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1.
The relationship between soft-bottom macrobenthic communities and environmental variables in Singaporean waters 总被引：1，自引：0，他引：1
Lu L 《Marine pollution bulletin》2005,51(8-12):1034-1040
Univariate and multivariate methods were used to study soft-bottom macrobenthos collected in December 2002 from the coastal waters of Singapore. The univariate parameters and community structure of benthic communities were related to environmental variables. Three samples were taken with a 0.1 m2 Van Veen grab (33 × 30 × 15 cm) at each station from 12 sampling stations of two different geographical areas. The water depth ranged from 6.5 m to 34.0 m. The mean values of species number, abundance and species diversity (H′) were 24 species/grab, 77 animals/grab and 3.35/grab, respectively. A total of 172 species was recorded. Total petroleum hydrocarbons were strongly negatively related to species number, abundance and species diversity, suggesting that petroleum hydrocarbons have harmful effects on macrobenthic communities. The BIO-ENV analyses for all stations identified median particle size, silt–clay content, salinity and Zn as the major environmental variables influencing the infaunal patterns. However, separate analyses for two areas produced stronger correlations and different best-correlated environmental variable combinations. Total petroleum hydrocarbons were the only common factor in both areas, showing the importance of petroleum contamination in determining the community structure of benthic infauna in Singaporean waters. 相似文献
2.
Sediment particle size analysis (PSA) is routinely used to support benthic macrofaunal community distribution data in habitat mapping and Ecological Status (ES) assessment. No optimal PSA Method to explain variability in multivariate macrofaunal distribution has been identified nor have the effects of changing sampling strategy been examined. Here, we use benthic macrofaunal and PSA grabs from two embayments in the south of Ireland. Four frequently used PSA Methods and two common sampling strategies are applied. A combination of laser particle sizing and wet/dry sieving without peroxide pre-treatment to remove organics was identified as the optimal Method for explaining macrofaunal distributions. ES classifications and EUNIS sediment classification were robust to changes in PSA Method. Fauna and PSA samples returned from the same grab sample significantly decreased macrofaunal variance explained by PSA and caused ES to be classified as lower. Employing the optimal PSA Method and sampling strategy will improve benthic monitoring. 相似文献
3.
Ifigenia Kagalou Georgios Economidis Ioannis Leonardos Constantinos Papaloukas 《Limnologica》2006,36(4):269-278
Macroinvertebrates play a key role in freshwater lentic and lotic ecosystems. The macroinvertebrate benthic community of a shallow Mediterranean lake (Lake Pamvotis, NW Greece) was studied. The benthic assemblage was sampled monthly at five sites during a period of 1 year (Apr. 1998–Mar. 1999). In addition hypolimnetic water quality variables were monitored over the same period at each site.
The aim of the study was (a) to describe the intra-annual and spatial variability in benthic communities, (b) to relate possible community changes to environmental conditions and (c) to evaluate the responses of the lake's ecological status on community indices.
The benthic fauna of Lake Pamvotis was found to be very limited with a total of 10 species belonging to five taxonomic groups. The oligochaete community comprised 80% of the total benthic fauna with Potamothrix bavaricus as a new record for the Lake Pamvotis and Potamothrix hammoniensis, being the dominant benthic species represented more than 61% of the total benthic fauna. Chironomus plumosus was the most abundant chironomid species contributing with about 6% of the total benthic fauna, and Chaoborus flavicans with 19% was the important dipteran. Almost all benthic species showed the same intra-annual seasonal pattern, with peak population densities during spring and early summer except P. hammoniensis which predominated during the whole sampling period. Dissolved oxygen and temperature seemed to be the main environmental factors affecting community indices.
Benthic communities are affected by human disturbances in Lake Pamvotis shifting their composition to more tolerant taxa, reflecting also the eutrophic to hypertophic character of the lake. 相似文献
4.
