微咸水膜下滴灌对棉花净光合速率、蒸腾速率及产量的影响研究

微咸水资源的开发利用可有效缓解灌溉水源短缺问题，合理利用微咸水灌溉将是极端干旱荒漠区今后农业灌溉发展的必然趋势。通过开展不同微咸水配比混灌处理，研究了微咸水灌溉对棉花净光合速率、蒸腾速率及其产量的影响。研究结果表明：在阳光充足时，当灌水定额分别为20mm、25mm、30mm时，咸淡1：1和2：1配比灌溉后的棉花日净光合速率、蒸腾速率的均值满足20mm〉30mm〉25mm。在试验数据分析的基础上，建立了土壤水分与蒸腾速率，土壤水分与净光合速率相关关系模型。通过随机取值验算，2号试验地咸淡2：1处理后的蒸腾速率与土壤水分具有较好的相关关系，其实测值与计算值误差小于10％。

Study on Impacts of Net Photosynthetic Rate , Transpiration Rate and Cotton Yield by Salin Water Irrigation under Film Drip

Exploitation and utilization of saline water can effectively help alleviate irrigation water scarcity, so development of low - quality water for irrigation will inevitably become the future development tendency of agricultural irrigation in extremely arid desert. In- fluences of saline water irrigation on net photosynthetic rate, transpiration rate and yield of cotton were studied in this paper through ir- rigation experiments with different ratio of salt water to fresh water. The results showed that, when the quotaes on irrigation were set at 20mm, 30mm and 25m respectively, both mean of net photosynthetic rate and mean of transpiration rate of cotton were decreasing, no matter the ratio of salt water to fresh water blended in irrigation water was 1 ： 1 or 1：2 in sunny day. A relationship model among soil moisture, transpiration rate and net photosynthetic rate was established based on the analysis on the experiment. Test with random val- ues proved that, there was a closer relationship between transpiration rate and soil moisture on No. 2 trial field irrigated with the water where the ratio of salt water to fresh water was 2：1. The deviation between measured value and calculated value was less than 10% o