共查询到20条相似文献,搜索用时 31 毫秒
1.
Under the Water Framework Directive (WFD) benthic Ecological Quality Ratios (EQRs) are important tools for assessing Ecological Status (ES) of coastal and transitional waters. Calculation of the Multivariate-AZTI Marine Biotic Index (M-AMBI) EQR is based on the proportions of sensitive and stress tolerant benthic invertebrate species, number of species and Shannon–Wiener diversity. The sensitivity of many tropical/sub-tropical taxa has not yet been determined, presenting a barrier to the direct transfer of WFD EQRs, and the ideas underpinning them, to the management of coastal waters beyond Europe. To overcome this we examine using higher taxonomic level data with M-AMBI.Before applying such approaches to assessing ES in new geographical regions it is essential to determine the effects of using higher taxonomic level data on M-AMBI in areas where the tool was developed. To this end, we use macrofaunal data from three well studied sites in north-western Europe to examine the effects of using taxonomic level data higher than species on M-AMBI. Using the European datasets M-AMBI ES classification was shown to be robust to changes in taxonomic level data. We test the suitability of family-level M-AMBI for assessing ES in subtropical Hong Kong waters. Family level M-AMBI was useful in detecting stress in Hong Kong, where it successfully detected temporal and spatial shifts in ES in response to seasonal hypoxia and salinity variability, and anthropogenic organic enrichment. 相似文献
2.
Ricardo Bermejo Luisa Mangialajo Juan J. Vergara Ignacio Hernández 《Journal of applied phycology》2014,26(4):1899-1909
Several indices based on the composition and abundance of aquatic flora have been developed to assess the ecological status of coastal waters along the European coasts in the context of the Water Framework Directive. This directive pointed out the intercalibration of indices based on the same biological element within an eco-region to ensure the consistency and comparability among them. For a better management of coastal areas in the transition zone between two eco-regions, the comparison of indices developed for each eco-region may also be necessary. The aim of this work was to compare two indices based on macrophytes that have been proposed for two different and adjoining eco-regions: the RSL (Reduced Species List) in the Atlantic eco-region and the CARLIT (Cartography of littoral and upper sublittoral communities) in the Mediterranean. These indices were applied in 14 sites in the transition between the Atlantic Ocean and the Mediterranean Sea, where a wide range of anthropogenic pressures can be found, from high (Algeciras Bay) to almost negligible ("El Estrecho" Natural Park). Overall, both indices were sensitive to anthropogenic pressures and suitable to assess the ecological status. The comparison between indices suggested a bias in the assessment of the ecological status between good and high classes due to a different definition of high ecological status class between RSL and CARLIT. In addition, the most important disagreements between indices were found in the most degraded localities. The results showed, however, a high comparability between RSL and CARLIT despite their marked conceptual and methodological differences. 相似文献
3.
A rapid visual assessment (RVA) approach for the characterization and assessment of the integrity of coralligenous reefs was applied in 21 stations subjected to different levels of anthropogenic pressure, along the French Mediterranean coasts. The reefs were characterized from both the geomorphologic and bionomic (biotic cover, conspicuous species richness, canopy-forming species, etc.) points of view, and their health status was estimated through the COARSE (COralligenous Assessment by ReefScape Estimate) index. The sensitivity of the COARSE index and the robustness of the RVA approach to observer biases were analyzed. Results showed that most coralligenous reefs were characterized by (sub) vertical cliffs or platforms with variable slope, usually dominated by biotic facies with Paramuricea clavata and/or Eunicella cavolini in healthy stations, or by algal associations or facies of impoverishment in the most impacted situations. The overall quality scores of the COARSE index generally reflected the putative level of stress of the sampling stations; differences due to observer biases resulted negligible. Coupling the RVA approach with the COARSE index proved an effective protocol for both the characterization and the evaluation of coralligenous reefs: the former is achieved by the analysis of the whole complexity of this habitat, the latter provides for the first time an indication of sea-floor integrity, differently from previous indices that aim at estimating water quality. 相似文献
4.
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
5.
The Finnish fish-based lake assessment system EQR4 was updated using more extensive lake data with tighter reference criteria. The updated EQR4 (EQR4new) had significant and tighter pressure (eutrophication) relationship compared to the previous version (EQR4old). The EQR4new separated impacted and reference lakes with lower misclassification risk compared to the EQR4old. All the variables within the multi-metric index EQR4new (total biomass, total number of individuals, cyprinid biomass %, and indicator species) were found to be relevant. The classification output in relation to eutrophication was higher in the northern part of the country compared to the southern lakes which was probably due to the climate-dependent reduction in productivity. Despite the clear pressure response and the ability to separate reference and impacted lakes, the accuracy of the EQR4new values is relatively modest. Including regional patterns in the composition and variability of lake fish communities in Finland would increase the accuracy of the assessment method and, moreover, contribute to the excellence of fish community ecology of boreal lakes. 相似文献
6.
