摘要
基于包含浮游动物作用的一维水质生态数学模型 ,考虑了长江水位的顶托作用 ,采用有限体积法 ,建立了汉江水质生态数值模型 ,用 1992年的实测资料进行参数识别 ,对汉江 1995年至 1998年的水动力、氨氮、硝氮、凯氏氮、总磷、溶解氧 (DO)、生化需氧量 (BOD) ,以及浮游植物的迁移转化规律进行了数值模拟 ,模拟结果与实测资料吻合较好 ,说明所建的模型符合汉江下游河段的实际情况。数值模拟结果表明 :当汉江下游水体有机物含量较高 ,水温 6℃以上和光照充足时 ,汉江下游河段适宜藻类生长 ,易发生“水华”现象。特别在枯水季节 ,在流量较小和流速低的情况下 ,水体中藻类会过快生长。藻类的生长速度因各断面的流速、水深和水面宽的不同而不同。
A one-dimensional water quality model in low reaches of the Hanjiang River is developed, which combines a process based on hydrodynamic model with numerical description of phytoplankton production, zooplankton grazing, nutrient cycling, the oxygen budget and particle dynamics. The water quality component consists of ammonia, nitrate, ortho-phosphate, dissolved oxygen, chlorophyll-a, biochemical oxygen demand, organic nitrogen, organic phosphorus and zooplankton grazing. Field data of 1992 were used to parameterize the models. The hydrodynamic model was simulated in river flow field. The numerical simulations of the hydrodynamic and water quality from 1995 to 1998 provide satisfactory results in comparison with corresponding measurements. The result clearly demonstrated that algae have a high growth rate with higher nutrient concentration,6℃ rise of water temperature, and plenteous light. Algal growth rate is different with average velocity, water depth and cross-section width.
出处
《长江流域资源与环境》
CAS
CSSCI
CSCD
北大核心
2002年第4期363-369,共7页
Resources and Environment in the Yangtze Basin
基金
湖北省自然科学基金 ( 2 0 0 1ABB0 48)资助项目