Fabio Bertasi Francesco Colosio Gianni Gregorio Marco Abbiati Victor Ugo Ceccherelli 《Marine pollution bulletin》2009,58(5):686-694
Sandy shores on the West coast of the North Adriatic Sea are extensively protected by different types of defence structures to prevent coastal erosion. Coastal defence schemes modify the hydrodynamic regime, the sediment structure and composition thus affecting the benthic assemblages. This study examines the effectiveness in detecting changes in soft bottom assemblages caused by coastal defence structures by using different levels of taxonomic resolution, polychaetes and/or bivalves as surrogates and different data transformations. A synoptic analyses of three datasets of subtidal benthic macrofauna used in studies aimed at assessing the impact of breakwaters along the North Adriatic coast has been done. Analyses of similarities and correlations between distance matrices were done using matrices with different levels of taxonomic resolution, and with polychaetes or bivalves data alone. Lentidium mediterraneum was the most abundant species in all datasets. Its abundance was not consistently related to the presence of defence structures. Moreover, distribution patterns of L. mediterraneum were masking the structure of the whole macrofaunal assemblages. Removal of L. mediterraneum from the datasets allowed the detection of changes in benthic assemblages due to coastal defences. Analyses on different levels of taxonomic resolution showed that the level of family maintained sufficient information to detect the impacts of coastal defence structures on benthic assemblages. Moreover, the outcomes depended on the transformation used. Patterns of distribution of bivalves, used as surrogates, showed low correlations with the patterns of the total macrofaunal species assemblages. Patterns of polychaetes, if identified to the species or genus level showed higher correlations with the whole dataset. However, the identification of polychaetes to species and genus level is as costly as the identification of all macrobenthic taxa at family level.This study provided additional evidences that taxonomic sufficiency is a useful tool in environmental monitoring, also in investigations on the impacts of coastal defence structures on subtidal macrofauna. The use of coarser taxonomic level, being time-efficient, would allow improving sampling designs of monitoring programs by increasing replication in space and time and by allowing long term monitoring studies. 相似文献
5.
On data of bottom sampling, carried out by means of grab, trawl and underwater photography in August–September of 1993 in the area of the Pechora Sea, quantitative regularities of macrobenthos distribution are described for the ecological monitoring purposes. Maps of -biodiversity and biomass indices, bottom communities and trophic zones, singled out by dominant method, are presented. Assessment of structure changes of the investigated area bottom communities during the last 60–70 years is fulfilled. It is shown that the described communities on the whole are of natural undisturbed character and that the revealed changes are within the natural fluctuations in the abundance of benthic populations or may be interpreted in terms of methodical differences in the data analysis and generalization by different authors. 相似文献
6.
7.
Zenetos A Hatzianestis J Lantzouni M Simboura M Sklivagou E Arvanitakis G 《Marine pollution bulletin》2004,48(1-2):122-131
The sinking of the tanker Eurobulker in Southern Evoikos gulf (Aegean Sea, Greece) in September 2000 resulted in a spill of 700 tons of crude oil. The environmental impact of the spill was studied by the National Centre for Marine Research. The hydrocarbon concentrations in water, sediment and coastal benthic organisms were measured and the response of the benthic communities to the disturbance caused by the oil spill was studied along the direction to the coast and over three sampling seasons. The most severe and direct effects were evidenced on the muddy benthic communities of the accident site and the stations in the close vicinity sampled shortly after the spill. The effects included reduction of the species richness and community diversity, but the communities reached full recovery 8 months later. The impact of the spill was more indirect and delayed in the coastal stations, where as the hydrocarbon measurements indicated, the pollutants were transported later and induced their effects on the benthic communities 6 months after the accident. 相似文献
8.
