不同膜下滴灌模式对土壤水分及棉花产量的影响

采用负压计法和烘干法,监测不同的灌溉定额、灌溉频率下膜下滴灌棉田在水平和垂直方向的水分含量,并调查棉花生长状况。结果表明,当灌溉水质为淡水且滴孔流量为1.6L·h^-1时,过量灌溉（450mm）和适量灌溉（375mm）膜内0～60cm土层的含水量适宜,过量灌溉的含水量最高,少量灌溉（300mm）使土层在蕾期以后处于轻度干旱状态;低频（10d）和适频（7d）灌溉膜内0～60cm土层的含水量适宜,低频灌溉的含水量最高,而高频（3d）灌溉使土层在花铃期处于轻度干旱状态;灌溉定额和灌溉频率对棉花产量均有显著影响,过量和高频灌溉的棉花产量分别为区组内最高。

Study on Effects of Different Mulched Drip Irrigation Modes on Soil Moisture and Cotton Yield

Tension meters and oven drying method were adopted to monitor the soil moisture contents at horizontal and vertical positions in field under mulched drip irrigation of different water quotas and frequencies,moreover,the cotton yield was investigated. The experiment results show that,with fresh water and drip emitter discharge at 1.6 L·h^-1,excessive irrigation（450 mm）and sufficient irrigation（375 mm）can ensure appropriate water content in soil layers of 0～60 cm under film,and the moisture contents are the highest under excessive irrigation. On the contrary,the soil layers are in light-degree drought condition after bud stage under deficient irrigation（300 mm）. Low-frequent irrigation（10 days）and middle-frequent irrigation（7 days）can make the moisture suitable in soil layers of 0～60 cm,and the moisture contents are the highest under low-frequent irrigation. Contrarily,the soil layers are in light-degree drought condition during flowering and boll-forming stage under high-frequent irrigation（3 days）. The water quota and frequency of irrigation all have significant influence on the cotton yield,and the highest cotton yield can be obtained under excessive irrigation and high-frequent irrigation respectively among different water quotas,and frequencies.