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松花江流域水生态环境质量评价研究   总被引:2,自引:1,他引:1  
采用生物完整性指数(IBI)法评价松花江流域的水生态环境质量。对25个候选生物参数进行敏感度分析、Pearson相关性分析,最终筛选出由总分类单元数、EPT分类单元数、EPT密度、敏感种分类单元比例、敏感物种数量、Hilsenhoff生物指数(HBI)6个核心参数构成的IBI评价指标。采用95%分位数法建立了IBI评价标准,将IBI评价结果划分为5个等级:大于35.84为优,26.88~35.84为良好,17.92~26.88为一般,8.96~17.92为较差,小于8.96为很差。结果表明,建立的IBI评价方法适用于松花江流域水生态环境质量评价,松花江流域各位点30.0%生物状况为优和良好,23.3%为一般;46.7%为较差和很差,说明流域内近一半区域的水生态质量存在不同程度的受损。流域生境质量主要处于一般-良好的状态;水质处于轻度污染。  相似文献
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利用2012年松花江流域生物、生境和水质的调查数据,采用生物完整性指数(IBI)评价松花江流域的水生态环境质量,并着重对IBI评价结果与生境质量、水质间的关系及生物与生境和化学参数间的相关关系进行了分析。结果表明,松花江流域IBI评价结果与其生境质量存在显著正相关,与水质评价结果基本一致。生境质量及大多数生境参数均与多项生物参数间存在显著/极显著的相关关系;其次,COD、CODMn、BOD5、TN、TP等超标化学因子也与多项生物参数存在显著/极显著的相关关系,说明生境受损和有机污染压力是引起松花江流域水生态环境质量变化的主要压力。为恢复和改善松花江流域的水生态质量,研究建议针对流域生境质量和超标化学污染开展相应的保护和控制措施。  相似文献
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The extent of degradation of benthic communities of the Chesapeake Bay was determined by applying a previously developed benthic index of biotic integrity at three spatial scales. Allocation of sampling was probability-based allowing areal estimates of degradation with known confidence intervals. The three spatial scales were: (1) the tidal Chesapeake Bay; (2) the Elizabeth River watershed; and (3) two small tidal creeks within the Southern Branch of the Elizabeth River that are part of a sediment contaminant remediation effort. The areas covered varied from 10–1 to 104 km2 and all were sampled in 1999. The Chesapeake Bay was divided into ten strata, the Elizabeth River into five strata and each of the two tidal creeks was a single stratum. The determination of the number and size of strata was based upon consideration of both managerially useful units for restoration and limitations of funding. Within each stratum 25 random locations were sampled for benthic community condition. In 1999 the percent of the benthos with poor benthic community condition for the entire Chesapeake Bay was 47% and varied from 20% at the mouth of the Bay to 72% in the Potomac River. The estimated area of benthos with poor benthic community condition for the Elizabeth River was 64% and varied from 52–92%. Both small tidal creeks had estimates of 76% of poor benthic community condition. These kinds of estimates allow environmental managers to better direct restoration efforts and evaluate progress towards restoration. Patterns of benthic community condition at smaller spatial scales may not be correctly inferred from larger spatial scales. Comparisons of patterns in benthic community condition across spatial scales, and between combinations of strata, must be cautiously interpreted.  相似文献
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We developed an index to differentiate between low dissolved oxygen effects and sediment contamination effects for sites classified as degraded by the Chesapeake Bay Benthic Index of Biotic Integrity (B-IBI), using discriminant analysis. We tested 126 metrics for differences between sites with low dissolved oxygen and sites with contaminated sediments. A total of 16 benthic community metrics met the variable selection criteria and were used to develop a discriminant function that classified degraded sites into one of two stress groups. The resulting discriminant function correctly classified 77% of the low dissolved oxygen sites and 80% of the contaminated sites in the validation data.  相似文献
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The Chesapeake Bay benthic index of biotic integrity (B-IBI) was developed to assess benthic community health and environmental quality in Chesapeake Bay. The B-IBI provides Chesapeake Bay monitoring programs with a uniform tool with which to characterize bay-wide benthic community condition and assess the health of the Bay. A probability-based design permits unbiased annual estimates of areal degradation within the Chesapeake Bay and its tributaries with quantifiable precision. However, of greatest interest to managers is the identification of problem areas most in need of restoration. Here we apply the B-IBI to benthic data collected in the Bay since 1994 to assess benthic community degradation by Chesapeake Bay Program segment and water depth. We used a new B-IBI classification system that improves the reliability of the estimates of degradation. Estimates were produced for 67 Chesapeake Bay Program segments. Greatest degradation was found in areas that are known to experience hypoxia or show toxic contamination, such as the mesohaline portion of the Potomac River, the Patapsco River, and the Maryland mainstem. Logistic regression models revealed increased probability of degraded benthos with depth for the lower Potomac River, Patapsco River, Nanticoke River, lower York River, and the Maryland mainstem. Our assessment of degradation by segment and water depth provided greater resolution of relative condition than previously available, and helped define the extent of degradation in Chesapeake Bay.  相似文献
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