The primary objective of this study is to assess the impact of climate change on the current and future spatial distribution of areas suitable for the growth of Senegalia senegal, a forest species of significant agro-...The primary objective of this study is to assess the impact of climate change on the current and future spatial distribution of areas suitable for the growth of Senegalia senegal, a forest species of significant agro-ecological and socio-economic importance. To achieve this objective, the MaxEnt (Maximum Entropy) model was utilized, incorporating species presence points alongside bioclimatic variables. To project future distributions, three climatic models-CCCMA, HadCM3, and CSIRO were employed under the A2 scenario to predict the species’ distribution by the year 2050. Currently, habitats highly favorable for the conservation of the species are situated in the Sahelo-Sudanian and Sudanian zones, accounting for 6.81% of the national territory. All models forecast a substantial increase in habitats highly favorable for the future conservation of S. senegal, with a total expected growth of 448.9%. Conversely, moderately favorable and unfavorable habitats are predicted to decrease by 106.26% and 78.59%, respectively. These findings provide crucial data for the long-term conservation strategy of this species, which holds significant ecological and agronomic potential for the Sahelian region.展开更多
Since 2003, the sites of the national environmental monitoring system （DNSE） of Niger, set up by the long term ecological monitoring observatories network （ROSELT） with the support of the Sahel and Sahara Observat...Since 2003, the sites of the national environmental monitoring system （DNSE） of Niger, set up by the long term ecological monitoring observatories network （ROSELT） with the support of the Sahel and Sahara Observatory （OSS）, were used to collect ecological data with harmonized methods for spatio-temporal comparisons purpose. Floristic and phytoecological data were collected using the phytosociological methodology of Braun-Blanquet （1932）. Ecosystem vital attributes used included the specific diversity, alpha diversity, equidistribution, biological types and herbaceous phytomass. At the whole system scale, the analysis revealed that the specific diversity, the alpha diversity and the phytomass values were higher in less disturbed biotopes of the north soudanian and south sahelian bioclimates where the rainfall rate is relatively high. Regarding the north sahelian and saharian bioclimates, the topography may play a critical role in the redistribution of this phytodiversity. Besides, the distribution of the biological types showed the prevalence of therophytes （56.8 ± 11%） regardless of the bioclimate and, to a lesser extent, the perennial species （26.5 ± 7.3%）, the later group showing higher values for the north soudanian bioclimate.展开更多
文摘The primary objective of this study is to assess the impact of climate change on the current and future spatial distribution of areas suitable for the growth of Senegalia senegal, a forest species of significant agro-ecological and socio-economic importance. To achieve this objective, the MaxEnt (Maximum Entropy) model was utilized, incorporating species presence points alongside bioclimatic variables. To project future distributions, three climatic models-CCCMA, HadCM3, and CSIRO were employed under the A2 scenario to predict the species’ distribution by the year 2050. Currently, habitats highly favorable for the conservation of the species are situated in the Sahelo-Sudanian and Sudanian zones, accounting for 6.81% of the national territory. All models forecast a substantial increase in habitats highly favorable for the future conservation of S. senegal, with a total expected growth of 448.9%. Conversely, moderately favorable and unfavorable habitats are predicted to decrease by 106.26% and 78.59%, respectively. These findings provide crucial data for the long-term conservation strategy of this species, which holds significant ecological and agronomic potential for the Sahelian region.
文摘Since 2003, the sites of the national environmental monitoring system （DNSE） of Niger, set up by the long term ecological monitoring observatories network （ROSELT） with the support of the Sahel and Sahara Observatory （OSS）, were used to collect ecological data with harmonized methods for spatio-temporal comparisons purpose. Floristic and phytoecological data were collected using the phytosociological methodology of Braun-Blanquet （1932）. Ecosystem vital attributes used included the specific diversity, alpha diversity, equidistribution, biological types and herbaceous phytomass. At the whole system scale, the analysis revealed that the specific diversity, the alpha diversity and the phytomass values were higher in less disturbed biotopes of the north soudanian and south sahelian bioclimates where the rainfall rate is relatively high. Regarding the north sahelian and saharian bioclimates, the topography may play a critical role in the redistribution of this phytodiversity. Besides, the distribution of the biological types showed the prevalence of therophytes （56.8 ± 11%） regardless of the bioclimate and, to a lesser extent, the perennial species （26.5 ± 7.3%）, the later group showing higher values for the north soudanian bioclimate.
