宁夏地区中南部干旱区域林草植被生态需水量研究

Ecological Water Requirement by Forest and Grass in Central and Southern Ningxia Hui Autonomous Region

以宁夏地区中南部干旱区域气象资料、植被分布、水资源状况等为依据,估算了现有林、草地生长季的最小和适宜生态需水量,并对降雨消耗性及径流消耗性林草地生态需水量进行了降水资源平衡分析。研究结果表明：（1）位于南部山区、年均降雨量在350~550mm之间的隆德和泾原县降雨消耗性林、草地最小和适宜生态需水量均能依靠降水得以满足,林草植被生长状况良好。（2）位于南部山区、年均降雨量在350mm左右的彭阳县和原州区,降雨能够满足林、草地最小生态需水量的需求,而适宜生态需水量不能得到满足。因此,该区域要合理考虑林草地种植结构。（3）年均降雨量在175~280mm,位于中部干旱带的海原、盐池和同心县以及南部山区的西吉县降雨消耗性林、草地最小和适宜生态需水量均不能得到满足。该区域不宜于大面积发展林草业。

Using the meteorological data,vegetation distribution data,water resources data,we calculated the minimum and appropriate ecological water requirement of existent forest and grassland in growing season in the Central and Southern Ningxia Hui Autonomous Region.Through the analysis of equilibrium between the eco-environment water demand and rainfall resource,the results showed that in Longde County and Jingyuan County,which locate in the south area,with an average rainfall of 350~550mm,the minimum and appropriate ecological water requirement both can be met by precipitation,and the vegetation grow well.In Pengyang County and Yuanzhou County,which locate in the south area,with an average annual rainfall of 350mm or so,the minimum eco-water demand can be satisfied,but appropriate ecological water demand cannot be met.So reasonable grass planting structure should be considered in the area.In Haiyuan,Yanchi and Tongxin Counties in the central arid area and Xiji County in the south area,with an average annually rainfall between 175and 280mm,both minimum and appropriate ecological water demand can not be met,it is unreasonable to develop forest and grassland in this area.