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Unpacking global agroforestry diversity and configurations: A data-driven analysis for natural climate solutions
Get PDFBackground: Agroforestry is a high-profile natural climate solution (NCS), given its potential to store carbon while also potentially boosting biodiversity and human livelihoods. However, deploying agroforestry as an NCS and increasing agroforestry adoption requires knowing what agroforestry configurations are possible where. Aims and Objectives: As part of an effort to understand global variability in agroforestry's potential as an NCS and to help identify opportunities for scaling, we aimed at providing a globally comprehensive, data-driven, and detailed understanding of what types and configurations of agroforestry practices occur in different parts of the world as well as what products (i.e., specific food crops, fiber, and other tree-based products) are generated. Methodology: We systematically reviewed 25,094 carbon-focused studies to find 1091 papers that provided details about specific agroforestry configurations such as the density and diversity of tree species used and their products. The resulting database is almost 8 times larger than similar previous efforts, spanning 7569 unique agroforestry plots and 83 countries. Key Findings: When we compare our plot distribution against a previously published map of global agroforestry extent, we find that our plots generally span the global distribution of agroforestry (Fig. 1). However, some countries, such as the United States and Australia, are relatively over-represented with a high number of plots in our dataset but a low density of agroforestry systems, whereas others are under-represented with few plots in our dataset but a higher density of agroforestry. We find that these systems collectively contain 1180 tree-like species, which represent more than a tenth of the tree species with a documented human use. While 57% of the plots in our dataset had only one species present, a small fraction (2%) of plots had very high richness (i.e., > 25 species). We also find that the majority of species across all plots in our database are native to the country in which they were planted (59%), but 41% are non-native. These agroforestry species were associated with 379 different crops, and while a few grains showed up predominantly there were many more crops that showed up infrequently (i.e., 71 crops only show up once and 55 show up twice). Main Conclusions: This global map and database of agroforestry diversity and characteristics can help scientists refine the potential of agroforestry as a NCS but also for food security and biodiversity conservation, as well as inform practitioners and policymakers to identify opportunities for scaling agroforestry
Floristic characterisation of forest patches in the vicinity of cocoa plots in the Dominican Republic
Get PDFLittle is known about the structure and composition of forest patches as a base for understanding the ecology and ecosystems services provided to neighbouring crops, so agronomic management and the landscapes surrounding the plantations may affect the abundance and effectiveness of cacao pollinators and thus the value and quality of those crops. This study sought to identify and characterise forest patches situated near cocoa fields in order to construct a gradient in the landscape of two cocoa localities Medina: (San Cristóbal province), and Los Bracitos adjacent to the Loma Quita Espuela Reserve (Duarte province). Three forest patches per locality were located, geo-referenced and characterised and within patch four 10 m2 plots were identified for floristic surveys and trunk measurements of tree and shrub species with a minimum thickness of 5 cm. The species found were identified both in the field and at the herbarium. Species were categorised according to their family, scientific and common names, mean relative presence, biological type, and their biogeographic and conservation statuses. In order to compare floristic biodiversity among the six forest patches, biodiversity indicators of species dominance (Simpson's index), species heterogeneity (Shannon), richness (Chao 1), and similarity (Jaccard) were calculated. In San Cristóbal province comprising both riparian and secondary forests, 49 families were found in the 12 plots sampled, represented by 105 species, mostly arboreal (38.1%) shrub (27.6%), herbs (15.2%), and climbing plants/vines (10.5%); trunk diameters at breast height of 5 - 70 cm and heights from 1 - 25 m. The most abundant families are Myrtaceae, Bromeliaceae, Fabaceae, Mimosaceae and Sapindaceae. In Duarte province in a secondary forest as part of a buffer area of the scientific reserve, 34 families represented by 66 species were recorded, most of which are arboreal (48.5%), and shrubby, herbal and climbing life forms (each 13.6%); trunk diameters of 5 - 68 cm and heights from 5 - 32 m. The most abundant families are Fabaceae, Poaceae, Myrtaceae, Melinaceae and Mimosaceae
