采用大田棉花滴灌栽培方式,设置了3种可降解地膜(BMF1、BMF2、BMF3)、塑膜(MF)、裸地(CK)5个处理,探讨可降解地膜的降解性能及对土壤水分、温度和棉花生长的影响.结果表明,可降解地膜在棉花生长前期保持良好的完整性,播种后第50天至第70天开始出现降解,降解速率、降解强度均表现为BMF2>BMF3>BMF1,BMF2、BMF3处理在播种后第180天分别达降解5级水平,地膜质量损失率达51.38%、45.62%,可降解地膜覆盖可提高土壤温度,较CK处理5、10、15、20 cm增温5.2%~9.9%、4.8%~9.6%、4.0%~8.5%、3.2%~7.2%;保持土壤含水率,较CK处理平均增湿0.60%~0.13%;显著促进滴灌棉花前期生长,且增产效果显著,BMF2处理籽棉产量5262 kg/hm2,较CK增产13.21%.研究认为,可降解地膜增产效果低于普通塑料地膜,但是能够自然降解,既减少残膜回收工序,又对土壤环境无不良影响.%In this project,five kinds of treatments by drip irrigation in cotton field were set:biodegradable plastic film (BMF1,BMF2 and BMF3),plastic film (MF)and bare soil drip irrigation (CK),and their effects of degradable plastic film on soil moisture,temperature and cotton growth were discussed.The re-sults showed that good integrity of degradable plastic film in the early stage of cotton growth was kept;Degradation began from the 50th to the 70th day after sowing.The degradation rate and intensity of degra-dation were as follows:BMF2>BMF3>BMF1 .The degradation level of BMF2 and BMF3 reached the level of grade 5 on the 180th day after seeding,respectively and their film quality loss rates reached 51.38% and 45.62%.Degradable mulching could raise soil temperature .Compared with CK 5 cm ,10 cm ,15 cm and 20 cm,temperatures were raised by 5.2%-9.9%,4.8%-9.6%,4.0%-8.5% and 3.2%-7.2%;The water content of the soil was kept,0.60%-0.13% higher than that of the CK.The early growth of drip irrigation cotton was significantly promoted,and the effect of increasing yield was remarkable.The yield of seed cot-ton treated with BMF2 was 5262 kg/hm2 ,13.21% higher than that of the CK.Studies suggested that the yield increase of degradable plastic film was lower than that of ordinary plastic film,but it could degrade naturally,which reduced the recovery process of residual film.
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