上海宝山快速城市化进程对河网演变影响分析

以我国快速城市化区域——上海宝山区为例,基于近20 a经济发展和河系水网变化相关数据,探讨区域河网水系的时空变化规律,不同功能区的河网变化分异特征及其驱动因子。分析结果表明:(1)宝山区的河网水系数量变化经历了基本稳定(1994-2003年)、快速消亡(2003-2006年)、缓慢回升(2006-2008年)3个阶段,这与其城市化发展进程有较好的对应关系;(2)不同功能区域河网数量和水环境质量变化具有分异性,其中水面率大小关系为Ⅲ区>Ⅰ区>Ⅱ区,有机污染综合指数和总磷为Ⅱ区7Ⅰ区7Ⅲ区;(3)不同功能区的河网水系数量和水环境质量对城市化响应具有明显差异,居住用地、工业用地和设施用地的增加是各功能区河网水系变化的主要驱动因素。在此基础上,对于区域防洪除涝问题提出建议,即在城市化进程中,不仅应重视河道数量,更应重视河道长宽度的保护,才能改善河网水质和水生态环境。

Influence Analysis on River Network under Rapid Urbanization:A Case Study of Baoshan Area,Shanghai

Baoshan District in Shanghai is taken as study area.Based on related data of economic development and river network changes spanning nearly 20 years,analysis on the tendency and spatial differential features of river network based on multi-temporal and multi-spatial scale was made while the impact of every type of land use changes driven by urbanization was further studied.Results showed that river network has experienced three changing phases including trunk rivers manmade modifying and decline of branch river(1994-2003),sharp reducing of tributary(2003-2006) and slow recovery(2006- 2008),which was in correspondence with its urbanization development level.River network and quality of water changes in different urban functional areas had a significant difference.Driving factor analysis showed that quality and quantity of river network responded to the urbanization differently.Changes of residential land,industrial land and facility land were major driving forces causing the changes of river network respectively.The measures to avoid the flood and waterlogging disaster were also discussed,the change of river length and width should be attached much importance as well as the number so as to improve urban water quality and water environment.