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
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.
Papua New Guinea Community tree nursery management guide
Welcome to the Papua New Guinea Community tree nursery management guide, a practical resource designed to support individuals, groups and communities to establish and manage successful plant nurseries. Whether you are starting from scratch or looking to improve your existing nursery, this guide provides step-by-step information tailored to local conditions and needs. This guide, while providing general rules and advice for nursery setting and management, is focused on the Bismarck Forest Corridor, which is an important high-integrity forest area bridging the provinces of Chimbu, Eastern Highlands, Madang and Jiwaka, a mountain region known as the Bismarck Range that extends upwards into Mount Wilhelm, Papua New Guinea’s highest peak (4 509 m above sea level).
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.
Agroforestry Practices for Woody Species Diversity and Woody Biomass Carbon Stock Enhancement in Northwestern Tigray, Ethiopia
Agroforestry plays an indispensable role in biodiversity conservation and ecosystem services. However, research on the ecological roles of different agroforestry practices in northwestern Tigray remains limited. This study to investigate the role of three agroforestry practices: homestead, parkland and woodlot in enhancing biodiversity and woody biomass carbon stock. A total of 68 sample plots representing 37 plots of parkland, 25 homestead, and 6 woodlots, were established from the purposively selected sites and households. 38 woody species from 22 families and 36 genera were recorded. Among these species, 26% were recorded in homestead, while 36.8% shared between homestead and parkland, and 18.4% across all land use types. Indigenous species accounted for 57.9%, with exotics represented 36.84% and invasive species 5.26%. The highest species diversity was found in homestead (H’ = 1.36), with significant variation among agroforestry types (p = 0.011). The total woody biomass were 32.36 ± 5.26, 17.74 ± 7.71 and 4.62 ± 0.76 Mg C ha-1 in homestead, woodlot and parkland agroforestry respectively. Cordia africana and Faidherbia albida and Ziziphus spina -christi were dominant in homestead and parkland agroforestry land use, whereas Eucalyptus camaldulensis and Acacia lahai dominated in the woodlots. Population structure analysis revealed low seedling regeneration in parklands due to agricultural disturbances. Woodlots in the study area are mostly established in productive farmlands thereby increasing competition with food production. Despite the competition of woodlots with agricultural crops for the productive lands, the findings generally indicate that homestead agroforestry is effective in enhancing ecological sustainability and mitigate climate change impacts. Thus, promoting agroforestry and proper woodlot establishment through engaging communities are essential for fostering community well-being and ensuring sustainable conservation of biodiversity.
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.