Niger: Ecosystems
Climate change is expected to have a significant influence on the ecology and distribution of tropical ecosystems, though the magnitude, rate and direction of these changes are uncertain [31]. With rising temperatures and increased frequency and intensity of droughts, wetlands and riverine systems are increasingly at risk of being converted to other ecosystems, with plant populations being succeeded and animals losing habitats. Increased temperatures and droughts can also impact succession in forest systems while concurrently increasing the risk of invasive species, all of which affect ecosystems. In addition to these climate drivers, low agricultural productivity and population growth might motivate further agricultural expansion, resulting in increased deforestation, land degradation and forest fires, all of which will impact animal and plant biodiversity.
Species richness
Model projections of species richness (including amphibians, birds and mammals) and tree cover for Niger are shown in Figure 15 and 16, respectively. The models applied for this analysis show particularly strong agreement on the development of species richness under RCP6.0: Northern Niger is expected to gain up to 20 % of animal species due to climate change, while southern Niger is expected to lose around 20 %.
Tree cover
With regard to tree cover, model results are far less certain and of low magnitude. For RCP2.6, there is model agreement in very few areas showing no change in tree cover. Under RCP6.0, tree cover is projected to increase by only 0.5 % in central Niger by 2080 (Figure 16).
It is important to keep in mind that the model projections exclude any impacts on biodiversity loss from human activities such as land use, which have been responsible for significant losses of global biodiversity in the past, and are expected to remain its main driver in the future [32]. In recent years, Niger’s vegetation has experienced profound disturbances due to population pressure and increasing demand for farmland and firewood, leaving large parts of Niger’s soils severely degraded [25]. According to an ICRISAT report, around 80 000 to 120 000 ha of land are annually degraded in Niger [33].
References
[31] T. M. Shanahan, K. A. Hughen, N. P. McKay, J. T. Overpeck, C. A. Scholz, W. D. Gosling, C. S. Miller, J. A. Peck, J. W. King, and C. W. Heil, “CO2 and fire influence tropical ecosystem stability in response to climate change,” Nat. Publ. Gr., no. July, pp. 1–8, 2016.
[32] IPBES, “Report of the Plenary of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services on the work of its seventh session,” n.p., 2019.
[33] B. V. Bado, P. Savadogo, and M. L. S. Manzo, “Restoration of Degraded Lands in West Africa Sahel: Review of Experiences in Burkina Faso and Niger,” n.p., 2016.