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1.
长江中下游湖泊富营养化过程的湖泊沉积记录   总被引:5,自引:1,他引:5  
长江中下游湖群区,历来是人类最活跃的场所,但由于近年来社会经济的迅速发展,湖泊富营养化问题日趋严重,对湖泊湿地变化与湖泊营养盐状况关系的分析是制定湖泊环境整治和生态修复的重要科学依据。长江中游湖泊——龙感湖的湖中心钻孔沉积物中硅藻组合和总磷变化记录了近百年来龙感湖富营养化过程。沉积物中湿地花粉与人湖营养盐关系以及磁化率的分析表明,流域内人类活动对湖周滩地的改造,破坏了湿地植被,助长了人湖物质的增加,湖泊营养相对富集,而流域农业化肥的使用导致了水质的进一步恶化。  相似文献   

2.
秦皇岛主要入海河流污染及其对近岸海域影响研究   总被引:3,自引:0,他引:3  
李志伟  崔力拓 《生态环境》2012,(7):1285-1288
利用饮马河、洋河、汤河和戴河的水文和水质监测资料,分析了各河流的污染状况、营养状态、污染物入海通量及其对海域水质的影响。结果表明:秦皇岛市入海河流中饮马河和洋河污染较重;通过污染分担率分析,秦皇岛入海河流的首要污染物为DIN、COD,其次为PO43--P;采用综合营养状态指数法评价,汤河处于轻度富营养状态,戴河处于中度富营养状态,而洋河和饮马河都已达到重度富营养化状态,可见秦皇岛入海河流的富营养化现象非常严重;秦皇岛主要河流污染物入海通量近年来基本呈减小趋势,饮马河和洋河年均入海污染物量占到秦皇岛市陆源入海污染物总量的94.91%;通过相关分析表明,秦皇岛近岸海域的水质主要受入海河流影响,尤其是CODMn、DIN、PO43--P在河、海间存在线性关系,具有强相关性。因此应加强对入河污染物的管理,重点应放在生活污水、农业面源污染的治理上,从而改善近岸海域的水质状况。  相似文献   

3.
In this study, levels of Fe, Cu, Cd, and Ni in the sediments and organs of Phragmites australis from three different sites in the Anzali wetland were measured. Heavy metal accumulation was higher in the roots of P. australis than in the shoots and leaves. There was a significant correlation between metal concentrations in roots and sediment. This result showed that the root of P. australis can be used as bioindicator for Fe, Cu, Cd, and Ni. Metal levels in sediment were recorded higher than the interim sediment quality guideline values, and the Cd and Ni content in P. australis were higher than the unpolluted levels in plants. This indicates the necessity for continuous monitoring of the metal levels and also evaluating the hazard risk of heavy metals in aquatic organisms in the Anzali wetland.  相似文献   

4.
《Ecological modelling》2003,159(2-3):223-238
The effectiveness of exergy and specific exergy indices as ecological indicators of the trophic state of lake ecosystems is here tested on a small homogeneous set of shallow lakes which, in spite of their similar nutrient concentrations, morphology and hydrology, show a different trophic state and structure, species composition and abundance. The findings reveal that exergy and specific exergy indices have good negative correlation with phytoplankton biomass and Carlson's trophic state index (TSI) and strong positive correlation to water transparency (the relationship between exergy and eutrophication is clearer if the exergy refers to surface units, rather than volume units) and, hence, that they may be used as ecological indicators of the trophic state of lake ecosystems. The relationship between the responses of the thermodynamic approach and other conventional trophic classification methods (Vollenweider's eutrophication model based on phosphorus loading, the Hillbrich-Ilkowska method and the Vollenweider–OECD classification criterion) previously applied to Lake Trasimeno, was also investigated. The decreasing trend of exergy and specific exergy indices with eutrophication increase appears to be essentially due to the change in species composition and trophic structure, rather than to a different trophic potentiality of the ecosystems investigated. Concerning the identification of the environmental factors responsible for exergy and specific exergy trends, the coherence of the correlation structure between water depth, TSI, exergy and specific exergy indices, suggests that the lake's mean water depth plays a significant role in determining the changes in trophic structure and state (and consequently in exergetic indices) within the set of lakes examined and emphasises the importance of lake morphology in the development and ageing of lake ecosystems.  相似文献   

