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1.
申锐莉  鲍征宇 《地质通报》2005,24(10):988-996
湖泊湿地生态地球化学评价的研究重点为湖泊湿地生态系统中的重金属、植物营养元素及一些有机污染物,评价标准体系相应地包括水质基准、营养物基准、水体沉积物质量基准、饮用水卫生标准、土壤环境质量标准、食品卫生标准、湖泊水库富营养化标准等。  相似文献   

2.
湖泊湿地生态地球化学评价的研究重点为湖泊湿地生态系统中的重金属、植物营养元素及一些有机污染物,评价标准体系相应地包括水质基准、营养物基准、水体沉积物质量基准、饮用水卫生标准、土壤环境质量标准、食品卫生标准、湖泊水库富营养化标准等.  相似文献   

3.
李敏  成杭新  李括 《地学前缘》2018,25(4):276-284
利用中国150余个淡水湖泊表层沉积物和深层沉积物的地球化学数据,采用中位数绝对中位差的方法统计获得了中国主要淡水湖泊沉积物的As、Cd、Cr、Cu、Hg、Ni、Pb、Zn、TN、TP、TOC及pH的地球化学背景值,为我国湖泊沉积物环境质量基准的建立和湖泊生态环境质量监管提供了重要依据。统计结果表明,我国表层湖泊沉积物中的As、Cd、Hg等重金属元素以及TP、TOC等发生了显著富集,显示出强烈的人类活动对湖泊沉积物环境质量的改变。在探讨国外环境质量基准值对我国淡水湖泊沉积物环境质量评价适应性的基础上,提出直接采用国外相关标准还不能客观评价我国湖泊沉积物的污染程度和生态风险,应充分考虑我国湖泊沉积物的地球化学背景,建立适应我国情况的沉积物环境质量基准。  相似文献   

4.
云南断陷盆地岩溶湿地众多,是云南高原生态系统的重要组成部分,但因各种原因,造成湖泊淤积、水面面积缩小以至消亡,滇东地区的湖泊退化较为明显,近30年内有20多个天然湖泊过早消亡。文章开展滇东岩溶断陷盆地内具有代表性的通海湖泊退化型(杞麓湖湿地)、泸西地下水聚积型(黄草州湿地)、宣威地下河淤塞型(格宜串珠状湿地)三种类型典型岩溶湿地研究,主要研究湿地的成因类型及特征、湿地“三场”(径流场、水化学场、温度场)特征,分析岩溶断陷盆地内天然形成的湿地地质条件、水文地质条件、水环境影响因素及定量评价水环境质,以及岩溶湿地自然及人为影响因素、影响形式、作用强度、效应和水源减小、污染加剧、水质下降、湿地萎缩等及其生态环境问题。研究结果表明,通海湖泊退化型(杞麓湖湿地)受人为和自然因素影响较大,水质水量是其退化的主要原因;泸西地下水聚积型(黄草州湿地)受湿地内地下补给、净化、修复,水质总体较好;宣威地下河淤塞型(格宜串珠状湿地)受区域地下水水位变化影响,地下水总体丰富。文章研究成果为岩溶断陷盆地湿地的保护、科学研究、利用、生态修复提供地质依据。  相似文献   

5.
杨娟  黄燕  陈有明 《华东地质》2019,(4):273-279
利用MSS、ETM+、CBERS-2、BJ-2、02C和TH1多时相卫星遥感数据,分别提取1975年、2000年、2007年和2016年皖江经济带湿地现状及变化的遥感信息,研究皖江经济带湿地遥感现状及变化规律。结果表明:皖江经济带湿地类型主要为河流湿地、湖泊湿地、沼泽湿地和人工湿地,市县级地域湿地分布不均、类型不全;1975—2016年,人工湿地面积增加,增长率为55.32%;沼泽湿地面积减少,减少率为69.97%;湖泊湿地和河流湿地面积较稳定,增长率分别为1.80%和2.06%。湿地变化分两个阶段:第一阶段(1975—2007年),湿地面积总体增加,河流湿地、湖泊湿地和沼泽湿地面积减少,人工湿地面积增加;第二阶段(2007—2016年),湿地面积总体增加,但河流湿地和湖泊湿地面积增加,沼泽湿地面积继续减少,人工湿地面积继续增加,湿地面积增减受人类活动影响较大。  相似文献   

