【摘要】 以重庆市为代表的南方山地丘陵城市建设造成的弃土坡 ,年土壤侵蚀模数达 10万t/km2 以上 ,比裸露荒地年侵蚀模数大 9～ 11倍 ,丰水年可达 30万t/km2 以上。城市化把地面大面积变成不透水层 ,使径流系数增大 ,汇流时间缩短 ,洪水总量与洪峰流量增大 ,城市河流洪水灾害的发生频率增大。建议在城市建设规划时注意对原有水域的保护利用 ,加强城市水文特征及水土流失规律的研究 ,严格按水土保持法的规定编报开发建设项目水土保持方案并切实组织实施更多还原

【Abstract】 The annual soil erosion modulus of spoil slopes created by city construction that is situated in a hilly region of south China, taking Chongqing Municipality as a representative is as high as to 100 000 ton/km 2, 11 times higher than that of the uncovered wasteland and that can reach to 300 000 ton/km 2 during a wet year. The urbanization has turned the ground surface into an impermeable layer in a large area, increased runoff coefficient, shortened the concentration time, increased the total volume of flood water and peak discharge of floods and increased the frequency of floods of city rivers. Thus, it suggests to pay attention to the protection and utilization of existing water areas in a city planning, strengthen the study on hydrologic nature and law of soil and water loss, work out a soil and water conservation plan of a development and construction project strictly according to the stipulations of Soil and Water Conservation Act and implement it earnestly.更多还原