5.
贵州草海湿地农田渠系水质空间分异特征及影响分析   总被引:4,自引:0,他引:4  
夏品华  薛飞  孔祥亮  刘燕  林陶 《环境化学》2012,31(8):1201-1207
为了解草海湿地农田渠系水质现状、空间分异特征及影响因素,于2011年秋季对草海湿地进行大空间尺度的采样,分析了氮磷等理化指标,采用单因子污染指数法和营养状态指数法分别对农田渠系水质和湖泊营养状态进行评价.结果表明,草海湿地农田渠系水质污染严重,多数水质为V类或劣V类,总氮和溶解氧是水体中的主要污染因子;上游水质劣于下游,尤其是上游靠近县城区域的水质最差;多等级排水渠系对氮磷具有一定的截留作用,干渠V级水质好于低级渠系水质;不同的土地利用方式对水质的影响不同,城镇用地>集中式村落>农田;草海湿地水体上、中、下游营养水平分别为中度富营养、轻度富营养和中营养,外源污染物的累积和湖泊营养水平的提高导致其沼泽化,而流域不合理的土地利用结构加剧了沼泽化的进程.  相似文献   

6.
湖泊营养物基准的候选变量和指标   总被引:5,自引:0,他引:5  
湖泊营养物基准指标变量是可用于衡量水质、评价或预测水体的营养状态或富营养化程度的变量,是构成建立区域和湖泊营养物基准的基础。详细介绍和分析了氮、磷两个营养物变量和有机碳、叶绿素、透明度、溶解氧、大型植物、生物群落结构等生物学指标,以及营养状态指标、自养指数、温度、pH值、电导率以及土地利用等一系列相关变量(度量或指标),并总结了当前美国各州在湖泊营养物基准指标选取方面的基本情况。归纳出选择营养物基准指标时应遵循的若干原则,即综合考虑富营养化控制关键因子和区域差异性,所选指标应具有相对稳定、早期预警和易于监测等特点。最后针对我国湖泊营养物基准指标的选取提出了几点建议。  相似文献   

7.
研究各种水质因子(水温、溶解氧、电导率、pH、营养盐等)对三峡库区支流水体富营养化的驱动效果,为库区支流水体富营养化的防控与治理提供科学依据.于2018年11月至2019年10月在三峡库区高阳平湖进行了12次样品采集,获取了水温、水体pH、营养盐、水体溶解氧等指标数据,利用主成分分析法研究三峡库区支流水体富营养化状况,...  相似文献   

8.
淮北市采煤塌陷区土壤养分状况   总被引:1,自引:0,他引:1  
研究了淮北市采煤塌陷区内湿地(南湖湿地、东湖湿地)、园林绿地、耕地3种土地利用类型土壤的养分含量情况.结果显示:湿地中受人为干扰强烈的南湖湿地土壤全氮量为1.128g/kg,显著高于园林绿地,与人为干扰弱的东湖湿地和耕地无显著差异;湿地有机质含量南湖为23.781 g/kg,东湖为11.250 g/kg,二者之间无差异...  相似文献   

9.
2007年7月~2008年5月按季度对丹江口水库4个库区(丹江库区、汉江库区、取水口和五青入库区)的水环境和浮游生物进行了调查,采用生态系统健康指数(EHI)法和营养状态指数(TSI)法对该水库的生态系统健康状态进行定量的综合评价.结果表明:2007年7月~2008年5月,丹江口水库整体处于中营养状态,健康状态中等,健康状态总趋势是丹江库区>取水口>汉江库区>五青入库区;各库区生态系统健康状态存在季节性差异,丹江库区、取水口两库区全年为中等,汉江库区在夏季为较差,其它季节中等,五青入库区在冬季最差,其它季节较差.此外,对两种评价方法进行了比较,表明丹江口水库属于响应型生态系统,生态系统健康指数(EHI)适用于丹江口水库生态系统健康的评价.  相似文献   

10.
Spatial distribution of nutrient and phytoplankton variables is often illustrated using categorical mapping for each variable. However, the assessment of eutrophication cannot be derived from a single parameter since a synthesis of the environmental variables related to eutrophication is required. These shortcomings are further complicated since it is difficult to discriminate between distinct trophic states along natural environmental gradients. In the present work, a methodological procedure for quantitative assessment of eutrophication at a spatial scale was examined in the Gulf of Saronicos, Greece, based on a thematic map generated from the synthesis of four variables characterising eutrophication. The categorical map of each variable was developed using the Kriging interpolation method and four trophic levels were indicated (eutrophic, upper-mesotrophic, lower-mesotrophic and oligotrophic) based on nutrient and phytoplankton concentration scaling. Multi-criteria choice methods were applied to generate a final categorical map showing the four trophic levels in the area. This synthesis of categorical maps for assessing eutrophication at a spatial scale is proposed as a methodological procedure appropriate for coastal management studies.  相似文献   