6.
陈钰  雷琨  杜尧  马腾 《地球科学》2021,46(2):661-670
沉湖湿地作为长江中下游平原典型湖泊湿地,1960s以来退化严重.收集1964、1975、1987、1997、1998、2007、2016、2018年8期航拍照片或遥感影像,运用遥感技术、动态度模型和转移矩阵模型分析,揭示武汉市沉湖湿地近50年退化过程及机理.结果表明,1964~2018年沉湖湿地由北向南退缩为鱼塘及耕地,总湿地面积缩小77%;湿地退化过程可分为3个阶段,1964~1975年围湖活动主导湿地湖泊向耕地退化,耕地面积以141%的年变幅扩张,1975~1997年湖泊改造工程迫使湖泊向沼泽退化,1997~2018年由湖泊退化而来的沼泽被进一步开垦为耕地或鱼塘;人口数量的增加及土地利用政策改变导致湿地生态服务功能退化,包括洪水调蓄、自净化功能衰退及生物多样性锐减,其退化模式可为长江中下游平原乃至全国湖泊湿地的退化提供类比参考.   相似文献   

7.
新疆博斯腾流域湿地遥感监测及时空变化过程   总被引:4,自引:0,他引:4  
博斯腾流域是新疆最大的湖泊湿地分布区。湿地作为干旱区的一种特殊景观类型,在流域生态环境和水循环中发挥了重要的作用,其产生和消失、扩大和萎缩对区域生态环境将产生重要的影响。以Landsat系列数据为主要数据源,完成了博斯腾流域的3期遥感制图(1990、2000、2010年),分析了博斯腾流域湿地分布现状,探讨了区域湿地的时空变化过程和动态变化特征。结果表明:新疆博斯腾流域的湿地面积总体上一直在萎缩,1990-2010年总面积减少了16.24%;但是减少趋势相对变缓,且不同类型的湿地变化过程有所不同。其中:1990-2000年河流湿地和湖泊湿地表现为增加趋势,芦苇沼泽湿地表现为减少趋势;2000-2010年河流湿地、芦苇沼泽和湖泊湿地面积都表现为萎缩。在变化动态特征上,流域河流、湖泊湿地最近20a呈现倒"V"型波动,而芦苇沼泽湿地则持续下降。通过湿地变化与区域生态环境因子耦合分析表明,在近期内人类活动是造成区域湿地萎缩的主要因素。  相似文献   

8.
霍林河流域生态环境需水量研究   总被引:1,自引:0,他引:1  
李青山  周林飞  王教河  李兴春  李金祥 《水文》2006,26(4):27-31,84
根据霍林河流域的具体情况,其生态环境需水量由河流基本功能生态环境需水量和通河湖泊湿地需水量组成。其中河流基本功能生态环境需水量又包括保持水体自净能力用水和河流基本生态环境需水量。综合分析生态环境需水的现有计算方法。结合霍林河流域河流、湖泊、湿地生态系统类型的特点,建立适合于研究区域不同生态系统类型的生态环境需水计算方法。以土地利用遥感动态分析为基础,对霍林河流域各生态系统类型的生态环境需水量进行计算,扣除重复计算部分,基准年和各规划水平年生态环境需水量为85 976万m~3/a,再扣除产流量(18 865万m~3/a)和流域内三个自然保护区的沼泽湿地对应的多年平均降水量(17244万m~3/a),需要霍林河流域和外流域提供的水资源量为49867万m~3/a。  相似文献   

