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1.
源头区溪流是河流生态系统最脆弱的部分,也是淡水底栖大型无脊椎动物(简称底栖动物)集中分布的热点区域,在流域物种库的形成和生态系统的多样性维持过程中具有不可忽视的作用。然而,目前国内对源头区溪流底栖动物多样性的系统调查研究较少。笔者对位于浙江省丽水市瓯江源头区的龙泉溪进行了底栖动物多样性调查研究,分别于2021年丰水期和平水期在覆盖龙泉溪主要山溪河流的18个样点采样,共采集获得底栖动物标本3 700余号。通过联合使用传统形态分类和DNA条形码技术,共鉴定出底栖动物165种,隶属5门、9纲、19目、68科、124属。联合使用DNA条形码可使底栖动物科、种水平的分辨力提升28.3%和34.1%。调查研究表明:龙泉溪底栖动物多样性丰富,物种组成以节肢动物为主(占比高达87.9%,145种),其中水生昆虫占绝大多数(共计8目、48科、140种,占84.8%),主要优势种为鞘翅目的狭溪泥甲属1种Stenelmis sp.1、毛翅目的纹石蛾属Hydorpsyche和短脉纹石蛾属Cheumatopsyche各1种;底栖动物群落多样性丰富,且在丰水期和平水期均维持在较高的水平;海拔和底质类型等微生境条件对底栖动物多样性分布的影响分析显示,底质类型对底栖动物分布密度的影响显著。对水生态状况的生物评估结果显示:Biotic Index污染生物指数更适合龙泉溪流域的水质健康状况评估,龙泉溪流域整体的水生态状况健康,水质属清洁或极清洁。该研究使用传统形态学和DNA条形码技术相结合的鉴定方式,提高了底栖动物物种鉴定的精度,所获得的多样性调查和水质评价结果为瓯江源头区溪流乃至整个流域的生态保护和长期监测提供了本底基础资料。  相似文献   

2.
滦河流域大型底栖动物生物完整性指数健康评价   总被引:1,自引:1,他引:1  
生物完整性指数能够综合反映河流健康状况,是管理者制定科学保护恢复策略的有效评价工具。为全面了解滦河流域水生态健康状况,于2016年10—11月在滦河流域布设53个采样点,同时监测环境数据和大型底栖动物物种数据。通过构建底栖动物生物完整性指数(B-IBI)体系,对53个采样点进行生物完整性健康评价。B-IBI计算结果显示,滦河流域53个采样点中,"健康"和"亚健康"等级共有24个,"一般"等级有12个,"差"等级有10个,"极差"等级有7个。"健康"和"亚健康"的采样点多分布在承德市上游和冀东地区的部分干流和支流,而中下游大部分采样点表现为"差"和"极差"的健康状况。非参数检验结果显示,参照点B-IBI要显著高于受损点,表明所构建的B-IBI评价体系适用于在滦河流域开展河流健康评价。  相似文献   

3.
研究以成都市域内河流为研究对象,通过采样分析得到水质、生境状况、浮游藻类、底栖动物等相关指标,利用综合指标体系法,评价成都市域内河流生态系统健康状况,并结合成都市人口、土地利用、地区生产总值等因素分析人类活动与河流生态健康的关系。结果表明:成都市河流浮游藻类以硅藻和绿藻为主,部分中下游采样点出现以蓝藻为主的情况;底栖动物以指示有机污染的颤蚓科出现的频率最高,约48%的采样点以颤蚓科为优势种;约74%的河流生态健康状况为"差"或"很差",河流生态健康状况整体呈现中上游优于下游、城市周边优于市区的特征;人口密度、人类活动用地比例与河流中氨氮呈显著正相关,人类活动会显著影响河流生态系统健康。  相似文献   

4.
Two social impact assessment (SIA) studies of Central Queensland's Coppabella coal mine were undertaken in 2002–2003 and 2006–2007. As ex post studies of actual change, these provide a reference point for predictive assessments of proposed resource extraction projects at other sites, while the longitudinal element added by the second study illustrates how impacts associated with one mine may vary over time due to changing economic and social conditions. It was found that the traditional coupling of local economic vitality and community development to the life cycle of resource projects—the resource community cycle—was mediated by labour recruitment and social infrastructure policies that reduced the emphasis on localised employment and investment strategies, and by the cumulative impacts of multiple mining projects within relative proximity to each other. The resource community cycle was accelerated and local communities forced to consider ways of attracting secondary investment and/or alternative industries early in the operational life of the Coppabella mine in order to secure significant economic benefits and to guard against the erosion of social capital and the ability to cope with future downturns in the mining sector.  相似文献   