7.
Cecilia Lopez y Royo Cecilia Silvestri Maylis Salivas-Decaux Gerard Pergent Gianna Casazza 《Hydrobiologia》2009,633(1):169-179
The Biotic Index based on Posidonia oceanica (BiPo) is a classification system for evaluation of the ecological status in Mediterranean coastal waters, developed in accordance with the EU Water Framework requirements. The aim of this study is to verify the applicability and reliability of the BiPo index to different geographical areas of the north-western Mediterranean (France, Spain and Italy), to understand whether such a classification system may be applied more extensively, as so far it has only been applied to coastal waters in Corsica. The ecological status determined for sites is verified against pressures revealed from satellite imagery and from trace metal contamination of plants, to identify the sources of pressure that may be responsible for a low ecological status. The results of this study indicate that: (i) the BiPo index responds reliably to pressures, in different areas of the Mediterranean; (ii) sites with an ecological quality ratio (EQR) close to the good/moderate boundary require particular attention to identify and reduce causes of deterioration; (iii) the support of chemical indicators, in this case metal contamination, is relevant to identify potential sources of pressure. 相似文献
8.
A fish – based index for the assessment of the ecological quality of natural temperate lakes was developed, in accordance to the requirements of the Water Framework Directive (WFD) 2000/60/EC. As a case study, 11 natural lakes located at northern and western Greece were selected. Fish surveys were conducted during mid summer to mid autumn in 2010, 2011 and 2012 using Nordic gillnets and electrofishing. Environmental parameters and anthropogenic pressures were assessed for each lake. Fish species richness, abundance, trophic, reproductive and habitat functional guilds were used for extracting a set of 107 metrics, meeting the requirements of the WFD. All metrics were initially tested as candidates for the index development. A stepwise linear regression of each metric against environmental parameters (lake area, altitude, maximum depth, alkalinity) and anthropogenic pressures (drainage area covered by non-natural land uses – NNLC, water total phosphorus concentrations – TP, Lake Habitat Modification Score – LHMS) was initially conducted for ensuring pressure-response relationships. Reference conditions for each lake were estimated by the hindcasting procedure and the ecological quality for each lake was expressed as the ecological quality ratio (EQR) by a value ranging from 0 (poor quality) to 1 (excellent quality). Two fish fauna metrics, the relative numerical abundance of introduced species (Introduceda) and the relative biomass of omnivorous species (OMNIb) were finally extracted as the most significant, responding to LHMS and TP, respectively. The final index was expressed as the mean values of the EQRs of these two metrics. The multimetric fish index presented herein could serve as a tool for assessing the ecological quality of natural lakes at broad geographical scale and generally, in the Mediterranean temperate lakes with similar hydromorphological characteristics. 相似文献
9.
J. M. HUGHES A. M. BAKER G. DE ZYLVA P. B. MATHER 《Biological journal of the Linnean Society. Linnean Society of London》2001,74(1):25-34
The Australian magpie ( Gymnorhina tibicen ) is polymorphic for back colour with three distinct morphs recognized: the black-backed form (BB) which occurs in northern and north-eastern Australia; the white-backed form (WB) which occurs in south-eastern Australia and Tasmania and the Western form which occurs in the far south-west corner of the continent. Male and female WBs and BBs are both monomorphic for back colour while Westerns are sexually dimorphic, with males white-backed and females black-backed. In the south-east the WB and BB distributions overlap with individuals of intermediate phenotype interspersed with pure WB and BB phenotypes. This study used mtDNA control-region sequences to test the predictions of two alternative hypotheses to explain the distribution of WB and BB populations in eastern Australia and Tasmania. Our data support the hypothesis that the variation has evolved in situ, as no population genetic structuring was evident in eastern Australia related to back colour and Tasmanian WBs were no more closely related to mainland WBs than to mainland BBs (primary contact hypothesis). Back colour patterns may be maintained by different forms of natural selection favouring BB genes in the north-east and WB genes in the south-east. 相似文献
10.
