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1.
In Spain, a national project known as GUADALMED, focusing on Mediterranean streams, has been carried out from 1998 to 2005 to implement the European water framework directive (WFD) requirements. One of the main objectives of the second phase of the project (2002–2005) was to develop a predictive system for the Spanish Mediterranean aquatic macroinvertebrate communities. A combined-season (spring, summer, and autumn) predictive model was developed by using the latest improvements on the selection of best predictor variables. Overall model performance measures were used to select the best discriminant function (DF) models, and also to evaluate their biases and precision. The final predictive model was based on the best five DF models. Each one of these models involved eight environmental variables. Final observed (O), expected (E), and O/E values for the number of macroinvertebrate families (NFAM) and two biotic indices (IBMWP and IASPT) were calculated by averaging their values, previously weighted by the quality of each DF model. Regression analyses among the final O and E values for the calibration dataset showed a high proximity to the ideal theoretical model, where the final E values explained 73–84% of the variation present in the macroinvertebrate communities of the Spanish Mediterranean watercourses. The ANOVA performed among the reference (calibration and validation) and test datasets showed clear differences for the O/E values. Finally, the assessments carried out by the predictive model were sensitive to anthropogenic pressure present in the study area and allowed the definition of five ecological status classes according to the WFD requirements. Handling editor: Richard H. Norris  相似文献   

2.
SUMMARY 1. In Europe, water policy is currently undergoing considerable change as emphasised by the recent European Water Framework Directive (WFD), which requires the restoration and maintenance of 'healthy' aquatic ecosystems by the assessment of their hydromorphological, chemical and biological characteristics. If the requirements of the WFD are to be met, effective biological tools are needed to measure the 'health' of rivers at scales large enough to be useful for management. These tools need to be ecologically based, efficient, rapid and applicable in different ecological regions. Among potential indicators, fish assemblages are of particular interest because of their ability to integrate environmental variability at different spatial scales. To meet the goals of the WFD, the French Water Agencies and the Ministry of the Environment initiated a research programme to develop a fish-based index that would be applicable nationwide.
2. A variety of metrics based on occurrence and abundance data and reflecting different aspects of the fish assemblage structure and function were selected from available literature and for their potential to indicate degradation.
3. Logistic and multiple linear regression procedures were applied, using an initial data set of 650 reference sites fairly evenly distributed across French rivers and defined by some easily measured regional and local characteristics, to elaborate the simplest possible response model that adequately explained the observed patterns of each metric for a given site.
4. Models obtained for each metric were validated using two independent data sets of 88 reference sites and 88 disturbed sites. These procedures allowed us to select the most effective metrics in discriminating between reference and disturbed sites.  相似文献   

3.
Littoral cartography is a valuable tool which uses shallow water macroalgal communities for monitoring ecosystem health and water quality. Cartography of littoral rocky-shore communities (CARLIT) is a European Union Water Framework Directive-compliant monitoring method widely used in the Western Mediterranean Sea. This non-destructive method is based on a visual observation of the type and length of coast occupied by rocky-shore communities in the upper-sublittoral zone. Here we present the first wide-scale application of CARLIT in the Adriatic Sea. The reference values calculated specifically for the Croatian coast (Eastern Adriatic Sea) ensure accurate calculation of the ecological status. The measured ecological quality ratio values (EQR) show a good linear relation with the Land Uses Simplified Index (LUSI) and appropriately reflect an increase in nutrient concentrations. The results suggest that this method can be used as a reliable biomonitoring tool in the Eastern Adriatic Sea. This study highlighted that Cystoseira forests thrive in 39% of the surveyed coastline and 23% of the coastline seems to be subjected to overgrazing by sea urchins. Our results provide a spatially accurate information on the abundance of different upper-sublittoral communities and the associated ecological status, which can be used in future management plans for improving water quality.  相似文献   