5.
The Second Songhua River was subjected to a large amount of raw or primary effluent from chemical industries in Jilin city in 1960s to 1970s, resulting in serious mercury pollution. However, an understanding of other trace metal pollution has remained unclear. The objective of this study was to investigate trace metal contamination in the sediment of the river. Bottom sediment samples were taken in the river between Jilin city and Haerbin city in 2005. An uncontaminated sediment profile was taken in the Nen River at the same time. Total concentrations of Al, Fe, Mg, Ca, K, Na, Ti, Mn, V, Sc, Co, Cu, Cr, Ni, Pb and Zn in the sediment samples were measured by ICP-MS or ICP-OES, following digestion with various acids. Concentrations of Co, Cu, Cr, Ni, Pb and Zn in the surface sediments were 5.1–14.7, 18.5–78.9, 2.4–75.4, 7.2–29.0, 13.5–124.4, and 21.8–403.1 mg/kg, respectively, generally decreasing along the course of the river from Jilin city to Haerbin city. Background concentrations of trace metals were reconstructed by geochemical normalization to a conservative element scandium. Results showed that concentrations of Co, Cr, and Ni in the sediment were generally only slightly higher than or equal to their background values, while concentrations of Cu, Pb, and Zn in the some sediment samples were significantly higher than their background values. In detail, the sediment at Jilin city was moderately contaminated by Cu, and the sediment of the Second Songhua River was moderately contaminated by Pb and Zn. The top layer (0–10 cm depth) and bottom layers (30–46 cm depth) of one sediment profile at Wukeshu town were generally moderately polluted by Pb and Zn. Synthetically, the surface sediment in the studied river section was classified as natural sediment without ecological risk by the sediment pollution index (SPI) of Cu, Cr, Ni, Pb and Zn. Only the 30–45 cm depth of the sediment profile at Wukeshu town was classified as low polluted sediment by the SPI of these metals, recording a historical contamination of the river in the 1960s to 1970s. This buried contamination of trace metals might pose a potential risk to water column under disturbance of sediment. Foundation item: The National Basic Research Priorities Program of China (2004CB418502)  相似文献   

6.
Pipeline crossing construction alters river and stream channels, hence may have detrimental effects on aquatic ecosystems. This review examines the effects of crossing construction on fish and fish habitat in rivers and streams, and recommends an approach to monitoring and assessment of impacts associated with these activities. Pipeline crossing construction is shown to not only compromise the integrity of the physical and chemical nature of fish habitat, but also to affect biological habitat (e.g., benthic invertebrates and invertebrate drift), and fish behavior and physiology. Indicators of effect include: water quality (total suspended solids TSS), physical habitat (substrate particle size, channel morphology), benthic invertebrate community structure and drift (abundance, species composition, diversity, standing crop), and fish behavior and physiology (hierarchy, feeding, respiration rate, loss of equilibrium, blood hematocrit and leukocrit levels, heart rate and stroke volume). The Before-After-Control-Impact (BACI) approach, which is often applied in Environmental Effects Monitoring (EEM), is recommended as a basis for impact assessment, as is consideration of site-specific sensitivities, assessment of significance, and cumulative effects.  相似文献   

7.
底栖动物是水生态系统的重要组成部分,其群落特征通常用来评价水生态环境质量。研究了2012—2019年松花江干流水生态环境质量状况、变化趋势,并应用冗余分析(RDA)探究底栖动物群落结构特征与水环境因子之间的响应关系。结果表明:8年间共鉴定出底栖动物246个分类单元,隶属于4门、9纲、25目、58科、69属,其中水生昆虫的EPT物种为99个分类单元,占总物种数的40.24%;水生昆虫的其他物种为68个分类单元,占总物种数的27.64%;软体动物为36个分类单元,占总物种数的14.63%;环节动物为25个分类单元,占总物种数的10.16%;甲壳动物为18个分类单元,占总物种数的7.32%。底栖动物密度总体呈上升趋势,种类组成总体有所增多,其中环节动物、软体动物和甲壳动物有向水生昆虫转变的趋势,群落结构相对稳定且主要以水生昆虫占比最多,底栖动物密度平均值为5.97×103个/m2,变化范围为2.86×103~8.98×103个/m2,优势科(属)主要为小蜉属Ephemerella、小寡脉蜉属Oligoneuriella、扁蜉属Heptagenia、等蜉属Isonychia、纹石蛾科Hydropsychidae、缺叉多距石蛾属Polycentropus、摇蚊科Chironomidae和圆田螺属Cipangopaludina等。生物指数评价结果多数为"中等"及以上,评价结果趋于稳定,且下游评价结果好于上游。松花江干流的水环境质量变化阶段性明显,溶解氧含量升高,氨氮呈下降趋势,其余指标呈波动变化。冗余分析(RDA)结果表明:影响松花江干流底栖动物群落结构变化的主要环境因子是随时间推移而变化的,其中溶解氧、生化需氧量、化学需氧量、总磷、氨氮和总氮等指标是影响该监测区域底栖动物群落分布的重要环境因子。  相似文献   

