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1.
以锦州市大凌河流域为例,从耐受性、物种组成、丰富度、习性/食性等方面选择16个备选参数构建底栖动物完整性(B-IBI)评价体系,经SPSS统计分析精准识别流域水生态健康核心参数。结果表明:参照点位处于良好或优秀状态,其B-IBI指数位于2.31~3.62范围;受损河流点位大多处于欠佳状态,B-IBI指数位于0.12~2.70范围,很差和较差健康状态所占比例54.5%;阴离子表面活性剂、总磷、氨氮、BOD5、CODCr、溶解氧都与B-IBI值有关,水生态系统不健康主要与水体污染密切相关,河流水生昆虫类群等底栖动物易受周边高强度开发建设的影响。  相似文献   

2.
基于PSR模型的甘南尕海湿地生态系统健康评价   总被引:1,自引:0,他引:1  
[目的]对甘南尕海湿地生态系统健康进行综合评价,为该湿地科学管理和可持续发展提供科学依据。[方法]运用PSR数学模型,从压力、状态和响应3个方面选取18个评价指标来构建尕海湿地生态系统健康评价体系,并采用层次分析法(AHP)确定指标权重,分析生态系统健康指数。[结果]尕海湿地生态系统健康指数为0.588 1,属于亚健康状态;压力子系统健康指数为0.733 2,属于健康状态;状态和响应子系统健康指数为0.489 3和0.567 9,二者都属于亚健康状态。[结论]全球气候变化和人为活动干扰使尕海湿地生态系统健康状况受到严重威胁,迫切需要科学地保护和修复措施,提高湿地管理水平。  相似文献   

3.
根据2020年调查监测的浑河流域12个点位大型底栖动物类群数据,从功能摄食群、污染耐受情况、各类群相对丰度和分类单元情况上,以参照点位25%分位数值为标准利用大型底栖动物完整性评价浑河水生态健康状况。结果表明:参与评价的点位中达到健康状况的点位有2个,达到亚健康和一般健康的各4个,达到差和极差点位的各1个;受人为干扰浑河水系整体连通性稍差,生境类型和生态功能差异明显,各点位健康状态呈多样化发展。  相似文献   

4.
利用综合评价法和多指标评价体系,评价辽宁省重点河湖湿地生态系统健康状况.结果显示,大麦科湿地、三岔河湿地处于健康状态,仙子湖、卧龙湖、獾子洞和阜新阿尔乡湿地处于亚健康状态.针对各河湖湿地生态系统存在的主要问题提出行之有效的管理对策,旨在为河湖湿地生态保护提供一定的参考.  相似文献   

5.
结合栖息地质量指数方法对浑河流域水生态健康指标进行构建,并采用主成分分析方法对指标进行了筛选,结合构建的指标体系对流域内6个主要断面进行了评价。评价结果表明:浑河流域水生态健康影响的4个关键指标分别为电导率、BOD5、CODcr及HQI。浑河中游东陵段由于处于城市段,其栖息地质量指数较低;上游清原及大伙房水库水源保护段,栖息地质量指数偏高。浑河总体水生态系统处于亚健康状态,部分区域处于较差状态。  相似文献   

6.
根据生态交错带变化对周围环境变化具有一定指示作用的原理,利用游动分割窗技术对宁夏盐池四儿滩湿地交错带进行判定,并结合样方植被调查、生物多样性指数、降雨量等因素分析了交错带变化情况。结果表明,游动分割窗技术适用于四儿滩湿地交错带判定,适宜窗口宽度为8个样方;2006—2013年的交错带判定结果发现,2007年湿地宽度最大,距湿地中心距离最远,健康状况最好。之后几年各项指数呈逐年下降趋势,湿地健康状况逐年变差,其变差的原因是2008年高铁建设截断了湿地上游水源补给。因此,在注重经济发展的同时,要尽量少破坏地表径流系统,以利于湿地长远发展。研究表明,在西北半干旱区湿地健康评价和退化研究中,通过交错带的变化来反映整个湿地生态系统健康状况是一种可行的思路和方法。  相似文献   

