天津市不同功能区土壤物理特性研究

目的]对天津市常用绿化土壤的基本性质以及渗透性能进行研究,为天津市下凹式绿地的设计及推广应用提供理论依据。方法]选取天津市不同功能区不同植被类型(草坪、灌木)的土壤,对土壤的颗粒组成、容重、孔隙度以及渗透系数进行研究,并分析天津土壤性质间的相关性。结果]天津市除老居民生活区属于粉土外,其他功能区均属于粉质黏土。受人为扰动影响,各功能区绿化土壤容重大,孔隙度较低,土壤压实严重,其中土壤容重为1.34~1.55g/cm~3,土壤孔隙度为42.50%~52.80%;各功能区的渗透系数差异很大,范围为8.8E-06~1.3E-03cm/s,大小趋势主要受人为因素的影响,表现为:文教区居民生活区工业区郊区林带公园区道路交通区;植被类型对土壤渗透系数有影响,为草坪灌木。土壤的渗透系数与土壤含水率、土壤容重呈负相关性,与土壤孔隙度呈正相关性;土壤容重与土壤孔隙度呈极显著负相关。结论]天津地区土壤压实严重,草坪与灌木土壤以弱透水和中等透水为主。

Physical Properties of Soil from Different Functional Areas in Tianjin City

Objective] Studying the characteristics and permeability of commonly used green soil in Tianjin City, in order to provide theoretical basis for the design and promotion with application of low elevation greenbelt in Tianjin City.Methods] Different functional areas and different vegetation types(lawn, shrubs) of soil were selected to study soil particle composition, bulk density, porosity and permeability coefficient and to analyze the correlation among soil properties.Results] The functional areas belonged to silty clay except for the old residential with silty soil. Affected by artificial disturbance, the green soil had greater bulk density, low porosity and severe soil compation. Soil bulk density was 1.34~1.55 g/cm³, soil porosity was 42.50%~52.80%. There were significant differences in permeability coefficient of each functional area, the range was 8.8E-06~1.3E-03 cm/s, the size trend was mainly influenced by artificial factors, ranked as follows:cultural and educational zone > residential zone > industrial zone > suburban forest zone > park zone > traffic zone; Vegetation type had an influence on soil permeability coefficient. The permeability coefficient of soil was negatively correlated with soil moisture content and soil bulk density, positive correlation with soil porosity. Soil bulk density was significantly negatively correlated with soil porosity.Conclusion] The soil compaction is serious in Tianjin City, the lawn and shrub of soil is dominated by weak permeable water and medium permeable water.