8.
采用归一化植被指数、景观多样性指数、景观均匀度指数等技术指标,评价那棱格勒河下游绿洲的生态环境现状。结果表明:那棱格勒河下游绿洲区主要为中植被覆盖(覆盖度30%~60%)区域,占绿洲区总面积的42.83%;低植被覆盖类型(覆盖度10%~30%)和高植被覆盖类型(覆盖度60%)次之。极低植被覆盖(覆盖度10%)区域最少,占绿洲区总面积的3.96%。稀疏草地和荒漠为该区域的优势景观,自然生产力等级低,生态系统受外界干扰后难以恢复,极易发生退化与沙化,系统的恢复稳定性与阻抗稳定性都较弱。  相似文献   

9.
Samples of water, sediment and suspended particulates were collected from 13 sites in the middle and lower reaches of the Yellow River in China. Phthalic acid esters (PAEs) concentrations in different phases of each sample were determined by Gas Chromatogram GC-FID. The results are shown as follows: (1) In the Xiao Langdi–Dongming Bridge section, PAEs concentrations in water phase from the main river ranged from 3.99 × 10−3 to 45.45 × 10−3 mg/L, which were similar to those from other rivers in the world. The PAEs levels in the tributaries of the Yellow River were much higher than those of the main river. (2) In the studied branches, the concentration of PAEs in sediment for Luoyang Petrochemical Channel (331.70 mg/Kg) was the highest. The concentrations of PAEs in sediment phase of the main river were 30.52 to 85.16 mg/Kg, which were much higher than those from other rivers in the world. In the main river, the concentration level of PAEs on suspended solid phases reached 94.22 mg/Kg, and it reached 691.23 mg/Kg in the Yiluo River – one tributary of the Yellow River. (3) Whether in the sediment or on the suspended solid phases, there was no significant correlation between the contents of PAEs and TOC or particle size of the solid phase; and the calculated Koc of Di (2-Ethylhexyl) Phthalate (DEHP) in the river were much less than the theoretical value, which inferred that PAEs were not on the equilibrium between water and suspended solid phases/sediment. (4) Among the measured PAEs compounds, the proportions of DEHP and di-n-butyl phthalate (DBP) were much higher than the others. The concentrations of DEHP exceeded the Quality Standard in all the main river and tributary stations except those in the Mengjin and Jiaogong Bridge of the main river. This indicates that more attention should be paid to pollution control and further assessment in understanding risks associated with human health.  相似文献   

10.
水生态监测能够为水生态环境监督、管理和保护提供重要的数据和技术支撑。加强黄河水生态监测,维护流域水生态系统健康,对促进黄河流域高质量发展具有重要意义。从常规水质监测、生境监测和生物监测3个方面,分析了中国水生态监测方法的研究进展及在黄河流域的应用实践。结合黄河流域水生态监测尤其是生物监测相对滞后的现状,探讨了流域水生态监测的发展方向。建议加快黄河流域水生态监测能力建设,建立适用于黄河流域的水生态监测与评价标准体系,探索新兴监测技术与传统技术的有机结合。  相似文献   

11.
The Mid-Atlantic Highlands Assessment (MAHA) included the sampling of macroinvertebrates from 424 wadeable stream sites to determine status and trends, biological conditions, and water quality in first through third order streams in the Mid-Atlantic Highlands Region (MAHR) of the United States in 1993–1995. We identified reference and impaired sites using water chemistry and habitat criteria and evaluated a set of candidate macroinvertebrate metrics using a stepwise process. This process examined several metric characteristics, including ability of metrics to discriminate reference and impaired sites, relative scope of impairment, correlations with chemical and habitat indicators of stream disturbance, redundancy with other metrics, and within-year variability. Metrics that performed well were compared with metrics currently being used by three states in the region: Pennsylvania, Virginia, and West Virginia. Some of the metrics used by these states did not perform well when evaluated using regional data, while other metrics used by all three states in some form, specifically number of taxa, number of EPT taxa, and Hilsenhoff Biotic Index, performed well overall. Reasons for discrepancies between state and regional evaluations of metrics are explored. We also provide a set of metrics that, when used in combination, may provide a useful assessment of stream conditions in the MAHR.  相似文献   