11.
Taking 29 Chinese lakes and 29 Italian lakes as two separate case studies, the paper presented the variations of exergies and structural exergies along eutrophication gradients in Chinese and Italian lakes. The exergies (Ex) and structural exergies (Exst) were calculated based on phytoplankton biomass (BA) and zooplankton biomass (BZ). A trophic state index (TSI) scaling from 0 to 100 was developed to classify trophic status for Chinese and Italian lakes based on three indicators, chlorophyll-a concentration (Chl-a, in mg/m3), total phosphorus (TP in mg/m3) and transparency in Secchi disk depth (SD in m). The relationships between TSI and Ex, Exst, total biomass, BZ/BA ratios were analyzed. The following results were obtained: (1) with the increase of TSI in Chinese and Italian lakes, there is an increasing trend for Ex, and a decreasing trend for Exst, generally. The obvious negative correlations exist between TSI and Exst, at the significant level of 0.01 for Italian lakes, and 0.05 for Chinese lakes. The obvious positive correlations exist between TSI and Ex, at the significant level of 0.01 for Chinese lakes, and for Italian lakes in Spring, Autumn and the all-year. (2) The structural exergy is more dependent on the ratio of phytoplankton biomass to zooplankton biomass (BZ/BA) than the exergy, and the exergy is more dependent on total biomass than the structural exergy. (3) The phytoplankton biomass (BA) and zooplankton biomass (BZ) are increased with the increasing TSI in Chinese and Italian lakes, and phytoplankton biomass (BA) increases more rapidly then zooplankton biomass (BZ) does. This results in the definite decrease of BZ/BA ratio with the increasing trophic status index. Such changes of BA, BZ and BZ/BA ratio could explain successfully the variations of exergies and structural exergies along eutrophication gradients in Chinese and Italian lakes. From the two separate case studies of Chinese lakes and Italian lakes, it could be concluded that exergy and structural exergy are feasible to serve as the system-level ecological indicators to give appropriate information on the trophic status of different lakes.  相似文献   

12.
珠江口磨刀门轮虫群落结构特征与水质生态学评价   总被引:1,自引:0,他引:1  
轮虫是浮游动物群落中的重要组成部分,对水质变化反应敏感,调查轮虫群落的种类组成和丰度变化,可以获知水质变化和水体的营养状况,并可作为水质评价依据。于2009年7月至2010年1月,对珠江口磨刀门3个站点(S1滞水区、S2河道和S3水流交汇区)轮虫群落结构特征进行每月两次的调查,同时测定了水温、盐度、透明度、叶绿素、总氮、总磷等理化指标,利用非生物环境因子对水体的营养状况进行了TLIc加权综合营养状态指数评价,并通过轮虫种类组成、E/O指数、QB/T指数和生物多样性指数对水质进行了生态学评价。调查期间,水温12~29℃,盐度0.11~7.9 PSU,叶绿素a浓度0.89-9.56μg·L-1,叶绿素a与水温呈显著正相关(p〈0.0001),与盐度呈显著负相关(p〈0.01)。磨刀门水域3个采样站点TLIc处于50~60之间,表明其水质均达到轻度富营养水平,富营养程度按S1、S2、S3依次递减。调查期间,共记录轮虫56种,S1站点轮虫种类最多,其中污染指示轮虫42种。污染指示种占轮虫总数比例表明,珠江口磨刀门达到了富营养化水平,与利用非生物环境因子作出综合营养状态指数TLIc的评价结果一致。磨刀门的优势种为广布多肢轮虫(Polyarthra vulgaris)、螺形龟甲轮虫(Keratella cochlearis)、热带龟甲轮虫(Keratella tropica)和暗小异尾轮虫(Trichocerca pusilla)。调查期间,轮虫丰度在S1、S2、S3变化范围分别为0~199 ind·L-1、1~54 ind·L-1和0~48 ind·L-1,平均丰度分别为31±54 ind·L-1、13±15 ind·L-1和11±13 ind·L-1。丰水期的8月下旬轮虫丰度达到最大值;枯水期丰度均较低。轮虫丰度与水温、总氮、叶绿素显著正相关(p〈0.05),与盐度显著负相关(p〈0.05)。磨刀门河口理化因子变化剧烈,轮虫多样性指数波动范围较大,反映出河口水域轮虫群落结构的不稳定性。冗余分析(RDA)表明水温、盐度和叶绿素是影响轮  相似文献   