A new fish-based multi-metric assessment index for cyprinid streams in the Iranian Caspian Sea Basin
《Limnologica》2015
A major issue for water resource management is the assessment of environmental degradation of lotic ecosystems. The overall aim of this study is to develop a multi-metric fish index for the cyprinid streams of the Caspian Sea Basin (MMICS) in Iran. As species diversity and composition as well as population structure in the studied streams are different to other regions, there is a substantial need to develop a new fish index. We sampled fish and environmental data of 102 sites in medium sized streams. We analysed human pressures at different spatial scales and determined applicable fish metrics showing a response to human pressures. In total, five structural and functional types of metrics (i.e. biodiversity, habitat, reproduction, trophic level and water quality sensitivity) were considered. In addition, we used 29 criteria describing major anthropogenic human pressures at sampling sites and generated a regional pressure index (RPI) that accounted for potential effects of multiple human pressures.For the MMICS development, we first defined reference sites (least disturbed) and secondly quantified differences of fish metrics between reference and impaired sites. We used a Generalised Linear Model (GLM) to describe metric responses to natural environmental differences in least disturbed conditions. By including impaired sites, the residual distributions of these models described the response range of each metric to human pressures, independently of natural environmental influence.Finally, seven fish metrics showed the best ability to discriminate between impaired and reference sites. The multi-metric fish index performed well in discriminating human pressure classes, giving a significant negative linear response to a gradient of the RPI. These methods can be used for further development of a standardised monitoring tool to assess the ecological status and trends in biological condition for streams of the whole country, considering its complex and diverse geology and climate. 相似文献
9.
Little information currently exists on spatial and temporal benthic community variations in tropical coastal lagoons. Here, the benthic community response to habitat variation in the Celestun coastal lagoon, northwest Yucatan peninsula, was seasonally examined during the 1994–1995 climatic cycle into a grid of 12 sampling sites distributed along the salinity gradient of the lagoon. Habitat variation was assessed through physical factors associated both to the water column (e.g. salinity) and the bottom sediment (e.g. sand, silt and clay fractions). The benthic community response was assessed through species diversity measures and abundance. Under the influence of climatic seasonality, variations in habitat conditions followed by changes in the benthic community characteristics were expected. Results from two-way ANOVAs showed that for the period of study, Celestun lagoon was more heterogeneous along the spatial axis of variability than along the temporal one. Multiple regression analysis showed that salinity was spatially the main factor influencing the benthic community characteristics. Temporally, the sediment characteristics were observed to exert significant effects on the species diversity characteristics but not on abundance. Other variables assessed (dissolved oxygen, pH, temperature and water column transparency) exhibited no significant covariance with species diversity and abundance. Since generated from historical data, these results have the potential to be useful as a benchmark to the establishment of monitoring programs in the light of the increasing anthropogenic pressure on the natural resources of the lagoon and surrounding coastal area. 相似文献
10.
A two-year study was conducted in the vicinity of a harbour in sub-tropical Hong Kong, to examine the progress of recovery of macrobenthic community, based on analyses of both life-history traits and trophic guilds of polychaetes, upon cessation of organic pollution caused by sewage discharge. Seventy seven out of 83 species collected were classified under four ecological groups based on the life-history traits and sensitivity to organic gradients. The mean ATZI marine biotic index (AMBI) derived from these ecological groups showed spatial difference among the five sampling locations. In particular, the presence of different percentages of polychaete species from Groups III (unbalanced community) and IV (polluted community) suggested the presence of pollution stress in certain degree at all sampling locations. However, no significant temporal changes were noted over the study period. From all polychaete species identified, they were classified into 13 feeding guilds. The mean diversity of these feeding guilds at most of the sampling locations was significantly higher than that at one of the inside-harbour locations. The composition of feeding guilds was also significantly different spatially. At one of the inside-harbour locations, the dominant feeding guilds were motile/discretely motile surface deposit feeders with tentaculates or unarmed pharynx, and motile omnivores with jawed pharynx in the first year of study, but were replaced by motile, jawed carnivores in the second year of study. The increased proportion of carnivores over the study period can be seen as a sign of recovery in the community structure since abundance of predators is commonly higher in habitats with better environmental quality. The implications of using life-history traits and feeding guild analyses for benthic community are discussed. 相似文献
11.