广东省生态安全状态及趋势定量评价 总被引:27,自引:3,他引:27
为研究区域生态安全在不同时期的动态变化及发展趋势,在国内外已有的研究基础上,根据压力-状态-响应模型框架,提出了一套完整的区域生态安全水平度量的指标体系和基于熵权法赋权的综合指数评价方法,从时间尺度上(1990~2004年)对广东省生态安全进行定量评估和动态趋势分析.结果表明,广东省生态安全综合指数从1990年的0.125增加至2004年的0.402,生态安全整体水平呈逐年上升趋势,但发展过程中存在的问题是区域生态压力在不断加大及生态安全现状水平仍处于“较不安全”状态.对广东省环境规划的实施效果进行预测评估,得出在实现环境目标的情景下,2010规划年和2020规划年的生态安全综合指数将分别达到0.533(临界安全)和0.691(较安全).评价方法简单直观,评价结果客观合理. 相似文献
11.
S. Orfanidis K. Dencheva K. Nakou S. Tsioli V. Papathanasiou I. Rosati 《Hydrobiologia》2014,740(1):61-78
Benthic macrophyte communities of different substratum types (soft, hard) were studied in eleven differently impacted sites belonging in two different water typologies (transitional waters: Lesina Lagoon, Varna Lake; coastal waters: Varna Bay) and two ecoregions (Mediterranean Sea, Black Sea). Species lists were compiled for each study site, 20 taxa were found at Lesina and Varna Lake and Bay, and the abundance of each taxon was determined at each site. The relationship between nine metrics related to community structure [species richness, % of total coverage, dry biomass (g/m?2), and cluster and multi-dimensional scaling plot of Bray–Curtis similarity] and function [Ecological Status Group I % coverage, ESG II % coverage, Ecological Evaluation Index (EEI-c) and Ecological Index (EIEEI)] and key abiotic factors and an anthropogenic stress index (EnII) were studied. A strong relationship (Spearman rank correlation coefficient ρ ≤ ?0.89; R 2 ≥ 0.89) between anthropogenic stress and functional indices, EEI-c and EIEEI, was found. The structural index ‘species richness’ correlated negatively with EnII and positively with salinity, demonstrating a freshwater and confinement influence on species diversity. EEI-c and EIEEI indices classified the studied sites and locations in different Ecological Status Classes in accordance with the anthropogenic stress gradient. 相似文献
12.
ATP prevents Woronin bodies from sealing septal pores in unwounded cells of the fungus Zymoseptoria tritici
下载免费PDF全文
![点击此处可从《Cellular microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Gero Steinberg Martin Schuster Christian Hacker Sreedhar Kilaru Ana Correia 《Cellular microbiology》2017,19(11)
Septa of filamentous ascomycetes are perforated by septal pores that allow communication between individual hyphal compartments. Upon injury, septal pores are plugged rapidly by Woronin bodies (WBs), thereby preventing extensive cytoplasmic bleeding. The mechanism by which WBs translocate into the pore is not known, but it has been suggested that wound‐induced cytoplasmic bleeding “flushes” WBs into the septal opening. Alternatively, contraction of septum‐associated tethering proteins may pull WBs into the septal pore. Here, we investigate WB dynamics in the wheat pathogen Zymoseptoria tritici. Ultrastructural studies showed that 3.4 ± 0.2 WBs reside on each side of a septum and that single WBs of 128.5 ± 3.6 nm in diameter seal the septal pore (41 ± 1.5 nm). Live cell imaging of green fluorescent ZtHex1, a major protein in WBs, and the integral plasma membrane protein ZtSso1 confirms WB translocation into the septal pore. This was associated with the occasional formation of a plasma membrane “balloon,” extruding into the dead cell, suggesting that the plasma membrane rapidly seals the wounded septal pore wound. Minor amounts of fluorescent ZtHex1‐enhanced green fluorescent protein (eGFP) appeared associated with the “ballooning” plasma membrane, indicating that cytoplasmic ZtHex1‐eGFP is recruited to the extending plasma membrane. Surprisingly, in ~15% of all cases, WBs moved from the ruptured cell into the septal pore. This translocation against the cytoplasmic flow suggests that an active mechanism drives WB plugging. Indeed, treatment of unwounded and intact cells with the respiration inhibitor carbonyl cyanide m‐chlorophenyl hydrazone induced WB translocation into the pores. Moreover, carbonyl cyanide m‐chlorophenyl hydrazone treatment recruited cytoplasmic ZtHex1‐eGFP to the lateral plasma membrane of the cells. Thus, keeping the WBs out of the septal pores, in Z. tritici, is an ATP‐dependent process. 相似文献
13.