13.
镇江内江湿地植物群落演替过程中土壤养分动态研究   总被引:6,自引:0,他引:6  
镇江内江湿地是由长江携带的泥沙在镇江内江特有的水文条件下淤积而成,形成于江滩裸地上的植物群落开始了群落的原生演替过程。在此过程中,湿地的土壤养分状况随着植被的演替更迭,发生着协同演化的过程。为了进一步丰富群落演替理论,通过研究群落演替过程中不同阶段以及同一演替阶段不同层次土壤养分状况的时空变化,探索演替过程中的不同植被类型和土壤养分变化的内在联系及其互作效应。结果表明,随着演替进行,土壤的养分状况趋于改善,土壤有机质、全氮和速效磷含量呈上升趋势,只有速效钾的含量在后期芦苇阶段明显降低,这主要是由于收割芦苇将富含钾素的芦苇植株带出湿地系统所致。由于植物根系分布及枯落物多少的差异,使得各营养成分的垂直分布各异。  相似文献   

14.
River waters in China have dual contamination by nutrients and recalcitrant organic compounds. In principle, the organic compounds could be used to drive denitrification of nitrate, thus arresting eutrophication potential, if the recalcitrant organics could be made bioavailable. This study investigated the potential to make the recalcitrant organics bioavailable through photocatalysis. Batch denitrification tests in a biofilm reactor demonstrated that dual-contaminated river water was short of available electron donor, which resulted in low total nitrogen (TN) removal by denitrification. However, the denitrification rate was increased significantly by adding glucose or by making the organic matters of the river water more bioavailable through photocatalysis. Photocatalysis for 15 min increased the Chemical Oxygen Demand (COD) of the river water from 53 to 84 mg·L-1 and led to a 4-fold increase in TN removal. The increase in TN removal gave the same effect as adding 92 mg·L-1 of glucose. During the photocatalysis experiments, the COD increased because photocatalysis transformed organic molecules from those that are resistant to dichromate oxidation in the COD test to those that can be oxidized by dichromate. This phenomenon was verified by testing photocatalysis of pyridine added to the river water. These findings point to the potential for N removal via denitrification after photocatalysis, and they also suggest that the rivers in China may be far more polluted than indicated by COD assays.  相似文献   

15.
Estuaries and coastal lagoons are characterized by a strong spatial and temporal variability of physicochemical characteristics and productivity patterns. In these environments, the magnitude and direction of the ecological responses to inorganic nutrient increase (i.e. eutrophication) are difficult to predict. In the framework of the project, New Indicators of Trophic state and environmental quality of marine coastal ecosystems and transitional environments (NITIDA), we analysed benthic indicators of trophic state, ecosystem efficiency, and environmental quality in four different transitional environments. The trophic state of the sediments was assessed in terms of quantity and bioavailability of sediment organic C pools; ecosystem efficiency was determined in terms of the prokaryote efficiency in exploiting enzymatycally degraded organic C; environmental quality was determined in terms of meiofaunal diversity. Here, we provide a synopsis of the results obtained and a meta-analysis of the scores assessments obtained using the different ecological indicators of environmental quality and demonstrate that trophic state, ecosystem efficiency, and biodiversity in transitional ecosystems are closely linked. We conclude that the assessment of the environmental quality of transitional ecosystems should be based upon a battery of trophic state indicators and ‘sensors’ of ecosystem functioning, efficiency, and quality.  相似文献   

16.
Estuaries and coastal lagoons are characterized by a strong spatial and temporal variability of physicochemical characteristics and productivity patterns. In these environments, the magnitude and direction of the ecological responses to inorganic nutrient increase (i.e. eutrophication) are difficult to predict. In the framework of the project, New Indicators of Trophic state and environmental quality of marine coastal ecosystems and transitional environments (NITIDA), we analysed benthic indicators of trophic state, ecosystem efficiency, and environmental quality in four different transitional environments. The trophic state of the sediments was assessed in terms of quantity and bioavailability of sediment organic C pools; ecosystem efficiency was determined in terms of the prokaryote efficiency in exploiting enzymatycally degraded organic C; environmental quality was determined in terms of meiofaunal diversity. Here, we provide a synopsis of the results obtained and a meta-analysis of the scores assessments obtained using the different ecological indicators of environmental quality and demonstrate that trophic state, ecosystem efficiency, and biodiversity in transitional ecosystems are closely linked. We conclude that the assessment of the environmental quality of transitional ecosystems should be based upon a battery of trophic state indicators and 'sensors' of ecosystem functioning, efficiency, and quality.  相似文献   