《Limnologica》2020
Many streams and rivers worldwide are restored with the intention to mitigate degradation caused by human activities, but these rehabilitation projects often involve physical instream work with diggers or other heavy machinery. The short-term effects of such restoration works on stream ecosystems are rarely investigated. The primary aim of our study was to assess the short-term effects of physical instream restoration works (which likely increased instream fine sediment load temporarily) on the benthic macroinvertebrate community in a lowland soft-bottomed stream, and our second aim was to compare the results of semi-quantitative kick-net and quantitative Surber sampling in this assessment. Invertebrates were collected using these two methods from three Control and three Impact sites, before and two days after recontouring the stream banks and installing instream woody cover features. Three of seven macroinvertebrate community-level indexes suggested positive short-term effects of the restoration works, whereas none indicated negative effects. By contrast, seven of the 14 most common taxa were negatively affected by the restoration works, possibly due to increased fine sediment levels reducing habitat quality for these taxa. These differences imply that taxon-specific invertebrate responses may be more suitable for detecting short-term impacts of instream restoration works than community-level metrics. Community indexes and common taxa were also likely affected by a drought in the spring and summer before restoration, which may have obscured some effects of the restoration works. Finally, kick-net and Surber sampling methods yielded similar findings for the community-level metrics but differed more for the common taxa, probably because the two methods sampled different microhabitats within the stream. Consequently, we recommend that for routine monitoring of macroinvertebrate communities in lowland soft-bottomed streams, the semi-quantitative kick-net sampling method should be used. 相似文献
12.
Sustainable impact of mussel farming in the Adriatic Sea (Mediterranean Sea): evidence from biochemical, microbial and meiofaunal indicators 总被引：3，自引：0，他引：3
We have investigated the impact of a large mussel farm on the benthic environment using a battery of benthic indicators of environmental quality (including biochemical, microbial and meiofaunal parameters). These were analysed through a multi-control sampling strategy over one year. The differences across the seasons are typically higher than those between the impacted and the control stations. No effects are seen in terms of the sediment oxygen penetration and the downward fluxes (as the total mass, organic and phytopigment fluxes). The indicators based on the biochemical compositions of the sediment organic matter and the microbial parameters also show no evidence of the eutrophication process, except as a slight increase in the bacterial density in the sediments beneath the long-lines of the farm during the period of highest mussel stocks. Finally, no effects are observed in terms of the benthic faunal indicators, as the meiofaunal abundance, the community structure and the taxa richness are all indistinguishable between the farm sediments and the controls. These results show that mussel farming in the investigated system is eco-sustainable and does not significantly alter the coastal marine ecosystem, both in terms of the functioning and the trophic state. The battery of indicators selected in this study represents a useful tool for the monitoring of the potential ecological impact of mussel farms, towards guaranteeing the sustainable development of aquacultures in shallow coastal environments. 相似文献
13.
《Marine pollution bulletin》2014,78(1-2):130-136
For heavy metals, quality standards indicating good environmental status are designed to evaluate concentrations in the whole fish body, whereas monitoring of metals is often conducted using muscle or liver tissue. As most metals accumulate at different rates in different parts of fish, data should be adjusted to reflect whole fish body concentrations; however, this requires knowledge on distribution of metal concentrations within fish. Here, concentrations of cadmium, mercury, and lead were analyzed in the liver, muscle and whole fish of herring and perch to create conversion factors for transformation of heavy metal concentrations between these tissues. Species-specific accumulation of metals between muscle, liver, and whole fish were observed. Relationships between different tissues were used to recalculate data from monitoring programs in the Baltic Sea region. Based on whole fish concentrations, environmental status for cadmium and mercury in herring improved compared to assessments based on muscle or liver concentrations alone. 相似文献
14.
