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1.
Flame retardants (PBDEs) in marine turtles, dugongs and seafood from Queensland, Australia 总被引：1，自引：1，他引：0
Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products. These compounds have been found to enter the marine environment where they have the potential to bioaccumulate in biota. Limited information is currently available concerning the levels of PBDEs in Australian marine wildlife. This study presents baseline information on PBDE levels in a variety of marine species from Queensland, Australia and considers the influence of species-specific factors on contaminant levels and tissue distribution in marine turtles. Overall, the PBDE levels measured in this study are relatively low compared to marine biota from the northern hemisphere, indicating low level input into the marine system of Queensland. This is in general agreement with global estimates which suggest low PBDE usage in Australia. Previous studies, however, have found relatively high PBDE levels in Australian human milk and sera. This discrepancy in contamination trends between terrestrial and marine biota suggests that future transport of PBDEs may occur to the marine system in Australia. 相似文献
2.
《Marine pollution bulletin》2009,58(6-12):409-418
Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products. These compounds have been found to enter the marine environment where they have the potential to bioaccumulate in biota. Limited information is currently available concerning the levels of PBDEs in Australian marine wildlife. This study presents baseline information on PBDE levels in a variety of marine species from Queensland, Australia and considers the influence of species-specific factors on contaminant levels and tissue distribution in marine turtles. Overall, the PBDE levels measured in this study are relatively low compared to marine biota from the northern hemisphere, indicating low level input into the marine system of Queensland. This is in general agreement with global estimates which suggest low PBDE usage in Australia. Previous studies, however, have found relatively high PBDE levels in Australian human milk and sera. This discrepancy in contamination trends between terrestrial and marine biota suggests that future transport of PBDEs may occur to the marine system in Australia. 相似文献
3.
Hylland K 《Marine pollution bulletin》2006,53(10-12):614-619
Coastal ecosystems are impacted by many stressors, of which chemicals are possibly not the most important. Chemicals differ from most other stressors such as eutrophication and hypersedimentation in the time scale-effects from the latter act on the scale of weeks or months, whereas effects from chemicals may take years to manifest themselves in population or community changes. There are four different approaches available to manage chemicals in marine ecosystems: target contaminant levels, target individual effects, target community impacts (biodiversity) and, finally, target processes. These four differ in the analytical methods available and the analyst's ability to separate effects from chemicals from other environmental factors and natural variation. There is furthermore, a need to develop a framework to integrate biological effects methods with risk assessment methodology. Such integration will improve the basis for risk-based assessment of chemicals. A problematic issue relevant to all aspects of environmental management are the interactions between chemicals, and between chemicals and eutrophication or sedimentation. There is a clear need for more knowledge about such interactions. 相似文献
4.
5.
The published literature on marine pollution monitoring research in South Africa from 1960 to present was evaluated. There has been a general decline in the number of papers from the 1980s and this can be linked to the absence of a marine pollution monitoring programme in South Africa. General trends observed were that contaminant exposure monitoring of metals predominates the research conducted to date. Monitoring results indicate that there has been a general decrease in metal concentrations in South African coastal waters and concentrations of metals and most organics in mussels are lower than in other industrialised nations. This is reflected in the general pristine nature and high biodiversity of the South African coastline. The establishment of a national marine pollution monitoring framework would stimulate marine pollution research. 相似文献
6.
The San Francisco Estuary Regional Monitoring Program initiated surveillance monitoring to identify previously unmonitored synthetic organic contaminants in the San Francisco Estuary. Organic extracts of water samples were analyzed using gas chromatography-mass spectrometry in full scan mode. The major contaminant classes identified in the samples were fire retardants, pesticides, personal care product ingredients, and plasticizers. Evidence from the literature suggests that some of these contaminants can persist in the environment, induce toxicity, and accumulate in marine biota and in higher food chain consumers. The major sources of these contaminants into the marine environment are the discharge of municipal and industrial wastewater effluents, urban stormwater, and agricultural runoff. As a proactive effort, it is suggested that surveillance studies be used routinely in monitoring programs to identify and prevent potential problem contaminants from harming the marine environment. 相似文献
7.
