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311.
312.
山东省东平湖浮游动物与富营养化防治 总被引:10,自引:0,他引:10
根据1994年对东平湖6个采样点枯水期,丰水期,平水期浮游动物的调查,共获轮虫,枝角类,桡足类和原生动物66属100种,查明其数量和分布以及季节变化状况,确定了指示轻污带,β-中污带和α--中污带的15个种及其分布,根据浮游统计结果。结果:其它方法,肯定了东平湖为中营养型一富营养型湖泊,按照综合防治富营养化原则,作者提出放养鲢鳙及搭配比较,以减少湖中着生藻类和浮游动物,防治富营养化,发展水产养殖业和旅游业,实现了可持续发展。 相似文献
313.
我国若干湖泊水库的营养状态指数TSI_c及其与各参数的关系 总被引:18,自引:4,他引:18
基于我国20多个湖泊水库的不同营养状态特征,首次得出了适用于我国若干湖泊的营养状态指数TSIc及其与各参数的关系,通过对这些湖泊的TSIc与TSIm值比较,指出TSIc比TSIm更适合于描述生物量与营养盐呈线性响应的我国这类湖泊的营养状态,此外还提出用相关加权法综合不同参数的营养状态指数,并用一个“综合”状态式来表示湖泊的营养状态。 相似文献
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315.
The loss of phosphorous (P) from the landscape is commonly viewed as deleterious for surface water quality. However, the quantities lost and the impact this can have on surface waters depends on numerous mechanisms that occur whilst en route. The aim of this review is to give an outline of these mechanisms and thus how sources of P in the agricultural landscape are connected to the impairment of surface water quality. Processes are dealt with by examining the potential for P loss from the landscape and its availability to aquatic plants during flow overland and subsurface flow and once in streamflow or a lake or reservoir. By examining the connectivity between P loss and the impact on surface water quality, potential mitigation and management of P losses are discussed for various aquatic systems. 相似文献
316.
湖泊水质富营养化评价的模糊隶属函数法 总被引:6,自引:1,他引:6
建立了利用模糊隶属函数进行湖泊水质富养化的评价方法。并研究了我国三个主要湖泊的富营养化状况,和其它方法比较,取得了满意的结果。文章为湖泊水质富营养化评价提供了一种简单而实用的评价方法。 相似文献
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318.
E. V. Yakushev V. S. Arkhipkin E. A. Antipova I. N. Kovaleva V. K. Chasovnikov O. I. Podymov 《Chemistry and Ecology》2007,23(1):29-41
The main objective of this work was to investigate the temporal variability of hydrochemical parameters in two coastal regions of the Northeastern Black Sea: the Gelendzhik bay, influenced by anthropogenic activities and the Golubaya bay an open coastal region. Dissolved oxygen, biochemical oxygen demand, pH, alkalinity, phosphate, organic phosphorus, silicates, nitrates, nitrites, ammonia, organic nitrogen, oil products and heavy metals were measured. Si/P and Si/N ratios showed that the Gelendzhik bay waters were significantly enriched in nitrogen and phosphorus compounds. Unlike the Golubaya bay, phosphates were always present in the Gelendzhik bay, and development of photo-synthesis was not limited by these. Features of seasonal variability of nutrients in the Gelendzhik bay (increased concentrations and pronounced summer-autumn maximum) appeared to be a result of human impact—outflow of nutrients with shore input and recreational activities during the summer holiday season. The data obtained indicate that pollution from local spots from the coast of the Black Sea, related primarily to eutrophication, could play a large role in the nutrient balance of the sea and could affect its ecological state. 相似文献
319.
水体富营养化问题评述 总被引:30,自引:2,他引:28
磷是水体富营养化问题产生的一个重要的原因。本文对磷污染产生的原因进行了调查 ,分析了各种污染的相对重要性 ,在此基础上对富营养化问题的预防和治理措施进行了综合分析和论述 ,指出解决富营养化问题应坚持预防为主 ,防治结合的原则。 相似文献
320.
Nine similarity indices based on phytoplankton community structure were examined for their sensitivity to assess different
levels of eutrophication. Two phytoplankton data sets, one from an open coastal system and one from a semi-enclosed gulf,
associated with different nutrient dynamics and circulation patterns were used for evaluating the indices. The results have
shown that similarity indices, measuring interspecific association and resemblance of phytoplankton communities between enriched
areas and control sites, were effective for detecting spatial and temporal dissimilarities in coastal marine ecosystems. The
structure of the oligotrophic habitat as a potential source of ambiguity for the results was discussed, whereas the validity
ranges and the potential applicability of this method were deemed to be dependent on the size of the fraction of the common
species among the samples, and the similarity of the classification patterns resulted from this subcategory and those extracted
from the overall community data. Furthermore, the study provides a new technique based on the use of the “Box and Whisker
Plot” designed to distinguish opportunistic and rare phytoplanktonic species. The similarity indices, applied solely to the
dominant species abundance, were more sensitive to resolve eutrophic, mesotrophic and oligotrophic conditions. This procedure
can be proposed as an effective methodology for water characterization and can also be used as a qualitative tracer for detecting
renewal processes of coastal marine ecosystems. 相似文献