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21.
应用鱼类生物完整性指数评价荔浦河河流健康 总被引:2,自引:0,他引:2
生物完整性指数是河流生态系统健康评价主要方法之一。为评价荔浦河河流健康状况,选择鱼类作为指示生物,构建了基于鱼类生物完整性指标体系。2017年1月、4月、7月和10月对荔浦河4次采样共采集到鱼类21 192尾,经鉴定共计94种,隶属于6目17科62属。以S1(修仁镇)、S10(马岭镇)、S11(双江镇)作为参考点,经过分布范围分析、箱体图判别能力分析及相关性分析等指标筛选过程从25个候选指标筛选出5个指标,即鱼类总物种数、Shannon-Wiener多样性指数、肉食性鱼类数量百分比、敏感性鱼类数量百分比、产漂浮型卵鱼类数量百分比。将荔浦河河流健康等级分为"健康"、"一般"、"较差"、"极差"和"无鱼"5个等级。结果表明,荔浦河青山镇、荔浦县及蒲芦乡河段健康状态为"一般"水平,东昌镇、龙怀乡、杜莫镇及新坪镇河段健康状态为"较差"水平,茶城乡河段健康状态为"极差"水平。筑坝工程、架桥工程和修路工程等人类活动导致荔浦河支流上的健康状况比干流更差。上述研究结果可为荔浦河的河流管理和保护提供理论依据和技术支持。 相似文献
22.
对河流生态健康状况进行评价,可为河流治理和生态修复提供依据.基于2018年8—9月天津市河流现场调查获取的物理、化学和生物群落指标(浮游动物、浮游植物、底栖动物、鱼类、水生大型植物、陆生植物)数据,构建包含物理完整性、化学完整性和生物完整性在内的河流IEI(index of ecological integrity,生态完整性指数)评价体系,对天津市河流生态健康状况进行评价.根据生物栖息地评分和水质状况确定参照点位,采用标准化方法筛选候选指标,应用层次分析法计算三部分指标权重,最终得出天津市河流生态健康评价结果.结果表明:①IEI评价结果显示,天津市河流生态健康状况等级为“健康”的样点占18.8%,“较好”的样点占28.1%,“一般”的样点占40.6%,“较差”的样点占6.3%,“差”的样点占6.3%,天津市河流生态健康状况整体处于“一般”水平.②相关性分析表明,ρ(NH4+-N)和ρ(CODMn)超标是造成天津市水质达不到功能区标准的主要原因,同时也是影响河流生态健康的主要因素.研究显示,IEI评价法能够较为敏感地响应研究区面临的环境压力,适用于评价研究区河流生态健康. 相似文献
23.
Richard J. Horwitz Thomas E. Johnson Paul F. Overbeck T. Kevin O’Donnell W. Cully Hession Bernard W. Sweeney 《Journal of the American Water Resources Association》2008,44(3):724-741
Abstract: The joint influences of riparian vegetation and urbanization on fish assemblages were analyzed by depletion sampling in paired forested and nonforested reaches of 25 small streams along an urbanization gradient. Nonforested reaches were narrower than their forested counterparts, so densities based on surface area differ from linear densities (based on reach length). Linear densities (based on number or biomass of fish) of American eel, white sucker and tesselated darter, and the proportion of biomass of benthic invertivores were significantly higher in nonforested reaches, while linear densities of margined madtom and the number of pool species were significantly higher in forested reaches. Observed riparian effects may reflect differences in habitat and algal productivity between forested and nonforested reaches. These results suggest that relatively small‐scale riparian restoration projects can affect local geomorphology and the abundance of fish. Dense vegetative cover in riparian zones and similar or analogous habitats in both forested and nonforested reaches, the relatively small scale of the nonforested reaches, and the low statistical power to detect differences in abundance of rare species may have limited the observed differences between forested and nonforested reaches. There was a strong urbanization gradient, with reductions of intolerant species and increases of tolerant species and omnivores with increasing urbanization. Interactions between riparian vegetation type and urbanization were found for blacknose dace, creek chub, tesselated darter, and the proportion of biomass of lithophilic spawners. The study did not provide consistent support for the hypotheses that responses of fish to riparian vegetation would be overwhelmed by urban degradation or insignificant at low urbanization. 相似文献
24.
针对目前国内外尚无明确的气井完整性概念和生产气井完整性评价指标体系的现状,分析了现有的关于气井完整性解释的不足,初步提出了气井完整性的概念,强调了气井完整性是气井处于地层流体发生无控制流动的风险在可接受范围之内的状态。并根据此概念,从完整性管理、屏障设备、监测状态三个方面,建立了气井完整性评价指标体系,分析了各个评价指标与气井完整性的关系。屏障设备完整性是气井完整性的核心,完整性管理是提高气井完整性的关键,监测状态是气井完整性最直接的判断依据。 相似文献
25.
