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Spatial modeling of environmental vulnerability of marine finfish aquaculture using GIS-based neuro-fuzzy techniques Полный текст
2011
Navas, Juan Moreno | Telfer, Trevor C. | Ross, Lindsay G.
Spatial modeling of environmental vulnerability of marine finfish aquaculture using GIS-based neuro-fuzzy techniques Полный текст
2011
Navas, Juan Moreno | Telfer, Trevor C. | Ross, Lindsay G.
Combining GIS with neuro-fuzzy modeling has the advantage that expert scientific knowledge in coastal aquaculture activities can be incorporated into a geospatial model to classify areas particularly vulnerable to pollutants. Data on the physical environment and its suitability for aquaculture in an Irish fjard, which is host to a number of different aquaculture activities, were derived from a three-dimensional hydrodynamic and GIS models. Subsequent incorporation into environmental vulnerability models, based on neuro-fuzzy techniques, highlighted localities particularly vulnerable to aquaculture development. The models produced an overall classification accuracy of 85.71%, with a Kappa coefficient of agreement of 81%, and were sensitive to different input parameters. A statistical comparison between vulnerability scores and nitrogen concentrations in sediment associated with salmon cages showed good correlation. Neuro-fuzzy techniques within GIS modeling classify vulnerability of coastal regions appropriately and have a role in policy decisions for aquaculture site selection.
Показать больше [+] Меньше [-]Spatial modeling of environmental vulnerability of marine finfish aquaculture using GIS-based neuro-fuzzy techniques Полный текст
2014 | 2011
Navas, Jose M | Telfer, Trevor | Ross, Lindsay | Institute of Aquaculture Torre de la Sal | Institute of Aquaculture | Institute of Aquaculture | 0000-0003-1613-9026
Combining GIS with neuro-fuzzy modeling has the advantage that expert scientific knowledge in coastal aquaculture activities can be incorporated into a geospatial model to classify areas particularly vulnerable to pollutants. Data on the physical environment and its suitability for aquaculture in an Irish fjard, which is host to a number of different aquaculture activities, were derived from a three-dimensional hydrodynamic and GIS models. Subsequent incorporation into environmental vulnerability models, based on neuro-fuzzy techniques, highlighted localities particularly vulnerable to aquaculture development. The models produced an overall classification accuracy of 85.71%, with a Kappa coefficient of agreement of 81%, and were sensitive to different input parameters. A statistical comparison between vulnerability scores and nitrogen concentrations in sediment associated with salmon cages showed good correlation. Neuro-fuzzy techniques within GIS modeling classify vulnerability of coastal regions appropriately and have a role in policy decisions for aquaculture site selection.
Показать больше [+] Меньше [-]Effect of heavy oil on the development of the nervous system of floating and sinking teleost eggs Полный текст
2011
Irie, Kouta | Kawaguchi, Masahumi | Mizuno, Kaori | Song, Jun-Young | Nakayama, Kei | Kitamura, Shin-Ichi | Murakami, Yasunori
Heavy oil (HO) on the sea surface penetrates into fish eggs and prevents the normal morphogenesis. To identify the toxicological effects of HO in the context of the egg types, we performed exposure experiments using floating eggs and sinking eggs. In the course of development, HO-exposed embryos of floating eggs showed abnormal morphology, whereas early larva of the sinking eggs had almost normal morphology. However, the developing peripheral nervous system of sinking eggs showed abnormal projections. These findings suggest that HO exposed fishes have problems in the developing neurons, although they have no morphological malformations. Through these observations, we conclude that HO is strongly toxic to floating eggs in the morphogenesis, and also affect the neuron development in both floating and sinking eggs.
