基于生态约束的萨拉乌苏组地下水优化管理模型研究

Optimal Groundwater Management Model for Salawusu Formation in Consideration of Ecological Constraint

萨拉乌苏组地下水广泛分布于生态环境脆弱的毛乌素沙地,规避地下水开发过程中的生态风险是一个亟需解决的关键技术问题。以ArcGIS为平台,采用Visual Modflow模拟软件,利用通用的优化模型软件GWM,以开采量最大化为目标,以对生态环境最小化为约束条件,研发了陕北能源化工基地地下水优化管理模型。结果表明,考虑了风沙滩地区地表植被生态约束后,全区开采量为70.44×104m3/d,其蒸发量较现状减少28.10×104m3/d,引起的河流排泄减少量仅占现状河流排泄量的4.09%,优化方案既保护了生态环境的完整性,又保证了河流基流量不明显减少,增加的开采资源量均来自减少蒸发量,优化开采方案合理可行,为陕北能源基地水资源利用提供技术支撑。

The Salawusu formation aquifer distributes widely in Mu Us desert which has extremely fragile ecological environment. Avoiding ecological risk in groundwater exploitation becomes a key technological problem. On the platform of ArcGIS,we employ Visual Modflow software and groundwater model( GWM) to build a numerical model of optimal groundwater management for the energy and chemical industry base of north Shaanxi province. The objective of the model is to ensure the maximum exploitation with minimum damage to eco-environment as constraint. Results show that in consideration of the ecological constraints,the exploitation amount is 70. 44 × 104m3/ d,the evaporation decreases by 28. 10 × 104m3/ d compared with the present situation,and the decrease of river discharge is only 4. 09% of the present discharge amount. The optimal scheme will protect the ecological integrity,and ensure that the base flow of the river doesn't decrease; moreover,the increase of groundwater exploitation comes from the decreased evaporation. In conclusion,the optimized exploitation scheme is reasonable and feasible,and provides technical support for the water resources utilization in North Shannxi energy and chemical base.