9.
概要地回顾了近年来国内外湖泊沉积物中重金属环境污染方面的研究成果,介绍了湖相沉积物重金属研究的主要内容、方法和可能的发展方向。认为就重金属成因方面应加强区分其主要来源是岩石和矿物风化的碎屑产物、大气降尘、人类活动等的研究;重金属污染方面更应重视污染物质的生物有效性、迁移转化机理和重金属“二次污染”的研究;研究手段上,注重运用同位素示踪与定年技术来研究重金属的来源和污染历史,应用高分辨率沉积物钻心研究环境的变迁。最后提出加强多学科的综合研究,建立中国湖泊基准数据库,为探讨湖泊湿地的可持续发展提供依据。  相似文献   

10.
湖泊沉积物中重金属的环境地球化学   总被引:1,自引:0,他引:1  
概要地回顾了近年来国内外湖泊沉积物中重金属环境污染方面的研究成果。介绍了湖相沉积物重金属研究的主要内容、方法和可能的发展方向。认为就重金属成因方面应加强区分其主要来源是岩石和矿物风化的碎屑产物、大气降尘、人类活动等的研究;重金属污染方面更应重视污染物质的生物有效性、迁移转化机理和重金属“二次污染”的研究;研究手段上,注重运用同住素示踪与定年技术来研究重金属的来源和污染历史,应用高分辨率沉积物钻心研究环境的变迁。最后提出加强多学科的综合研究,建立中国湖泊基准数据库,为探讨湖泊湿地的可持续发展提供依据。  相似文献   

11.
Distribution of AVS (acid volatile sulfide)-SEM (simultaneously extracted metals), transformation mechanism and risk assessment of heavy metals in the Nanhai Lake in Baotou City were discussed in this work. The results showed that the content of heavy metals in sediments increased due to the water pumped from the Yellow River, domestic sewage, municipal runoff and yacht waste release. Increasing water depth, domestic sewage influx and hydrophyte booming made the AVS level higher in downstream than upstream. The vertical distribution of AVS is characterized as multiple-peak in the sediment cores from the studied lake. Comparatively, the control abilities of the carbonate and sulfate to the heavy metals were five orders of magnitude lower than the sulfide phase. Therefore, AVS was the key factor controlling the precipitation of heavy metals in the Nanhai Lake. The ratio of SEM/AVS in the sediments, the acute sediment quality criteria and the chronic sediment quality criteria indicated that no acute toxicity for benthic organisms can be expected, and the AVS plays an important role in controlling the bioavailability and toxicity of heavy metals in the Nanhai Lake.  相似文献   

12.
成都平原农田区土壤重金属元素环境基准值初步研究   总被引:5,自引:0,他引:5  
土壤重金属污染已成为制约人类社会发展及危害人类健康的重要因素,制定土壤重金属元素的环境基准值对控制土壤重金属污染及保护生态安全具有重要意义。以成都平原农田区为例,以保护地下水安全为目的,以室内模拟淋溶实验为手段,尝试性地计算了研究区不同类型土壤重金属元素的环境基准值。研究结果表明:(1)不同类型土壤各元素在土壤—水间的分配系数差异较大;(2)不同类型土壤Hg和Cd环境基准值差异不大,Hg环境基准值平均为0.3μg/g,Cd的变化范围为0.3~0.5μg/g;As和Pb环境基准值差异较大,As的变化范围为18~24μg/g;Pb的变化范围为24~41μg/g;(3)研究区土壤基本处于保护饮用水的安全范围之内,但黄壤中Pb、紫色土中Cd和Pb、棕壤中Hg和Pb具有潜在的影响地下水安全的生态风险。这对研究区进行风险评估具有重要的参考价值。  相似文献   