《Limnologica》2019
Lake Baikal is facing several environmental stressors, including climate change and nearshore eutrophication. To assess recent ecological changes in Lake Baikal and provide a baseline for future comparisons, we sampled spring plankton communities from the pelagic zone of the lake in 2016 and compared these data with unpublished and published historical information going back to 1990. In 2016, one pelagic long-term monitoring station was sampled in early spring (March) during ice cover and 21 long-term monitoring stations located throughout the lake were sampled in late spring (May-June). We measured water chemistry parameters at most stations and the abundance, taxonomic composition and biomass of bacteria, ciliates and phytoplankton at several locations in different areas of the lake. Biotic parameters from 2016 were compared with historical data, showing significant changes in the spring pelagic microbial community since the 1990s. We show increased quantities of small species, mixotrophic ciliates, and the appearance (or increasing number) of small coloured and colourless flagellates. We also show substantially decreased densities of formerly dominant heavily silicified diatoms such as Aulacoseira spp. Since 2007, Synedra acus subsp. radians, a smaller and weakly silicified diatom, has dominated the spring plankton of the lake. These results suggest that Lake Baikal’s pelagic plankton community may be changing, with climate likely playing a dominant role in these changes. 相似文献
15.
eDNA (environmental DNA)是指从环境样品（水体、土壤、沉积物、空气、混合物等）中提取的DNA,是各种生物的DNA混合物,区别于传统从单物种样品中提取的DNA。eDNA监测是指从环境样品中提取DNA,用物种特异性引物或特定DNA metabarcoding引物对其进行扩增测序、分类学分析、相对丰度分析、功能预测等,以监测环境中是否存在某特定物种,或者获得环境中物种组成、群落结构、生态功能等相关信息。eDNA监测主要应用在特定物种监测检出、生物多样性调查评估、群落结构和功能分析、生态系统过程分析评估等领域。eDNA监测可以应用在陆地、水体、空气、器物表面、生物（内）表面等任何有可能存在不确定DNA的场景。因为eDNA监测的非侵入性、灵敏检出、大类群检出、易标准化方法与结果、低人力物力时间成本、结果可核查等特点,未来很有希望发展成为一种常规的物种监测、群落功能预测、生态过程分析的方法,对象可涵盖所有生境条件下的所有生物类群。但要实现这个图景,需要从普遍性和特殊性层面完成eDNA监测技术链条中10个关键环节的技术标准化：样品重复数设计、采样时间设计、采样点设计、采样方法设... 相似文献
16.
The evidence for the wider effects of fishing on the marine ecosystem demands that we incorporate these considerations into our management of human activities. The consequences of the direct physical disturbance of the seabed caused by towed bottom-fishing gear have been studied extensively with over 100 manipulations reported in the peer-reviewed literature. The outcome of these studies varies according to the gear used and the habitat in which it was deployed. This variability in the response of different benthic systems concurs with established theoretical models of the response of community metrics to disturbance. Despite this powerful evidence, a recent FAO report wrongly concludes that the variability in the reported responses to fishing disturbance mean that no firm conclusion as to the effects of fishing disturbance can be made. This thesis is further supported (incorrectly) by the supposition that current benthic sampling methodologies are inadequate to demonstrate the effects of fishing disturbance on benthic systems. The present article addresses these two erroneous conclusions which may confuse non-experts and in particular policy-makers. 相似文献
17.
Bernard G. J. Massart Olav M. Kvalheim Fred Olav Libnau Karl I. Ugland Kjell Tjessem Karl Bryne 《Aquatic Sciences - Research Across Boundaries》1996,58(2):120-138
A method for environmental monitoring using benthic species profiles as input is developed in this work. The method, referred to as projective ordination, utilises local principal component modelling (SIMCA) to obtain a cross-validated model which spans the natural variation in a region around offshore oil-producing installations. The borderline between regions with disturbed and non-disturbed species communities is subsequently decided from the residual distribution. This distribution is used to design an approximate F-test for assessing whether a community at a particular sampling location is disturbed or not. If so, the nature of the disturbance is determined by projecting the data on the PC model.Projective ordination utilises information from previous surveys to define the permissible variation in species communities, i.e. the limit of the natural variation. In addition, the method is dynamic, in a sense that the sampling locations may vary from survey to survey.Furthermore, our analysis shows that the customary number of replicate samples per station can be reduced. Modelling with only four randomly chosen replicates out of the complete set of five for each sampling location, does not affect the model significantly. On the other hand, taking only 3 replicates into account leads to significant divergences.A model based on the 1990 and 1993 surveys at the Statfjord field is presented as an example of the technique. 相似文献
18.
