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1.
The effect of tri-n-butyl tin (TBT) on an intact marine sediment community after five months exposure was investigated. Changes in the structure of macro- and meiofauna communities were determined, as well as the functional diversity of the microbial community using BIOLOG microplates for Gram negative bacteria. Development of tolerance in the microbial community was investigated using Pollution Induced Community Tolerance (PICT) experiments with fluxes of nutrients as effect indicators. TBT affected the structure and recruitment of the macro- and meiofauna at nominal additions of 30-137 micromol TBT/m2 sediment. Number of species, diversity, biomass and community similarity was reduced at these concentrations compared to control. Species that molt seemed to be the most tolerant since they were predominant in boxes that had received the highest TBT addition and echinoderms were the most sensitive species. Renewed addition of TBT in PICT experiments with sediment from each boxcosm showed that TBT had an effect on individual nutrient fluxes from all sediments. Analyses of the flux patterns revealed a memory of previous TBT exposure, either due to induced tolerance or other community conditioning.  相似文献   

2.
The effects of prolonged exposure to low concentrations of herbicides on tropical periphyton (biofilm) communities are largely unknown. Tropical estuarine biofilms established in microcosms were therefore exposed to diuron (photosystem-II-inhibitor) at 2-16μg L(-1) for 4 weeks. The biofilms, consisting of diatoms, filamentous brown algae and cyanobacteria, developed a tolerance to diuron during this period as measured by Phyto-PAM fluorometry. Microscopy and pigment analysis revealed that this decrease in sensitivity was accompanied by a shift in species composition towards communities dominated by diatoms. The combination of techniques enabled the first identification of pollution-induced community tolerance (PICT) in tropical estuarine periphyton in response to chronic herbicide exposures. Community composition changed compared to controls at environmentally relevant concentrations of 1.6μg L(-1), while development of PICT was evident at 6.5μg L(-1) diuron, with no recovery (over 2 weeks) in uncontaminated water, indicating chronic pollution induced shifts in community structure.  相似文献   

3.
The detection of urinary polycyclic aromatic hydrocarbon (PAH) metabolites by fluorescence spectrophotometry is particularly effective as a practical means to assess PAH exposure in decapod crabs. However, the practical application of this technique has thus far only been tested for the European shore crab (Carcinus maenas) and only a few field studies have been conducted in heavily polluted areas. The present study evaluated the adaptability of this method as a rapid, cost-effective and non-destructive biomonitoring tool for the New Zealand crab species, Macrophthalmus hirtipes (stalk-eyed mud crab). A field gradient could be detected among the sites and different input sources of PAH contamination could be discerned through the differentiation of pyrogenic and petrogenic PAH signatures. The present study shows that the fluorescence screening method is sensitive to relatively low levels of PAH contamination and more broadly applicable to smaller crab species than C. maenas, for which the technique was developed.  相似文献   

4.
McMurdo Station is the United States Antarctic Research Program's (USARP) centre for scientific and logistical support for most of the continent and is the largest settlement in Antarctica. Over 30 years of human presence with shipping, air-transport, scientific, and municipal activities have resulted in severe but localized nearshore marine benthic pollution. This review will summarize the results of 3 years of research which has documented concentrations of chemical contaminants, changes in community patterns, and the toxicity of sediments to invertebrate species and infaunal communities. The primary contaminants are petroleum hydrocarbons in the sediments of Winter Quarters Bay, the site of shipping activities and a former dumpsite. Total hydrocarbon levels in sediments in Winter Quarters Bay were comparable to the most polluted harbours in temperate latitudes. However, a steep gradient of pollution existed: stations less than 1 km away were nearly pristine. Benthic invertebrate communities changed dramatically along this contamination gradient. The results of both field and laboratory bioassay experiments with contaminated sediments found that biological changes observed in benthic communities around McMurdo Station were most likely caused by hydrocarbons, PCBs, and PCTs. A primary goal of polar pollution research is to determine the response and tolerance of Antarctic biota to physical and chemical anthropogenic disturbance, and the mitigation of negative effects. To this end, future work should include continued monitoring of changes in chemical and community patterns, studies of the physiological responses of Antarctic invertebrates to chemical contamination, and further comparisons of anthropogenic and natural disturbances to benthic communities.  相似文献   

