Simulation of Potential Suitable Distribution of Endangered Waterfowl and Its Gap Analysis of National Nature Reserves in Beijing-Tianjin-Hebei Region under Climate Change Scenarios
Determining the potential suitable distributions of endangered waterfowl species and protecting these areas have a great impact on maintaining the diversity of waterfowl species,protecting threatened waterfowl and improving wetland quality.As one of the most promising area of economic growth,the number of waterfowl in the Beijing-Tianjin-Hebei Region has greatly changed recently.Based on the GIS platform and MaxEnt model,we used occurrence sites of the endangered waterfowl in 2015 as input data,and analyzed potential suitable distribution of 9 endangered waterfowl species under different climate change in 2015 and 2050.Next,we quantitatively identified the main driving factors and their corresponding contribution rates for each water bird.Last,we used spatial analysis tool to do the gap analysis of nature reserves (NRs) for the whole region and each province.The results showed that:(1) Potential suitable area of Larus relictus,Ciconia boyciana and Ciconia nigra was larger than the other 6 species.Potential suitable distributions of Larus relictus and Ciconia boyciana were mainly focused on the coast of the Bohai Sea and south-central part of Beijing,while Ciconia nigra are mainly focused on Fangshan district and northeast of Beijing.(2) All of the potential suitable areas of 9 endangered waterfowl under 3 climate scenarios were larger than baseline situation in 2015.Increasing rates of RCP2.6,RCP4.5 and RCP8.5 (which represent the low,median and high values of emission concentration of CO_2) were 96.24%,103.94% and 65.51%,respectively.Their spatial distributions expanded toward the southwest and northeast.(3) The coverage of national NRs for potential suitable area and hot spot of 9 endangered water birds was low.Compared with Tianjin,the coverage of potential suitable area and hot spot in Hebei and Beijing was exceptionally low.(4) At the whole regional scale,the coverage of potential suitable areas in descending order was:baseline scenario (1.26%) >RCP8.5 (1.11%) >RCP2.6 (0.70%) >RCP4.5 (0.29%),the coverage of hot spot in descending order was:RCP4.5 (0.83%) >baseline scenario (0.77%) >RCP8.5 (0.08%) >RCP2.6 (0).This study takes a single water bird unit,and synthesizes potential suitable distributions of 9 species of endangered waterfowl under 3 climate change scenarios,which can effectively reflect the coverage of NRs for endangered waterfowl.The spatial pattern of NRs in the Beijing-Tianjin-Hebei Region needs to be adjusted in the future.