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.
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.
Impacts of landscape restoration and long-term land use change on ecosystem services: Evidence from a case study in Ethiopia
Land degradation threatens food security, water resources, and biodiversity by eroding soil health and productivity. In Ethiopia, restoration initiatives like exclosures are widely implemented, yet most studies fail to integrate plot-level ecological evidence with landscape-scale land use and land cover (LULC) dynamics. Furthermore, few studies combine these biophysical trends with long-term economic valuation of ecosystem services (ES) and local knowledge to quantify ES trade-offs. Using the Sire-Dodota district of Ethiopia, as a case study, we (i) evaluated the localized ecological performances of communal exclosures relative to LULC-driven ecosystem service (ES) changes, (ii) quantified spatial and temporal (22 years) LULC impacts on ecosystem service values (ESVs), and (iii) assessed community perceptions of restoration outcomes. We combined vegetation inventories, spatial analysis, household surveys, focus group discussions, and value transfer methods across plot and landscape scales. Our results reveal a clear socio-ecological paradox across scales. At the plot-scale, community-managed exclosures significantly enhanced biomass accumulation and biodiversity, establishing a robust empirical baseline for ecological recovery. At the landscape scale, however, LULC-based ESVs increased over 22 years, driven by gains of US$80.6 million from agricultural lands and US$1.3 million from forest lands, alongside a US$3.4 million decline in shrubland ESVs. These increases are potential values rather than realized ecosystem service flows, masking systemic losses in regulating and supporting services as short-term agricultural expansion dominates valuation outcomes. Social data from 393 households strongly corroborate these patterns. While communities consistently recognized localized ecological recovery, they favored agroforestry integration over static exclosures to offset high opportunity costs of restricted access. Together, these findings caution against reliance on uncontextualized macro-scale economic indicators and underscore the need for integrated, multifunctional landscape strategies that align ecological recovery with livelihood needs. We, therefore, recommend establishing a national, open-access ESV meta-database linked to Ethiopia’s Land Degradation Neutrality (LDN) targets, alongside future multi-decadal monitoring of below-ground carbon and soil biodiversity, and the cost-benefit performance of blended finance restoration models.
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.
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.
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.
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.