Ecological studies often attempt to link observed effects to multiple causal factors which may be operating simultaneously. Although in situ randomized experiments in which factor levels are controlled may be a powerful means for disentangling causal relationships, an experimental approach is not always feasible or even a desirable first step in the analysis, particularly when there is insufficient background knowledge of the system. In such cases, analysis of survey data, reflecting natural (co)variation in the putative causal factors and their direct and indirect effects, can be a practical and useful alternative to experiments. When set in the proper statistical framework, survey data can be used to assess whether a given factor has a detectable effect once the effect of other factors has been accounted for statistically (by partialling), and to estimate what proportion of the effect can be attributed to each factor (by variance decomposition). This analysis can help establish whether a particular causal model is consistent with the data at hand, and should be viewed as preliminary to a mechanistic approach, providing support and guidance for the investigation of more realistic variables. Here, we use three examples based on survey data from fish and invertebrate lacustrine communities to illustrate the application of partialling and variance decomposition in a multivariate setting. The first example shows that variation in the abundance and size structure of cladoceran taxa is still associated with fish species composition when potentially confounding effects of abiotic variables are accounted for by partialling. In the second and third examples, variance decomposition is used to determine the relative contribution of the environmental and spatial components to variation in the community structure of littoral zoobenthos and in the diet of a freshwater fish species.Contribution of the Group for Interuniversitary Research in Limnology (G.R.I.L.). 相似文献
8.
《Limnologica》2020
Freshwater systems have increasingly been subjected to a multitude of human pressures and the re-establishment of their ecological integrity is currently a major worldwide challenge. Expected future climate and socioeconomic changes will most probably further exacerbate such challenges. Modelling techniques may provide useful tools to help facing these demands, but their use is still limited within ecological quality assessment of water resources due to its technical complexity.We developed a Bayesian Belief Network (BBN) framework for modelling the ecological quality of rivers and streams in two European river basins located in two distinct European climatic regions: the Odense Fjord basin (Denmark) and the Sorraia basin (Portugal). This method enabled us to integrate different data sources into a single framework to model the effect of multiple stressors on several biological indicators of river water quality and, subsequently, on their ecological status. The BBN provided a simple interactive user interface with which we simulated combined climate and socioeconomic changes scenarios to assess their impacts on river ecological status.According to the resulting BBNs the scenarios demonstrated small impacts of climate and socioeconomic changes on the biological quality elements analysed. This yield a final ecological status similar to the baseline in the Odense case, and slightly worse in Sorraia. Since the present situation already depicts a high percentage of rivers and streams with moderate or worse ecological status in both basins, this means that many of them would not fulfil the Water Framework Directive target in the future. Results also showed that macrophytes and fish indices were mainly responsible for a non-desirable overall ecological status in Odense and Sorraia, respectively. The approach followed in this study is novel, since BBN modelling is used for the first time for assessing the ecological status of rivers and streams under future scenarios, using an ensemble of biological quality elements. An important advantage of this tool is that it may easily be updated with new knowledge on the nature of relationships already established in the BBN or even by introducing new causal links. By encompassing two case studies of very different characteristics, these BBN may be more easily adapted as decision-making tools for water management of other river basins. 相似文献
9.
Broad-scale mapping of marine benthos is required for marine resource management and conservation. This study combines textural derivatives based on bathymetry from multibeam hydroacoustics with underwater video observations to model and map sessile biota between 10- and 60-m water depth over 35 km2 in Point Addis Marine National Park (MNP), Vic., Australia. Classification tree models and maps were developed for macroalgae (all types, mixed red algae, Ecklonia, and rhodoliths) and sessile invertebrates (all types, sponges, and ascidians). Model accuracy was tested on 25% of the video observation dataset reserved from modelling. Models fit well for most macroalgae categories (correct classification rates of 67–84%), but are not as good for sessile invertebrate classes (correct classification rates of 57–62%). The poor fit of the sessile invertebrate models may be the combined result of grouping organisms with different environmental requirements and the effect of false absences recorded during video interpretation due to poor image quality. Probability maps, binary single-class maps, and multi-class maps supply spatially explicit, detailed information on the distribution of sessile benthic biota within the MNP and provide information at a landscape-scale for ecological investigations and marine management. 相似文献
10.
C. Michoski C. MirabitoC. Dawson D. WirasaetE.J. Kubatko J.J. Westerink 《Advances in water resources》2011,34(12):1666-1680
We present a family of p-enrichment schemes. These schemes may be separated into two basic classes: the first, called fixed tolerance schemes, rely on setting global scalar tolerances on the local regularity of the solution, and the second, called dioristic schemes, rely on time-evolving bounds on the local variation in the solution. Each class of p-enrichment scheme is further divided into two basic types. The first type (the Type I schemes) enrich along lines of maximal variation, striving to enhance stable solutions in “areas of highest interest.” The second type (the Type II schemes) enrich along lines of maximal regularity in order to maximize the stability of the enrichment process. Each of these schemes are tested on three model systems. The first is an academic exact system where basic analysis is easily performed. Then we discuss a pair of application model problems arising in coastal hydrology. The first being a contaminant transport model, which addresses a declinature problem for a contaminant plume with respect to a bay inlet setting. And the second, a multicomponent chemically reactive flow model of estuary eutrophication arising in the Gulf of Mexico. 相似文献
11.