13.
The heavy metal accumulation in soils caused by industrialization has attracted broad attention. To evaluate the soil environmental quality of Xiangyin County, an important food production base in China, 99 top paddy soil samples were analyzed for total concentrations of As, Cd, Cr, Cu, Hg, Ni, Zn and Pb. Kriging interpolation was used to determine the spatial distribution of the metals. The assessment of soil environmental quality was performed according to pollution index methods. As the results showed, except for Cu, Cr and Ni, the mean concentrations of Zn, Pb, Cd, As and Hg in soils were elevated to different extents when compared with the background values. Moreover, except for Cd, contents of seven other elements in most soil samples were below the Class II criteria for Chinese environmental quality standards, which established the maximum allowable concentration of heavy metal in the farmland. Therefore, the soils were believed to be polluted mainly by Cd. All of the elements showed a similar spatial distribution pattern with low contents in the east upland area, and high contents in the middle by the west area, located close to Dongting lake. The long-term practice of using the Xiangjiang river as irrigation water was believed to be the main reason resulting in the enrichment of heavy metals in soils around Dongting lake. In addition, the evaluation results showed that about 45.8, 51.1 and 3.1?% of the study area were classified as slightly, moderately and seriously polluted with Cd, respectively. As for the other seven elements, soil environmental quality was fairly well because of their grades belonging to clean or excellent. By integration of the assessment results for individual elements, it was found that about 3.8?% of the study area was clean, 82.2?% was slightly polluted and 14.1?% was moderately polluted. On the whole, most of the study area was at safe and guarded level. However, appropriate measures still should be adopted to control the levels of heavy metals in agricultural soils. The findings obtained in this study were useful for establishing policies for protecting the local soil environments and guaranteeing the food quality as well as the people??s health.  相似文献   

14.
A comprehensive assessment on lake water quality was carried out in Shahu Lake, northwest China, to provide valuable information about present lake water quality for decision making. Major ions, general parameters, bacteriological parameters, organics and trace metals monitored monthly in 2014 were considered. Monitored parameters were compared with quality criteria for surface water of China, and overall water quality assessment was carried out using an entropy weighted water quality index (EWQI) based on 20 selected parameters. Lake water quality was also assessed for irrigation purpose. The results show that the lake water is of Cl·SO4–Na facies with high salinity and COD. The geochemistry of the lake water is regulated by intense evaporation and human activities. TP, TN and F? are major inorganic contaminants, with over 50% of the water samples polluted by them. Oil, mainly attributed by leaky motor tourist boats, is the major organic pollutants in the lake water, with 10 samples (37.04%) showing higher oil content than the permissible limit. The concentrations of other inorganic and organic contaminants as well as trace metals are well below the permissible limits. The present study indicates that inorganic contamination in the lake water is more severe than organic pollution. The overall lake water quality, assessed by EWQI, is poor and very poor with SO4 2?, TDS, TH and Cl? being the dominant contributing factors. The lake water is suitable for irrigation in terms of alkalinity, but is unsuitable for irrigation from the salinity point of view. Accelerating the circulation and replenishment of the lake water is an important way of reducing contaminant concentrations. This study is important in providing comprehensive information on lake water quality for decision makers and valuable reference for international lake water researchers.  相似文献   

15.
武汉市墨水湖沉积物重金属污染特征与防治对策   总被引:8,自引:2,他引:8  
苏春利  王焰新 《矿物岩石》2006,26(2):111-116
武汉市墨水湖重金属污染严重,其污染特征在我国城市湖泊中具代表性。在对墨水湖不同湖区沉积物中重金属污染物空间分布特征进行分析的基础上,应用地积累指数法探讨不同重金属元素含量随深度变化的规律和原因,并对墨水湖沉积物中重金属的污染程度进行评价表明:墨水湖沉积物中重金属元素锌和汞污染最为严重,污染程度由高到低依次为:Zn>Hg>Cu>C r>Pb>A s;从整个湖区来看,分布有排污口的周边湖区污染严重,湖心污染程度较低;沉积物中主要重金属元素含量随深度增加而降低,其变化规律主要受污染状况的影响,沉积物颗粒粒径的变化和早期成岩作用的影响不大。为了改善墨水湖水质条件和重金属污染严重的现状,必须在截污、疏浚和引水工程等基本治理措施保护下,重建和恢复沉水植物系统,才能从根本上改善湖泊水质。  相似文献   