5.
Sediment quality has been evaluated in a variety of ways since the early 1990s in studies from Europe. In South Korea, most studies have used an indicator value for benthic macroinvertebrates based on water quality, not sediment quality. To date, few studies have examined the biological integrity of benthic macroinvertebrate communities in South Korea. In the current study, the tolerance valency and value in samples and the indicator weight values were measured for 43 benthic macroinvertebrate taxa from 73 sampling units in South Korea from 2014 to 2016. Total organic carbon, the amount of heavy metals, and total ammonia nitrogen were analyzed. The average grade for each pollutant was used as the sediment quality index. A benthic macroinvertebrates sediment index was developed for bioassessment of freshwater sediment. The benthic macroinvertebrates sediment index, which is based on the relative frequency of occurrence of macroinvertebrates, was highly correlated with pollution levels in the sediment. This index can be used in the field to assess the contamination of freshwater sediment. As the sample size was small in the current study and there were taxonomic limitations of Chironomidae larvae, further research is needed to improve the reliability of the benthic macroinvertebrates sediment index.  相似文献   

6.
The toxicity of a number of new anti-fouling paints, claimed to function by physical means and not by leakage of toxic substances, have been tested on two common organisms in the Baltic Sea, i.e., the red macro alga Ceramium tenuicorne and the copepod Nitocra spinipes. In order to compare the toxicity between the paints a ranking system was developed based on the EC50- and LC50-values. The results showed a wide span in toxicity with the most toxic paints ranked 160 times more toxic than the ones ranked least toxic.

Also, TBT, irgarol and diuron, which have been used as active ingredients in traditional anti-fouling paints, were used to evaluate the sensitivity of the two test organisms. The results showed that the test organisms were equally sensitive to the substances as similar organisms in earlier studies.

In conclusion, the ranking system presented in this study permits ranking and comparison of total toxicity of complex mixtures.  相似文献   


7.
Heavy metal contamination levels are generally higher in estuaries than in the open sea. Some estuaries, the Seine estuary for example, have particularly high pollution levels of metals, yet continue to support a very high benthic biomass and remain quite productive. Measurements of sediment contamination are highly variable due to diverse chemical analysis methods, sediments origin and sources of contaminants found in the estuaries. Salinity appears to be the principal factor controlling contaminant distribution in the sediment and the overlying and/or interstitial waters; it also affects the bioavailability of contaminants in estuarine sediments. Of course, the response to contaminants varies greatly among species and assemblages. Trace metals explain only a small part of the variation in benthic community structure. Some species, such as the shrimp Crangon crangon, appears vulnerable to metal pollution, while other species, such as Scrobicularia plana, are able to tolerate quite high levels of cadmium in their tissue. This paper demonstrates the wide variability of benthic responses to contamination, which is probably due to the high spatio-temporal heterogeneity of the estuary. To reduce the problems due the heterogeneity and variability observed to date in the available results, it will be necessary to encourage integrated estuarine studies, in which sedimentologists, chemists, and biologists work together on the same campaigns at the same sites.  相似文献   

8.
Habitat-forming organisms are frequently used as biomonitors in marine environments due to a widespread ability to accumulate toxic contaminants. Few studies, however, have considered the consequences of these accumulated contaminants on the abundant and diverse fauna associated with these habitats. In this review, we summarize research which has investigated the contamination of biogenic habitats (including seagrasses, macroalgae, ascidians, sponges and bivalve reefs) and the impact of this contamination on the habitat use, feeding behaviour and survival of associated epifauna. In many cases, ecological impacts upon epifauna are not simply predicted by levels of contamination in their habitat, but are determined by the foraging, feeding and reproductive behaviours of the inhabiting organisms. Thus, a thorough understanding of these ecological processes is essential in order to understand the effects of contaminants upon epifaunal communities. The scope of biomonitoring studies which assess the contamination of biogenic habitats should be expanded to include an assessment of potential effects upon associated epifauna. When combined with manipulative field experiments such an approach would greatly assist in our understanding of indirect effects of contaminants in these important benthic habitats.  相似文献   