Wither A Bamber R Colclough S Dyer K Elliott M Holmes P Jenner H Taylor C Turnpenny A 《Marine pollution bulletin》2012,64(8):1564-1579
The construction of a new generation of coastal power stations in the UK and other western European countries has highlighted the absence of robust standards for thermal discharges to transitional and coastal waters. The proposed discharge volumes are greater than hitherto, yet there has been little independent critical examination of their potential impact, whilst much of the existing guidance has been adapted from freshwater practice. This review considers the available knowledge on the tolerance and behaviour of fish and other marine biota to heated effluents. Appropriate ways are suggested of grouping fish species to reflect their sensitivity to thermal effects. The plethora of existing standards are considered and their validity assessed in a framework of predicted seawater temperature rise. Those species or groups of organisms most likely to be affected are identified and finally specific recommendations for thermal standards consistent with long term sustainability are proposed. 相似文献
12.
Chou CL Paon LA Moffatt JD Buzeta MI Fenton D Rutherford RJ 《Marine pollution bulletin》2004,48(9-10):884-893
The Musquash Estuary, one of the last ecologically intact estuaries in New Brunswick, has been designated an area of interest for a marine protected area (MPA) under the Oceans Act. The area has been assessed for contaminant background levels as required for establishing MPA environmental quality. American lobster (Homarus americanus), blue mussel (Mytilus edulis) and sediments were collected for assessing contaminant levels and distribution in the harbour. Levels of contaminants from the indicator species and the abiotic component have shown: (1) two extremes of high and low Cu and Ag in lobster from the area; and (2) lower metal levels in inner Musquash Harbour sediments and mussels than in those from the harbour mouth. These suggest that deposition of contaminants into the Musquash MPA site was due to transport of contaminants by coastal currents from upstream coastal industrial activities. This reverse trend with higher contaminant levels in the biotic and abiotic components in the outer harbour than in the inner harbour differs from a contaminated harbour and suggests that a contaminant exclusion zone should be considered for controlling contamination from nearby coastal and estuarine industrial sites to protect the sensitive habitats within the marine protected area. 相似文献
13.
P. P. Povinec I. Osvath M. S. Baxter S. Ballestra J. Carroll J. Gastaud I. Harms L. Huynh-Ngoc L. Liong Wee Kwong H. Pettersson 《Marine pollution bulletin》1997,35(7-12):235-241
IAEA-MEL participated in five expeditions to the Kara Sea with the aim of assessing the radiological consequences of dumped radioactive wastes in the Novaya Zemlya Bays and Trough. The programme included sampling, in-situ underwater investigations, laboratory analyses of water, sediment and biota samples, the development of a marine radioactivity database, modelling and radiological assessment, the organization of intercomparison exercises and the evaluation of distribution coefficients. Radiometric investigations have shown that no radiologically significant environmental contamination has occurred. Leakages which have led to locally increased levels of radionuclides in sediment have only been observed in Stepovoy and Abrosimov Bays. Computer modelling results suggest that only radiological effects on local and regional scales may be of importance. The global radiological impact of the disposals in the Arctic Seas will be negligible. 相似文献
14.
Jones MA Stauber J Apte S Simpson S Vicente-Beckett V Johnson R Duivenvoorden L 《Marine pollution bulletin》2005,51(1-4):448-458
Port Curtis is one of Australia's leading ports for which substantial industrial expansion is proposed over the next decade. However, there has been little attempt to date to assess the extent of contamination in waters, sediments and biota or to characterize the potential impacts of contaminants on aquatic biota. Contaminants of potential concern to biota and human health were investigated in the Port Curtis estuary using a screening-level risk assessment approach. Dissolved metal concentrations in waters were below [ANZECC/ARMCANZ, 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Vol. 1. The Guidelines, Australian and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand] trigger values, suggesting low risk of these contaminants. In sediments, arsenic, nickel and chromium concentrations exceeded interim sediment quality guidelines-low (ISQG-low), but were also high in the reference zone suggesting a natural origin. Historical data on naphthalene in Harbour sediments showed that it was also of potential concern. Bioaccumulation of contaminants in a range of biota was also used as an indicator of contaminant exposure. Biota were generally enriched in metals and tributyltin, which was also elevated in water and sediments. Although not unique to Port Curtis, mercury in barramundi was identified as a potential risk to human health. 相似文献
15.