4.
In accordance with the Water Framework Directive guidelines (WFD, 2000, European Communities Official Journal L327 2000/60/EC), classification schemes and ecological evaluation tools (based on benthic invertebrate fauna data sets from 1990 to 2002) were applied in the lower Mondego estuary. Two distinct scenarios could be tested due to the implementation of mitigation practices in 1999, following a long eutrophication process, which started by the early 1980s. Some discrepancies in the results were found by the application of the different indices. The AMBI index (accounting for taxonomic composition) and the ABC method (accounting for abundance and biomass k-dominance patterns) classifications often disagreed with those based on species diversity (Margalef and Shannon-Wiener). The ambiguous results made the classification a complex task to achieve, contrary to the Directive’s objective of maintaining it simple and clear. Our results suggest the necessity of adjusting some of the indices and their ranges to estuarine characteristics, namely to account the typical dominance and abundance of some particular species. These aspects are not taken into consideration by some of the indices proposed, which are more adapted to typical marine conditions. Based on our results, these widely applied indices might still improve their efficiency in estuarine systems allowing their use in the resembling types already established within the new Directive agenda.  相似文献   

5.
藻类对水体环境变化敏感,其种类和数量与环境因素有密切联系并因环境的变化而发生变化,因此藻类常作为河流健康评价的指示生物。水体中的藻类根据生活习性不同分为着生藻类和浮游藻类,在河流健康评价中,以往的工作中有的采用浮游藻类用于河流健康评价,有的采用着生藻类用于评价,但浮游藻类和着生藻类究竟何者用于河流健康评价更适宜,抑或是二者在用于评价的适宜性上没有明显差别,迄今为止未开展过深入研究。选择三峡库区内的两条河流嘉陵江和乌江作为研究对象,于2015年9月,在两条河流上共布设11个研究断面,对嘉陵江、乌江的水环境理化因子、着生藻类和浮游藻类群落进行调查研究,应用着生藻类生物完整性指数(Periphytic algal index of biological integrity,Pe-IBI)和浮游藻类生物完整性指数(Phytoplankton index of biological integrity,Ph-IBI),并结合水体综合污染指数(Comprehensive pollution index,CPI),对嘉陵江、乌江的健康状况进行评价。研究结果表明,采用着生藻类生物完整性评价(Pe-IB...  相似文献   

6.
Intertidal seagrass has been selected as a Biological Quality Element for the assessment of ecological status under the Water Framework Directive. In Ireland, two species of seagrass, Zostera marina and Z. noltei occur in intertidal habitats. This study presents the first comprehensive assessment of the distribution and Water Framework Directive status of intertidal seagrass in the Republic of Ireland and Northern Ireland. Most of the areas assessed, using the Water Framework Directive-compliant assessment tool, have a status of HIGH or GOOD. Only two areas were found to have a status less than GOOD and in both, the cause for the decline was smothering by opportunistic foliose green macroalgae. Linear regression showed a relationship between pressure index scores and Ecological Quality Ratio, showing the relevance of the index as a metric of anthropogenic pressure. Trace element concentrations were examined in Z. noltei tissues and Trace Element Pollution Index values were calculated. The relationship between Trace Element contamination and Water Framework Directive status was examined but the results showed little correlation. However, a relationship between the pressure index and trace element contamination was obtained. This assessment provides the most comprehensive overview of intertidal seagrass beds in Ireland and establishes a strong baseline for ongoing monitoring and assessment under the Water Framework Directive. The data provide key information on the pressures affecting these valuable habitats which will assist in the development of measures to improve and protect our transitional and coastal waters.  相似文献   

