重庆市主城区土地利用变化对地表径流的影响
田 甜1, 牟凤云1, 王俊秀1, 赵灵晰2, 陈 林1, 李秋彦1

(1.重庆交通大学 建筑与城市规划学院, 重庆 400074; 2.国家信息中心 公共技术服务部, 北京 100045)

重庆市主城区; 土地利用变化; SCS模型; 地表径流

Impact of Land Use Change on Surface Runoff in the Main Urban Area of Chongqing
TIAN Tian1, MOU Fengyun1, WANG Junxiu1, ZHAO Lingxi2, CHEN Lin1, LI Qiuyan1

(1.School of Architecture and Urban Planning, Chongqing Jiaotong University, Chongqing 400074, China; 2.China Mobile Communications Group Department of State Information Center, Public Technology Service, Beijing 100045, China)

main urban area of Chongqing City; land use change; SCS model; surface runoff

备注

为了分析重庆市主城区土地利用变化对地表径流的影响,基于SCS水文模型遴选土地利用、降雨、土壤类别等相关数据,模拟前期土壤湿润程度正常状态(AMCⅡ)下枯水期、平水期、丰水期地表径流,从各土地利用类型的产流能力、径流系数及景观格局等分析了土地利用变化对地表径流的影响。结果表明:(1)2000—2015年,重庆市主城区土地利用类型以耕、林地为主,占比持续下降,耕地主要转化为建设用地、林地及水域,建设用地面积增幅为304.90%,2015年达到932.55 km2。(2)重庆市主城区枯水期、平水期、丰水期径流深度呈上升趋势,径流深度分别为0～14.58 mm,12.70～93.74 mm,62.45～184.85 mm。(3)重庆市主城区各土地利用类型产流能力呈林地<草地<耕地<未利用土地<建设用地<水域的趋势; 径流系数增加区域主要分布于“两江四山”间较平坦地区,呈南北延伸趋势; 地表径流与建设用地的PLAND,LPI,COHESION,AI呈极显著正相关性,与DIVISION,NP呈极显著负相关性。说明在快速城市化进程中,可通过合理规划土地利用景观格局,优化土地利用结构及空间分布以控制地表径流。
In order to analyze the influence of land use change on surface runoff in the main urban area of Chongqing, based on the SCS hydrology model, the related data such as land use, rainfall, and soil type were selected to simulate the surface runoff during dry, normal, and wet periods under normal soil moisture(AMC Ⅱ)in the early stage. The impact of land use change on surface runoff was analyzed according to the runoff yield capacity, runoff coefficient, and landscape pattern of various land use types. The results showed that:(1)from 2000 to 2015, the land use types in the main urban area of Chongqing City were mainly cultivated land and forestland, and the proportion of these types continued to decline; the cultivated land was mainly transformed into construction land, forestland, and water area, and the construction land area increased by 304.90% and reached 932.55 km2 in 2015;(2)the runoff depths in the main urban area of Chongqing City were increasing during the dry, normal, and wet period in which the runoff depths were 0～14.58 mm, 12.70～93.74 mm, 62.45～184.85 mm, respectively;(3)the runoff generation capacity of various land use types in the main urban area of Chongqing City increased in the order: woodland<grassland<cultivated land<unused land<construction land<water area; the areas with increased runoff coefficient mainly distributed in the relatively flat areas between the ‘two rivers and four mountains', showing a north-south extension trend; surface runoff had a very significant positive correlation with PLAND, LPI, COHESION, AI of construction land, and a very significant negative correlation with DIVISION and NP, indicating that in the process of rapid urbanization, land use landscape pattern could be rationally planned, and land use structure and spatial distribution could be optimized to control surface runoff.