Показать больше [+] Меньше [-]Accumulation features of trace elements in mass-stranded harbor seals (Phoca vitulina) in the North Sea coast in 2002: The body distribution and association with growth and nutrition status Полный текст
2011
Agusa, Tetsuro | Yasugi, Shin-ya | Iida, Asami | Ikemoto, Tokutaka | Anan, Yasumi | Kuiken, Thijs | Osterhaus, Albert D.M.E. | Tanabe, Shinsuke | Iwata, Hisato
Body distribution and growth- and nutritional status-dependent accumulation of 21 trace elements were investigated in harbor seals (Phoca vitulina) stranded in the North Sea coast in 2002. Higher concentrations and burdens of Mn, Se, Mo, Ag, Sn, Hg, and Bi in the liver, Cd in the kidney, As in the blubber, and Co, Sr, and Ba in the bone were observed. Significant positive correlations of hepatic Se, Mo, Ag, Cd, Sn, Hg, Tl, and Bi with standard body length were found, while significant negative relationships were detected for Mn, As, Rb, Sr, and Sb in the liver. Concentrations of Co, Se, Sr, Sn, Hg, and Bi in the liver, V, Sr, Ag, Sn, and Hg in the kidney, V, Mn, Co, Rb, Sr, Sn, Ba, and Pb in the blubber increased with decreasing blubber thickness of harbor seals, indicating enrichment of these elements in the target tissue by emaciation.
Показать больше [+] Меньше [-]Influence of multiple stressors on the auto-remediation processes occurring in salt marshes Полный текст
2011
Sousa, Ana I. | Lillebø, Ana I. | Pardal, Miguel A. | Caçador, Isabel
Influence of multiple stressors on the auto-remediation processes occurring in salt marshes Полный текст
2011
Sousa, Ana I. | Lillebø, Ana I. | Pardal, Miguel A. | Caçador, Isabel
Due to increasing global population, salt marshes have been subjected to multiple stressors such as increasing nutrient loadings and historical contamination. In order to better understand how does the salt marsh plants auto-remediation capacity (phytoaccumulation of metals) is affected by cultural eutrophication, an experiment was performed under controlled conditions. Plants were exposure to equal metal concentrations (Zn, Cu, and Ni – micronutrients, and Cd – class B metal) simulating historical contamination and three different concentrations of nitrogen (nitrate) simulating steps of cultural eutrophication. According to our study, under the tested concentrations, cultural eutrophication does not seem to affect Zn, Cu and Ni phytoremediation of H. portulacoides, but the ecosystem service of Cd phytoremediation seems to be promoted. Nevertheless, Cd high toxicity and bioaccumulation should be taken into account, as well as the vulnerability of salt marsh ecosystems, whose reduction will have drastic consequences to the ecosystem health.
Показать больше [+] Меньше [-]Influence of multiple stressors on the auto-remediation processes occurring in salt marshes Полный текст
2011 | 1000
Sousa, A. I. | Lillebo, A. I. | Pardal, M. A. | Caçador, I.
Due to increasing global population, salt marshes have been subjected to multiple stressors such as increasing nutrient loadings and historical contamination. In order to better understand how does the salt marsh plants auto-remediation capacity (phytoaccumulation of metals) is affected by cultural eutrophication, an experiment was performed under controlled conditions. Plants were exposure to equal metal concentrations (Zn, Cu, and Ni – micronutrients, and Cd – class B metal) simulating historical contamination and three different concentrations of nitrogen (nitrate) simulating steps of cultural eutrophication. According to our study, under the tested concentrations, cultural eutrophication does not seem to affect Zn, Cu and Ni phytoremediation of H. portulacoides, but the ecosystem service of Cd phytoremediation seems to be promoted. Nevertheless, Cd high toxicity and bioaccumulation should be taken into account, as well as the vulnerability of salt marsh ecosystems, whose reduction will have drastic consequences to the ecosystem health.
Показать больше [+] Меньше [-]Small plastic debris changes water movement and heat transfer through beach sediments Полный текст
2011
Carson, Henry S. | Colbert, Steven L. | Kaylor, Matthew J. | McDermid, Karla J.