7.
8.
依据2012年12月对太湖29个样点和同一地理区划4个湖、库的浮游植物和环境变量的监测结果,应用生物完整性理论和方法,构建冬季太湖浮游植物生物完整性指数,评价冬季太湖水生态健康质量。采用干扰程度最小系统法定义筛选确定参照点,对51个候选参数进行分布范围筛选、判别能力分析、参数间相关性分析,获得了太湖枯水期P-IBI指数的6个构成参数:总分类单元数、硅藻门分类单元%、细胞Simpson指数、细胞密度、硅藻门细胞密度%和绿藻门个体密度%。采用比值法统一各参数的量纲,累加后得到枯水期太湖P-IBI分值,并划分健康评价标准。应用P-IBI对冬季太湖水生态进行评价,8个参照点中1个点位评价结果为健康其余7个为亚健康;25个受损点中,2个点位为亚健康,9个点位为一般,12个点位为差,2个点位为极差。太湖总体受到了不同程度的人为干扰,东太湖湖区水生态状况最好,评价结果多为亚健康或一般;竺山湖、贡湖、东部沿岸和西部沿岸次之;南部沿岸和湖心区最差,湖心区有2个点位评价结果为极差。与冬季太湖P-IBI指数显著相关的水化学因子是氨氮和总磷含量。  相似文献   

9.
For the European Parliament and Commission to implement the Water Framework Directive (WFD), the water-quality indices that are currently used in Europe need to be compared and calibrated. This will facilitate the comparative assessment of ecological status throughout the European Union. According to the WFD, biologic indices should respond consistently to human impacts, using multimetric approaches and water-quality classification boundaries adjusted to a common set of normative definitions. The European Commission has started an intercalibration exercise to review biologic indices and harmonize class boundaries. We used data from rivers in Spain to compare the IBMWP (Iberian Biological Monitoring Working Party) index, which is commonly used by water authorities in Spain and by several research centers, with the Intercalibration Common Multimetric Index (ICM-Star), which was used as a standard in the intercalibration exercise. We also used data from Spanish rivers to compare the multimetric indices ICM-7 (based on quantitative data) and ICM-9 (based on qualitative data) with the IBMWP. ICM-7 and ICM-9 were proposed by the Mediterranean Geographical Intercalibration Group (Med-GIG). Additionally, we evaluated two new multimetric indices, developed specifically for macroinvertebrate communities inhabiting Mediterranean river systems. One of these is based on quantitative data (ICM-10), while the other is based on qualitative data (ICM-11a). The results show that the IBMWP index responds well to the stressor gradient present in our data, and correlates well with ICM-Star. Moreover, the IBMWP quality class boundaries were consistent with the intercalibration requirements of the WFD. However, multimetric indices showed a more linear relation with the stressor gradient in our data, and less variation in reference values. In addition, they may provide more statistical power for detecting potential environmental impacts. Multimetric indices produced similar results for quantitative and qualitative data. Thus, ICM-10 (also named IMMi-T) and ICM-11a (also named IMMi-L) indices could be used to meet European Commission requirements for assessing the water quality in Spanish Mediterranean rivers. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Handling editor: Joel Trexler  相似文献   

10.
The use of borrowed indices to assess stream health has limitations and research suggests a need to develop more reliable regionally based indices that are sensitive to the relationship between taxa and environmental conditions. Implementing this is challenging in the Southern Hemisphere given the scarcity of diatom indices, specifically in sub-tropical areas. The purpose of this study was to develop a regionally based diatom index to assess freshwater lotic systems in sub-tropical eastern Australia and compare the results with borrowed indices to derive meaningful inferences on river health. A total of 119 epilithic diatom and water samples were collected during 2014–2015 from the Richmond River Catchment in Northern NSW Australia. Statistical analysis indicated that total phosphorus (TP) and total nitrogen (TN) were strong variables influencing the data set and subsequently TP was chosen as a nutrient proxy for the index. Analysis of diatoms resulted in TP sensitivity values (1–5) being assigned to 105 species with relative abundance of >1% in the data set. These species were used to calculate the Richmond River Diatom Index (RRDI) for 45 sites within the Catchment. The index effectively scored sites along the environmental gradient with sites in the upper catchment generally scoring lower (healthier) than the mid and lower catchment sites. The index compared positively with both the Diatom Species Index for Australian Rivers (DSIAR) (r = 0.76) and the Trophic Diatom Index (TDI) (r = 0.65). Further research is suggested to test the RRDI on independent sites in neighbouring catchments and develop class boundaries from the RRDI so that the index can be readily used by water managers to assess and monitor freshwater systems in sub-tropical Australia.  相似文献   

