不同类型地膜覆盖对土壤水热与葵花生长的影响

Effects of Different Degradable Films Mulching on Soil Water Potential,Temperature and Sunflower Growth

通过设置普通塑料地膜、A型生物地膜、B型生物地膜、液体地膜以及无膜覆盖（CK）5个处理,比较分析不同类型地膜覆盖对土壤地温、土壤基质势以及葵花生长和产量的影响。结果表明,葵花生育前期（6—7月）普通塑料地膜和生物地膜覆盖的地温无显著差异,而在生育后期特别是9月份普通塑料地膜处理的土壤表层（0～20 cm）地温明显高于生物地膜覆盖处理,其中A型生物地膜覆盖处理的地温略高于B型生物地膜覆盖处理,而液体地膜覆盖与无膜处理在全生育期地温显著低于普通塑料地膜和生物地膜覆盖处理（p〈0.05）。生物地膜覆盖处理的保水效应与普通塑料地膜覆盖处理相近,仅在作物生长末期（9月底）生物地膜与普通塑料地膜覆盖处理在0～20 cm土层基质势差异达到显著水平,尽管液体地膜覆盖与无膜处理相比有一定的保水效应,但差异不显著。生物地膜覆盖下葵花株高、叶面积指数以及收获后的叶质量、茎质量、花盘质量和产量与普通塑料地膜覆盖处理均无显著差异,但都显著优于液体地膜覆盖和无膜处理（p〈0.05）。

With the large application of agricultural plastic film, the residual of plastic film was continuously increased in soil during the last few decades. The application of biodegradable film could solve the environmental pollution because of its totally degradable property. Agricultural film was specially required in arid and cold region, so it was very important to study and get the suitable degradable film for sustainable agricultural development. Five treatments including plastic film, biodegradable film （thickness 0. 012 mm）, biodegradable film （thickness 0. 008 mm）, liquid film and no film （CK） were used to compare the effects of different types of film on soil temperature, soil water potential, crop growth and yield. The results showed that there were no significant differences between plastic film and biodegradable film treatments during early crop growing period （June and July） , whereas the soil temperature in 0 ～20 cm soil layer for the treatments of biodegradable film was a little lower than plastic film treatment because of film＇ s degradation, especially for the treatment of biodegradable film of thickness 0. 008 mm during the end of crop growth. However, the soil temperatures of liquid film and no film treatments were obviously lower than plastic film treatment. The results for soil water potential among different treatments were similar, and it was very close between plastic film and biodegradable film treatments, but the maximum soil water potential was shown in 0 ～ 20 cm soil layer during the end of September, and there was significant difference between plastic film and biodegradable film treatments （p 〈 0.05）. No significant differences were found between plastic film and biodegradable film treatments for the crop height, leaf area index （LAI） , dry matter of leaf, stem, flower dish and yield. However, both of these two treatments were clearly better than liquid film and no film treatments. Thus, it was feasible to replace plastic film with biodegradable film for mulching in arid and cold region.