The SeaGen tidal energy turbine is located in the Strangford Narrows, Northern Ireland. The Narrows are designated as a Natura 2000 site, host unique biological assemblages and exhibit very high tidal velocities.This study describes an asymmetrical BACI design monitoring program that was aimed at assessing the potential impact the SeaGen may have on epifaunal boulder reef communities. This study presents a novel methodology for monitoring epifaunal communities within highly variable and poorly understood tidal rapid environments.We identify bare rock as a key measure of disturbance within tidal energy extraction sites and propose a new successional model for epifaunal reef communities on subtidal stable substrates. We also present an Ecological Quality Ratio (EQR); the High Energy Hard Substrate (HEHS) index for use in monitoring programs within tidal energy extraction sites.Seasonality significantly affected epifaunal community structure, bare rock distributions and EQR values at all stations equally over time. SeaGen is not significantly affecting epifaunal community structure, bare rock distributions or EQR values at the impact site. The HEHS index has the potential to standardise benthic monitoring in tidal energy extraction sites. 相似文献
14.
S. Prato J.G. Morgana P. La Valle M.G. Finoia L. Lattanzi L. Nicoletti G.D. Ardizzone G. Izzo 《Ecological Indicators》2009,9(3):568-583
Marine biotic indices (AMBI, BENTIX) and the statistical tool M-AMBI (Multivariate AMBI) were applied as a comparative approach in assessing the Ecological Quality Status (EcoQS) of two Mediterranean coastal lakes (Caprolace and Fogliano lakes) situated in the Circeo National Park (Central Italy). The macrobenthic community was analysed using univariate indices (community structure), correspondence analysis (CA) and taxonomic distinctness indices (Δ+ and Λ+). The community composition showed a dominance of lagoonal species in both coastal lakes, while in Caprolace lake marine taxa were also found. Diversity index (H′) complies to ranges found in Mediterranean lagoons and taxonomic distinctness indices demonstrated that taxonomy structure is in accordance with natural variability ranges. Principal component analysis (PCA) on chemical parameters of water and sediment showed that both coastal lakes differ mainly in their organic matter composition. In fact, the protein fraction of bio-polymeric carbon prevails in Fogliano lake, while the ‘refractory’ component represented by carbohydrate fraction is predominant in Caprolace lake. The difference between the two coastal lakes was also demonstrated by co-inertia analysis (COIA) performed using abundance of species and concentrations of chemical parameters. The results from the application of the three biotic indices do not highlight a clear distinction between the two lagoons. However, the AMBI index provided a more suitable evaluation of EcoQS corresponding to ‘slightly polluted’ lagoons while M-AMBI and moreover BENTIX indices indicated a worsening situation. The biotic indices are widely used in assessing the EcoQS in marine environments, but their proper application in transitional waters would depend on a resettlement; thresholds established in the biotic index scale values need to be modified according to natural variability of transitional waters referring to abiotic conditions and abundance of tolerant species. 相似文献
15.
A simple procedure to harmonise and intercalibrate eight national methods classifying the ecological status using fish in transitional waters of the North East Atlantic is described. These methods were initially intercalibrated and a new method recently developed was added to this exercise. A common human pressure index pre-classified the status of each water body in an independent way. Ecological class boundaries values were established according to the level of anthropogenic pressure using regression analyses. A simulated dataset was used to assess the level of agreement between the fish classification methods. Fleiss’ multi-rater kappa analysis indicated that boundary harmonisation was achieved; all classifications fell within one class of each other and class agreement between methods exceeded 70%. The use of a pressure index to establish boundary thresholds provides a practical method of defining and harmonizing the quality classes associated with human pressures, as required by the European Water Framework Directive. 相似文献
16.
17.
Due to the intensive mixing polymictic lakes should be homogenous. However, morphometric diversity and high water dynamics contribute to the differentiation of many parameters in various areas of the lakes. This study analyzes both phytoplankton and zooplankton to assess differences in water quality along the north–south axis of the longest lake in Poland. New phytoplankton indicators were applied for determining the lake's ecological status: the Q index based on functional groups and the PMPL (Phytoplankton Metric for Polish Lakes) index based on phytoplankton biomass. TSIROT index (Rotifer Trophic State Index), which comprises the percentage of species indicating a high trophic state in the indicatory group and the percentage of bacteriovorus in the Rotifera population, was used for zooplankton analysis.TP content was different at different sites – we observed its gradual increase from the south to the north. Spatial variation of phosphorus did not considerably affect plankton diversity. The phytoplankton was dominated by Oscillatoriales, typical of shallow, well-mixed eutrophic lakes. The ecological status of the lake based on the EQR (Ecological Quality Ratio) was poor or moderate. The zooplankton was dominated by rotifers (at almost all sites), which indicates a eutrophic state of the lake. The values of phytoplankton indices at the studied sites did not differ considerably; the differences resulted more from local conditions such as the contaminant inflow and the macrophyte development than water dynamics.We have demonstrated that in the lake dominated by filamentous Cyanobacteria the ecological status should be determined according to the PMPL index or other indices dependent on the dominant Cyanobacteria species. Since the Q index does not include the functional group S1, the results can lead to the false conclusion that water quality improves with an increased amount of phytoplankton. The high abundance of Cyanobacteria in the lake may have contributed to the poor growth of rotifers. 相似文献
18.