Using environmental stressor information to predict the ecological status of Maryland non-tidal streams as measured by biological indicators 总被引:4,自引:0,他引:4
Vølstad JH Roth NE Mercurio G Southerland MT Strebel DE 《Environmental monitoring and assessment》2003,84(3):219-242
In Maryland, U.S., an interim framework has recentlybeen developed for using biologically based thresholds, or `biocriteria', to assess the health of nontidal streams statewide at watershed scales. The evaluation of impairment is based on indices of biological integrity from the Maryland Biological Stream Survey (MBSS). We applied logistic regression to quantify how the biotic integrity of streams at a local scale is affected by cumulative effects resulting from catchment land uses, point sources, and nearby transmission line rights-of-way. Indicators for land use were developed from the remote sensing National Land Cover Data and applied at different scales. We determined that the risk of local impairment in nontidal streams rapidly increases with increased urban land use in the catchment area. The average likelihood of failing biocriteria doubled with every 10% points increment in urban land, thus an increase in urban land use from 0 to 20% quadruples the risk of impairment. For the basins evaluated in this study, catchments with more than 40–50% urban land use had greater than 80% probability of failing biocriteria, on average. Inclusion of rights-of-way and point sources in the model did not significantly improve the fit for this data set, most likely because of their low numbers. The overall results indicate that our predictive modeling approach can help pinpoint stream ecosystems experiencing or vulnerable to degradation. 相似文献
26.
依据2017年5、7、9月对三江平原19处沼泽湿地(参照湿地6处,受损湿地13处)的水生无脊椎动物采样结果,应用生物完整性理论和方法,构建水生无脊椎动物完整性指数,评价三江平原沼泽湿地健康状况。通过对27个候选指标的分布范围、判别能力和相关性分析,筛选出总分类单元数、扁卷螺科百分比、龙虱科百分比、刮食者百分比4个指标构成水生无脊椎动物完整性指数核心指标。采用比值法计算各指标参数值,将各参数值加和得到水生无脊椎动物完整性指数值。根据参照湿地水生无脊椎动物完整性指数值的25%分位数值确定评价标准,对小于25%分位数的值进行三等分,确定三江平原沼泽湿地健康评价标准:≥2.58,无干扰;1.72~2.58,轻度干扰;0.86~1.72,中度干扰;0~0.86,重度干扰。结果表明:所调查的三江平原沼泽湿地有78.95%受到不同程度的干扰(其中47.37%受到了中重度干扰),21.05%属于无干扰。 相似文献
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29.
Robert M. Hughes 《Environmental management》1985,9(3):253-262
Impacts of sediments and heavy metals on the biota of streams in the copper-mining district of southwestern Montana were examined by comparing aquatic communities of impacted streams with those of control streams. Control streams were chosen through the use of a technique that identifies similar streams based on similarities in their watershed characteristics. Significant differences between impacted and control sites existed for surface substrate, riparian vegetation, and the number of macroinvertebrate taxa. These results revealed that: (a) chemical and physical habitats at the impacted sites were disrupted, (b) the presence of trout was an inadequate measure of ecological integrity for these sites, and (c) watershed classification based on a combination of mapped terrestrial characteristics provided a reasonable method to select control sites where potential control sites upstream and downstream were unsuitable. 相似文献
30.
自然保护事业已经进入人与自然和谐的综合保护阶段,突破传统生物群落保护的要素式思维,从生态特征、生态系统健康和自组织能力等视角系统实施生态系统完整性保护,已基本成为共识。中国经历了长期部门化割裂管理,在国家公园体制建设过程中开始由分散走向统一,要求将山水林田湖草作为生命共同体进行生态系统完整性保护。基于集合种群等空间生态学理论,提出国家公园生态系统完整性不仅意味着内部自然空间的完整,更需着眼国家生态安全的大局和自然保护地体系的战略布局。国家公园只有成为生态地理区的节点并辐射周边区域,有效平衡行政区域之间以及人与自然之间的关系,才能真正实现完整生态系统的长效保护。目前,国内既有研究在指导全域布局和平衡人地关系方面仍考虑不足,试点过程中还存在管理型技术方法欠缺、空间边界受限于行政边界、未能从全局着眼构建以国家公园为核心的生态系统完整性网络、未充分考虑差异化的人地关系等问题。未来需要着眼大局,有效平衡国家公园及其周边区域的关系、不同行政区域之间的关系、国家公园人与自然的关系,从而实现生态系统完整性的长效保护。 相似文献