7.
基于PSR模型的七里海湿地生态脆弱性评价研究   总被引:2,自引:0,他引:2  
利用"3S"技术,结合景观生态学、生态健康学及水文地质学理论,选用压力—状态—响应评价模型,选取人口密度、人类干扰指数、初级生产力、分维数、破碎度、斑块形状指数、湿地弹性度指数、湿地服务功能、湿地变化面积等9个评价指标,以200 m×200 m栅格点状单元为基本单元,分析评价七里海湿地的生态环境脆弱性状况。研究结果为:七里海湿地中度脆弱区面积最大,约为28.85 km2,占湿地总面积的30.37%;其次是一般脆弱区,面积约为21.68 km2,占22.82%;再次是重度脆弱区,面积约为20.17 km2,占21.23%;最后是轻度脆弱区和潜在脆弱区,面积分别为16.36 km2和7.94 km2,占17.22%和8.36%。  相似文献   

8.
以黄骅湿地为例,在RS和GIS技术支撑下分析了湿地1987~2003年16a间景观类型间的变化情况,并通过生态环境指数、区域土地利用转变类型生态贡献率评价了景观类型间的转变对生态环境带来的影响.结果表明,黄骅湿地生态环境受到破坏,生态质量下降,其生态环境指数由1987年的0.492变为2003年的0.422;湿地处于退化状态,应加强对湿地的保护.  相似文献   

9.
闽江大樟溪下游沿线湿地沉积物中重金属   总被引:1,自引:0,他引:1  
基于2018年7月采集的大樟溪下游沿线湿地表层沉积物样品,探讨了6种重金属(Pb、Cr、Cu、Zn、Ni、Cd)的沿程分布特征,并运用地累积指数法(Igeo)和潜在生态风险指数法(RI)对其生态风险进行了评估。结果表明,湿地沉积物中重金属的平均含量整体表现为Zn>Pb>Cr>Cu>Ni>Cd,且其沿程变化较为一致,而这主要取决于沉积物粒度组成、磁学参数、pH、EC和有机质的沿程分布。湿地沉积物中的6种重金属含量均于桃花洲、耕櫵亭、方庄村和奥莱时代出现较低值,原因主要与4个采样点的采砂活动改变了河流水沙条件使得沉积物发生粗化有关。湿地沉积物中6种重金属之间均存在极显著正相关关系(P<0.01),说明其具有同源性,并可能代表了一个因采砂/采石活动以及建筑/生活垃圾堆放导致的复合污染源。大樟溪下游沿线湿地大部分样点的Pb处于轻度污染状态,而Cd处于中度污染状态。6种重金属平均单项潜在生态风险指数(E■)表现为Cd>Pb>Ni>Cu>Cr>Zn,Cd具有强生态风险。所有样点重金属的平均RI值为228.62,说明湿地整体处于中等生态风险。研究发现,尽管大樟溪下游沿线湿地沉积物中的重金属含量相比闽江上游其它支流和闽江中下游河段处于一个较低水平,但其Pb、Cd污染及生态风险(特别是Cd)仍较为突出,故下一步在加强对沿线湿地管控时应给予特别重视。  相似文献   

10.
基于2018年7月采集的大樟溪下游沿线湿地表层沉积物样品,探讨了6种重金属(Pb、Cr、Cu、Zn、Ni、Cd)的沿程分布特征,并运用地累积指数法(I_(geo))和潜在生态风险指数法(RI)对其生态风险进行了评估。结果表明,湿地沉积物中重金属的平均含量整体表现为ZnPbCrCuNiCd,且其沿程变化较为一致,而这主要取决于沉积物粒度组成、磁学参数、pH、EC和有机质的沿程分布。湿地沉积物中的6种重金属含量均于桃花洲、耕櫵亭、方庄村和奥莱时代出现较低值,原因主要与4个采样点的采砂活动改变了河流水沙条件使得沉积物发生粗化有关。湿地沉积物中6种重金属之间均存在极显著正相关关系(P0.01),说明其具有同源性,并可能代表了一个因采砂/采石活动以及建筑/生活垃圾堆放导致的复合污染源。大樟溪下游沿线湿地大部分样点的Pb处于轻度污染状态,而Cd处于中度污染状态。6种重金属平均单项潜在生态风险指数(E■)表现为CdPbNiCuCrZn,Cd具有强生态风险。所有样点重金属的平均RI值为228.62,说明湿地整体处于中等生态风险。研究发现,尽管大樟溪下游沿线湿地沉积物中的重金属含量相比闽江上游其它支流和闽江中下游河段处于一个较低水平,但其Pb、Cd污染及生态风险(特别是Cd)仍较为突出,故下一步在加强对沿线湿地管控时应给予特别重视。  相似文献   

