State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 818 South Beijing Rd, Urumqi, 830011, China; Key Laboratory of Soil and Water Conservation and Ecological Restoration in Jiangsu Province, Co-Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, China.
J Environ Manage. 2022 Oct 1;319:115708. doi: 10.1016/j.jenvman.2022.115708. Epub 2022 Jul 10.
Human activities cause widespread changes in landscape composition, which can affect ecosystem services produced by these landscapes. It is usually believed that ecosystem services can be maximized only when we eliminate all human activities. However, this belief is not the case, at least in dryland ecosystems. Here, a gradient of human activity intensity was used to investigate changes in the value of ecosystem services over 30-years of land-use change between 1990 and 2020 in the arid Sangong River watershed of northwest China. Spatial analyses were performed to determine how the value of dryland ecosystem services changed with human activity intensity. Stepwise regressions and linear programming models were also performed to examine how to optimize the value of ecosystem services (i.e., regulating services, provisioning services, supporting services, and cultural services). We found that landscapes of the Sangong River watershed became increasingly fragmented and that human activities gradually intensified, but the value of ecosystem services fluctuated rather than linearly decreasing over the past 30 years. Specifically, a unimodal relationship was observed between human activities and ecosystem services. The peak value of ecosystem services was 5799 USD ha yr under intermediate human activity intensity (i.e., human footprint index ranged from 0.2 to 0.4 at a scale of one). Gross domestic product (GDP) per capita, population, and water consumption were the three most important driving factors of human activities and ecosystem services. Our results suggest that intermediate human activities may maximize dryland ecosystem services in long-term land-use change at the watershed scale, and highlight the importance of regulating economic development, population, and water consumption for the management of dryland ecosystem services.
人类活动导致景观组成发生广泛变化，从而影响这些景观产生的生态系统服务。通常认为，只有消除所有人类活动，才能最大限度地发挥生态系统服务的作用。然而，这种观点并不正确，至少在旱地生态系统中并非如此。在这里，利用人类活动强度梯度，研究了 1990 年至 2020 年 30 年来土地利用变化对中国西北三工河流域干旱区生态系统服务价值的影响。进行了空间分析，以确定旱地生态系统服务价值随人类活动强度的变化情况。还进行了逐步回归和线性规划模型分析，以检验如何优化生态系统服务的价值（即调节服务、供应服务、支持服务和文化服务）。我们发现，三工河流域的景观变得越来越破碎，人类活动逐渐加剧，但在过去 30 年中，生态系统服务的价值波动而非线性下降。具体来说，在人类活动与生态系统服务之间观察到单峰关系。在中等人类活动强度下（即，在 1 尺度上的人类足迹指数范围为 0.2 至 0.4），生态系统服务的峰值价值为 5799 美元公顷年。人均国内生产总值（GDP）、人口和耗水量是人类活动和生态系统服务的三个最重要驱动因素。我们的结果表明，在流域尺度的长期土地利用变化中，中等人类活动可能会使旱地生态系统服务最大化，并强调调节经济发展、人口和耗水量对于旱地生态系统服务管理的重要性。
