龙羊峡水库蓄水对水温的净影响

分析水库蓄水对水温的影响对于研究水库气候效应,探讨水库建设对水生生物和下游农作物灌溉的影响具有重要意义。本文建立了计算分层型水库对水温净影响的数学模型,并利用龙羊峡水库和下游河道实测水温和气温成果,在深入分析了龙羊峡水库水温类型和水温铅直分布规律的基础上,采用该模型计算了龙羊峡水库蓄水对坝前和下游河道水温的净影响。与传统的差值法相比,该模型引入了基于气温与水温相关关系的修正因子,扣除了自然因素引起的水温背景值的变化,可以获得更为准确的计算结果。

Net Effects of Longyangxia Reservoir on Water Temperature

By pooling or slowing flow behind a dam, there are temperature changes both within the reservoir and downstream. Analysis of these changes have important significance in estimating effects of hydroelectric powers on the local climate, aquatics and crops. Based on long-term monitoring data, stratified temperature patterns occurred in Longyangxia reservoir on the upper sections of the Yellow River in Qinghai province is analyzed. Because of important impacts of air temperature on the top layer water temperature of a reservoir and a river, a new model is established to assess net impacts of Longyangxia reservoir on the water temperature within the reservoir and downstream of the dam. In comparison with conventional models, the new model adds correctional factor for relations of the air and water temperature and avoids impact of natural factors on changes of the water temperature, thus, resulting in exact calculating results.