In Ethiopia, the natural forests with the occurrence of wild Arabica coffee gene pools are under constant threats, largely due to anthropogenic activities. The study was conducted to compare the variability among the ...In Ethiopia, the natural forests with the occurrence of wild Arabica coffee gene pools are under constant threats, largely due to anthropogenic activities. The study was conducted to compare the variability among the wild arabica coffee genotypes in biomass assimilation and allocation patterns under varying light and irrigation conditions at the Jimma Research Center, southwestern Ethiopia. The treatments included irradiance (moderate and full sunlight), irrigation (well watered and water stressed) regimes and twelve coffee genotypes of different geographical areas. One-year-old seedlings were used to record dry mass of leaves, main stem, primary branches and root growth. Each organ was separately oven-dried and total dry matter production and allocation patterns were measured and analyzed. The results depicted highly significant differences between the contrasting irradiance and irrigation regimes as well as among coffee genotypes. Significantly the lowest and highest stems dry mass values recorded for Berhane-Kontir and Harenna genotypes, respectively. Most accessions had relatively lower assimilations in shade as compared to full sun light conditions. Likewise, coffee seedlings significantly differed in root dry mass and root to shoot ratio, dry matter partitioning due to the main and combined treatment effects. Overall, total biomass assimilation and partitioning were higher for unshaded, water stressed and Harenna genotypes from the respective treatment groups. Conversely, leaf dry matter, leaf share was significantly high under moderate shade environments. The total dry matter share varied for the seedling growth parts (root = 22%, leaf = 35%, stem = 43% and whole shoot = 78%). The root growth followed the order of Harenna > Yayu > Bonga > Berhane-Kontir populations. The reverse was true for the leaf and whole-shoots, demonstrating the completion between above and below ground growth parts and thus the need to consider both dry matter assimilation and partitioning patterns in identifying desirable genotypes and optimum environments for future breeding program in Ethiopia.展开更多
Land rehabilitation by area exclosure was the fastest and moderate approach of recovering degraded sites.However,the effect of exclosure on woody species parameters in Jabitehnan district,north-western Ethiopia has no...Land rehabilitation by area exclosure was the fastest and moderate approach of recovering degraded sites.However,the effect of exclosure on woody species parameters in Jabitehnan district,north-western Ethiopia has not been investigated.Therefore,the current study was conducted(i)to assess and compare diversity,composition and density of woody species in exclosure and adjacent open lands,and(ii)to analyze population structure as well as regeneration status of woody species.A random sampling method was employed to select a total of 40 sample plots(50m*50m).A total of 8 parallel transect lines were used inside and outside the exclosure land in each site for consecutive(50m interval)plot establishment.Species diversity was 1.7 and 3.03 for WG,1.1 and 2.94 for GW open and exclosures,respectively.Population structure of woody species in exclosures of both sites exhibited an inverted J shape which indicates good regeneration status,while in adjacent open grazing land it exhibited partial bell shape.Generally,exclosure provides various biophysical benefits better than adjacent open grazing lands.It is recommended to protect degraded lands by exclosure via integrating appropriate species and convert their diversity into use so as to develop their potential benefits on land restoration.展开更多
Assessment of ecological fitness of woody species across land use is critical issues in degraded land restoration.However,little is known about AGBC stored capacity,important value and distribution index of woody spec...Assessment of ecological fitness of woody species across land use is critical issues in degraded land restoration.However,little is known about AGBC stored capacity,important value and distribution index of woody species grows in exclosure and adjacent open lands.Therefore,this research is aimed to(i)analyse impact of exclosure on AGBC(ii)ecological fit species.A random sampling method was employed.Forty sample plots(50m*50m)were used.AGBC stocks(mean±SE)of woody species in adjacent open grazing and exclosure land use of GW site was 0.11±0.07 and 1.24±0.27Mg ha^(-1) respectively.While in adjacent open grazing and exclosure land use of WG site,the value was 0.27±0.03 and 2.79±0.27Mgha^(-1) respectively.In both site exclosure land uses,the proportion of rare,occasional and common woody species were better than their adjacent open grazing land.Cupressus lustanica from open grazing and Vernonia auriculifera from exclosure land use of WG as well as Croton macrostachyus from open grazing and Leucaena leucocephala fromexclosure land use of GWsite were recorded as top ecologically fit species.It is recommended to protect degraded lands via integrating ecologically adapted native species and fully used their diversity to achieve the potential benefits of land restoration.展开更多
