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随着国家与公众对乡村生态环境的日益重视,如何对乡村河道进行有效修复成为当前的研究热点.现以闵行区浦锦街道为例,在对其水生态现状调研基础上,解析河道污染特征与污染物来源.并基于绿色生态修复的原则提出了在空间上通过生态缓冲区、河道及植物种植的方式构建河道生态系统的修复思路.进一步根据水体污染特性,制定了底质改良、紫外催化、沉水曝气、底部生物载体、生态浮岛、漂浮草垫、点源净化的内源污染防治技术措施.对比治理前后河道踏勘与水质检测结果显示:治理后河道水生态恢复较好、溶解氧浓度大幅提升、总磷得到了有效控制.后期可根据水体溶解氧浓度对曝气调控以促进对氨氮的去除效果.  相似文献   
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根据河道型水库特有的水文、水力条件,按各水期的不同情况分别将直角坐标系下的二维河流污染物扩散模型和极坐标下的AB卡拉乌舍夫扩散模型结合起来,建立了河道型水库的总磷预测模型,并将其应用于水深不超过5m的狭长型河道水库.以绵阳市三江水库为例,用此模型模拟并预测库区水体中总磷的浓度变化,计算结果与观测值的相对误差小于10%。  相似文献   
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We develop a layered “box model” to evaluate the major effects of estuarine eutrophication of the Szczecin lagoon which can be compared with integrating measures (chlorophyll a (Chl a), sediment burial, sediment oxygen consumption (SOC), input and output of total nutrient loads) and use it to hindcast the period 1950–1996 (the years when major increase in nutrient discharges by the Oder River took place). The following state variables are used to describe the cycling of the limiting nutrients (nitrogen and phosphorus): phytoplankton (Phy), labile and refractory detritus (DN, DNref, DP, DPref), dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and oxygen (O2). The three layers of the model include two water layers and one sediment layer. Decrease of the carrying capacity with respect to the increased supply of organic matter of the system with advancing eutrophication over the period studied is parameterized by an exponential decrease of the sediment nitrogen fluxes with increasing burial, simulating changing properties from moderate to high accumulating sediments. The seasonal variation as well as the order of magnitude of nutrient concentrations and phytoplankton stocks in the water column remains in agreement with recent observations. Calculated annual mean values of nutrient burial of 193 mmol N m−2 a−1 and 23 mmol P m−2 a−1 are supported by observed values from geological sediment records. Estimated DIN remineralization in the sediments between 100 and 550 mmol N m−2 a−1 corresponds to SOC measurements. Simulated DIP release up to 60 mmol P m−2 a−1 corresponds to recent measurements. The conceptual framework presented here can be used for a sequential box model approach connecting small estuaries like the Szczecin lagoon and the open sea, and might also be connected with river box models.  相似文献   
4.
本文对国内外湖泊富营养化控制技术的现状和发展及其在我国的应用进行了初步探讨,重点介绍了三种湖泊富营养化的控制技术。  相似文献   
5.
改进的模糊模式识别法在湖泊水体富营养化评价中的应用   总被引:4,自引:0,他引:4  
将模糊模式识别理论模型与级别变量特征值相结合,形成改性模糊模式识别法.并运用该方法对我国9个主要湖泊水体官营养化状况进行综合评价,研究表明改进的模糊模式识别法对水质进行评价,结果合理,方法可行,有一定的参考价值。  相似文献   
6.
The Oder River estuary is a large and complex system composed of lagoons, lakes and river branches in which numerous biogeochemical processes lead to modification of loads of dissolved/suspended material brought in with the riverine waters. Budget calculations show that on an annual basis, 71–88% of total nitrogen, 73–89% of total phosphorus and 72–101% of BOD5 inflowing to the estuary are exported to the Baltic Sea. Among the inorganic nutrient species, nitrates exhibit the highest net transformation rate into organically bound forms (over 60%). The transformation could have been equally high or even higher in the case of ammonia and phosphates but these processes may have been compensated by intensive mineralization. The mechanisms responsible for the nutrient transformation patterns, as well as their net effect on the annual loads delivered into the Baltic Sea, are discussed in the paper. Phosphorus seemed to play a limiting role in phytoplankton production in the estuary in spring, while nitrogen did the same in summer.  相似文献   
7.
An ecological numerical model has been developed for coastal zone management in Dokai Bay, Japan. The numerical model experiment reproduces the occurrence of red tides and oxygen-deficiency in Dokai Bay during summer. Moreover, the model experiments forecast that when the phosphorus or nitrogen load from land will be cut by 90% or 95%, respectively, red tides and oxygen-deficiency will not occur in Dokai Bay. If the sewage facility is not sufficient to cut the nutrients load to the necessary degree, it is necessary to consider other countermeasures such as cultivating bivalves in order to decrease the nutrients in the bay.  相似文献   
8.
富营养化景观水体一直以来是国内外水处理的难题。针对这种水体修复效果差、藻类多、溶解氧低、氮磷含量高、透光性小等特点,从物化处理方法和生物处理两个方面综述了国内外这种类型水体的处理技术,根据各种方法的特点,分析了其优势和不足,提出了未来该类水体的主要研究方向,为实践中该类水体的治理提供参考。  相似文献   
9.
内河挖入式港池内水体交换缓慢,富营养化污染问题常有发生,影响港口正常运营和绿色发展。从分析挖入式港池水环境特点、富营养化产生原因入手,阐述兼顾水体治理与景观效果的生态浮岛原理及技术要点。以某内河港池为例,在不影响码头运营的条件下,研究港池生态浮岛治理方案,分析运行费用。初步成果分析表明,通过合理配置生态浮岛,可有效控制水体富营养化、改善水质并营造港池绿色景观,为绿色港区建设提供技术支撑。  相似文献   
10.
Resource managers are often tasked with identifying and assessing the potential impacts of management actions on the biotic communities under their care. When the management activities directly influence a single species of interest, managers can turn to a variety of models to aid in their understanding of potential changes to that population. However, as ecosystem-based management becomes more widely accepted, managers will have to understand how proposed actions will impact entire biotic communities, through both direct and indirect mechanisms. Thus, there is a need for ecosystem models that account for both trophic and non-trophic interactions, and that can be relatively easily used to assess a variety of management scenarios. We reviewed the available literature regarding incorporation of eutrophication and other anthropogenic impacts into Ecopath with Ecosim (EwE), one of the more widely used trophic ecosystem modeling frameworks. We found that a number of mechanisms of varying complexity have been used to include these stressors in models, providing managers with a suite of options that can be used to complement their existing management options as they seek to understand the impacts of human interactions on the natural environment.  相似文献   
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