Simulated Effects of Irrigation on Salinity in the Arkansas River Valley in Colorado
Simulated Effects of Irrigation on Salinity in the Arkansas River Valley in Colorado
复制标题
模拟灌溉对科罗拉多州阿肯色河流域盐度的影响
DOI：
--
复制
发表时间：
1998
期刊：
影响因子：
--
通讯作者：
Leonard F. Konikowd
中科院分区：
文献类型：
--
作者：
Karin Goff;M. E. Lewis;M. Person;Leonard F. Konikowd
农业灌溉对科罗拉多东南部的阿肯色州河下游流域的水量和水质有重大影响。采用二维水流和溶质运移模型评估灌溉变化对冲积含水层和阿肯色州河沿着17.7 km河段水量和水质的潜在影响。该模型进行了校准含水层水位和溶解固体浓度数据收集整个24年的研究期间（1971-95）。用校准模型模拟了两类灌溉管理：（1）减少用于灌溉的地下水抽取量;（2）停止所有地下水和地表水源的灌溉。在模拟的类别减少灌溉地下水抽水，有一个平均每月地下水盐度下降6.9%，平均每月河流盐度下降0.6%，地下水回流到河流增加11.1%。在所有灌溉停止的模拟类别中，月平均地下水盐度下降了25%;月平均河流盐度下降了4.4%;地下水返回河流的流量平均下降了64%。在所有的情况下，模拟地下水盐度相对于历史条件下降了约12年，然后达到一个新的动态平衡条件。含水层水位对任何模拟情景都不敏感。盐度的这些潜在变化可能会改善受影响地区下游灌溉用水的水质。
Agricultural irrigation has a substantial impact on water quantity and quality in the lower Arkansas River valley of southeastern Colorado. A two‐dimensional flow and solute transport model was used to evaluate the potential effects of changes in irrigation on the quantity and quality of water in the alluvial aquifer and in the Arkansas River along an 17.7 km reach of the river. The model was calibrated to aquifer water level and dissolved solids concentration data collected throughout the 24 year study period (1971–95). Two categories of irrigation management were simulated with the calibrated model: (1) a decrease in ground water withdrawals for irrigation; and (2) cessation of all irrigation from ground water and surface water sources. In the modeled category of decreased irrigation from ground water pumping, there was a resulting 6.9% decrease in the average monthly ground water salinity, a 0.6% decrease in average monthly river salinity, and an 11.1% increase in ground water return flows to the river. In the modeled category of the cessation of all irrigation, average monthly ground water salinity decreased by 25 %; average monthly river salinity decreased by 4.4 %; and ground water return flows to the river decreased by an average of 64 %. In all scenarios, simulated ground water salinity decreased relative to historical conditions for about 12 years before reaching a new dynamic equilibrium condition. Aquifer water levels were not sensitive to any of the modeled scenarios. These potential changes in salinity could result in improved water quality for irrigation purposes downstream from the affected area.