Etablissement de facteurs d'émission azotés avec le modèle STICS en canne à sucre dans l'ensemble des contextes pédoclimatiques de l'île de La Réunion
No full textLes produits résiduaires organiques (PROs) constituent une source importante de fertilisants organiques pour la fertilisation durable des agroécosystèmes dans un contexte d'économie circulaire. Mais leur utilisation peut avoir des conséquences sur l'environnement liés aux pertes d'azote (NH3, N2O, NO3-), qui varient selon le climat, le sol et les pratiques. Cette étude a permis d'établir des facteurs d'émission azotés pour la culture de canne à sucre à La Réunion avec le modèle STICS récemment paramétré pour ce contexte pédoclimatique. Au total 3960 simulations ont été réalisé en croisant 44 unités TypTerres (UTT), 3 types de fertilisants (Urée, lisier, compost), 2 niveaux de dose (50 et 100% des besoins) et le tout sur 10 années de cultures. Les années de plantation et de repousse ont été simulées. La coupe a été simulée 12 mois après plantation. Les sorties du modèle ont consisté à quantifier l'absorption de l'azote par la plante, l'immobilisation, la lixiviation de NO3-, les émissions de N2O et la volatilisation de NH3. Les résultats obtenus montrent que la principale voie de perte pour l'urée est la volatilisation. Ceci est amplifié dans les sols alluvionnaires et les climats tropicaux secs. Le lisier présente des facteurs d'émissions de lixiviation du NO3- atteignant 27% dans les sols alluvionnaires et 12,5% sous les climats tropicaux humide. Le compost se distingue par une très forte immobilisation de l'azote (93%), ce qui permet de limiter les pertes par lixiviation mais en contrepartie de réduire l'absorption à court terme. La lixiviation du NO3- s'est révélé contrôlée davantage par le climat et la texture des sols. Les émissions de N2O les plus élevées ont été enregistrées pour les sols argileux. Au-delà de la quantification des émissions, ces travaux mettent en lumière certaines limites structurelles de STICS sur la prise en compte des effets dynamiques du vent sur la volatilisation, l'absence d'écoulement préférentiels pour la lixiviation, la prise en compte des cinétiques spécifiques aux communautés microbiennes pour la nitrification et la dénitrification. Ces limites ont permis de suggérer des améliorations du modèle. Les facteurs d'émission établis constituent une base de référence régionale qui sera utile dans les évaluations environnementales
Evaluating participatory processes in water and environmental policymaking: Framework and applications
Get PDFOur intervention will draw from 20 years of experience as researchers supporting the evaluation of participatory processes in policymaking in the field of water and environmental governance. We will detail the principles and theoretical framework that we are using, as well as case studies in two countries. The theoretical framework is part of the CoOPLAGE approach, developed by an interdisciplinary group of researchers and practitioners from Montpellier (France) and beyond (Hassenforder & Ferrand, 2024). CoOPLAGE is the French acronym for “Coupling Open and Participatory Tools to Let Actors Adapt for Environmental Management”. The main assumption underlying evaluation in the CoOPLAGE approach is that evaluation should support citizens and other actors when making decisions in a policy-process. We will argue that 12 principles can be applied for evaluation to support the transparency and accountability of public policies: useful, participative, subjective, early, reflexive, adaptive, fixed, open, simple, endogenous, mixed and plural. After presenting this theoretical framework, we will illustrate its application in two cases. In the Drôme region in France, citizens participated in the participatory process and in its evaluation towards the revision of the river basin management plan. In Tunisia, more than 4000 citizens participated in the elaboration of integrated territorial management plans in 6 rural territories. The evaluation of this process raised challenges in terms of numbers of people involved, diversity of data collected, multiplicity of evaluation objectives, etc. Our intervention will highlight the challenges and lessons learnt from these experiences
Comment co-construire des indicateurs pour la durabilité des nappes captives ?
