【摘要】 河流上筑坝发电将对水温、水质等生态环境产生影响。该文建立了三维水温水质耦合模型,以汉江上游安康水电站为例,选取COD(化学需氧量)和氨氮为水质指标,利用实测的水温、水质数据率定参数,对比分析单独计算和耦合计算其坝前垂向水温的差异性,模拟"引汉济渭"工程实施后逐月水温水质分布,总结耦合计算其库区水温、水质的变化规律。研究结果表明,耦合计算坝前垂向水温较单独计算反应灵敏,与库区实测水温更接近;耦合计算坝前水温在3月至9月呈弱分层状态,其余月份呈混合状态;对比不同年份的水电站下泄水温与坝址处天然水温可知,枯水年对水温影响最大,平水年次之,丰水年影响最小;坝前垂向氨氮、COD的分布规律基本与实测水温分布规律一致,受温度异重流影响,耦合计算的COD、氨氮分布规律与实际情况更相符合。更多还原

【Abstract】 The dam on river for power generation will change the water ecological environment factors, such as water temperature and water quality. Taking the Ankang hydropower station in the upper reaches of Hanjiang river as a case, a three-dimensional water temperature-water quality coupling model was constructed in this study. The parameters were calibrated based on the measured data of water temperature and water quality. Then, the monthly distribution of water quality and water temperature was simulated assuming that the Project of "Leading Han into Wei" has been completed. The comparative analysis of the reservoir water temperature and water quality variation on the conditions of individual and coupled working was indicated that: 1) the vertical water temperature presented weakly stratification during March to September, and mixed well in the rest months; 2) the temperature of discharge water was closer to the natural water temperature at dam site under coupling condition,therefore, the coupling results was more consistent with the measured; 3) the vertical distribution of COD and ammonia nitrogen of the coupling condition was basically consistent with vertical water temperature distribution, and hierarchical status of COD and ammonia nitrogen under coupled condition was significantly higher than individual conditions by the influence of temperature density flow impact.更多还原