11.
土地利用空间格局是影响区域生态系统健康状态的重要因素。构建适用于舟山岛生态系统健康诊断的"活力-组织结构-恢复力-生态系统服务功能"评价指标体系,其活力以植被相对密度指数表征、组织结构以蔓延度等4个景观格局指数表征。选择镇、乡或街道等行政区作为评价单元,以遥感数据和土地利用调查数据为基础,采用G IS和RS技术,提取舟山岛17个乡镇1970-2005年间5个时期的土地利用空间格局和指标信息,采用综合参数评价模型对研究区生态系统健康进行时空动态评价。研究结果表明:(1)35 a来舟山岛生态系统健康整体状况呈下降趋势,相对较好的区域面积下降了18%,相对一般的下降了8%,而相对较差的上升了26%;(2)城市化、滩涂围垦与沿海工业的发展是舟山岛生态系统健康状态下降的主要原因。  相似文献   

12.
多尺度生态系统健康综合评价——以宁波市为例   总被引:5,自引:0,他引:5  
以宁波市为例,从市域、所辖县(市/区)、生态系统3个尺度,划分出城市、森林、河流、农田、湖库及海岸带六类生态系统,选定56个指标因子建立了宁波市生态系统健康评价体系,并采用生态系统健康指数法进行了多尺度综合评价。结果显示:(1)宁波市生态系统处于亚健康状态,(2)县(市/区)生态系统中慈溪、象山和镇海为亚健康偏向预警水平,主城区(海曙区、江东区和江北区)、北仑、余姚、鄞州、奉化和宁海为一般健康水平;(3)对宁波市生态系统健康影响的生态系统类型主要是海岸带、河流和农田,县(市/区)主要是慈溪、镇海和象山,影响因子主要是海岸带初级生产力、海水综合污染指数、河流水环境质量和农田系统生产力。根据评价结果,提出重点在农田、河流和海岸带相关方面制定管理措施和开发政策。同时本研究表明,多尺度综合评价方法有助于生态环境管理部门全面直观认识不同尺度上生态系统健康状态,并具体分析主要的影响因子,进行区域生态环境管理的科学决策。  相似文献   

13.
Growing evidence indicates that systemic inflammation response and malnutrition status are correlated with survival in certain types of solid tumors. The aim of this study is to evaluate the association between the systemic immune-inflammation index (SII) and prognostic nutritional index (PNI) and overall survival (OS) in patients with esophageal squamous cell carcinoma (ESCC) after esophagectomy. A consecutive series of 655 patients with resected ESCC who underwent esophagectomy were enrolled in the retrospective study. The preoperative SII was defined as platelet × neutrophil/lymphocyte counts. The PNI was calculated as albumin concentration (g/L) + 5 × total lymphocyte count (109/L). The optimal cut-off values of SII, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and PNI were determined by receiver operating characteristic analysis. Survival analysis was performed using the Kaplan–Meier method with a log-rank test, followed by a multivariate Cox proportional hazards model. A high SII was significantly related to tumor size, histological type, invasion depth, and TNM stage (p < 0.05). A low PNI was significantly associated with age, tumor size, invasion depth, lymph node metastasis, and TNM stage (p < 0.05). Univariate analysis revealed that age, smoking history, tumor size, invasion depth, lymph node metastasis, SII, NLR, PLR, and PNI were predictors of OS (p < 0.05). Multivariate analysis identified age (p = 0.041), tumor size (p = 0.016), invasion depth (p < 0.001), lymph node metastasis (p < 0.001), SII (p = 0.033), and PNI (p = 0.022) as independent prognostic factors correlated with OS. There was a significant inverse relationship between the SII and PNI (r = 0.309; p < 0.001). The predictive value increased when the SII and PNI were considered in combination. Our results demonstrate that the preoperative high SII and low PNI are powerful indicators of aggressive biology and poor prognosis for patients with ESCC. The combination of SII and PNI can enhance the accuracy of prognosis.  相似文献   

