宁夏环香山地区压砂地土壤水分特征曲线及入渗速率的特征分析

Analysis of Soil Water Characteristic Curve and Infiltration Rates of Gravel-mulched Land around Xiangshan Mountain Area in Ningxia

以宁夏压砂地退化过程中土壤水分变化规律为研究对象,开展了不同压砂年限下土壤水分特征曲线、土壤入渗速率的测定,研究结果表明:农田压砂初期土壤贮水能力很强,当压砂10 a后土壤贮水能力逐年下降,土壤水状况以及水分利用效率也逐步降低。压砂初期在较低吸力时(1 bar以下)即可获得较多的有效水量,但随着利用年限的增加,农田压砂逐步失去保水能力。压砂初期明显提高了土壤的入渗速率,随着压砂年限的增加土壤入渗速率逐步降低,压砂10年土壤入渗速率低于农田ck,压砂15 a时土壤初入渗速率比农田CK下降了63.37%。综合分析说明,压砂初期,土壤的水势较高,吸力较小,作物吸收容易,但随着压砂年限的增加,土壤水势逐步下降,吸力增加,导致作物利用逐渐困难。

In this paper, soil moisture changes of gravel-mulched land degradation were taken as the object of study. The results showed that the gravel-mulched land could obviously improve the soil water status, but with gravel-mulched land cultivation age increased, and soil moisture tended gradually to be in bad condition in 40 year gravel-mulched land. Sandy land had lost water holding capability. Gravel-mulched land initial soil water storage ability was very strong, and soil water storage capacity had decreased year by year after 10 years mulching. Soil water and water use efficiency also gradually reduced. Gravel-mulched land initial markedly increased soil infiltration rate, with the ages increased, soil infiltration rate decreased gradually. Gravel-mulched land with 10 years soil infiltration rate was lower than that of farmland CK. The initial soil infiltration rate fell 63.37% in gravel-mulched land with 15 years than farmland CK.