渭干河灌区棉花高产节水优化灌溉制度试验研究

利用田测法进行了相同灌水时间和次数、不同灌溉定额条件下灌水量与棉花产量关系试验 ,并采用数学分析方法推导、分析、计算了棉花最高产量灌溉定额 ,节水经济灌溉定额 ,高效用水灌溉定额 ,棉花需水临界期。结果表明 :皮棉产量与灌水量呈良好的二次抛物线关系 ;节水经济灌溉定额不仅与棉花水分生产函数有关 ,而且与皮棉价格、单方水价格、生产要素不变费用及水费征收方式有关。在现状条件下 ,渭干河灌区棉花合理灌溉定额为 2 655～ 5394 m3/ hm2 ,最高产量灌溉定额为 5394 m3/ hm2 ,节水经济灌溉定额5370 m3/ hm2 ,高效用水灌溉定额为 2 655m3/ hm2 ;棉花需水临界期是花铃期和蕾期

Experimental Study on Optimal Irrigation Regime for High-Yield and Water-saving for Cotton in Weiganhe River Irrigation Area

Field experiment were carried out to study relationship between cotton yield and water application under condition of irrigated at same date, with same frequency, but with different irrigation quotas. The irrigation norms for the highest yield, for the highest water use efficiency, and for the highest benefits, and the critical period of water requirement in cotton are analyzed with mathematical method. Results show that relationship between cotton yield and irrigation norm can be described with a quadratic parabola. The irrigation norm for the highest benefits is related closely to water production function, cotton price, water charge, other production costs, and the way of collecting water charge. In Weiganhe river irrigated area, the rational irrigation norm, norm for the highest yield, norm for the best benefits, and norm for the highest water use efficiency for cotton are 2655～5394 m 3/hm 2, 5394 m 3/hm 2, 5370 m 3/hm 2, and 2655 m 3/hm 2 respectively. The critical periods of water application for cotton are flowering stage and budding stage.