14.
The tolerance of microbenthic algal communities to two model toxicants,atrazine and copper, was studied in the Ter river during spring and summer.Artificial substrata were colonised at 9 sites and used to perform short-term(1–4 h) toxicity tests in the laboratory and to obtain photon yield as theecotoxicological endpoint. The tolerance was lower in spring than insummer for both toxic substances and varied according to the site studied.Copper toxicity was associated with physico-chemical conditions (totalsuspended solids and water pH) and, especially, with severalbiomass-related parameters, whereas atrazine toxicity was related to algalabundance and species composition. Temporal and spatial changes innutrient concentration may alter the biomass and species composition ofthe communities and thus affect their tolerance to toxic substances. It hasto be therefore considered that the environmental characteristics of theriver system may determine relevant direct and indirect effects on the algalcommunities, then affecting their specific ecotoxicological responses. Oncethis is assumed, the empirical expressions obtained on calculatingEC50 and EC10 can be used to predict the community-leveltransient effects of toxic exposures.  相似文献   

15.
《水生昆虫》2012,34(2):11-22
A five-year macroinvertebrate study was conducted on a 55 km river (le Rupt-de-Mad, Lorraine region, north-eastern France), a standard for the region. A list of 300 species was drawn up, and remarkable species were listed for some better known orders: Ephemeroptera, Plecoptera, Trichoptera and Odonata. Some faunistic results are emphasised: about 42% of the identified species were more or less ubiquitous, 26% were meso- to polysaprobic species of potamon, present only in the main course of the river, while 31% were rather stenoecious species restricted to certain tributaries. Fifty-one remarkable species were listed, taking into account their regional status, according to IUCN categories: more than three quarters were hosted in the small tributaries, and 55% found exclusively in these latter (versus 23.5% only present in the main course of the river). Calcareous lotic tributaries were hosting particularly original communities with many remarkable species. Ephemeroptera, Plecoptera and Trichoptera were pertinent groups to assess the global faunistic interest of lotic habitats, but lentic habitats are probably better evaluated using other groups, e.g. Odonata and Coleoptera; the latter unfortunately poorly known from an ecological point of view.  相似文献   

16.
唐得昊  邹欣庆  刘兴健 《生态学报》2013,33(4):1240-1250
生态系统健康评价是生态系统保护和监测研究的重要内容,该过程迫切需要综合性强、准确性高的指标,能质和生物多样性指标都是生态系统健康评估中的有效指标.以江苏省海岸带游泳和底栖生物群落为对象,沿海岸线从海州湾到长江入海口北岸选取15个站点,调查研究江苏省海岸带生态系统能质和生物多样性及其空间分布格局.结果表明:江苏海岸带除了中部地区能质和结构能质值较一致(都偏小)外,南北差异明显,生物多样性指数空间分布情况为南部Margalef指数略大于北部,中部较小,Shannon Wiener和Simpson指数空间分布都为南部>中部>北部;能质与生物多样性指标在高级生态系统中反映的生态系统健康状态一致,在中低级生态系统中差异明显;能质与生物多样性指标关联程度低,前者的测算侧重于生态系统中物种的等级,后者的测算侧重于物种的数量;总结能质和生物多样性指标在理论支撑、建立理论视角、与生态系统健康对应关系、应用模型以及局限性等方面的差异,研究结果在一定程度上可以丰富和完善生态系统健康评价研究理论与方法体系.  相似文献   