11.
白洋淀柱状沉积物磷形态及其分布特征研究   总被引:1,自引:0,他引:1  
应用淡水沉积物磷形态的标准测试方法(SMT),调查了白洋淀6个典型湖区柱状沉积物中的磷形态分布、垂向及在两种沉积物粒级(砂土和粉砂/粘土)上的变化特征,分析了各形态磷之间的相关性。结果表明,白洋淀各湖区柱状沉积物总磷(TP)的平均含量为531~1223mg.kg-1DW,无机磷(IP)是白洋淀沉积物中磷的主要成分,占TP的72~83。湖区水体的污染及富营养化程度影响着生物可利用的铁/铝结合态磷(Fe/Al-P)在白洋淀不同湖区沉积物中的分布,从各形态磷含量和百分含量的变化幅度来看,均是Fe/Al-P〉有机磷(OP)〉钙结合态磷(Ca-P)。在垂向分布和两种粒级沉积物颗粒上,白洋淀沉积物各形态磷都有一定的变化规律,但不同磷形态的变化趋势不同,差异性也不一致。各形态磷相关性分析表明,在平均含量、垂向及粒级分布上,IP和Ca-P之间呈较好相关性,说明稳定的Ca-P是IP的主体;而在平均含量和垂向分布上,TP与IP和Ca-P之间都存在着较好的相关性,说明沉积物中TP的含量主要来自IP中的Ca-P。研究结果对于探讨白洋淀水污染沉积历史及内源磷释放对水体富营养化的贡献具有重要意义。  相似文献   

12.
2010年在枯水期、平水期、丰水期对洞庭湖的7个典型断面进行了大型底栖无脊椎动物采样,共获得底栖动物40种,其中节肢动物16种、软体动物18种,环节动物6种。根据Shannon-Wiener物种多样性指数确定了4个相对清洁的断面和3个污染断面,然后进行23种生物指数的综合评估,结果表明,(甲壳动物+软体动物)分类单元数、Shannon-Wiener物种多样性指数与Goodnight-Whitley指数3个底栖动物生物指数可以用作辨别洞庭湖典型断面水质的敏感生物指数。通过5、3、1记分法对3种生物指数统一量纲后,获得变化范围为3~15的综合生物指数,运用四分法划分出洞庭湖典型断面水质辨别的生物基准:3~6,差;7~9,一般;10~12,好;13~15,很好。据此对7个断面进行重新记分,获得了洞庭湖典型断面水质的基本分区现状:虞公庙、万子湖、目平湖3个断面的水质良好,而鹿角、坡头、南嘴及东洞庭湖4个断面的水质较差。该水质生物学基准基本适合评价洞庭湖典型断面的水质状况。  相似文献   

