城市扩展过程对湿地影响的情景模拟研究——以河北怀来为例

在复杂多变的环境下,情景模拟法因其能考虑突发干扰的影响并能聚焦长期规划而表现出突出的优势。怀来是北京重要的水源地和环境保护屏障,2022年北京-张家口冬奥会的筹办将可能加快怀来的经济发展和城市扩展,进而对湿地的空间压力产生重要影响。因此,论文利用情景模拟法,结合城市扩展模型（land use scenario dynamics-urban,LUSD-urban）和湿地空间压力模型,模拟了趋势外推、城市规划和冬奥会3种情景下怀来未来城市扩展对湿地的空间压力。结果显示城市扩展导致怀来湿地空间压力增大,湿地平均压力从2000年的0.399增加到2013年的0.439,增长了10.03%。同时,湿地空间压力高于0.5的像元比例从6.73%增加到17.42%。3种情景下,2013—2030年怀来的湿地空间压力将增长0.002~0.005。冬奥会的举办将为怀来湿地带来更大的空间压力,冬奥会情景下湿地压力的热点区面积最大,为83.74 km²,是3种情景下共有热点区面积的1.44倍,新保安镇、土木镇和沙城镇的非城市用地面临的空间压力较大。因此,怀来县在未来制定城市规划时应充分考虑县内湿地生态系统,在保护湿地资源的基础上有效促进经济的发展。

Scenarios Simulation of the Spatial Stress on Wetlands by Urban Expansion: A Case Study of Huailai County

Scenario simulation has shown prominent advantages in complex human-environment systems, for it considers the impacts of unexpected disturbance and focuses on long-term plans. The 2022 Beijing & Zhangjiakou Winter Olympics might accelerate economic development and urban expansion in Huailai, which would lead to a significant impact on the spatial stress of wetlands in this area. This paper adopted the scenario simulation method as well as LUSD-urban (Land Use Scenario Dynamics-urban) model and a spatial stress model to simulate the spatial stress on wetlands by urban expansion in Huailai in 2030. We designed three scenarios, i.e., the business-as-usual scenario, the urban planning scenario and the Winter Olympic scenario, and compared the results under the three scenarios. The results showed that the spatial stress on wetlands by urban expansion has increased by 10.03%, from 0.399 in 2000 to 0.439 in 2013. Meanwhile, the proportion of land with a spatial stress greater than 0.5 increased from 6.73% to 17.42%. The spatial stress on wetlands during 2013-2030 will increase by 0.002-0.005 under the three scenarios. The Winter Olympic scenario will witness the largest increase in spatial stress on wetlands. The hotspot area of spatial stress on wetlands will be 83.74 km² under the Winter Olympic scenario, 1.44 times as large as the common hotspot area under the three scenarios. The non-urban land in the towns of Xinbao’an, Tumu and Shacheng will face high spatial stress. Thus, the future urban planning of Huailai County should take full account of the importance of wetland ecosystems, so as to protect the scarce wetland resources, improve the water quality in the Guanting Reservoir and promote economic development on the basis of an effective environmental protection.