西北旱区压砂地土壤水分入渗规律研究

A Study on Soil Water Infiltration of Gravel-mulched Field in Northwestern Arid Area

基于野外大田试验,用灰色关联分析法和土壤水分入渗模型研究了裸地（CK）及不同种植年限压砂地土壤水分入渗规律。结果表明,土壤水分入渗能力依次为：新砂地〉中砂地〉老砂地〉裸地（CK）,入渗初期新砂地入渗能力明显高于中、老砂地及裸地,压砂地入渗速率新砂地最高,中砂地、老砂地次之。裸地土壤水分入渗过程呈指数负相关,压砂地土壤水分入渗均呈幂函数负相关,土壤累积入渗量随着时间的推移呈幂函数正相关,相关系数介于0.976~0.996,Horton模型与Kostiakov模型均可描述压砂地土壤水分入渗规律,可以代表压砂地土壤水分入渗模型。根据灰关联度的大小,土壤水分入渗能力依次为：新砂地（1.000）〉中砂地（0.756）〉老砂地（0.729）〉裸地（0.622）。

Based on the wild field experiment, this research investigated soil water infiltration process by grey relational grade analysis in bare land（CK） and gravel-mulched field of different planting years. Results showed that soil water infiltration capacity decreased as follow： new gravel-mulched field（NGM） 〉 medium gravel-mulched field（MGM） 〉 old gravel-mulched field（OGM） 〉 bare land（CK）. At the beginning, infiltration capacity of NGM was significantly higher than that of MGM, OGM, CK. Infiltration rate was the highest in NGM, then in MGM and in OGM.The process of soil water infiltration in CK presented index negative correlation and gravel-mulched field presented power function negative correlation. Soil cumulative infiltration volume had power function positive correlation with time, the correlation coefficient between 0.9764 and 0.9960. Both Horton infiltration model and Kostiakov infiltration model could describe soil water infiltration patterns. Based on grey relational grade,soil water infiltration capacity was：NGM（1.000） 〉 MGM（0.756） 〉 OGM（0.729） 〉 CK（0.622）.