液体地膜对黄土丘陵沟壑区侧柏林土壤性质影响

Effects of liquid film mulching on soil properties of Platycladus orientalis stand in the hilly-gully region of Loess Plateau,western China

干旱缺水是影响黄土丘陵沟壑区植被恢复的主要因素。在黄土丘陵沟壑区侧柏林地喷施液体地膜,采用随机区组设计,通过分析处理与对照的试验数据,研究液体地膜对侧柏林土壤水分及养分的影响,解决在植被恢复过程中缺水少肥的状况。结果表明：1）喷施液体地膜后初次测量0-10、〉10-20、〉20-40、〉40-60 cm土层的土壤含水量降低量处理比对照少0.26%、0.04%、0.08%、0.05%;降水后再次测量发现各土层土壤含水量降低量处理比对照少1.35%、1.28%、0.52%、0.23%;2）液体地膜降解后能有效增加土壤表层有机碳、全氮的质量分数,0-10 cm土层的土壤全氮质量分数处理比对照高0.11 g/kg,土壤有机碳质量分数处理比对照高4.27 g/kg;3）试验期间8—9月、9—10月侧柏树高平均增量处理分别为对照的231%、224%;8—9月、9—10月地径平均增量处理分别为对照的305%、261%。建议在黄土高原地区造林时合理使用液体地膜。

Water shortage is the main factor influencing vegetation restoration in the hilly and gully region of Loess Plateau of western China. Understanding the effect of spraying liquid film in the Platycladus orientalis forest land on soil moisture and nutrient status would help us solve the problem of water and nutrition deficiencies in the course of vegetation restoration. The results showed that： 1） In the first measurement after spraying liquid film,the amounts of decrease in the soil moisture content in the 〉0-10 cm, 〉10-20 cm, 〉20-40 cm, 〉40-60 cm soil layers were 0. 26%,0. 04%,0. 08% and 0. 05%less than that in control. Measurement after rain found that the decrease in soil moisture content of each soil layer was 1. 35%,1. 28%,0. 52% and 0. 23% less compared to the control,respectively. 2）Liquid film after decomposition can effectively increase the contents of soil organic carbon（ SOC） and total N. Soil total N content was 0. 11 g / kg higher and SOC content was 4. 27 g / kg higher than the control in 0-10 cm layer. 3） After treatment,the average increment of the height of P. orientalis was 231%from August to September and 224% from September to October,compared to the control,and the average increment of diameter was 305% and 261% during the corresponding periods. Our study suggeststhat the liquid film should be applied in the loess plateau region.