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771.
J. L. F. Angeli T. H. Trevizani A. Ribeiro E. C. Machado R. C. L. Figueira B. Markert S. Fraenzle S. Wuenschmann 《Environmental monitoring and assessment》2013,185(10):8333-8342
Concentrations of arsenic and four additional trace elements (Cu, Cr, Ni, and Zn) were determined by inductively coupled plasma–optical emission spectrometry in the muscular tissue of the yellow catfish (Cathorops spixii) and the urutu catfish (Genidens genidens) from Paranaguá Estuarine Complex, Brazil (PEC). The PEC can be characterized by an environment of high ecological and economic importance in which preserved areas of rainforest and mangroves coexist with urban activities as ports and industries. The average concentrations (in milligram per kilogram dry weight) of elements in the muscle tissue of C. spixii are as follows: Zn (31), As (17), Cu (1.17), Cr (0.62), and Ni (0.28). Similar concentrations could be found in G. genidens with exception of As: Zn (36), As (4.78), Cu (1.14), Cr (0.51), and Ni (0.14). Fish from the geographic northern rural region (Guaraqueçaba–Benito) display higher As concentrations in the muscle tissues than fish found in the south-western (urban) part of the PEC. An international comparison of muscle tissue concentrations of trace elements in fish was made. Except for Ni in C. spixii, a tendency of decrease in element concentration with increasing size (age) of the fish could be observed. According to the National Health Surveillance Agency of Brazil, levels of Cr and As exceeded the permissible limits for seafood. An estimation of the provisional tolerable weekly intake of As was calculated with 109 % for C. spixii and with 29 % for G. genidens. 相似文献
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Steven?J.?CookeEmail authorView authors OrcID profile Eduardo?G.?Martins Daniel?P.?Struthers Lee?F.?G.?Gutowsky Michael?Power Susan?E.?Doka John?M.?Dettmers David?A.?Crook Martyn?C.?Lucas Christopher?M.?Holbrook Charles?C.?Krueger 《Environmental monitoring and assessment》2016,188(4):239
Freshwater fish move vertically and horizontally through the aquatic landscape for a variety of reasons, such as to find and exploit patchy resources or to locate essential habitats (e.g., for spawning). Inherent challenges exist with the assessment of fish populations because they are moving targets. We submit that quantifying and describing the spatial ecology of fish and their habitat is an important component of freshwater fishery assessment and management. With a growing number of tools available for studying the spatial ecology of fishes (e.g., telemetry, population genetics, hydroacoustics, otolith microchemistry, stable isotope analysis), new knowledge can now be generated and incorporated into biological assessment and fishery management. For example, knowing when, where, and how to deploy assessment gears is essential to inform, refine, or calibrate assessment protocols. Such information is also useful for quantifying or avoiding bycatch of imperiled species. Knowledge of habitat connectivity and usage can identify critically important migration corridors and habitats and can be used to improve our understanding of variables that influence spatial structuring of fish populations. Similarly, demographic processes are partly driven by the behavior of fish and mediated by environmental drivers. Information on these processes is critical to the development and application of realistic population dynamics models. Collectively, biological assessment, when informed by knowledge of spatial ecology, can provide managers with the ability to understand how and when fish and their habitats may be exposed to different threats. Naturally, this knowledge helps to better evaluate or develop strategies to protect the long-term viability of fishery production. Failure to understand the spatial ecology of fishes and to incorporate spatiotemporal data can bias population assessments and forecasts and potentially lead to ineffective or counterproductive management actions. 相似文献
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I. Panagiotoulias F. Botsou H. Kaberi A. P. Karageorgis M. Scoullos 《Environmental monitoring and assessment》2017,189(11):598
In order to document the impact of Best Available Techniques (BAT) and implementation of regulation on the improvement of the coastal marine environment state, we examined the case of a representative steel mill located at the Gulf of Elefsis (Greece). The evaluation of metal pollution was based on the analysis of major and trace elements, organic carbon, magnetic properties, and sediment accumulation rates, in sediment cores obtained from the vicinity of the plant. The analytical data are discussed in relation to steel production, changes of production routes, and adoption of BAT introduced in order to fulfill EU and national legislation. The results show that the input of pollutants to sediments and the degree of contamination were reduced by approximately 40–70% in the decade 2003–2015 in comparison to the periods of high discharges (1963–2002), whereas the toxicity risks from “high-to-extremely high” were reduced to “medium-to-high.” 相似文献
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J. F. Jasonsmith B. C. T. Macdonald I. White 《Environmental monitoring and assessment》2017,189(4):188
Wybong Creek discharges salts into the agriculturally and industrially important Hunter River in New South Wales, Australia. Abrupt increases in salinity occur periodically in the mid-Wybong Creek catchment. In order to understand the processes which cause these abrupt increases, changes in surface and groundwater were investigated. It is shown that salinity increases can be attributed to highly discrete groundwater discharge directly into the river from below. Hourly electrical conductivity data measured in the river showed regular, diurnal electrical conductivity fluctuations of up to 350 μS cm?1. These fluctuations could not be attributed to barometric pressure, temperature, or evapotranspiration. Instead, a similar periodicity in surface water electrical conductivity and groundwater height in nearby groundwater wells was found. Fluctuations were of similar periodicity to the orthotides which cause fluctuations in surface water height and are induced by Earth tides. The geology in the mid-catchment area indicates conditions are optimal for Earth tides to impact groundwater. The reporting of orthotidal changes in water chemistry in this article is believed to be the first of its kind in the scientific literature, with the large fluctuations noted having important implications for water monitoring and management in the catchment. Further research investigating Earth-tide-induced phases of groundwater heights will better constrain the relationships between surface water chemistry and groundwater height. 相似文献