环杭州湾城市规划及产业发展对湿地保护的影响

根据浙江省环杭州湾产业带2005年TM影像和2005-2020年城市规划数据．利用GIS空间分析方法，分析了规划期间建设用地扩展对湿地的侵占威胁．并对湿地退缩的潜在风险进行分析。结果表明：①环杭州湾产业带湿地资源丰富，类型多样，分布广泛。现状建设用地在空间上与湿地交错分布，关系十分密切。②未来15年，城市建设用地扩展规模大、速度快，将侵占大面积湿地，主要是分布在杭州湾南岸湿地围垦区的坑塘、养殖水面类湿地：宁波、杭州、慈溪是湿地退缩最严重的区域。⑧由于现状建设用地与湿地空间分布紧密相关，湿地被建设用地侵占的潜在风险整体上较大．且随着建设用地的扩展．对湿地的侵占有加剧的趋势。④建设用地增长幅度及其规划布局对湿地减少有重要影响．应通过调整建设用地规划、湿地占用补偿、城市湿地公园建设等措施．加强湿地保护。

Impact of Urban Planning and Industrial Development on Wetlands in Hangzhou Bay

Hangzhou Bay Industries Belt is located in the north of Zhejiang Province, which is the important part of the Yangtze River Delta.With the rapid development of urbanization and industrialization, plenty of wetlands in this area were occupied and the conflict between economic development and wetlands protection will still be severe in the future.Based on remote sensing images and urban planning data, this paper analyzed the planned conversion of wetlands to urban construction lands from 2005 to 2020 and the potential risk to wetlands using GIS spatial model.Conclusions were drawn as follows:(1) Wetlands in Hangzhou Bay Industries Belt are distributed widely and most of them are close to present urban construction lands.(2) According to present planning, construction lands will expand rapidly in the coming 15 years and will occupy many wetland areas, most of which are distributed in Ningbo, Hangzhou and Cixi.Two wetland types, i.e., ponds and aquiculture water, which are distributed in the reclaimed areas of Hangzhou Bay south coast will decrease greatly.Potential risk to wetlands by construction lands layout is great at Daishan and Zhoushan.(3) On the whole, the potential risk to wetlands is great.The first risk rank is about 8000 hm2, being 69% of the total decreased area.The second, third and fourth risk ranks are about 2000 hm2, 700 hm2 and 700 hm2, accounting for 19%, 6% and 6% of the total decreased area, respectively.Besides, the tendency of wetlands occupation by urban construction lands will not decrease from 2005 to 2020.(4) The increase extent and the layout of construction lands have great effect on the decrease of wetlands.Adjustment of construction lands planning, compensating for wetlands loss, building of wetland park and other measures should be taken to protect wetlands.