9.
《Marine pollution bulletin》2013,77(1-2):360-364
The herbicide irgarol 1051 is commonly used on ship hulls to prevent growth of algae, but as a component of self-eroding paints it can also spread in the surrounding waters and affect non-target organisms. The effect of irgarol on settlement and growth of zoospores from the marine macro algae Ulva lactuca from the Gullmar fjord on the Swedish west coast was investigated in the present study. The zoospores were allowed to settle and grow in the presence of irgarol, but neither settlement – nor growth inhibition was observed at concentrations of up to 2000 nmol l−1. This is between 10 and 100 times higher than effect concentrations reported earlier for algae. Irgarol also induced the greening effect (4-fold increase in chlorophyll a content) in the settled zoospore/germling population, typical for photosystem II inhibitors like irgarol. This study support previous findings that irgarol constitutes a selection pressure in the marine environment.  相似文献   

10.
Benthic diatoms are often used for assessing environmental conditions, such as water quality and habitat conditions in stream and river systems. Although laboratory experiments have shown that each diatom species have different levels of tolerance to different stressors, few studies have been conducted in laboratory settings that analyze the responses of the diatom assemblage to the effects of multiple simultaneous variables. The aim of this study was to evaluate some structural responses (such as species composition and diversity) of the diatom assemblage on a short time scale to the effects of the simultaneous increase in four variables that are directly linked to the environmental changes affecting the Pampean streams: turbidity, nutrients (phosphorous and nitrogen), water velocity and temperature. To this end we conducted a five-week laboratory experiment using artificial channels where we simulated two environmental conditions (LOW and HIGH) employing epipelic biofilm from a mesotrophic stream. The results obtained in the experiment show that the structure of the diatom assemblage in the epipelic biofilm is affected by the simultaneous modification of temperature, water velocity, nutrient concentration and turbidity. These modifications in the assemblage included moderate decreases in diversity, small decreases in the proportion of species sensitive to eutrophication and saprobity, moderate increases in the IDP (Pampean Diatom Index) values and moderate changes in the percentages of the stalked growth-forms. The relative abundance of species such as Luticola mutica, Navicula cryptocephala and Navicula lanceolata were negatively affected by both treatments; other species such as Planothidium lanceolatum, Caloneis bacillum, Encyonema minutum, Humidophila contenta, Luticola kotschyi, Nitzschia amphibia, Navicula veneta, Pinnularia subcapitata var. subcapitata were positively affected by the HIGH treatment; and Nitzschia fonticola was positively affected by both treatments. The results suggest that, in the very short term of the bioassay conducted, the diatom assemblage can modify its structure to respond in a sensitive manner to the abrupt changes in multiple physical–chemical variables.  相似文献   

11.
The Gulf of Thailand has been a major marine resource for Thai people for a long time. However, recent industrialization and community development have exerted considerable stress on the marine environments and provoked habitat degradation. The following pollution problems in the Gulf have been prioritized and are discussed in details: (1) Untreated municipal and industrial waste water are considered to be the most serious problems of the country due to limited waste water treatment facilities in the area. (2) Eutrophication is an emerging problem in the gulf of Thailand. Fortunately, the major species of phytoplankton that have been reported as the cause of red tide phenomena were non-toxic species such as Noctiluca sp. and Trichodesmium sp. (3) Few problems have been documented from trace metals contamination in the Gulf of Thailand and public health threat from seafood contamination does not appear to be significant yet. (4) Petroleum hydrocarbon residue contamination is not a problem, although a few spills from small oil tankers have been recorded. A rapid decrease in mangrove forest, coral reefs, and fisheries resources due to mismanagement is also discussed.  相似文献   