文摘In Ethiopia, the natural forests with the occurrence of wild Arabica coffee gene pools are under constant threats, largely due to anthropogenic activities. The study was conducted to compare the variability among the wild arabica coffee genotypes in biomass assimilation and allocation patterns under varying light and irrigation conditions at the Jimma Research Center, southwestern Ethiopia. The treatments included irradiance (moderate and full sunlight), irrigation (well watered and water stressed) regimes and twelve coffee genotypes of different geographical areas. One-year-old seedlings were used to record dry mass of leaves, main stem, primary branches and root growth. Each organ was separately oven-dried and total dry matter production and allocation patterns were measured and analyzed. The results depicted highly significant differences between the contrasting irradiance and irrigation regimes as well as among coffee genotypes. Significantly the lowest and highest stems dry mass values recorded for Berhane-Kontir and Harenna genotypes, respectively. Most accessions had relatively lower assimilations in shade as compared to full sun light conditions. Likewise, coffee seedlings significantly differed in root dry mass and root to shoot ratio, dry matter partitioning due to the main and combined treatment effects. Overall, total biomass assimilation and partitioning were higher for unshaded, water stressed and Harenna genotypes from the respective treatment groups. Conversely, leaf dry matter, leaf share was significantly high under moderate shade environments. The total dry matter share varied for the seedling growth parts (root = 22%, leaf = 35%, stem = 43% and whole shoot = 78%). The root growth followed the order of Harenna > Yayu > Bonga > Berhane-Kontir populations. The reverse was true for the leaf and whole-shoots, demonstrating the completion between above and below ground growth parts and thus the need to consider both dry matter assimilation and partitioning patterns in identifying desirable genotypes and optimum environments for future breeding program in Ethiopia.
文摘Land rehabilitation by area exclosure was the fastest and moderate approach of recovering degraded sites.However,the effect of exclosure on woody species parameters in Jabitehnan district,north-western Ethiopia has not been investigated.Therefore,the current study was conducted(i)to assess and compare diversity,composition and density of woody species in exclosure and adjacent open lands,and(ii)to analyze population structure as well as regeneration status of woody species.A random sampling method was employed to select a total of 40 sample plots(50m*50m).A total of 8 parallel transect lines were used inside and outside the exclosure land in each site for consecutive(50m interval)plot establishment.Species diversity was 1.7 and 3.03 for WG,1.1 and 2.94 for GW open and exclosures,respectively.Population structure of woody species in exclosures of both sites exhibited an inverted J shape which indicates good regeneration status,while in adjacent open grazing land it exhibited partial bell shape.Generally,exclosure provides various biophysical benefits better than adjacent open grazing lands.It is recommended to protect degraded lands by exclosure via integrating appropriate species and convert their diversity into use so as to develop their potential benefits on land restoration.
基金The first author acknowledges the financial support by Federal Democratic Republic of EthiopiaCommission of Environment,Forest and Climate changeEthiopian Environment and Forest Research Institute.
文摘Assessment of ecological fitness of woody species across land use is critical issues in degraded land restoration.However,little is known about AGBC stored capacity,important value and distribution index of woody species grows in exclosure and adjacent open lands.Therefore,this research is aimed to(i)analyse impact of exclosure on AGBC(ii)ecological fit species.A random sampling method was employed.Forty sample plots(50m*50m)were used.AGBC stocks(mean±SE)of woody species in adjacent open grazing and exclosure land use of GW site was 0.11±0.07 and 1.24±0.27Mg ha^(-1) respectively.While in adjacent open grazing and exclosure land use of WG site,the value was 0.27±0.03 and 2.79±0.27Mgha^(-1) respectively.In both site exclosure land uses,the proportion of rare,occasional and common woody species were better than their adjacent open grazing land.Cupressus lustanica from open grazing and Vernonia auriculifera from exclosure land use of WG as well as Croton macrostachyus from open grazing and Leucaena leucocephala fromexclosure land use of GWsite were recorded as top ecologically fit species.It is recommended to protect degraded lands via integrating ecologically adapted native species and fully used their diversity to achieve the potential benefits of land restoration.
