基于耗水平衡分析的区域水资源管理

传统的供水管理和需水管理难以满足水资源可持续利用的要求,从耗水管理角度出发,以区域耗水平衡为理念,采用SWAT模型对河北省馆陶县基于蒸腾蒸发(ET)的水资源管理进行了分析,模拟了小白龙灌溉、低压管灌和喷灌3种不同节水灌溉方式下分别对应的6种作物种植结构调整模式(共18套水资源管理方案)的区域耗水水平。研究结果表明,低压管灌和喷灌两种节水灌溉方式对于减少区域ET量的作用与其所减少的取水量相比差距较大,真实节水效果并不十分显著。影响区域ET的主要因素是降水,区域ET量在湿润年份明显要高于干旱年份。这一规律并不随着灌溉方式和作物种植结构调整而发生根本性变化。灌溉对冬小麦生育期ET量的影响要显著高于对玉米生育期ET量的影响,减少冬小麦种植面积可以有效降低区域ET量。因此,馆陶县实现区域耗水平衡的最佳灌溉管理方案是灌溉方式为喷灌、冬小麦种植面积减少20%且全部改种为棉花。研究结果可为区域水资源管理和水资源高效利用提供参考。

Water consumption balance analysis-based regional water resources management

As the conventional water supply management and water demand management are difficult to meet the requirement of the sustainable utilization of water resources，the ET -based water resources management of Guantao County in Hebei Province is analyzed herein with SWAT model from the aspect of water consumption by taking the regional water consumption balance as the idea，in which the regional water consumption levels of 18 sets of water resources management schemes respectively corresponded to 6 modes of crop planting structure adjustment are simulated under three different water-saving irrigation modes，i. e. hose irrigation，low-pressure pipe irrigation and sprinkler irrigation. The study result shows that a large difference is there between both the water saving irrigation modes of low-pressure pipe irrigation and sprinkler irrigation for their roles to reduce the regional ET if comparing with the reductions of the amounts of the water-intaking from them，and then the real water saving effect is not so significant. The main factor to influence the regional ET is precipitation，and then the regional precipitation during wet year is obviously higher than that of the dry year. This law is not to be fundamentally changed along with the adjustments of both the irrigation mode and the crop planting structure. The influence from irrigation on the ET of the winter wheat growth period is obviously higher than that of the summer maize growth period，thus reducing the planting area of winter wheat can effectively lower the regional ET. Therefore，as the optimal irrigation management scheme for realizing the regional water consumption balance in Guantao County，the finally chosen irrigation mode is sprinkler irrigation，while the winter wheat planting area is reduced by 20% ， which is all replaced by cotton planting. The study result can provide some references for the regional water resources management and efficient utilization of water resources concerned.