12.
开展水生态环境质量评价方法研究,建立合适的河流健康评价体系是解决河流健康问题的前提和实现河流健康管理的重要手段。黄河自上而下生态环境现状迥异,水生态环境脆弱,寻求一种或多种适合黄河流域水生态环境质量的评价方法具有重要意义。该文介绍了国内外水生态环境质量评价方法及在黄河流域的应用进展,总结了鱼类生物完整性指数(F-IBI)、底栖无脊椎动物完整指数(B-IBI)、着生藻类生物完整性指数(P-IBI)及水生态环境质量综合评价法的主要指标,以及黄河流域不同区域生物种类的评价指标,分析了各评价方法优缺点及应用范围,并根据目前研究基础评述了黄河流域水生态环境质量评价存在的问题,对黄河流域水生态环境质量评价方法、指示生物的选择及水生态环境质量综合评价法的研究等提出了具体建议。  相似文献   

13.
为准确掌握涪江绵阳段表层沉积物重金属的污染特征,分析了7个监测断面表层沉积物中Cd、Se、Mn等19种重金属质量浓度,采用地累积指数法、潜在生态风险评价法和污染负荷指数法评估了沉积物重金属的污染程度及潜在风险。结果表明:涪江绵阳段表层沉积物中Se、Cd、Ba和Hg等元素含量显著超过其土壤背景值,重金属的污染程度依次为Se>Cd>Ba>Hg>Mo>Mn;潜在生态风险评价和污染负荷指数评价结果均显示,断面的污染程度排序为楼房沟>李家渡>福田坝>丰谷>涪江铁路桥>百顷>平武水文站断面。楼房沟断面沉积物微观形貌主要为片状或块状,物相主要为石英及少量白云母、方解石和菱锰矿等,与铅锌矿、电解锰渣等主要矿物组成相似,重金属主要来源为尾矿渣在河床的沉积及金属矿开采等外源输入。  相似文献   

14.
The distribution of trace metals in sediments of the lower reaches of the New Calabar River, Nigeria was evaluated togetherwith the partitioning of their chemical species between fivegeochemical phases. Samplings were made in five zones at the lower reaches of the New Calaber River. All the trace metals were determined by AAS after selective chemical extractions andconcentrations given in g gm-1 (dry weight basis). The average totalconcentrations found for trace metals in the sediment were (mean ± rsd.) Pb: 41.6 ± 0.29, Zn: 31.60 ± 0.42, Cd: 12.80 ± 0.92, Co: 92 ± 0.25, Cu: 25.5 ± 0.65 and Ni: 3.2 ± 0.25. Maxima and minima concentrations are inconsistent with previous studies in other rivers of this region. Spatial distribution revealed that the sources of trace metals into theriver appeared to be of non-point. Five contamination indices were applied in studying the partitioning of the trace metals inthe sediment. These indices provided bases for ascertaining the potential environmental risk of trace metals in the river system.The results denote high partition levels in the more mobile andmore dangerous phases.  相似文献   

15.
福建晋江水系浮游植物调查及水质状态的评价   总被引:4,自引:0,他引:4  
2003年2~12月对福建晋江水系15个采样点的浮游植物群落季节性变动的生态特征,进行了种类组成、种群数量、优势种、污染指示种、水质等项目的调查研究。经鉴定晋江水系浮游植物共7个门类,73属,170种。藻量年均值达193.5×103个/升,晋江水系的浮游植物以硅藻门的种类占优势,表明晋江水系属于β_中污水体。并以这些参数对晋江水系的水质污染加以评价。  相似文献   

16.
利用生物完整性指数评价河流健康状态,对于水环境管理决策具有重要的实践意义。基于大型底栖动物构建生物完整性指数(B-IBI),并评价松花江流域的水生态系统健康状况。在松花江主要干支流设定37个采样点,分别于2016年6、9月进行环境因子和大型底栖动物调查研究。最终从28个候选参数中确定了种类总数、摇蚊种类数、敏感种百分比、Hilsenhoff指数、Marglef指数作为核心参数构建B-IBI。通过0~10赋分法,计算得到了松花江流域全部采样点的生物完整性评价得分。结果显示,松花江流域内60%区域生物状态存在不同程度的损害。另外,B-IBI能够综合反映松花江大型底栖动物群落多样性、生境质量、理化水质等,具有一定的适用性。  相似文献   