12.
A review of published literature on the sensitivity of corals to turbidity and sedimentation is presented, with an emphasis on the effects of dredging. The risks and severity of impact from dredging (and other sediment disturbances) on corals are primarily related to the intensity, duration and frequency of exposure to increased turbidity and sedimentation. The sensitivity of a coral reef to dredging impacts and its ability to recover depend on the antecedent ecological conditions of the reef, its resilience and the ambient conditions normally experienced. Effects of sediment stress have so far been investigated in 89 coral species (～10% of all known reef-building corals). Results of these investigations have provided a generic understanding of tolerance levels, response mechanisms, adaptations and threshold levels of corals to the effects of natural and anthropogenic sediment disturbances. Coral polyps undergo stress from high suspended-sediment concentrations and the subsequent effects on light attenuation which affect their algal symbionts. Minimum light requirements of corals range from <1% to as much as 60% of surface irradiance. Reported tolerance limits of coral reef systems for chronic suspended-sediment concentrations range from <10mgL(-1) in pristine offshore reef areas to >100mgL(-1) in marginal nearshore reefs. Some individual coral species can tolerate short-term exposure (days) to suspended-sediment concentrations as high as 1000mgL(-1) while others show mortality after exposure (weeks) to concentrations as low as 30mgL(-1). The duration that corals can survive high turbidities ranges from several days (sensitive species) to at least 5-6weeks (tolerant species). Increased sedimentation can cause smothering and burial of coral polyps, shading, tissue necrosis and population explosions of bacteria in coral mucus. Fine sediments tend to have greater effects on corals than coarse sediments. Turbidity and sedimentation also reduce the recruitment, survival and settlement of coral larvae. Maximum sedimentation rates that can be tolerated by different corals range from <10mgcm(-2)d(-1) to >400mgcm(-2)d(-1). The durations that corals can survive high sedimentation rates range from <24h for sensitive species to a few weeks (>4weeks of high sedimentation or >14days complete burial) for very tolerant species. Hypotheses to explain substantial differences in sensitivity between different coral species include the growth form of coral colonies and the size of the coral polyp or calyx. The validity of these hypotheses was tested on the basis of 77 published studies on the effects of turbidity and sedimentation on 89 coral species. The results of this analysis reveal a significant relationship of coral sensitivity to turbidity and sedimentation with growth form, but not with calyx size. Some of the variation in sensitivities reported in the literature may have been caused by differences in the type and particle size of sediments applied in experiments. The ability of many corals (in varying degrees) to actively reject sediment through polyp inflation, mucus production, ciliary and tentacular action (at considerable energetic cost), as well as intraspecific morphological variation and the mobility of free-living mushroom corals, further contribute to the observed differences. Given the wide range of sensitivity levels among coral species and in baseline water quality conditions among reefs, meaningful criteria to limit the extent and turbidity of dredging plumes and their effects on corals will always require site-specific evaluations, taking into account the species assemblage present at the site and the natural variability of local background turbidity and sedimentation.  相似文献   

13.
New concepts in ecological risk assessment: where do we go from here?   总被引：10，自引：0，他引：10  
Through the use of safety factors, the use of single-species test data has been adequate for use in protective hazard assessments and criteria setting but, because hazard quotients do not consider the presence of multiple species each with a particular sensitivity or the interactions that can occur between these species in a functioning community, they are ill-suited to environmental risk assessment. Significant functional redundancy occurs in most ecosystems but this is poorly considered in single-species tests conducted under laboratory conditions. A significant advance in effects assessment was the use of the microcosm as a unit within which to test interacting populations of organisms. The microcosm has allowed the measurement of the environmental effect measures such as the NOAEC(community) under laboratory or field conditions and the application of this and other similarly derived measures to ecological risk assessment (ERA). More recently, distributions of single-species laboratory test data have been used for criteria setting and, combined with distributions of exposure concentrations, for risk assessment. Distributions of species sensitivity values have been used in an a priori way for setting environmental quality criteria such as the final acute value (FAV) derived for water quality criteria. Similar distributional approaches have been combined with modeled or measured concentrations to produce estimates of the joint probability of a single species being affected or that a proportion of organisms in a community will be impacted in a posteriori risk assessments. These techniques have not been widely applied for risk assessment of dredged materials, however, with appropriate consideration of bioavailability and spatial and nature of the data these techniques can be applied to soils and sediments.  相似文献   

