隰县试区降水生产潜势及其开发途径研究初探

隰县试区旱塬玉米产量随施肥量的增加划为三个区段:明显增长区段、平稳增长区段、负增长区段。以平稳增长区段最高产量的耗水系数或水分生产效率作为该地区的降水生产潜势值,经肥力梯度法测定为1.06～1.09kg/mm。培肥地力是提高降水生产潜势的基本途径,施肥促进农田耗水量增加10%左右,而水分生产效率却成倍增长,在施肥增产中起着主导作用。秸秆覆盖可少耗水30mm 以上,并提高水分生产效率19%。喷施抗旱剂能抑制蒸腾,改善植株水分状况,增产10%左右。

Study on Production Potentiality of Rainfall and Development Way in Xixian Experimental Area

The process of corn yield increasing with application rate was divided into three stages:obvious increasing stage,stable increasing stage and negative increasing stage in rainfall tableland,Xixian experimental area.Water consumption coefficient or water use efficiency at the peak yield of the stable increasing stage was taken for production potentiality of rainfall in the area and it was determined to be 1.06—1.09kg/mm by means of fertility gradient test.Improve- ment of soil fertility is the main way of increasing production potentiality of rainfall.Application increased the water consumption,rising about 10%,but water use efficiency were double.The rise of water use efficiency played most important role in the process of yield increase caused by application.Stalk mulch can decrease water consumption more than 30mm and increased water use efficiency of 19%.Spraying drought-resistant agent can control transpiration,improve water condition of plants and increase yield about 10%