17.
区县生态系统健康评价方法——以东莞市各镇区为例   总被引:1,自引:0,他引:1  
现有城市生态系统健康研究多集中在城市及城市群层面,未能深入探究城市内部特征。鉴于此,聚焦区县生态系统健康状况,进一步探究城市内部的健康分布特征;提出了"发展水平-服务功能-抵御干扰-自我维育"四维区县生态系统健康评价框架,并建立了相应的多层级指标体系,构建了区县生态系统健康评价模型;在分析区县生态系统健康变化过程及空间分异特征的基础上,识别区县生态系统健康的主要贡献因子。针对东莞各镇区的研究结果表明:1995-2015年间,各镇区生态系统健康状态总体趋于恶化,其中西南地区生态系统的退化比东南地区更为明显。自我维育对各镇区生态系统健康变化具有重要影响,主要瓶颈在于快速发展过程中土地资源的稀缺及较低的利用效率。对区县生态系统健康的研究可以帮助决策者了解城市生态系统复杂的内部特征,在此基础上更好地平衡区域发展、维护城市生态系统健康。  相似文献   

18.
[Purpose]This study aimed to analyze the prevalence of hypertension according to the body mass index (BMI) and relative handgrip strength (RHGS) among elderly individuals in Korea. [Methods]We analyzed the data of 44,183 Korean elderly individuals over 65 years old (men: n = 15,798, age = 73.31 ± 5.04 years, women: n = 28,385, age = 72.14 ± 5.04 years) obtained from the Korean National Fitness Assessment in 2019. All the participants were categorized into three groups according to the BMI and RHGS; additionally, one-way ANOVA and logistic regression analysis were performed. [Results]Overweight (men: 1.16 odds ratio [OR] 1.06–1.26, 95% confidence interval [CI]; women: 1.15 OR, 1.07–1.23 95% CI) and obese (men: 1.54 OR, 1.42–1.66 95% CI; women: 1.44 OR, 1.36–1.53 95% CI) elderly individuals showed a higher prevalence of hypertension than elderly individuals with normal weight, after controlling for age. In men, a lower RHGS was associated with a higher prevalence of hypertension after controlling for age (weak RHGS: 1.09 OR, 1.00–1.17 95% CI; middle RHGS: 1.21 OR, 1.12–1.31 95% CI vs. strong RHGS). [Conclusion]A higher BMI was associated with the prevalence of hypertension in the elderly Korean population. In addition, a lower RHGS was associated with the prevalence of hypertension in elderly Korean men.  相似文献   

19.
明晰平原河网水系结构和功能的影响机制对区域生态可持续发展具有重要意义。以昆山市南部防洪分区为例,选取水系指标分析圩区单元尺度下的水系网络结构与调蓄功能,并构建贝叶斯网络模型,综合考虑用地、自然、工程与政策管理等因子及其相互作用,定量探究水系结构与功能的影响机制。结果表明:(1)水系网络结构具有显著空间异质性,且水系调蓄功能与结构特征密切相关,较复杂的水系形态结构往往表现出较强的调蓄功能;(2)政策、工程、用地和自然条件等因子对水系调蓄功能的影响强度依次减弱;(3)识别水系功能优化目标下的关键变量与关键状态子集,可从社会-生态协同视角指导圩区单元的水系治理与优化。研究结果可为平原圩区水系网络健康与可持续发展提供理论参考和决策依据。  相似文献   

20.
The present work focuses on impact assessment of noise disturbance in the framework of LCA studies. A number of difficulties arose in the course of the study, namely expressing noise measurements in an easy-to-handle unit, imputing disturbance engendered by several simultaneous sources to every single source, handling additive quantities non-linearly, taking into account the space and time dependence of potential impacts associated with noise, It is shown how all these issues were tackled in a I.CA study that assessed different modes of transportation. The methodology developed takes into account the disturbance to noise level exceeding a set threshold and no other kinds of noise effects. It is obvious that disturbance due to noise emissions depends on people density in the neighborhood of the emission source. In this context, a “site-dependent approach” was taken, meaning that we did include local factors into the valuation. The methodology developed in this article may be extended to other types of emissions when it is necessary to integrate local factors in the assessment phase of LCA. This document is the property of Ecobilan and can not be reproduced without its prior authorization  相似文献   

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