14.
We examined Cu contamination effects on macrobenthic communities and Cu concentration in invertebrates within Shelter Island Yacht Basin, San Diego Bay, California. Results indicate that at some sites, Cu in sediment has exceeded a threshold for “self defense” mechanisms and highlight the potential negative impacts on benthic faunal communities where Cu accumulates and persists in sediments. At sites with elevated Cu levels in sediment, macrobenthic communities were not only less diverse but also their total biomass and body size (individual biomass) were reduced compared to sites with lower Cu. Cu concentration in tissue varied between species and within the same species, reflecting differing abilities to “regulate” their body load. The spatial complexity of Cu effects in a small marina such as SIYB emphasizes that sediment-quality criteria based solely on laboratory experiments should be used with caution, as they do not necessarily reflect the condition at the community and ecosystem levels.  相似文献   

15.
Deriving sediment quality guidelines (SQGs) for marine sediments is a difficult task. It will often be a trade off between reproducibility and relevance. One of the fundamental questions in ecotoxicology is to decide what one should measure to detect response in ecosystems exposed to human disturbance. In this paper we use field data to estimate threshold levels eliciting effects on soft bottom macrobenthos collected at different sediment types and depths on the Norwegian Continental Shelf and test these against natural levels occurring levels in reference conditions. SQGs are presented from multivariate analyses based on 121 gradients (represented with Ba, THC, Cd, Cu, Pb and Zn) incorporating more than 2000 species. Clear clusters with slightly disturbed communities related to contamination loadings were evident in 35% of the gradients. We found large variations in naturally occurring contamination concentrations and in the threshold levels electing effects on the fauna at different sediment types and depths. For example, an increase in depth of only 100 m can triple the Cu and Zn concentrations that elicit effects. Lowest background and threshold levels were found in shallow, sandy sediment. Our results suggest that current SQGs are too high. We hypothesised that setting a SQG of 4-times background concentrations will give sufficient protection for the fauna from metal contamination. The overall background concentration eliciting effects on metal was 3.6x.  相似文献   

16.
Indigenous organisms can be used as bioindicators for effects of contaminants, but no such bioindicator has been established for Arctic areas. Orchomenella pinguis is a benthic amphipod, ubiquitous in the Arctic and can be found in high numbers. We collected O. pinguis at sites with different contamination levels. Population characteristics (body length distribution, average dry weight and amphipod organic content) were related to sediment contaminant concentrations, in order to identify suitable endpoints for using this species as a bioindicator. We show that O. pinguis was prevalent in both clean and contaminated areas, easy to sample and that its population characteristics could be linked to both contamination and sediment organic content. We suggest that O. pinguis is a suitable bioindicator for the Arctic, but that endpoints such as reproductive effects and phenotypic and genotypic responses are needed together with population characteristics to assess impacts of contamination.  相似文献   

17.
New biocide-free anti-fouling paints are toxic   总被引：1，自引：0，他引：1  
A number of new anti-fouling paints claimed to be more friendly to the environment, have entered the market since prohibition of biocide containing paints have been enforced in many areas. Leakage waters from five new anti-fouling paints were tested for toxic effects to the macro algae Ceramium tenuicorne and Ceramium strictum and to the crustacean Nitocra spinipes. A banned copper and irgarol 1051 containing anti-fouling paint was used as reference. Five of the six paints tested were toxic to all or some of the organisms after two weeks of leakage with EC50 ranging from 0.08 to around 2% leakage water and LC50 ranging from 1.1% to 88%. The toxicity of leakage water from these paints was still high after 16 weeks. We conclude that these paints contain substances toxic to common organisms in the coastal Baltic ecosystem. A silicone based paint did not exhibit toxic effects to the two organisms. We recommend that biological tests should be used to identify the most harmful products before they are released on the market.  相似文献   

