红壤丘陵区作物耗水需水的研究

本文利用水分蒸渗仪对赣东北低丘红壤区的几种主要作物（花生、水稻、荞麦）需水耗水规律进行了研究，其结果表明：生产１ｋｇ的花生荚果需要消耗１．３１ｍ３水量用于作物腾发；生产１ｋｇ的稻谷则需要消耗０．７６ｍ３水量用于作物的腾发；而生产１ｋｇ荞麦籽实需要消耗１．２３ｍ３水量用于作物的腾发。与其对应的水分利用率（ＷＵＥ）分别为７．６５ｋｇ／ｍｍ·ｈｍ２、１３．９５ｋｇ／ｍｍ·ｈｍ２和８．１０ｋｇ／ｍｍ·ｈｍ２。作为一般规律，作物的产量在一定范围内与腾发量成线性关系，因此，每公顷产３０００ｋｇ花生需要３９３０ｍ３（或３９３ｍｍ）的水量维持腾发；每公顷产７５００ｋｇ水稻则需要５７００ｍ３（或５７０ｍｍ）的水量用于腾发；而每公顷产３７５０ｋｇ的荞麦籽实产量需４６０５ｍ３（或４６１ｍｍ）的水量。在田间条件下，设计作物需水量时还应考虑地表径流和水分的渗漏与下渗的情况。试验结果还表明：水稻的水分利用率要高于花生和荞麦，在规划和配置灌溉水时，应优先考虑水稻的供水。

Study on the Water Consumption and Demand of Crops in Red Soil of Hilly Region

Water demand and consumption of staple crops (peanut, rice, buckwheat) in red soil of hilly region of Northeast Jiangxi Province were studied in this paper by using lysimeters. Results indicated that water consumption for evapotranspiration during the formation of 1kg grains was 1.31m 3 for peanut, 0.76m 3 for rice, and 1.23m 3 for buckwheat, and the corresponding water use efficiency (WUE) was 7.65, 13.95 and 8.1kg/ha.mm, respectively. Generally, crop production in certain range is linearly related with evapotranspiration. Thus, to obtain 3000kg/ha peanut production, 3930m 3 (393 mm) is needed for evapotranspiration, while this demand for rice of 7500kg/ha output and 3750kg/ha buckwheat was 5700m 3/ha (570mm) and 4605m 3/ha (461mm), respectively. Under field conditions, surface runoff, water infiltration, and drainage should be taken into consideration when designing water demand for crops. It is also suggested that priority should be put on water supply for rice in irrigation planning since the results showed that WUE for rice was higher than that for both peanut and buckwheat.