《国际泥沙研究》2017,(4)
As global temperatures increase and dissolved oxygen(DO) content decreases in marine systems, indices assessing sediment DO content in benthic habitats are becoming increasingly useful. One such measure is the depth to the apparent redox potential discontinuity(aRPD), a transition of sediment color that serves as a relative measure of sediment DO content. We examined spatiotemporal variation of aRPD depth, and the nature of the relationships between aRPD depth and biotic(infauna and epibenthic predators) and abiotic variables(sediment properties), as well as the availability of resources(chlorophyll a concentration, and organic matter content) in the intertidal mudflats of the Bay of Fundy, Canada. aRPD depth varied significantly through space and time, and a combination of biotic(sessile and errant infauna, as well as epibenthic predators), and abiotic(exposure time of a plot, sediment particle size,penetrability, and water content) variables, as well as the availability of resources(sediment organic matter content, and chlorophyll a concentration) were correlated with aRPD depth. As such, knowledge of both biotic and abiotic variables are required for a holistic understanding of sediment DO conditions.Abiotic variables likely dictate a suite of potential aRPD depth conditions, while biota and resource availability, via bioturbation and respiration, strongly influence the observed aRPD depth. As DO conditions in marine systems will continue to change due to global climate change, elucidating these relationships are a key first step in predicting the influence decreasing DO content may have upon marine benthos. 相似文献
16.
Gerd Bürger 《水文研究》2017,31(22):4039-4042
A main obstacle to trend detection in time series occurs when they are autocorrelated. By reducing the effective sample size of a series, autocorrelation leads to decreased trend significance. Numerous recipes attempt to mitigate the effect of autocorrelation, either by adjusting for the reduced effective sample size or by removing the autocorrelated components of a series. This short note deals with the latter, also called prewhitening (PW). It is known that removal of autocorrelation also removes part of the trend, which may affect the signal‐to‐noise ratio. Two popular methods have dealt with this problem, the trend‐free prewhitening (TFPW) and the iterative prewhitening. Although it is generally accepted that both methods reduce the adverse effects of PW on the trend magnitude, corresponding effects on statistical significance have not been clearly stated for TFPW. Using a Monte Carlo approach, it is demonstrated that both methods entail quite different Type‐I error rates. The iterative prewhitening produces rates that are generally close to the nominal significance level. The TFPW, however, shows very high Type‐I error rates with increasing autocorrelation. The corresponding rate of false trend detections is unacceptable for applications, so that published trends based on TFPW need to be reassessed. 相似文献
17.
Gregory G. Lemaire Ursula S. McKnight Hanna Schulz Sandra Roost Poul L. Bjerg 《Ground Water Monitoring & Remediation》2020,40(2):40-51
Xenobiotic organic compounds can be discharged from contaminated groundwater inflow and may seep into streams from multiple pathways with very different dynamics, some not fully understood. In this study, we investigated the spatio-temporal variation of chlorinated ethenes discharging from a former industrial site (with two main contaminant sources, A and B) into a stream system in a heterogeneous clay till setting in eastern Denmark. The investigated reach and near-stream surroundings are representative of peri-urban settings, with a mix of high channel alteration and more natural stream environment. We therefore propose an approach for risk assessing impacts arising from such complex contamination patterns, accounting for potential spatio-temporal fluctuations and presence of multiple pathways. Our study revealed substantial variations in pathway contributions and overall contaminant mass discharge to the stream. Variable contaminant contributions arising from both groundwater seepage and urban drains were identified in the channelized part of the north stream, primarily from source A. Furthermore, variations in the hyporheic and shallow groundwater flows were found to enhance contaminant transport from source B. These processes result in an increase of the overall mass of contaminant discharged, correlating with the channels' flow. Thus, an in-stream control plane approach was found to be an effective method for integrating multiple and variable discharge contributions quantitatively, although information on specific contaminant sources is lost. This study highlights the complexity and variability of contaminant fluxes occurring at the interface between groundwater and peri-urban streams, and calls for the consideration of these variations when designing monitoring programs and remedial actions for contaminated sites with the potential to impact streams. 相似文献
18.