13.
We conducted a field survey in Japanese streams and rivers to generate useful information about whether the Japanese water quality standard for zinc (Zn) in the freshwater environment (30 μg/L) is over- or underprotective of the populations and communities of lotic benthic macroinvertebrates. Many macroinvertebrate populations were reduced and community characteristics were altered at two polluted sites with Zn concentrations above 1,000 μg/L as compared with control sites with Zn concentrations below 30 μg/L. In contrast, at least one site among three polluted sites with Zn concentrations of 80–126 μg/L experienced noncritical effects (i.e., no significant difference was observed between the sample mean at a polluted site and that at the control sites, and the sample mean was within the minimum–maximum range of those at the control sites) for most of the ten community metrics for diversity and abundance. In addition, the abundances of 95% of the dominant taxa were not always significantly lower at more than one polluted site (Zn concentrations, ≥80 μg/L). Our results suggest that Zn concentrations below approximately 100 μg/L are likely to protect most aspects of richness and abundance of the riverine macroinvertebrate communities in the study areas. This study shows a case that the Japanese Zn standard is likely overprotective of the macroinvertebrate populations and communities.  相似文献   

14.
Many studies have been carried out to investigate the wide scale problem of forest decline that is affecting vast numbers of trees throughout Europe and North American. Evidence of nutritional disturbances, both above- and below-ground, has been found for a variety of species. Furthermore, it has been suggested that differences in above-ground tree health are often reflected below ground, particularly in the root systems of declining trees. An investigation of root vitality, soil and leaf chemistry of healthy and unhealthy beech (Fagus sylvatica L.) was carried out at a number of sites in southern Britain, covering a range of different soil types. At each site, healthy and unhealthy trees growing in very close proximity were compared in order to avoid large scale environmental differences that might be expected when comparing stands of trees at different locations. Healthy trees were found to have significantly greater proportions of live mycorrhizal roots than their unhealthy neighbours at most of the sites investigated. In addition, significant differences in soil chemistry were found between trees in contrasting health, with healthy trees generally growing in soil containing higher concentrations of calcium, magnesium and potassium and lower aluminium/calcium ratios. Very few differences were found in leaf nutrient content, suggesting that soil chemistry is not yet limiting nutrient uptake. The importance of root system differences in the tolerance of unfavourable edaphic and climatic conditions is discussed with respect to tree health.  相似文献   

15.
胡维  葛刚  熊勇  吴兰 《农业环境保护》2012,(9):1785-1790
通过研究鄱阳湖南矶山湿地土壤在不同季节、不同植被类型和不同土壤深度下总有机碳、总氮、总磷的含量变化,分析了鄱阳湖南矶山湿地土壤养分的空间分布特征和季节变化规律。结果表明:南矶山湿地土壤总有机碳、总氮、总磷含量在不同的土壤深度、季节和植被类型中均表现出极显著差异。其中南矶山灰化苔草、南荻、狗牙根植被群落样地0~15cm表层土壤总有机碳、总氮含量显著大于30~45cm底层含量;灰化苔草、南荻群落土壤总有机碳和总氮含量的季节变化明显,尤其是表层土壤在各个不同的季节差异显著,但狗牙根植被群落土壤总有机碳和总氮含量季节变化不明显;3种典型植被类型下土壤总磷含量季节变化明显,呈现"N"的变化趋势。土壤总有机碳与总氮含量极显著正相关、与总磷含量显著相关,表明鄱阳湖南矶山湿地土壤氮、磷主要以有机质的结合形态存在。  相似文献   

16.
沉积物重金属污染是水环境污染评价的重要内容,重金属含量水平常被作为水环境质量的重要指标之一。为了掌握华北平原的府河和白洋淀中沉积物重金属的污染水平,研究了19个沉积物样品和3个土壤样品中7种重金属的污染特征,利用地积累指数法、潜在生态危害指数法及生物效应浓度法评估了重金属的环境风险,并初步分析了污染来源。结果表明,府河和白洋淀沉积物受多种重金属复合污染,其中Zn、Pb、Cu和Cd污染较为严重,府河沉积物的潜在生态环境危害强于白洋淀。相关分析显示府河和白洋淀重金属污染具有相似污染源,保定市工业废水、生活污水及府河沿岸金属冶炼企业很可能是白洋淀地区重金属的主要来源。从城市环境管理、生态环境修复、宣传教育等方面提出白洋淀区域重金属污染控制对策与建议,为白洋淀区域生态环境保护提供科技支撑。  相似文献   

