干化土壤连续多年覆膜后水热盐分布特征研究.

In order to reveal the annual variation of the distribution of water, heat and salt in the dry soil in the gullied rolling loess area after continuous mulching for many years and provide reference for further research on improving the water, heat and salt status of dry layer soil, the paper took jujube woodland that covering with the white film (colorless transparent plastic film), black film (black bovine felt) and bared ground control test plots continuously for 5 years in Mizhi County, Northern Shaanxi Province as the research object, the paper analyzed the migration and changes of water, temperature and salt in different soil layers during the year based on the location monitoring data of soil water content, temperature and conductivity by GS3 sensors with buried depths of 5, 15, 30, 50, 75, 100, 125 and 150 cm. The results show that a) after continuous film mulching for 5 years, the water content of 0-150 cm soil layer is significantly higher than that of bared soil, especially the water storage of 0-60 cm soil layer is significantly increased, and the black film mulching has a better effect on rain collection and water conservation than that of the white film mulching. b) The soil temperature in each soil layer of the two mulching plots is significantly higher than that of the bared plots. The white film mulching has a better thermal insulation effect in the cold period, and the black film mulching has a certain regulatory effect on the soil temperature in the 0-60 cm tilling layer in the high temperature period. c) After many years of film mulching, the phenomenon of surface soil salt accumulation will occur, but it will not cause soil secondary salinization. d) There is a significant positive correlation between soil water and salt in each plot at different stages, and the correlation between water and salt is relatively weaker in the plot covered with black film, while the correlation between soil water and heat and salt is significantly different. The two kinds of film mulch have different regulatory effects on soil water, heat and salt at different stages. [ABSTRACT FROM AUTHOR]