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41.
杞麓湖主要污染物的动态变化特征研究   总被引:1,自引:0,他引:1  
以1997年杞麓湖水质监测结果为基础,运用相关分析,双因子方差分析等方法,对杞麓湖主要污染物动态变化特征的研究结果表明,杞麓湖主要污染物的空间分布较为均匀;BOD5和TN都有较为明显的季节变化。  相似文献   
42.
以抚仙湖水环境地理信息系统为例,论述了GIS技术在水环境保护方面的具体应用,着重对系统的总体设计、系统的功能模块、系统的数据库设计以及系统建立的技术策略进行了详细的描述与论证。说明了利用GIS技术对湖泊环境管理工作带来的巨大便利。系统的建立对保护抚仙湖湖区环境,促进沿湖周边县市乃至整个云南省的经济发展都具有重要的现实意义。  相似文献   
43.
Phytoplankton assemblages in the subtrophical oligotrophic Lake Fuxian, the second deepest lake in China, were investigated monthly from September 2002 to August 2003. A total of 113 species belonging to seven phyla were identified, among them, a filamentous green alga, Mougeotia sp., dominated almost throughout the study period and comprised most of the total phytoplankton biomass.Mougeotia sp. has made a substantial development during the past decades: it was absent in 1957, only occasionally present in 1983,increased substantially in 1993, and became predominant in 2002--2003. It is likely that natural invasion of the Taihu Lake noodlefish (Neosalanx taihuensis) has led to a change of dominant herbivorous zooplankton from small to large calanoid, which has increased grazing pressure on small edible algae, and thus has indirectly favored the development of the inedible filamentous Mougeotia sp.  相似文献   
44.
二叠纪—三叠纪之交的环境恶化事件不但导致了生物大绝灭,而且造成了自然界正常的碳循环崩溃。为了研究三叠纪早期生物复苏过程中的环境特征、碳氧同位素演化上的地层学意义,对巢湖平顶山西坡剖面下三叠统碳酸盐岩取样分析。研究结果表明,巢湖平顶山西坡剖面早三叠世碳氧同位素地层曲线与已知的平顶山北坡剖面碳氧同位素地层曲线相似。δ13C值在Induan阶、Olenekian阶底部首先表现为大幅度负漂,随后呈上升趋势。δ18O值除了表现出1Ma的周期性波动之外,与δ13C低值区对应处也具负偏趋势。δ13C、δ18O值的演化趋势反映了早三叠世海洋环境恶化、生物复苏十分缓慢。  相似文献   
45.
RS、GIS在内陆湖泊水质研究中的应用   总被引:12,自引:0,他引:12  
:遥感 (RS)、地理信息系统 (GIS)技术的综合应用在许多研究领域广泛推广并日渐成熟 ,表现出广阔的发展前景。将 RS、GIS相结合 ,综合应用于内陆湖泊水质的监测和分析 ,充分体现了其快速、经济、高效的强大优势。本文首先回顾了一般监测方法的特点及局限性 ,主要讨论了 RS、GIS的特点及在内陆湖泊监测和分析中的优势所在。最后提出了此领域的发展方向展望  相似文献   
46.
青海省盐湖卤虫资源的开发与保护--以尕海湖为例   总被引:1,自引:0,他引:1  
通过在青海省的实地考察和对尕海湖周边植被的调查,总结出造成青海省尕海湖卤虫产量减少的影响因素,得出防治对策,并对若干卤虫开发利用的问题进行了讨论,为青海省卤虫资源的保护与开发提供参考。  相似文献   
47.
The process of eutrophication in form of intense plant growth has been observed in some lakes and water streams at the Plitvice Lakes National Park in central Croatia. Here we investigate whether this phenomenon is a consequence of anthropogenic pollution or due to naturally produced organic matter in the lakes. We applied chemical analysis of water at two springs and four lakes (nutrients, dissolved organic carbon (DOC), trace elements) and measurements of surface lake sediments (mineral and organic fraction analyses, trace elements) in four different lakes/five sites. The chemical composition of water does not indicate recent anthropogenic pollution of water because the concentrations of most trace elements are below detection limits. The concentrations of DOC and nutrients are slightly higher in the area of increased eutrophication-plant growth. Also the content of organic matter in the sediment is at the highest level in areas with highest C/N ratio indicating that the organic fraction of this sediment is mainly of terrestrial origin. There is no significant difference among the trace element concentration in the upper segment of all cores, deposited approximately during last 50 years when higher anthropogenic influence is expected due to development and touristic activity, and the lower part of the cores, corresponding to the period approximately 100–200 years before present. The content of trace elements and organic matter in sediments decreases from the uppermost lake downstream. According to our results there is no indication of recent anthropogenic pollution in water and sediment. Higher concentrations of DOC in water as well as phosphorus and some other elements in the lake sediment can be a consequence of input of natural organic matter to the lake water.  相似文献   
48.
我国湖泊富营养化问题及防治对策   总被引:25,自引:0,他引:25  
史丹 《资源开发与市场》2005,21(1):17-18,27
富营养化是我国湖泊的主要问题,它不但制约了湖泊资源的可利用性,而且直接影响到人类的健康生存与社会经济的持续发展.分析了我国湖泊富营养化的现状、危害、产生的原因,提出了防治对策.  相似文献   
49.
阐述了旅游区域联动发展战略的内涵、类型、原则及意义,分析了安徽省"两山一湖"地区实施旅游区域联动战略的必要性、可能性和发展现状,提出了若干对策.  相似文献   
50.
Sedimentation rates and sediment provenance were examined for lacustrine sediments deposited in Fairfield Lake, western North Carolina, during the past 111 years. Stratigraphic, radionuclide, and cartographic data indicate that sedimentation rates have increased several fold during the past three decades in response to localized development. The magnitude of increased sedimentation was surprising given limited development within the basin: 0.12 to 0.68 buildings/ha in 2000 in those parts directly delivering sediment to the dated cores. Thus, the analysis illustrates the potential sensitivity of watersheds in the southern Appalachians to changes in land cover. An approach that combined geochemical fingerprinting with sediment mixing models was subsequently evaluated to determine its ability to accurately estimate the contribution of sediment from (1) major bedrock formations that underlie the watershed and (2) potential sources associated with four land cover categories. Sediment sources in both analyses proved difficult to geochemically fingerprint to greater than 90 percent accuracy using data on acid‐soluble metals and selected isotopes of lead (Pb). The relative contributions of sediment from delineated sources, estimated by the mixing models, generally corresponded with known temporal and spatial patterns of land cover. However, the models were plagued by two significant problems — the chemical alteration of sediments as they were transported through upland streams to depositional sites within the lake and the loss of elemental mass. Thus, future investigations using the fingerprinting approach in this area of intense weathering, and presumably others, will need to modify the existing methods to more accurately elucidate changes in sediment provenance related to development.  相似文献   
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