18.
The ECOMAN was initiated in 2001 by the University of Plymouth, UK, Plymouth Marine Laboratory and the Department of the Environment, Fisheries and Rural Affairs (DEFRA) to address the need for more pragmatic assessment techniques linking environmental degradation with its causes. The primary aim of the project was to develop an evidence-based approach in which suites of easy-to-use, cost-effective and environmentally valid biological responses (biomarkers) could be used together to assess the health of coastal systems through the general condition of individuals. A range of sub-lethal endpoints, chosen to reflect successive levels of biological organisation (molecular, cellular, physiological), was evaluated in common coastal organisms showing different feeding types (filter feeding, grazing, predation) and habitat requirements (estuary, rocky shore). Initially, the suite of biomarkers was used in laboratory studies to determine the relative sensitivities of key species within different functional groups to common contaminants. These results were then validated in field studies performed in a range of ecosystems exhibiting different degrees/signatures of contamination. Here, an example is provided of a field study in the Humber Estuary, UK, which illustrates how multivariate statistical analysis can be used to identify patterns of response to discriminate between contaminated and clean sites. The use of a holistic, integrated approach of this kind is advocated as a practical means of assessing the impact of chemical contamination on organismal health and of ranking the status of marine ecosystems.  相似文献   

19.
大型底栖动物群落结构与水环境因子具有较强的响应关系,为了量化分析大型底栖动物群落水环境因子适宜状态以及响应关系,在太子河进行3次流域水生态调查,共获得136个站位的生态数据,通过筛选得到水环境驱动因子,并利用加权平均回归分析和临界点指示类群分析的方法,探究大型底栖动物群落物种、不同多样性水平以及功能摄食类群水环境驱动因子的最适值和阈值.结果显示,显著影响大型底栖动物群落结构的水环境因子是溶解氧、电导率、总氮.大型底栖动物敏感种的溶解氧最适值较高,耐污种较低;敏感种的电导率和总氮最适值较低,耐污种较高;大型底栖动物群落多样性水平Shannon-Wiener指数(0-1]区间的溶解氧最适值最低,(3-4]区间的溶解氧最适值最高,各Shannon-Wiener指数区间电导率和总氮最适值排序为:(0-1]区间(1-2]区间(2-3]区间(3-4]区间;在5个功能摄食类群中溶解氧最适值最高和最低分别为撕食者和直接收集者,电导率最适值最高和最低分别为直接收集者和过滤收集者,总氮最适值最高和最低分别为直接收集者和刮食者.大型底栖动物敏感种的溶解氧阈值高于耐污种类群与其他物种,而敏感种的电导率和总氮阈值低于耐污种和其他物种;大型底栖动物群落多样性水平Shannon-Wiener指数(0-1]区间与溶解氧阈值呈负响应关系,而与电导率和总氮阈值呈正响应关系,(1-2]区间、(2-3]区间、(3-4]区间与溶解氧阈值呈正响应关系,而与电导率和总氮阈值呈负响应关系;溶解氧指示的大型底栖动物功能摄食类群为撕食者,且呈正响应关系,而电导率和总氮指示的功能摄食类群都包括过滤收集者、刮食者、撕食者,且呈负响应关系,其中刮食者的电导率和总氮阈值均最高.研究表明,通过分析大型底栖动物群落水环境因子的最适值和阈值,能以数据的形式量化反映大型底栖动物群落与河流水环境因子的响应关系,对河流生态环境的保护和修复具有重要的指导意义.  相似文献   

20.
《Marine pollution bulletin》2009,58(6-12):221-235
Deriving sediment quality guidelines (SQGs) for marine sediments is a difficult task. It will often be a trade off between reproducibility and relevance. One of the fundamental questions in ecotoxicology is to decide what one should measure to detect response in ecosystems exposed to human disturbance. In this paper we use field data to estimate threshold levels eliciting effects on soft bottom macrobenthos collected at different sediment types and depths on the Norwegian Continental Shelf and test these against natural levels occurring levels in reference conditions. SQGs are presented from multivariate analyses based on 121 gradients (represented with Ba, THC, Cd, Cu, Pb and Zn) incorporating more than 2000 species. Clear clusters with slightly disturbed communities related to contamination loadings were evident in 35% of the gradients. We found large variations in naturally occurring contamination concentrations and in the threshold levels electing effects on the fauna at different sediment types and depths. For example, an increase in depth of only 100 m can triple the Cu and Zn concentrations that elicit effects. Lowest background and threshold levels were found in shallow, sandy sediment. Our results suggest that current SQGs are too high. We hypothesised that setting a SQG of 4-times background concentrations will give sufficient protection for the fauna from metal contamination. The overall background concentration eliciting effects on metal was 3.6×.  相似文献   

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