CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Int J Environ Res Public Health. 2018 Apr 17;15(4):775. doi: 10.3390/ijerph15040775.
Urbanization is one of the most widespread anthropogenic activities, which brings a range of physical and biochemical changes to hydrological system and processes. Increasing direct runoff caused by land use change has become a major challenge for urban ecological security. Reliable prediction of the quantity and rate of surface runoff is an inherently difficult and time-consuming task for large ungauged urban areas. In this study, we combined Geographic Information System and remote sensing technology with an improved Soil Conservation Service curve number model to evaluate the effects of land use change on direct runoff volume of the four-ring area in Shenyang, China, and analyzed trends of direct runoff at different scales. Through analyzing trends of direct runoff from 1984 to 2015 at different scales, we explored how urbanization and other potential factors affect direct runoff changes. Total direct runoff volume increased over time, and trends varied from the inner urban area to suburban area. Zones 1 and 2 had a tendency toward decreasing direct runoff volume and risks, while Zones 3 and 4 showed gradual increases at both regional and pixel scales. The most important influence on direct runoff change was urban surface change caused by urbanization. This study presents a framework for identifying hotspots of runoff increase, which can provide important guidance to urban managers in future green infrastructure planning, in the hopes of improving the security of urban water ecological patterns.
城市化是最广泛的人为活动之一，它给水文系统和过程带来了一系列物理和生化变化。土地利用变化导致的径流量增加，已成为城市生态安全的主要挑战。对于大面积未测地区，可靠地预测地表径流量的数量和速率是一项具有内在难度和耗时的任务。在这项研究中，我们结合地理信息系统和遥感技术以及改进的土壤保持服务曲线数模型，评估了土地利用变化对中国沈阳四环地区直接径流量的影响，并分析了不同尺度的直接径流动态。通过分析不同尺度下 1984 年至 2015 年直接径流量的趋势，我们探讨了城市化和其他潜在因素如何影响直接径流量的变化。总的直接径流量随时间增加，趋势从市区到郊区有所不同。区域 1 和 2 的直接径流量呈减少趋势，风险降低，而区域 3 和 4 在区域和像素尺度上均呈逐渐增加趋势。对直接径流变化影响最大的是城市化引起的城市地表变化。本研究提出了一种识别径流增加热点的框架，可为未来绿色基础设施规划中的城市管理者提供重要指导，以提高城市水生态格局的安全性。
