天津市不同种植年限蔬菜地土壤水分特征影响因素及其演变

Influential factors of moisture characteristics and its changes for vegetable soil with different planting years in Tianjin City

通过对不同种植年限蔬菜地土壤饱和含水量、田间持水量、萎蔫含水量和有效含水量的分析,研究了土壤水分特征的主要影响因素及其演变趋势。结果表明,种植5 a以上1、0 a以上及15 a以上蔬菜地土壤饱和含水量的主要影响因素分别为团聚体、有机质含量、容重及pH值;田间持水量的主要影响因素分别为团聚体含量、结构系数和pH值;有效水含量主要影响因素分别为团聚体含量、结构系数及团聚体含量;萎蔫含水量影响因素不明显。随着种植年限的延长,研究区土壤饱和含水量以及田间持水量呈下降趋势,土壤持水性能、土壤水分供释及利用能力下降。

Influential factors of moisture characteristics, including saturation water content, field capacity, wilting moisture and available water content, and its changes for vegetable soil with different planting years in Tianjin were analyzed. The results showed that saturation water content of vegetable soil with different planting years（over 5 a, over 10 a and over 15 a） were affected by aggregates contents, soil bulk densities and pH values respectively. Field capacities of them were affected by aggregates contents, structure coefficients and pH values respectively. Available water contents of them were affected by aggregates contents, structure coefficients and aggregates contents. However, influential factors of wilting moisture were not obvious. And as the increasing of vegetable planting years, soil saturation water content and field capacity were ＇reducing. Thus, water holding and supplying abilities of soil were reducing. It needed improving water adsorption and using ability of vegetable soil, especially with longer planting years. These results can provide references for water holding and reasonable using of soil with different planting years in arid areas such as Tianjin.