黄土旱塬不同供水处理玉米产量效应研究

A Study on the Yield -response of Corn to Different Treatments of Water Supply in Non-irrigated Plateau of Loess

该文在田间遮雨棚下模拟土柱试验和田间小区试验数据的基础上，对黄土旱塬不同供水处理玉米的产量效应进行了定量研究。结果表明：在模拟土柱试验中，玉米生物产量、经济产量随土壤湿度或耗水量的增大而呈抛物线变化规律递增；玉米生物量水分生产率、籽粒水分生产率则随耗水量的增大而按双曲线变化规律递减。田间小区试验中，玉米产量与耗水量之间亦呈正相关的抛物线关系，玉米籽粒水分生产率的最小值出现在灌水量为零的干旱处理，可籽粒水分生产率的最大值则出现在灌水量极少的次干旱处理，土壤耗水也随灌水量的增加而减小，土壤耗水占总耗水量的百分比则随灌水量的增加按指数函数变化规律下降。

Two experiments both of simulation under rainproof shelter and plot in field have been done to study the yieldresponse of corn to different treatments of water supply in Non-irrigated Plateau of Loess. The results show that ,inthe field simulation column experiment ,the biomass and the grain yield of corn are increased parabalically with theincreaseL of the soil moisture or the total water consumption, but the crop water use efficiency is hyperbolically de-creased with the increase of the total water consurnption, In the field plot experiment,the grain yield of corn is in-creased parabalically with the increase of the total water consumption too, the minimal crop water efficiency can bernade in the dry treatment, but the maximal crop water use efficiency can be rnade in the treatment of low watersupply(i.e, ,the irtigation quota is 70 mm per Mu),with the increase of the irrigation(quota,the soil water depletionis decreased,and the percent age of soil water depletion in total is exponentially decreased.