干旱风沙区苜蓿后茬不同轮作方式对水分利用效率和产量的影响

Effects of Alfalfa Post-harvest Rotation on Water Use Efficiency and Crop Yield in Arid Sandy Area

为了评价宁夏干旱风沙区苜蓿翻耕不同轮作模式对水分恢复及适宜的轮作模式,研究了10a生紫花苜蓿翻耕后不同轮作方式对水分利用效率、产量和经济效益的影响。结果表明:苜蓿草地翻耕后不同轮作方式对土壤水分的恢复有一定效果,不同轮作方式土壤含水量有差异。轮作第1a玉米和高粱的水分利用效率与苜蓿地(CK)相比分别增加了1.14倍和1.09倍;轮作第2a苜蓿-玉米-玉米(ACC)和苜蓿-玉米-高粱(ACS)方式水分利用效率与苜蓿地相比分别增加了0.94倍和0.85倍;产量与苜蓿地相比分别增加了0.86倍和0.79倍;2a轮作结束后,ACS方式产投比高于其他轮作模式,是宁夏干旱风沙区最佳的草田轮作方式。

In order to evaluate the effects of different alfalfa-crop rotation modes on soil water restoration and economic efficiency in arid sandy area of Ningxia Hui autonomous region,the water use efficiency,crop yield and economic efficiency were analyzed in 10-year-old alfalfa grasslands after ploughing under different alfalfacrop rotation modes.The results showed that alfalfa-crop rotation affected soil moisture restoration but different rotation modes varied in their effects on soil moisture.1year after alfalfa post-harvest,the water use efficiency in fields under alfalfa-corn and alfalfa-sorghum rotation were 1.14 and 1.09 times higher than that in continuous alfalfa grassland（CK）,respectively.2year after alfalfa post-harvest,the water use efficiency in fields under alfalfa-corn-corn（ACC）and alfalfa-corn-sorghum（ACS）rotation increased by 0.94 and 0.85 times,respectively,while crop yields increased by 0.86 and 0.79 times,respectively,compared to those in continuous alfalfa grassland（CK）.The analysis of economic benefits in the two years showed that the average output to input ratio was higher under alfalfa-corn-sorghum（ACS）mode than under other rotation patterns.Therefore,alfalfa-corn-sorghum rotation was the most suitable grass-crop rotation pattern in arid sandy area of Ningxia Hui autonomous region.