摘要
建立三峡水库支流库湾富营养化模型,利用模型对三峡水库蓄水以来,香溪河支流库湾的水动力、总磷、总氮及叶绿素a(chl-a)浓度进行数值模拟,绘制水动力与同期实测的chl-a浓度在时间及空间域中的分布等值线,寻求水动力流速因子和chl-a浓度之间的相关关系,表明蓄水三年来藻华爆发期间库湾节点速度与chl-a浓度存在负相关,相关性可以采用对数曲线予以描述,根据相关点据的包络线方程可以由库湾流速预测可能出现的chl-a浓度峰值,结合上游来流及三峡水库水位的变动情况,预测chl-a浓度的演变趋势.数值模拟工作还表明,库水位50cm/d的降幅可对支流库湾chl-a浓度产生明显影响,但通过库湾水体的局部振荡或立面循环运行改善水动力条件的方法可能更具现实意义.
Numerical hydrodynamic and eutrophication model are developed and employed to predict the distribution of velocity and eco-factors, such as TP, TN, and chl-a in Xiangxi tributary of the Three Gorges Project. By analyzing the velocity and chl-a distribution in both time and spatial domains since water pounding, the negative correlation relationship between chl-a and velocity is found which can be described by logarithmic function. The up-envelop curve of the corrective point can be used to predict the possible peak value of chl-a in the tributary according to the equation combining with the velocity of flow. Numerical results also show that the concentration of chl-a will be decreased obviously while water level decreasing as 50cm/d. Considering the Comprehensive benefits of the reservoir, methods by enhancing the movement in the vertical cross-section such as vibrating and recirculating will be more valuable and practical for the improvement of hydrodynamic condition.
出处
《应用基础与工程科学学报》
EI
CSCD
2009年第5期652-658,共7页
Journal of Basic Science and Engineering
基金
国家自然科学基金项目(50779028)
国家科技支撑计划资助(2008BAB29B09)
