Regreening Africa enhances resilience in the Sahel and Horn of Africa by addressing climate change, land degradation, and food insecurity. Through a broad partnership network, the initiative scales context-appropriate land restoration by integrating trees and sustainable practices into farming and pastoral systems. Phase II expands efforts in Somalia, Ethiopia, Senegal, Nigeria, Ghana, Mali, and Niger, focusing on systems scaling for transformative change. Building on Phase I, this phase promotes agroforestry, FMNR, soil and water conservation, soil health improvement, grazing management, and energy-efficient cookstoves to boost land productivity and resilience, particularly in rangeland and mixed landscapes.
Tag: Agroforestry
Climate-growth relationships of Daniellia oliveri (Rolfe) Hutch. & Dalziel in the Sudanian zone of Mali, West Africa
Tree rings depend on seasonal variation in radial tree growth. Where they can be identified, their interannual variation may reflect climate variability. Compared to its use in temperate and boreal regions, tree-ring analysis has been less applied in tropical Africa, with weaker seasonality. Daniellia oliveri often forms the tallest trees in agroforestry parklands of the Sudanian savanna zone of Mali but its growth response to climate (rainfall, temperature) variability has not been documented. We analyzed six stem disks of D. oliveri and used standard dendrochronological methods to process the samples. Contrary to earlier literature likely based on more humid parts of the species distribution range, D. oliveri formed distinct growth ring boundaries in our study area. The mean annual radial growth was 2.73 ± 0.56 mm. All measured tree-ring series were successfully cross-dated with a GLK (Gleichläufigkeit) value of 76.3 ± 5.6. The final tree-ring chronology covers the period 1909-2021. After removing age-related growth trends, the tree-ring width index showed a significant relationship with records of annual rainfall (r2 = 0.46, n = 100 years, p < 0.001). The relationship between wet-season (June to September) precipitation and the residual chronology was slightly higher (r2 = 0.50, n = 100 years, p < 0.001). However, no significant correlation was found for temperature. These results imply that D. oliveri can be successfully used for dendrochronological studies with relevance for the management and restoration of the ecosystems in the Sudanian zone of West Africa, where long-term rainfall records are scarce.
The multidimensional performance of agroecology: what we know and what we are yet to learn
This opinion article argues that the debate surrounding the effectiveness of agroecology should move beyond questions of whether evidence exists and instead focus on identifying the remaining knowledge gaps needed to support evidence-based agroecological transitions. Drawing on a growing body of reviews, meta-analyses, and field studies, the authors highlight substantial evidence that agroecological practices, including crop rotation, intercropping, agroforestry, mulching, composting, cover cropping, and integrated crop–livestock systems, contribute positively to food security, agricultural productivity, farmers’ incomes, climate-change adaptation, biodiversity conservation, ecosystem services, and climate-change mitigation. Recent studies demonstrate that agroecological practices often outperform conventional systems in terms of soil carbon sequestration, biodiversity enhancement, income stability, and resilience while simultaneously contributing to multiple Sustainable Development Goals.
Allometric models for estimating fuelwood and above-ground wood dry mass of pruned Faidherbia albida trees in northern Cameroon
In Cameroon’s Sudano-Sahelian zone, rising fuelwood demand is jeopardising Faidherbia albida agroforestry parklands. Faced with these alarming pressures and ongoing climate challenges, evaluating sustainable management practices and the contribution of F. albida agroforestry parklands to climate change mitigation has become a pressing priority. In these agro-ecosystems, total and rotational crown pruning are common practices, traditionally aimed at fuelwood and livestock feed collection. However, its impact on the trade-off between leaf removal and pod production remains poorly documented, particularly regarding long-term fuelwood yield potential. This research aims to develop tools for estimating the above-ground wood dry mass of F. albida components in the context of their use as renewable fuelwood and their carbon storage potential. Allometric equations for the different tree components were developed using data from the most recent pruning event (2023) of F. albida trees that had undergone three complete crown-pruning cycles over the past two decades. The predictors used to estimate fuelwood and above-ground wood dry mass were diameter at breast height (D, in cm), crown area (Ca, in m²), and total tree height (H, in m). The best-performing equations for each tree components relied on structurally meaningful combinations of these variables: (i) D²Ca, capturing the combined influence of stem size and crown development for estimating fuelwood obtained after pruning (DWpr, R²adj = 0.84) and the total above-ground wood dry mass of F. albida (TDWb, R²adj = 0.85), corresponding to the sum of DWpr and the post-pruning wood dry mass remaining after pruning (DWUpr); and (ii) D, reflecting the effect of stem diameter for predicting DWUpr, (R²adj = 0.76). The best crown area-only models for predicting DWpr and TDWb showed strong explanatory power, with adjusted R² values of 0.82 and 0.64, respectively. The integration of structural characteristics visible from space, such as the tree crown area, provides promising prospects for large-scale bio-mass mapping using satellite images and remote sensing methods.
