Taking the typical parks and public green belts in the central urban area of Shanghai for examples, water reservoir storage of soils of different types and influencing factors were investigated based on field surveys. The results showed that the total reservoir capacity of soils of the green belts in the central urban area of Shanghai was relatively low. However, the whole green belts still accumulated a large amount of water, which reached up to 1.88×107 m3. The existing water volume was 75.7% of the total reservoir capacity, while the remaining water storage was relatively low. The detention capacity and the effective storage of green belts were 31.6% and 27.2%, respectively. The dead storage was 44.5 %. Moreover, some difference existed in the water reservoirs for different vegetation types. The total water reservoir capacity of soils and the remaining water-storage space of the tree and brush lands were obviously higher than those of the grass lands. The water-detention capacity and the effective storage of the brush lands were remarkably higher than those of the tree and grass lands, but there was no remarkable difference among various vegetation types for both the existing water volume and the dead water storage. Thus, reducing soil compaction, increasing organic-matter content, improving physical properties and optimizing plant allocation of green belts would improve the water reservoir capacity effectively for the urban green belt soils.
以上海中心城区典型公园和公共绿地土壤为研究对象,通过实地调查,分析上海中心城区绿地土壤水库库容、常数特征及影响因子.结果表明: 上海中心城区绿地土壤总库容偏低,但就整个中心城区绿地,土壤蓄积水量可观,达1.88×107 m3;土壤水分现存量较高,占总库容的75.7%,土壤剩余蓄水空间偏低;绿地土壤滞洪库容和有效库容分别占土壤总库容的31.6%和27.2%;而土壤死库容占总库容的44.5%.不同植被类型土壤水库存在差异:其中,乔木和灌木地土壤总库容、剩余蓄水空间均显著高于草地;灌木地土壤滞洪库容、有效库容均显著高于乔木地、草地;但各植被类型土壤水分现存量、死库容差异不显著.建议通过降低土壤压实、增加土壤有机质含量、改善土壤物理性质和优化绿地植物配置来提高城市绿地土壤水库库容.
Keywords: Shanghai; central urban area; green belt; soil; vegetation type; water reservoir.