The Yellow River Source National Park(YRSP)is one of the most sensitive and fragile ecological regions in the world.The historical intensive grazing and climate change have resulted in ecological degradation that thre...The Yellow River Source National Park(YRSP)is one of the most sensitive and fragile ecological regions in the world.The historical intensive grazing and climate change have resulted in ecological degradation that threatens the wildlife and livestock.Exploring the sustainable strategy is urgent for policy makers to meet the demands for wild ungulates and livestock.In our study,the grassland ecological carrying capability(GECC)was assessed based on the updated grass-livestock balance that considered the grass competition from wild ungulates.The balances between grass and livestock,and GECC and grassland pressure index(GPI)in the YRSP were measured through overlay analysis and geostatistic analysis.The results showed that:(1)the ratio of livestock to wild ungulates in the research area was approximately 4.56:1,in which the proportion of livestock was 81.75%and the actual number of livestock was 33.84×104 standard sheep units;(2)Under the scenario of minimum grazing utilisation rate,the theoretical grazing capacity and GECC were 37.83×104 standard sheep units and−0.13,respectively.Under the maximum grazing utilisation rate,the theoretical grazing capacity and GECC were 41.93×104 standard sheep units and−0.21,respectively.Since GECC in both scenarios were both less than 0,the grassland was considered to be in surplus and the livestock was not overloaded.However,GPI in the two scenarios were 0.87 and 0.79,respectively,both of which exceeded the warning line of 0.70.Based on GECC,we recommend that the sustainable strategy in YRSP is either to increase the supplementary feeding about 6.40×104 standard sheep units or reduce the grazing livestock by about 3.50×10^(4) standard sheep units.展开更多
桂南沿海诸河流域人口密度大,土地垦殖率高,降雨充沛且暴雨、台风天气多发,降雨侵蚀力极高,水土流失问题是当地最严重的生态环境问题之一。鉴于此,以土壤侵蚀通用方程USLE为基础,利用我国已有的水土流失各个因子的研究成果,选取最适合...桂南沿海诸河流域人口密度大,土地垦殖率高,降雨充沛且暴雨、台风天气多发,降雨侵蚀力极高,水土流失问题是当地最严重的生态环境问题之一。鉴于此,以土壤侵蚀通用方程USLE为基础,利用我国已有的水土流失各个因子的研究成果,选取最适合桂南沿海诸河流域的因子计算方法,定量评估该流域土壤侵蚀情况,土壤侵蚀空间分布与地形地貌、土地利用类型以及人工桉树林等因子的关系。结果表明:流域土壤侵蚀整体呈现范围广、侵蚀破碎等特点,流域平均侵蚀模数146.93 t km^(-2)a^(-1),土壤年均侵蚀总量为360.67×10~4 t,从空间分布上看,侵蚀主要集中大风江和防城江流域。合理开展5°~25°旱地及桉树的种植方式,为构建良好的广西桂南地区农业生态发展、水土流失治理起到促进作用。展开更多
基金funded by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA23060601)National Natural Science Foundation of China (U20A2088)+2 种基金Monitoring and Warning Program for Resources and Environment Carrying Capability in Sichuan Province (Grant No. ZXGH201709)Land space planning of Sichuan Province (2019-2035)Ecological restoration planning of land space in Sichuan Province (20212035)
文摘The Yellow River Source National Park(YRSP)is one of the most sensitive and fragile ecological regions in the world.The historical intensive grazing and climate change have resulted in ecological degradation that threatens the wildlife and livestock.Exploring the sustainable strategy is urgent for policy makers to meet the demands for wild ungulates and livestock.In our study,the grassland ecological carrying capability(GECC)was assessed based on the updated grass-livestock balance that considered the grass competition from wild ungulates.The balances between grass and livestock,and GECC and grassland pressure index(GPI)in the YRSP were measured through overlay analysis and geostatistic analysis.The results showed that:(1)the ratio of livestock to wild ungulates in the research area was approximately 4.56:1,in which the proportion of livestock was 81.75%and the actual number of livestock was 33.84×104 standard sheep units;(2)Under the scenario of minimum grazing utilisation rate,the theoretical grazing capacity and GECC were 37.83×104 standard sheep units and−0.13,respectively.Under the maximum grazing utilisation rate,the theoretical grazing capacity and GECC were 41.93×104 standard sheep units and−0.21,respectively.Since GECC in both scenarios were both less than 0,the grassland was considered to be in surplus and the livestock was not overloaded.However,GPI in the two scenarios were 0.87 and 0.79,respectively,both of which exceeded the warning line of 0.70.Based on GECC,we recommend that the sustainable strategy in YRSP is either to increase the supplementary feeding about 6.40×104 standard sheep units or reduce the grazing livestock by about 3.50×10^(4) standard sheep units.
文摘桂南沿海诸河流域人口密度大,土地垦殖率高,降雨充沛且暴雨、台风天气多发,降雨侵蚀力极高,水土流失问题是当地最严重的生态环境问题之一。鉴于此,以土壤侵蚀通用方程USLE为基础,利用我国已有的水土流失各个因子的研究成果,选取最适合桂南沿海诸河流域的因子计算方法,定量评估该流域土壤侵蚀情况,土壤侵蚀空间分布与地形地貌、土地利用类型以及人工桉树林等因子的关系。结果表明:流域土壤侵蚀整体呈现范围广、侵蚀破碎等特点,流域平均侵蚀模数146.93 t km^(-2)a^(-1),土壤年均侵蚀总量为360.67×10~4 t,从空间分布上看,侵蚀主要集中大风江和防城江流域。合理开展5°~25°旱地及桉树的种植方式,为构建良好的广西桂南地区农业生态发展、水土流失治理起到促进作用。