【作者】 安斐；

【导师】 陶建华；

【作者基本信息】 天津大学 ， 流体力学， 2007， 硕士

【摘要】 由于人口的快速增长,经济的快速发展和海岸高度开发,使入海营养盐负荷不断增加,从而导致近岸海域富营养化问题不断加剧,已严重制约了滨海地区经济的可持续发展。富营养化的预测与评价模型的建立,对于近岸海域富营养化的防治、修复和管理具有重要的意义。本文以渤海湾为研究背景,通过分析渤海湾中与富营养化有关的主要因素,综合了化学指标、浮游植物指标并考虑到细菌指标,提出了渤海湾海水富营养化的二级模糊综合评价方法,对渤海湾富营养化状态进行了评价,并用加权平均原则对结果进行了处理。对评价结果进行排序,发现渤海湾北部近岸海域和南部的养殖区富营养化程度严重,且夏季最高,秋季最低。运用生态排序方法对2004年和2005年渤海湾浮游植物分异进行了研究,并运用局部CCA排序方法分析了空间格局和环境因子对浮游植物分异影响的大小。除十月份外,空间格局对浮游植物分异的影响都超过了环境因子对浮游植物分异的影响。在各环境因子中,磷酸盐对浮游植物分异的影响最大,其次为硅酸盐、盐度。根据排序结果对渤海湾的生态区域进行了划分。根据生态排序划分的区域,选择赤潮监控区建立模糊逻辑富营养化模型。选择了TN和TP作为模型的输入,并考虑了温度和当前叶绿素值的影响。以赤潮监控区三个站位的实测数据建立了模型的模糊规则库,并用这三个站位的叶绿素值对模型的输出进行了拟合,表明规则库满足了基本要求。对赤潮监控区的一个站位进行了模拟研究,运行结果大部分与实测值接近。更多还原

【Abstract】 Nutrient salt load into sea increased owing to fast rise of population, rapid development of economic and high exploitation of coast. It aggravated eutrophication of coastal water which has heavily restricted sustainable development of coastal economic. Establishing of assessment model and prediction model for eutrophication will do important signification to repair, management, prevention and cure of coastal water eutrophication.The study in this paper is based on Bohai Bay. Through analyzing main factors related to eutrophication in Bohai Bay and synthesizing chemistry index and phytoplankton index and bacteria index also considered, the method of two-grade fuzzy synthesis assessment for seawater eutrophication is put forward. The method is applied to assess the eutrophication level in Bohai Bay and the result is transformed by weighted-average principle. Through arranging final assessment result,it can be found eutrophication is serious in north costal water and south fishery of Bohai Bay. The level of eutrophication is the highest in summer and lowest in autumn.Phytoplankton distribution differentiation of Bohai Bay in 2004 and 2005 was studied by ecological ordination method, and influence on phytoplankton distribution differentiation by spatial distribution pattern and environment factors was analysed by local CCA ordination method.The influence on phytoplankton distribution differentiation by spatial distribution pattern is lager than by environment factors except in October.In the environment factors, P influenced phytoplankton distribution differentiation most following silicate and salinity. Ecological area in Bohai Bay was partitioned according to the result of ordination.According to areas partitioned by ecological ordination method, red-tide survey and control area was selected to establish fuzzy logic eutrophication model. TN and TP were selected as input of model and the influence of temperature and current chlorophyll was also considered.Fuzzy inference rules were established based on survey data of three stations in red-tide control area. Output of model was fitted by chlorophyll value of these stations which indicated rules are basically satisfied. The other station was simulated and most of the results were close to fact value.更多还原