高关灌区中稻田间水利用系数试验研究

Field Water Utilization Coefficient of Middle-season Rice in Gaoguan Reservoir Irrigation District

【目的】测算分析高关灌区灌溉水利用系数,提高水资源优化配置和实现最严格水资源管理决策。【方法】以高关灌区中稻试验田为样本,采用平均法、实测法、对比实测法分别测算了高关灌区中稻田间水利用系数。【结果】3种方法测算所得系数分别为0.903、0.941和0.921,相差不大,误差在5%以内,其中,实测法所得系数最大,平均法所得系数最小。高关灌区中稻田间水利用系数随灌水定额增大而减小,呈负相关关系;对比实测法与实测法相比,认为田面渗漏是稻田的有效耗水,田埂渗漏则是稻田的无效耗水,避免了中间测定造成的累积误差,适用于稻作区田间水利用系数的测定。【结论】对比实测法测算的高关灌区中稻田间水利用系数为0.921是合理的。

【Objective】Provide scientific basis for the calculation and analysis of irrigation water utilization coefficient,optimal allocation of water resources and the most stringent decision-making of water resources management in Gaoguan Irrigation Districts.【Method】Taking the middle-season rice field in Gaoguan Reservoir Irrigation District as the sample,the field water utilization coefficient of middle-season rice was calculated by means of average method,measuring method and contrast measuring method.【Result】The results show that the coefficients calculated by the three methods were 0.903,0.941 and 0.921,respectively.The coefficient measured by the measuring method was the largest and the coefficient calculated by the average method was the smallest.However,the coefficients calculated by the three methods were not very different and the error was less than 5%.The conclusions show that the field water utilization coefficient of middle-season rice in Gaoguan Reservoir Irrigation District decreases with the increase of irrigation quota,showing a negative correlation.Compared with the measuring method,it was considered that the field leakage was the effective water consumption of paddy field,and the ridge leakage was the ineffective water consumption of paddy field,which avoided the cumulative error caused by the intermediate measurement and is suitable for the determination of field water utilization coefficient in paddy field.【Conclusion】It is reasonable that the field water utilization coefficient of middle-season rice in Gaoguan Reservoir Irrigation District is 0.921 by contrast measuring method.