Eukaryotic organelles evolve to support the lifestyle of evolutionarily related organisms. In the fungi, filamentous Ascomycetes possess dense-core organelles called Woronin bodies (WBs). These organelles originate from peroxisomes and perform an adaptive function to seal septal pores in response to cellular wounding. Here, we identify Leashin, an organellar tether required for WB inheritance, and associate it with evolutionary variation in the subcellular pattern of WB distribution. In Neurospora, the leashin (lah) locus encodes two related adjacent genes. N-terminal sequences of LAH-1 bind WBs via the WB–specific membrane protein WSC, and C-terminal sequences are required for WB inheritance by cell cortex association. LAH-2 is localized to the hyphal apex and septal pore rim and plays a role in colonial growth. In most species, WBs are tethered directly to the pore rim, however, Neurospora and relatives have evolved a delocalized pattern of cortex association. Using a new method for the construction of chromosomally encoded fusion proteins, marker fusion tagging (MFT), we show that a LAH-1/LAH-2 fusion can reproduce the ancestral pattern in Neurospora. Our results identify the link between the WB and cell cortex and suggest that splitting of leashin played a key role in the adaptive evolution of organelle localization. 相似文献
19.
The Water Framework Directive (WFD) is a key legislative action developed by the European Union in order to protect aquatic ecosystems. One of the concerning pollutants, listed in this directive as a priority hazardous substance, is tributyltin (TBT), a biocide largely used in antifouling paints and identified as a causative agent of imposex/intersex in gastropods. In order to integrate TBT pollution monitoring within this legislative framework, a practical exercise is here proposed to assess the evolution of surface water ecological status in Ria de Aveiro (NW Portugal). Three bioindicators – the caenogastropods Nucella lapillus, Nassarius reticulatus and Littorina littorea – were used under the general WFD benthic invertebrate quality element, and the vas deferens sequence index (VDSI) and the intersex index (ISI) were selected as biomarkers for the purpose of assessing the condition of this quality element regarding the impact of TBT pollution. Levels of VDSI in N. lapillus and N. reticulatus, and ISI in L. littorea, were surveyed in 2013 and compared with previous data available for the same species and study area in 1998 and 2005, providing a time lapse for a period of 15 years. VDSI and ISI values were converted into Ecological Quality Ratios (EQR) and EQR boundaries were set for each species in order to define the five ecological status classes (High, Good, Moderate, Poor and Bad). We propose N. lapillus as key bioindicator, however the combined use of further species is very useful to cover a wider study area. Based on the proposed method, it is concluded that the ecological status of the surface waters surveyed in Ria de Aveiro, concerning the impact of TBT pollution on the above benthic invertebrate taxa, improved considerably since 1998 and achieved a Good Ecological Status in 2013, thus meeting the WFD environmental objectives for this priority hazardous substance even before 2015. 相似文献
20.
《Ecological Indicators》2005,5(1):19-31
In recent years, several benthic biotic indices have been proposed to be used as ecological indicators in estuarine and coastal waters. One such indicator, the AZTI Marine Biotic Index (AMBI), was designed to establish the ecological quality of European coasts. The index examined the response of soft-bottom benthic communities to natural and man-induced disturbances in coastal and estuarine environments. It has been successfully applied to different geographical areas and under different impact sources, with increasing user numbers in European marine waters (Baltic, North Sea, Atlantic and Mediterranean). The AMBI has been used also for the determination of the ecological quality status (EcoQ) within the context of the European Water Framework Directive (WFD).In this contribution, 38 different applications including six new case studies (hypoxia processes, sand extraction, oil platform impacts, engineering works, dredging and fish aquaculture) are presented. The results show the response of the benthic communities to different disturbance sources in a simple way. Those communities act as ecological indicators of the ‘health’ of the system, indicating clearly the gradient associated with the disturbance. 相似文献