17.
Benthic macroinvertebrate communities in 13 acidified South Swedish streams were sampled in 1981. The same localities were revisited in 1994 when most of the streams had been limed. Untreated streams were used as references. Species richness and proportion of predators increased between the two years. The differences are probably due to the warm and dry summer in 1994. However, the proportions of acid-sensitive species in various groups of streams were about the same the two years, indicating that liming had an insignificant effect on the return of these species. The resilience of the bottom fauna may be attributable to biotic conditions or the failure of the practiced liming methods to maintain healthy chemical conditions.  相似文献   

18.
We examined aquatic macroinvertebrate assemblages in six Arkansas low-order streams across three ecoregions. Samples were taken at locations above and below silviculture sites using Best Management Practices (BMPs) and were compared in winter and spring for 1 year prior to logging and 2 years after treatments. Implementation at all sites scored between 89 and 100% in compliance assessments using state BMP guidelines. Deficiencies were generally limited to engineering controls designed to prevent soil erosion; however, no clear evidence of sedimentation was observed in any of the study streams. Water quality variables were similar between sites upstream and downstream of the harvests in all survey periods. Analysis of variance did not indicate reduced taxonomic richness that could clearly be attributed to silviculture operations, but did reveal several significant differences in relative abundance variables that could be associated with negative impacts, primarily at a single site. Euclidean distance indicated that macroinvertebrate assemblage similarity between reference and treatment stations decreased after treatments at two additional study sites. At most sites, however, there was not an assemblage shift from organisms using coarse particulate organic matter as the primary food source to those using fine particulate organic matter downstream of the harvests. Our results indicated that BMPs were moderately to strongly effective in protecting water quality and biological integrity in five of the six study streams.  相似文献   

19.
Physicochemical parameters and benthic macroinvertebrate community structure were studied in a small valley stream in southwestern Pennsylvania. Sampling stations were located upstream and downstream of coal mine drainage input. Due to an alkaline discharge and significant downstream alkalinity the pH below the mine effluent remained between 5.8 and 7.0 throughout the course of this 18 mo study. The major factor affecting the benthic community seemed to be ferric hydroxide deposition. Certain taxa (Plecoptera and Ephemeroptera) were abundant at station sites above the mine discharge, while only those taxa tolerant of polluted conditions, such as Chironomidae and Tubifex, were prevalent at the downstream station sites. An analysis of benthic populations through changes in total numbers, species diversity, and species indicator organisms graphically demonstrated environmental stress within this aquatic ecosystem.  相似文献   

20.
土壤活性有机碳、氮是土壤有机碳、氮中最活跃的组分,在土壤碳、氮循环过程中具有重要作用。以湖南3个长期定位试验点(桃源、宁乡、桃江)为研究对象,分析测定表层土壤MBC、MBN、DOC、DON,研究长期施肥对土壤活性有机碳、氮(MBC+DOC,MBN+DON)的影响。结果表明,长期施用化肥及配施有机肥均能提高土壤活性有机碳、氮的含量。与对应的无肥处理(CK)相比,长期单施化肥(NPK)使土壤活性有机碳、氮的提高幅度分别为3.3%~21.0%和3.3%~27.1%,长期有机肥施用提高幅度分别为48.7%~84.8%和17.9%~105.8%,且土壤活性有机碳、氮含量随有机肥施用量的提高而增加,3个试验点活性有机碳大小顺序为桃源〉宁乡〉桃江。土壤活性有机碳与土壤有机碳(SOC)的累积速率呈显著正相关关系(P〈0.05),而与SOC的含量关系不大。桃源土壤粘粒含量较高可能是土壤SOC累积速率快的主要原因;宁乡和桃江的粘粒含量和有机碳投入量相差不大,桃江较高的初始SOC水平影响了SOC积累速率;桃源和宁乡试验点的土壤活性氮含量相差不大,约是桃江的1.8倍。与土壤全氮(TN)相比,全氮的积累速率与土壤活性氮的关系更为密切,两者间有极显著的相关关系(P〈0.01)。  相似文献   

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