16.
Five sediment cores from the fresh water region of the Vembanad wetland system were studied for the trace element contents The average concentration of iron, manganese, nickel, copper, zinc, cadmium, lead, mercury and chromium were determined. The core samples were collected using gravity type corer, digested with a mixture of nitric acid and perchloric acid and analyzed by atomic absorption spectrophotometry. Heavy metals such as iron, copper, nickel and zinc reported enrichment towards the surface of the core sediment sample collected from the centre of the lake. Lead, cadmium and mercury showed uniform distribution through out the core. Quality of the sediments were evaluated based on sediment quality guidelines, pollution load index, sum of toxic units and with effect range low/effect range median and threshold effect level/probable effect level values of Environmental Protection Agency guidelines. The degree of contamination for each station was determined. The concentration of different heavy metals has been compared with the world average concentration of shale values. Results of the analysis showed that Vembanad lake is facing serious metal pollution with increased rate of deposition.  相似文献   

17.
Dissolved trace elements and heavy metals of waters and sediments in the ten shallow lakes in the middle and lower reaches of the Yangtze River region were determined to identify their composition and spatial distribution, and to assess the extent of their environmentally detrimental effects by comparison with water and sediment quality guidelines. Results indicated that As and Pb were the main pollutants in lake waters and Mn and Hg the potential ones, while As, Cu and Pb were the main pollutants in lake sediments. Their spatial distribution indicated that Daye Lake was seriously polluted by metals, which was corroborated by cluster analysis. Higher concentrations of trace elements have been found in lakes downstream of the Yangtze River delta, and higher concentrations of metals have been recorded in sediments of upstream lakes, suggesting that metals in water were more sensitive to anthropogenic activities and that metals in sediment were mainly controlled by minerals. Correlation analyses demonstrated that there were stronger associations among metals in lake sediments than those in lake waters, and their good relationships suggested the common sources. Further research on the subject will help develop water quality management with the aim of restoring shallow lakes in the Yangtze River.  相似文献   

18.
Gökçekaya Dam is one of the dams located on the Sakarya River (Eski?ehir) in Turkey and is approximately 38 years old. No study regarding to the water quality of the dam lake has been hitherto made. This study aimed at determining the seasonal variations with physical, chemical, and biological parameters of the water quality of the dam lake. Depth-wise water samples were taken from five selected stations, in seasonal periods during 2005–2008, and anlayzed. The quality of water was classified in accordance with the results and taking into consideration many parameters. At the same time, number and type diversities of dissolved heavy metals and algae population were analyzed. Using principal component analysis (PCA) and classification analysis (CA) methods, differences between these parameters and samples from stations have been determined . The analysis showed that Gökçekaya dam lake, formerly an oligotrophic lake, has become a mesotrophic lake. And according to the results thereof the Lake has mezotrophic characteristics due to the sudden changes (including household waste water inflow and opening the Sar?yar dam lake shutters) in certain periods and in some stations. Hierarchical clustering analysis, revealed no significant difference between the measured parameters. And according to the Water Pollution Control Regulations in Turkey (WPCR) Gökçekaya dam lake is in the first class quality in terms of anions, cations, heavy metals, temperature, and pH values. However, the is of first class quality presence of nitrite reduces the water quality in the lake and causes this lake to be classified in the fourth class quality.  相似文献   

19.
Water, soil, suspended load and biomass samples were collected from a sewage and sludge treated lake (Lake Dalavayi) around Mysore, Karnataka, India. The polluted lake water is mainly used for irrigation and domestic purposes. The samples have been analysed for heavy metals (Cu, Cr, Co, Cd, Ni, Fe, Mn, V, Zn, Sr) and cations (Ca, Na, Mg) by Inductively Coupled Plasma Emission Spectrometer (ICP) model Labtam 8500. With the exception of water, all the matrices suspended particulate matter, lake bed sediment and biomass of the lake show high concentrations of heavy metals and cations when compared to the World Health Organization (WHO) standard, indicating metal toxicity in this lake. Additional inputs of soaps and detergents carried by sewage water are causing the eutrophication of the lake. Elevated levels of heavy metal toxicity, especially Co and Cd, are indicated by the bioindicator Eichornia cressepes (water hyacinth), which, using these metals as micronutrients, has grown luxuriously over the lake water, further augmenting the death of lifeforms in the lake.  相似文献   

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