Improvement of Rainwater Infiltration Property and Its Effect on the Corresponding Storage Capacity of Soil in Urban Green Space

Lou Keke,Kang Aihong,Lu Zhiping,Yin Chengsheng,Wu Zhengguang,Xu Xueling,C.-H Weng,R Weerasinghe

doi:10.1051/e3sconf/20185304044

Abstract

Urban green space whose soil permeability is the main factor affecting hydrological cycle plays a very important role in promoting rainwater infiltration, replenishing groundwater and reducing peak flow. In order to enhance the storage and infiltration ability of soil, different types and contents of conditioner are added to study the laws of the changes in permeability of various soils. The results showed that straw and sawdust can effectively increase the permeability coefficient of soil. According to the comparison under the same conditions, the improvement effects of straw is slightly better than sawdust, but no order of magnitude difference. The sandy soil reformed by 3.6% Straw or 4.2% Sawdust and the loam reformed by 29.5% Straw or 30.2% Sawdust can meet infiltration requires of rainwater whose rainstorm recurrence period is 10 years. The clay is not suitable for urban green space soils with higher rainwater storage and infiltration requirements. The reformed green space can effectively reduce the runoff peak flow and delay the generated time of the runoff. The higher the content of the modifier, the more obvious the advantage of promoting the hydrological cycle and reducing the runoff.

Highlights

As a natural rainwater storage and purification facility, urban green space helps enhance the infiltration of runoff to supplements the groundwater[1,2,3], and reduces the speed of runoff
It can be seen that the infiltration rate of the urban green space soil in China is generally low, which is mainly due to the low permeability coefficient
The loam reformed by 23.5% straw or 24.1% sawdust can meet infiltration requires of rainwater whose rainstorm recurrence period is 3 years

Summary

Introduction

As a natural rainwater storage and purification facility, urban green space helps enhance the infiltration of runoff to supplements the groundwater[1,2,3], and reduces the speed of runoff. The function of urban green space to promote runoff circulation is achieved through soil infiltration In cities such as Shanghai and Guangzhou, and even in some cities where there is not sufficient runoff, flooding caused by the ponding after heavy rain occurred. This is due to the fact that the design of the municipal drainage network is lagging behind, and has something to do with that the urban green space have not really played a role in enhancing the infiltration of runoff. It is very meaningful to use local conditioner to enhance the storage of runoff in urban green space

Methods

Results

Conclusion