校园绿地不同乔木林雨后土壤含水率差异性研究

Differences in Rainwater Retention of Different Forest Soils in Campus Green Lands

在目前建设海绵城市的背景下,城市人工绿地建设也是整体规划的重点。主要针对集雨绿地设计中乔木林地的植物种类选择进行探讨,对校园绿地中不同乔木林雨后土壤含水量进行测量,通过比较分析发现,疏林中集雨优势银杏(Ginkgo biloba)林>楸树(Catalpa bungei)林>玉兰(Magnolia denudata)林;枇杷(Eriobotryajaponica)林、梅(Armeniaca mume)林>木槿(Hibiscus syriacus)林、石榴(Punica granatum)林、碧桃(Amygdalus persica)林;密林中榉树(Zelkova serrata)林、棕榈(Trachycarpus fortunei)林>国槐(Sophora japonica)林。疏林比密林能蓄集更多的雨水,这跟以往的研究相同。在疏林有地被绿地中,银杏、楸树这类枝条与树冠轴夹角为锐角,叶片较稀疏的乔木类型表现出较强的蓄滞雨水能力;小乔木林整体比大乔木林表现稳定。建议集雨绿地乔木林应设计为疏林+地被的形式,并采用树冠较小,树形较紧凑的树种。

On the background of constructing sponge city,the construction of city artificial green spaces is one of the important issues to overall planning. Selections of appropriate tree species in the design of water harvesting green spaces were investigated by measuring the moisture contents of the soils of different tree species plantations in university campus after raining. The results of data comparison indicated that the ca- pacities of water collection of different open plantations were in the orders of Ginkgo biloba ~ Catalpa bungei~ Magnolia denudata. Eriobotrya japonica, Armeniaca mume Hibiscus syriacus , Punica grana- turn ,Amygdalus persica. For dense arbor plantations, the order was Zelkova serrata, Trachycarpus fortu- neis^Sophora japonica. Open plantations could accumulate more rainwater than dense ones,which was in accordance with the previous studies. Among the open plantations, G. biloba and C. bungei demonstrated strong ability in retaining rain water due to the acute angles between the branches and the canopy axel. The ability of rain collection for small-scale plantations was more stable than that of large-scale ones. It was suggested that the rainwater retention design should adopt the form of open plantation covered with ground vegetation,and the plant species was those with small and dense crown.