上海中心城区百年河流水系变化及影响因素分析

Base the data of disappeared rivers from 1860 to 2003 in center district of Shanghai, the variation of river system and its environmental impact were analyzed. The research results showed that (1) Over 260 rivers, in length about 470 km were disappeared in center district of Shanghai during the past 140 years. The area of water area and water surface ratio reduced 9.42km2 and 3.25 per cent, respectively. The structure of river system was destroyed greatly. High-urbanization lessened the branching ratio, which leaded to an abnormal fractal dimension. (2) The rivers in the center district centralized disappeared during several phases. The dominating river vanished reasons were altered in different three times. From 1860 to 1949, the dominating reasons included roads build, natural oblivion, concession expansion and residence zone build. From 1949 to 2003, those were city planning construct and residence zone build. (3) At a rough estimate, from 1860 to 2003, the substantive disappeared rivers caused the total river storage capacity and per area river storage capacity reduce about 1,884×104m3 and 4.56×104m3/km2, respectively. Now, the total river storage capacity reduced near 80 per cent compare with that of 140 years ago, so the ability of storage capacity was greatly weakened in the center district of Shanghai. The number of cumulative built municipal pumping stations significant positively related with cumulative number, cumulative length and cumulative storage capacity of disappeared rivers from 1950s to 1990s.