17.
江苏省不同营养状况湖泊底栖动物群落结构与多样性比较   总被引:3,自引:0,他引:3  
为了解江苏省湖泊底栖动物群落结构和多样性并研究其对水环境质量变化的响应,于2012年春秋两季对江苏省16个湖泊51个采样点湖泊底栖动物群落结构与多样性以及湖泊综合营养状态指数进行调查,分析水质指标与底栖动物指数间Pearson相关关系。结果表明,江苏省16个湖泊营养状态指数范围为35.5~66.4,其中约81.2%的湖泊处于轻度-中度富营养状态,表明水质从好到中度污染;湖泊底栖动物优势种为寡毛类的霍甫水丝蚓(Limnodrilus hoffmeisteri),优势度为13.0%;香浓多样性指数(Shannon-Wiener diversity index)范围为0.00~2.20,级别范围由极贫乏到较丰富状态,表明水质污染程度从重度到轻度污染。从全省尺度看,水质评价结果与生物学(香浓多样性指数、Pielou均匀度指数和Biotic Index(BI)指数)评价结果存在一定差异。与历史数据相比,江苏省湖泊底栖动物清洁敏感物种减少甚至消失,总体群落结构趋于小型化。16个湖泊水体总氮和总磷与底栖动物密度呈显著负相关,而综合营养状态指数与底栖动物指数(香浓多样性指数、Pielou均匀度指数和BI指数)间关系不显著。上述研究结果表明综合营养状态指数无法完全客观反映湖泊水生态健康状况,因此需要综合水质、水文、水生生物、生境状况等因素发展新的评价指标体系。  相似文献   

18.
An effective measure to cope with eutrophication of lakes is to remove nutrients that can cause algal blooming by taking advantage of natural water purification processes. Here the term “purification” is defined, in a wide sense, as the potential role of a water body to contribute to the reduction of pollutants and thus controlling eutrophication. Also regarded as a kind of ecological regulating services, biological purification involves various processes concerning seasonal nutrient fixation, such as uptake by aquatic macrophytes, biofouling onto foliage substrates, feeding by organisms in higher trophic level, and eternal loss or removal of substance from the water. In order to evaluate the water purification ability, a numerical lake ecosystem model highlighting the role of macrophyte colonies in the shore zone was developed and applied to Lakes Suwa, Kasumi and Biwa, as well as five small lakes attached to Lake Biwa.  相似文献   

19.
基于1:25万河流水系和数字高程(DEM)数据制备了选取湖泊的流域边界,据其集成了流域社会经济数据,并据中国科学院资源环境数据中心提供的1990、1995、2000、2005年4个时段土地利用数据形成了流域反映人类活动强度的表征指标,选取了全国湖泊富营养化区域差异性调查课题获取的案例湖泊的水质数据,集成了中国湖泊富营养化影响因素计量分析的面板数据集,研究了1990-2005年间中国湖泊营养状态的发展趋势与差异特征,探讨了湖泊富营养化的自然气候与社会经济影响机制,构建了中国湖泊富营养化影响因素分析的计量模型,厘定了1990-2005年间影响湖泊营养状态变化的重要因素,测度了其对湖泊富营养化的影响方向和作用强度。基于面板数据的计量分析结果表明,近15年人类活动强度对湖泊营养状态呈显著的正影响,其表征指标人均GDP与建设用地所占流域面积比均具有较强的显著性,而在人类扰动较小的情况下,湖泊的营养状态与湖泊补给系数成正比,与湖泊蓄容量成反比,补给系数较小且其他因素也相同时,水体营养状态应与流域土壤本底值相关;以林、草地的面积比重所测度的流域自然生态系统发育程度与湖泊营养状态呈显著负相关关系,表明林地与草地生态系统对流域的氮、磷营养物的人湖量具有一定的削减作用,论文研究结果将为流域管理措施方案制订提供科技支撑。  相似文献   

20.
The nutrient enrichment of rivers and its consequences are among the most severe water quality problems in Europe, causing eutrophication and other problems. The decision-making processes involved in the management of these problems require extensive human expertise from people who deal directly with day-to-day stream problems, as well as empirical knowledge based on scientific research. This means that eutrophication is a complex problem, the optimal management of which requires an integrated and multidisciplinary approach. This approach can be taken using a Knowledge-Based System (KBS) built upon the concepts and methods of human reasoning. Accordingly, a KBS was developed within the STREAMES project. In this KBS most of the knowledge needed for managing eutrophication problems was organised and structured in the form of a decision tree (DT). The methodology specially developed to build this KBS, as well as the internal structure of the eutrophication decision tree, is presented here. The good DT obtained led to consider the KBS a suitable tool to support the management of eutrophication.  相似文献   

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