Ecohydrology of agroforestry systems
Agroforestry systems integrate trees with crops and/or livestock to provide food, fiber, and energy, along with multiple other ecosystem services. Trees have important ecohydrological functions and affect infiltration, runoff, and evapotranspiration, such that, when embedded within agricultural landscapes, they can contribute to the capacity of watersheds to provide clean and reliable water supply. The ecohydrological effects of trees, however, are mediated by their location and spatial configuration within the watershed—which varies by the type of agroforestry system—and the system’s species composition, structure, and management. Here, we describe the primary ecohydrological functions of trees and then review the current literature on the ecohydrology of eight common agroforestry systems. We show that most studies have focused on a single agroforestry system and very few address watershed scale implications. As a result, knowledge on how the ecological characteristics, configuration, spatial location, and management of agroforestry systems within the landscape affect hydrological processes across multiple scales is still limited. Thus, future studies should focus on addressing these knowledge gaps to better inform how agroforestry can provide a strategy for enhancing ecohydrological processes and watershed services.
Scaling & Enhancing Restoration Impact Through Gender Transformative Approaches
Regreening Africa enhances resilience in the Sahel and Horn of Africa by addressing climate change, land degradation, and food insecurity. Through a broad partnership network, the initiative scales context-appropriate land restoration by integrating trees and sustainable practices into farming and pastoral systems. Phase II expands efforts in Somalia, Ethiopia, Senegal, Nigeria, Ghana, Mali, and Niger, focusing on systems scaling for transformative change. Building on Phase I, this phase promotes agroforestry, FMNR, soil and water conservation, soil health improvement, grazing management, and energy-efficient cookstoves to boost land productivity and resilience, particularly in rangeland and mixed landscapes.
Climate-growth relationships of Daniellia oliveri (Rolfe) Hutch. & Dalziel in the Sudanian zone of Mali, West Africa
Tree rings depend on seasonal variation in radial tree growth. Where they can be identified, their interannual variation may reflect climate variability. Compared to its use in temperate and boreal regions, tree-ring analysis has been less applied in tropical Africa, with weaker seasonality. Daniellia oliveri often forms the tallest trees in agroforestry parklands of the Sudanian savanna zone of Mali but its growth response to climate (rainfall, temperature) variability has not been documented. We analyzed six stem disks of D. oliveri and used standard dendrochronological methods to process the samples. Contrary to earlier literature likely based on more humid parts of the species distribution range, D. oliveri formed distinct growth ring boundaries in our study area. The mean annual radial growth was 2.73 ± 0.56 mm. All measured tree-ring series were successfully cross-dated with a GLK (Gleichläufigkeit) value of 76.3 ± 5.6. The final tree-ring chronology covers the period 1909-2021. After removing age-related growth trends, the tree-ring width index showed a significant relationship with records of annual rainfall (r2 = 0.46, n = 100 years, p < 0.001). The relationship between wet-season (June to September) precipitation and the residual chronology was slightly higher (r2 = 0.50, n = 100 years, p < 0.001). However, no significant correlation was found for temperature. These results imply that D. oliveri can be successfully used for dendrochronological studies with relevance for the management and restoration of the ecosystems in the Sudanian zone of West Africa, where long-term rainfall records are scarce.
Scaling & Enhancing Restoration Impact Through Gender Transformative Approaches
Regreening Africa enhances resilience in the Sahel and Horn of Africa by addressing climate change, land degradation, and food insecurity. Through a broad partnership network, the initiative scales context-appropriate land restoration by integrating trees and sustainable practices into farming and pastoral systems. Phase II expands efforts in Somalia, Ethiopia, Senegal, Nigeria, Ghana, Mali, and Niger, focusing on systems scaling for transformative change. Building on Phase I, this phase promotes agroforestry, FMNR, soil and water conservation, soil health improvement, grazing management, and energy-efficient cookstoves to boost land productivity and resilience, particularly in rangeland and mixed landscapes.
Scaling & Enhancing Restoration Impact Through Gender Transformative Approaches
Regreening Africa enhances resilience in the Sahel and Horn of Africa by addressing climate change, land degradation, and food insecurity. Through a broad partnership network, the initiative scales context-appropriate land restoration by integrating trees and sustainable practices into farming and pastoral systems. Phase II expands efforts in Somalia, Ethiopia, Senegal, Nigeria, Ghana, Mali, and Niger, focusing on systems scaling for transformative change. Building on Phase I, this phase promotes agroforestry, FMNR, soil and water conservation, soil health improvement, grazing management, and energy-efficient cookstoves to boost land productivity and resilience, particularly in rangeland and mixed landscapes.
Scaling & Enhancing Restoration Impact Through Gender Transformative Approaches
Regreening Africa enhances resilience in the Sahel and Horn of Africa by addressing climate change, land degradation, and food insecurity. Through a broad partnership network, the initiative scales context-appropriate land restoration by integrating trees and sustainable practices into farming and pastoral systems. Phase II expands efforts in Somalia, Ethiopia, Senegal, Nigeria, Ghana, Mali, and Niger, focusing on systems scaling for transformative change. Building on Phase I, this phase promotes agroforestry, FMNR, soil and water conservation, soil health improvement, grazing management, and energy-efficient cookstoves to boost land productivity and resilience, particularly in rangeland and mixed landscapes.