基于容量交易方法的海绵城市最优规划尺度分析

Capacity trading approach-based analysis on optimal planning scale of sponge city

容量交易方法能够利用不同功能区径流削减潜力的差别,提高片区径流处理能力。为了探讨容量交易方法在不同地区的应用效果并确定适宜的交易尺度,选取天津、南京和扬州的部分区域为研究对象(研究区1、2、3),利用ArcGIS人工解析土地利用,并划定不同尺度范围的交易区,分析尺度对交易效果的影响。结果表明:(1)80~180 hm^(2)左右的空间范围(大约包括20~35个功能区)是适合不同研究区进行容量交易的最佳尺度,该尺度反映了海绵城市的最优规划范围。相对而言,单个功能区面积较小、分布较均匀的地区(研究区2和3)可以在较小的尺度达到最佳交易效果(75%),而单个功能区面积较大、分布不均匀的地区(研究区1)需要更大的尺度才能达到同样效果。(2)容量接收区和贡献区的交错间隔分布有利于交易的进行,而这种有利的分布形式在超过最佳尺度范围后逐渐消失。容量交易方法可以合理配置地表径流,赋予功能区更多灵活性,确定与海绵城市规划相匹配的最佳尺度,为推进海绵城市建设提供参考。

The capacity trading approach can enhance the areal runoff treatment capacity with the difference among the runoff reduction potentials of various functional zones. In order to explore the application effect of the capacity trading approach in different areas and determine the appropriate trading scale, parts of the areas of Tianjin, Nanjing and Yangzhou are taken as the study objects(study areas 1.2.3) herein, and then the influence of scale on the trading effect is analyzed by means of manually analyzing the land-use with ArcGIS and delimiting the different scale ranges of the capacity trading zones. The results show that(1) the spatial range of about 80~180 hm^(2), which reflects the optimal planning range of sponge city, is the optimal scale for the capacity trading in different study areas. Relatively speaking, the optimal trading effect(75%) can be achieved at a smaller scale in the areas with smaller area and uniform distribution of functional zone(study areas 2.3), while the same effect can only be achieved with more larger scale for the areas with larger area and non-uniform distribution of functional zone(study area 1);(2) the staggered interval distribution of capacity receiving zone and contribution zone is favorable to the capacity trading, but this favorable distribution pattern is to be gradually disappeared after exceeding the optimal scale range. The capacity trading approach can reasonably allocate surface runoff, give more flexibility to the functional zone, determine the best scale to match the sponge city planning scale and then provide the related references for promoting the construction of sponge city.