Get PDFDans le cadre du projet DEESAC (Durabilité et exploitabilité des eaux souterraines des aquifères captifs ou sous couverture) financé par le programme OneWater, ce webinaire présente trois cas de gestion concertée des aquifères captifs en France et à l'international. Les trois cas présentés sont les suivants : - Les nappes de l'Astien (Hérault, France) - Le Grand Bassin Artésien (Australie) - Les nappes profondes de Gironde (France) L'étude menée dans le cadre du projet a permis d'analyser sur chaque cas : (i) l'historique de la gestion concertée des nappes captives et la façon dont les différents acteurs ont été progressivement impliqués, (ii) comment les objectifs de gestion durable ont été définis collectivement, ainsi que les indicateurs de bon état mis en place pour répondre à ces objectifs de gestion durable. La présentation a été suivie d'un temps d'échange entre gestionnaires, chercheurs et partenaires du projet
Phenotyping canopy-level photosynthetic responses to intermittent shading: beyond the daily light integral in multilayered cropping systems
Get PDFMultilayered cropping systems such as agrivoltaics, agroforestry, and intercropping create spatiotemporal light variability, including daily shade intermittence. While its physiological impacts are recognised, shade intermittence remains understudied and is not accounted for in crop models, which typically consider a daily light integral (DLI) to calculate growth. Beyond photosynthetic adjustments to rapid light changes, it also affects integrative traits such as plant morphology and reduces radiation use efficiency (RUE) compared to constant shading. In a recent study across 14 rice genotypes, intermittent shading compared to constant shading with the same DLI, significantly reduced yield and aboveground biomass. Source limitations were driven by the nonlinear light- assimilation response combined with a decrease in photosystem efficiency (ΦPSII and electron transport rates) under both low and high light levels. Crop responses were consistent among genotypes, but biomass and yield varied widely. These findings emphasise the need to consider not just DLI but also shading dynamics when phenotyping crop responses in partial shade. Moreover, plant responses to shade intermittence vary with shading intensity, frequency, and duration. This raises a key question: how can shading dynamics be integrated into phenotyping and modelling approaches? To address this, we combined canopy assimilation measurements (flux chamber) under four daily shading patterns, created with removable shade nets, and leaf-level fluorescence and gas exchange measurements (Li-6800) on two rice varieties. Objectives include observing canopy assimilation dynamics under various shading patterns, identifying traits relevant for phenotyping rice photosynthesis under intermittent shading, and determining shading pattern variables that explain these responses for consideration into modelling. First results provide insight into key traits for phenotyping rice performance under intermittent shade and identify shading pattern indexes explaining assimilation variation. This novel approach to phenotyping photosynthesis traits under intermittent shading opens new possibilities for improving genotype selection and optimising multilayered system design
Futurs de l'élevage dans les systèmes agri-alimentaires. Prospectives et évaluation multicritère de scénarios
Get PDFLe système alimentaire mondial fait face à trois grands défis : garantir la sécurité alimentaire, préserver l'environnement et améliorer la santé humaine. L'élevage, au croisement de ces enjeux, joue un rôle central. Toutefois, l'évolution des régimes alimentaires, la croissance démographique et les transformations des paysages diffèrent selon les régions du monde. Ces dynamiques soulèvent des questions sur la place de l'élevage dans les territoires, sa forme, ses impacts et les services qu'il peut rendre. Comment anticiper ces transformations et en évaluer les conséquences ? Une diversité de démarches prospectives menées dans des contextes variés (au Nord comme au Sud) et à différentes échelles (du local au global) est présentée dans cet ouvrage. Il explore l'articulation entre les méthodes qualitatives de (co-) construction de scénarios et les approches quantitatives de modélisation et d'évaluation. L'ouvrage interroge également le déroulement temporel du cycle prospective–modélisation–évaluation, l'identification des variables clés, l'usage des données, ainsi que la place des acteurs dans le processus, notamment en ce qui concerne l'appropriation des résultats pour orienter les décisions. Cet ouvrage est issu d'une école-chercheurs organisée par INRAE et le Cirad dans le cadre du réseau mixte technologique Macro-Élevage-Environnement (RMT MAELE). Il s'adresse à la communauté scientifique engagée dans des démarches interdisciplinaires. Il intéressera également les acteurs de l'agriculture, de l'environnement et de l'alimentation, ainsi que ceux impliqués dans le développement durable des territoires agricoles
Environmental conditions impact Cavendish banana agronomic traits more than genotype
Get PDFCropping practices used in banana production are currently shifting towards agroecological management, but the resulting performances of Cavendish banana cultivars need to be reassessed. This study aimed to gain insight into the impacts of the cultivar and cropping environment on the agronomic performances—in terms of agronomic traits—on a range of Cavendish cultivars. Twelve phenotypically contrasted cultivars were studied in five experimental cropping conditions in Guadeloupe. These conditions differed in terms of their black sigatoka management, fertilisation level and weed management strategy. The cultivar agronomic performances were assessed according to eight agronomic traits related to plant morphology and yield. Our results showed that the cropping conditions (environment) had a greater effect than the cultivars (genotype) on agronomic traits, while their interaction (GEI) had almost no effect. The potential nutritional limitation times (vegetative vs reproductive phases) also impacted the agronomic traits, in accordance with yield build-up components in banana plants. Moreover, there was a positive correlation between all traits, with no trade-offs. Finally, our findings showed that while cultivars tolerant to sub-optimal cropping conditions are essential, the system design and cropping practices are crucial to limit and buffer nutritional stresses and their impacts on banana growth and yield. Based on these results, we propose prospects for the design of cropping systems to improve productivity despite limiting growing environments