Long-term effects of land use/land cover change on surface runoff in urban areas of Beijing, China

Zhongchang Sun,Yingkui Li,Xinwu Li,Wenxue Fu,Dongsheng Tang

doi:10.1117/1.jrs.8.084596

Abstract

The objective of this paper is to present a case study to derive land use/land cover (LULC) maps and investigate the long-term effects of LULC change on surface runoff in the fast urbanizing Beijing city. The LULC maps were derived from Landsat TM/ETM+ imagery (acquired in 1992, 1999, 2006, and 2009) using support vector machine method. A long-term hydrologic impact assessment model was applied to assess the impact of LULC change on surface runoff. Results indicated that the selected study area experienced rapid urbanization from 1992 to 2009. Because of urbanization, from 1992 to 2009, modeled runoff increased 30% for the whole area and 35% for the urban portion. Our results also indicated that the runoff increase was highly correlated with urban expansion. A strong relationship (R 2 =0.849 ) was observed between the impervious surface percent and the modeled runoff depth in the study area. In addition, a strong positive relationship was observed between runoff increase and percentage of urban areas (R 2 =0.997 for the whole area and R 2 =0.930 for the urban portion). This research can provide a simple method for policy makers to assess potential hydrological impacts of future urban planning and development activities.

Highlights

Land use/land cover (LULC) changes have direct impacts on the hydrological cycle and stream quality
Because we focused on urbanization, only urban-related classes, including high-/medium-/low-impervious surfaces, were utilized for accuracy assessment
Urban areas increased from 4.28% in 1992 to 12.78% in 2009, and residential areas increased from 3.21% in 1992 to 6.66% in 2009, while agricultural land areas decreased from 27.20% in 1992 to 11.44% in 2009

Summary

Introduction

Land use/land cover (LULC) changes have direct impacts on the hydrological cycle and stream quality. There are indirect impacts on climate and the subsequent impact of the altered climate on the waters.[1] LULC changes have been treated as one of the most important and sensitive factors for global environmental change. Urbanization is a major force that is driving LULC changes. Increased impervious surface percentage in urbanized areas can reduce the time of runoff and increase the peak discharges of stream flow, resulting in large and more frequent incidents of flooding.[1,2] In addition, because of the pollutants in runoff and sediments, the increase of impervious surfaces degrades stream quality.[2,3] urbanized areas are increasingly susceptible to flooding under high precipitation conditions.[4]

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Conclusion