17.
药品和个人护理品(PPCPs)作为一类新污染物,种类繁多,且广泛存在于自然水体中。长江流域下游地区由于人口稠密,产业发达,PPCPs对于水体的污染问题尤为突出。简述了2010—2021年长江流域下游水体中PPCPs的赋存状况、时空分布及溯源分析情况,并对PPCPs的生态环境风险评估研究进展进行总结,揭示了近10年来长江流域下游水体中PPCPs的污染状况及变化态势,提出了未来PPCPs监测、溯源和风险评估的发展趋势,以期为水环境中PPCPs污染物的预警和管控提供参考依据。  相似文献   

18.
A portion of Arizona’s San Pedro River is managed as a National Riparian Conservation Area but is potentially affected by ground-water withdrawals beyond the conservation area borders. We applied an assessment model to the Conservation Area as a basis for monitoring long-term changes in riparian ecosystem condition resulting from changes in river water availability, and collected multi-year data on a subset of the most sensitive bioindicators. The assessment model is based on nine vegetation bioindicators that are sensitive to changes in surface water or ground water. Site index scores allow for placement into one of three condition classes, each reflecting particular ranges for site hydrology and vegetation structure. We collected the bioindicator data at 26 sites distributed among 14 reaches that had similar stream flow hydrology (spatial flow intermittency) and geomorphology (channel sinuosity, flood-plain width). Overall, 39% of the riparian corridor fell within condition class 3 (the wettest condition), 55% in condition class 2, and 6% in the driest condition class. Condition class 3 reaches have high cover of herbaceous wetland plants (e.g., Juncus and Schoenoplectus spp.) along the perennial stream channel and dense, multi-aged Populus-Salix woodlands in the flood plain, sustained by shallow ground water in the stream alluvium. In condition class 2, intermittent stream flows result in low cover of streamside wetland herbs, but Populus-Salix remain abundant in the flood plain. Perennial wetland plants are absent from condition class 1, reflecting highly intermittent stream flows; the flood plain is vegetated by Tamarixa small tree that tolerates the deep and fluctuating ground water levels that typify this reach type. Abundance of herbaceous wetland plants and growth rate of Salix gooddingii varied between years with different stream flow rates, indicating utility of these measures for tracking short-term responses to hydrologic change. Repeat measurement of all bioindicators will indicate long-term trends in hydro-vegetational condition.  相似文献   

19.
为了明确三江源智慧生态畜牧业示范区内土壤重金属元素含量特征及潜在风险,2015年7月在三江源智慧生态畜牧业示范区11个示范村镇进行土壤样品采集,带回实验室分析Pb、Cd、Hg、Cr、Cu、Zn、Ni含量。对数据进行统计分析并采用内梅罗综合污染指数和生态危害指数进行风险等级评价。结果显示:部分采样点重金属元素含量高于青海省背景值;Pb、Cr、Cu、Zn、Ni主要受土壤母质的影响,Cd受自然和人为因素的双重影响,Hg主要受人为因素影响;内梅罗综合污染指数显示11个点位的指数都小于1,该地未出现污染状况;生态危害指数显示除GMY点位处于轻微风险等级,其余采样点为中等风险等级。总体上示范区内土壤未出现强污染和面源污染状况,但需要加强点源污染的风险防范。  相似文献   

20.
Using the Yellow River, China, the study explores the problem of the use of COD and BOD5 as water quality management parameters in the presence of very high levels of suspended sediment (TSS) that characterize this river. Although the amount of natural organic matter per unit of suspended sediment of the Yellow River is not high, the very high concentration of mineral sediment in the Yellow River results in a large concentration of organic matter, which artificially inflates the laboratory values of COD and, as a consequent, leads to greatly exaggerated reports of pollution of the Yellow River. BOD5 can more accurately reflect the pollution of the Yellow River than COD; however, measured values of BOD under-report the actual values due to settling of the sediment in the incubation chamber resulting in values that are 21.6--38.3% less than the actual values. Therefore corrections are required for laboratory COD and BOD values so that the values are not artifacts of the sediment regime. Our work provides new insight into this phenomenon and demonstrates how correction factors may be determined and used with pollution data. Our work also suggests that the actual pollution levels of the Yellow River are probably not as high as reported by monitoring agencies.  相似文献   

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