit encompassing all the interacting species and other functional components (e.g., crops, trees, livestock, spontaneous vegetation, semi-natural habitats such as hedges, ditches, forest patches, and animals) that together provide a specified set of ecosystem services. The novel ESSU concept allows representation of an entire diversified agroecosystem by the repetition of the spatial unit that provides the same sets of targeted ecosystem services as the agroecosystem it represents. It can then be used for various activities, such as the (i) design of more efficient agroecological systems according to the targeted ecosystem services; (ii) rapid audit of farming practices for biodiversity/resilience across large tracts of farmland as part of achieving Sustainable Development Goal 2 targets of sustainable food systems; and (iii) modeling such diversified agroecosystems using a motif adapted to represent the targeted ecosystem services and the species spacing design. We demonstrate that the ESSU concept is highly flexible and applicable to a wide range of diversified agroecosystems, like arable intercropping, crop-tree intercropping, tree-tree agroforestry, and agro-pastoralism. We also show its relevance and suitability for representing temporal changes over 1 year, across several years, and over decades, indicating its generalizability and flexibility. We argue that ESSU could open new theoretical and practical research avenues for the study of diversified agroecosystems. Considered with all the knowledg

Agroecological studies on sugarcane intercropping commonly generate complex datasets. A generic database (AEGIS – Agro-Ecological Global Information System) has been developed to facilitate the use of these datasets. The data described in this paper includes data from 8 experiments carried out on Reunion Island from 2012 to 2021 under three soil and climatic conditions to assess the capacity of cover crops in the sugarcane inter-row to control weed growth. Each experiment consisted of the comparison of three treatments in the inter-row: i) sugarcane with chemical weeding, ii) sugarcane with a cover crop sowed in the inter-row, and iii) sugarcane with spontaneous weed flora in the inter-row. The datasets contain data for sugarcane and cover crop observations (e.g., yield), weed flora, including 104 weed species (e.g., ground cover), crop management (including manual and chemical weedings), soil analyses, and daily weather. This dataset provides an adequate experimental dataset to calibrate or validate crop model simulations under intercropping.

Description of the subject. Weed pressure is a main biotic constraint in tropical agriculture. Cover crop mixtures have increased in popularity to limit weed growth through competition for resources, but the relationship between cover crop diversity and weed suppression is still under debate. Objectives. This study aimed to assess the impact of increasing cover crop diversity (one to four species) on weed control during two growing seasons (tropical summer and winter) in Reunion Island. Method. Weed control was expressed regarding ground cover by weeds and weed aboveground dry mass in the mixtures during four months of growth and its response to cover crop traits was tested using structural equation models. Results. While cover crops reduced weed ground cover and dry mass by 60% and 68% on average in summer and winter, respectively, a higher number of cover crop species within a mixture did not increase mean weed control. Nonetheless, weed control was influenced by the mixture composition and improved when including Guizotia abyssinica. Additionally, cover crop traits explaining weed control differed between growing seasons. In summer, weed control was mainly explained by the final cover crop aboveground biomass and leaf area (depletion strategy). In contrast, weed control was mainly explained by the cover crop rate of increase in ground cover (obstruction strategy) in winter. Conclusions. Using traits to characterize cover crop mixture enables us to identify mixtures of species and traits adapted to different growing conditions. Our study suggests that particular attention on species identity rather than diversity should be paid in mixture to improve weed control in tropical conditions.