Assessing health of the Bay of Fundy--concepts and framework 总被引：8，自引：0，他引：8
Wells PG 《Marine pollution bulletin》2003,46(9):1059-1077
A discussion of health and ecosystem health (EH) concepts and a conceptual framework for assessing health of the Bay of Fundy are presented. The framework includes:Concepts--What is health? What is EH and marine ecosystem health (MEH)? How does EH relate to other closely related concepts and principles i.e. environmental quality (especially marine or MEQ), ecosystem integrity, and ecosystem sustainability?Importance--Why is EH important, and what are the linkages to people i.e. human health?Approaches and techniques--How do we monitor and measure EH, and in that context, ecosystem or ecological change? i.e. What are the monitoring approaches and tools? What is an appropriate set of EH indicators and indices for the Bay of Fundy and Gulf of Maine? At the present time, can we make unequivocal statements about the status and trends in EH measures of the Bay of Fundy? Do we have adequate guidelines, objectives and standards for assessing environmental quality and EH?Connecting with management needs--Do we have adequate mechanisms in place to address MEH, marine environmental quality (MEQ), and environmental sustainability in the Bay of Fundy? What is the role of periodic marine assessments (state of the marine environment reports) in this activity? What kinds of new directions and new ecosystem science should be given priority? What kinds of other new activities should be pursued?For the Bay of Fundy Coastal Forum at the recent 5th BOFEP Bay of Fundy Science Workshop (May 2002), five core questions flowing from the health framework served to initiate and focus the discussions:Current state--What is the present health or condition of the Bay of Fundy?Changes--Are conditions improving or deteriorating?Indicators--What kinds of indicators do we consider most useful in trying to answer these questions?Existing resources--Are there adequate resources (e.g. institutional, financial, scientific, regulatory) to protect or restore the health of the Bay?Needs--What kinds of new information and approaches do we need to protect the health of the Bay?The background information and ideas of this paper were intended to assist discussion at the Fundy workshop, and to help identify the next steps, both individual and collective, for assessing the health of the Bay of Fundy. 相似文献
19.
Mann–Kendall (MK) test for trend detection must be modified when the data are serially correlated, to prevent the detection of false trends. Various approaches are developed for this purpose, such as prewhitening, trend‐free prewhitening, variance correction and block bootstrap. Each method has its own Type I and Type II errors. In this study, the errors of block bootstrapping MK test are estimated by a simulation study and compared with other methods. Optimal block length that minimizes the Type I error is determined as function of sample size and autocorrelation coefficient. It is shown that the power of block bootstrapping MK test is comparable with those of other modified MK tests. These tests are applied to some annual streamflow series with trend recorded in Turkish rivers, and their powers are compared. A modified form of the trend‐free prewhitening procedure is proposed that has a smaller Type I error. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
20.
Fang Xiuqi Zhao Wanyi Zhang Chengpeng Zhang Diyang Wei Xueqiong Qiu Weili Ye Yu 《中国科学:地球科学(英文版)》2020,63(7):1013-1025
Land use-induced land cover change(LUCC) is an important anthropogenic driving force of global change that has influenced, and is still influencing, many aspects of regional and global environments. Accurate historical global land use/cover datasets are essential for a better understanding of the impacts of LUCC on global change. However, there are not only evident inconsistencies in current historical global land use/cover datasets, but inaccuracies in the data in these global dataset revealed by historical record-based reconstructed regional data throughout the world. A focus in historical LUCC and global change research relates to how the accuracy of historical global land cover datasets can be improved. A methodology for assessing the credibility of existing historical global land cover datasets that addresses temporal as well as spatial changes in the amount and distribution of land cover is therefore needed. Theoretically, the credibility of a global land cover dataset could be assessed by comparing similarities or differences in the data according to actual land cover data(the "true value"). However, it is extremely difficult to obtain historical evidence for assessing the credibility of historical global land cover datasets, which cannot be verified through field sampling like contemporary global land cover datasets. We proposed a methodological framework for assessing the credibility of global land cover datasets. Considering the types and characteristics of the available evidence used for assessments,we outlined four methodological approaches:(1) accuracy assessment based on regional quantitative reconstructed land cover data,(2) rationality assessment based on regional historical facts,(3) rationality assessment based on expertise, and(4) likelihood assessment based on the consistency of multiple datasets. These methods were illustrated through five case studies of credibility assessments of historical cropland cover data. This framework can also be applied in assessments of other land cover types, such as forest and grassland. 相似文献