Within the framework of ecosystem-based management, we focused on the use of seasonal closures as effective measures to minimise the degradation of benthic communities by trawling. These closures imply the complete cessation of trawling fleet activity and are commonly used in the Mediterranean to reduce the annual fishing effort, with the ultimate goal of effective resource management. In this study, we aimed to investigate how epibenthic communities respond to seasonal closures. The potential benefits of short-term annual closures in two Mediterranean fishing grounds were evaluated by analysing changes in community structure and composition that were linked to the closure. A decrease of faunal abundance was observed with the resumption of fishing activity after the closure at both fishing grounds. Remarkably, results indicated that some large and mobile fauna were able to respond to these closures. We concluded that the currently planned closures are too short to benefit benthic communities. 相似文献
19.
Susanne C. Schneider A.E. LawniczakJ. Picińska-Faltynowicz K. Szoszkiewicz 《Limnologica》2012,42(3):204-211
We analyzed species composition and abundance of macrophytes, diatoms and non-diatom benthic algae, water chemistry and habitat structure of 24 river sites in Poland, in order to better understand which parameters structure macrophyte and benthic algae communities. Community patterns for macrophytes and diatoms are most closely related, while macrophytes and non-diatom benthic algae have the weakest relationship. Environmental parameters best explaining community patterns are channel substrate parameters for non-diatom benthic algae, and a combination of channel substrate and river bank characteristics for submerged macrophytes, emergent macrophytes and diatoms. Among the organism groups investigated, the diatom community pattern is best correlated to the environmental data similarity matrix. We hypothesize that the results can be explained by the shorter generation time of diatoms compared to macrophytes, and by a higher dispersal rate of diatoms compared to macrophytes and non-diatom benthic algae. This has several practical consequences for bioindication: (1) Diatoms are usually the organism group most closely following environmental parameters, for both increasing and decreasing impact. (2) Since the biotic indices developed for the Water Framework Directive are meant to primarily indicate ecological changes, not water chemistry, the nature of diatoms to closely reflect water chemistry is not necessarily advantageous. (3) The applicability of macrophyte and probably also non-diatom benthic algae indices is more locally restricted, while diatom indices are applicable to greater areas. (4) In ecosystems which are subject to changing environmental conditions, differences in biotic indices between macrophytes, diatoms and non-diatom benthic algae are to be expected. These differences could provide information relating to ecosystem stability. (5) In stable ecosystems, analyzing one of the three organism groups “diatoms”, “non-diatom benthic algae” and “macrophytes” will be sufficient to characterize the quality element “macrophytes and phytobenthos”, as required by the Water Framework Directive. However, in ecosystems subject to increasing pressure, macrophytes likely will have a tendency to indicate “too good”, while in ecosystems subject to decreasing pressure, diatoms will have a tendency to indicate “too good”. 相似文献
20.
Alyssa M. Baxter Laura Johnson Todd Royer Laura G. Leff 《Aquatic Sciences - Research Across Boundaries》2013,75(2):275-284
In streams, benthic bacterial communities are integral to multiple aspects of ecosystem function, including carbon and nitrogen cycles. Variation both in terms of bacterial community structure (based on taxonomic and/or functional genes) and function can reveal potential drivers of spatiotemporal patterns in stream processes. In this study, the abundance and diversity of 16S rRNA genes and abundance of nosZ genes, encoding for nitrous oxide reductase, were related to denitrification and environmental conditions. Denitrification rates varied among the three streams examined, and within a given stream there were significant longitudinal differences. Likewise, bacterial community structure based on analysis of the 16S rRNA gene also differed significantly among streams. However, variation in denitrification rate was not well correlated with environmental or biological variables measured. In addition, relatively large numbers of denitrifiers occurred when denitrification rates were low. In conclusion, although the streams differed in environmental conditions as well as bacterial community structure, these differences did not explain much of the spatial variation in denitrification rates. 相似文献