We investigated the physical properties of beaches contaminated with plastic fragments. We compared sediment cores from Hawai‘i Island’s Kamilo Beach, notable for plastic accumulation, to cores from a nearby beach. Compared to the nearby beach, Kamilo sediments contained more plastics (up to 30.2% by weight), were coarser-grained, and were more permeable (t-test, p<0.0001). 85% of the fragments were polyethylene, and 95% were concentrated in the top 15cm of the cores. We constructed artificial cores of standardized grain size and varying plastic-to-sediment ratios. Adding plastic significantly increased the permeability (ANOVA, p=0.002), which was partially attributed to the fragments increasing the mean grain size. Sediments with plastic warmed more slowly (16% maximum decrease in thermal diffusivity), and reached lower maximum temperatures (21% maximum increase in heat capacity). These changes have a variety of potential effects on beach organisms, including those with temperature-dependent sex-determination such as sea turtle eggs.
Показать больше [+] Меньше [-]Marine-derived filamentous fungi and their potential application for polycyclic aromatic hydrocarbon bioremediation Полный текст
2011
Passarini, Michel R.Z. | Rodrigues, Marili V.N. | Silva, Manuela da | Sette, Lara D.
Eight marine-derived fungi that were previously selected for their abilities to decolorize RBBR dye were subjected to pyrene and benzo[a]pyrene degradation. The fungus Aspergillus sclerotiorum CBMAI 849 showed the best performance with regard to pyrene (99.7%) and benzo[a]pyrene (76.6%) depletion after 8 and 16days, respectively. Substantial amounts of benzo[a]pyrene (>50.0%) depletion were also achieved by Mucor racemosus CBMAI 847. Therefore, these two fungal strains were subjected to metabolism evaluation using the HPLC-DAD-MS technique. The results showed that A. sclerotiorum CBMAI 849 and M. racemosus CBMAI 847 were able to metabolize pyrene to the corresponding pyrenylsulfate and were able to metabolize benzo[a]pyrene to benzo[a]pyrenylsulfate, suggesting that the mechanism of hydroxylation is mediated by a cytochrome P-450 monooxygenase, followed by conjugation with sulfate ions. Because these fungi were adapted to the marine environment, the strains that were used in the present study are considered to be attractive targets for the bioremediation of saline environments, such as ocean and marine sediments that are contaminated by PAHs.
Показать больше [+] Меньше [-]Comparison of Enterococcus density estimates in marine beach and bay samples by real-time polymerase chain reaction, membrane filtration and defined substrate testing Полный текст
2011
Ferretti, James A. | Tran, Hiep V. | Cosgrove, Elizabeth | Protonentis, John | Loftin, Virginia | Conklin, Carol S. | Grant, Robert N.
Currently, densities of Enterococcus in marine bathing beach samples are performed using conventional methods which require 24h to obtain results. Real-time PCR methods are available which can measure results in as little as 3h. The purpose of this study was to evaluate a more rapid test method for the determination of bacterial contamination in marine bathing beaches to better protect human health. The geometric mean of Enterococcus densities using Enterolert® defined substrate testing and membrane filtration ranged from 5.2 to 150MPN or CFU/100mL and corresponding qPCR results ranged from 6.6 to 1785CCE/100mL. The regression analysis of these results showed a positive correlation between qPCR and conventional tests with an overall correlation (r) of 0.71. qPCR was found to provide accurate and sensitive estimate of Enterococcus densities and has the potential to be used as a rapid test method for the quantification of Enterococcus in marine waters.
Показать больше [+] Меньше [-]Removal fluxes of Mn and Fe from the nearshore waters along the west coast of Taiwan Полный текст
2011
Wei, Ching-Ling | Jiann, Kuo-Tung | Wen, Liang-Saw | Tsai, Jing-Ru | Sheu, David D.
Dissolved and particulate Mn and Fe in the nearshore waters were determined at 27 stations along the west coast of Taiwan during 19–23 November 2004. The latitudinal distributions of Mn and Fe were very similar; however, the concentration in the dissolved phase was lower, whereas that in the particulate phase was higher in the northern regime. The higher percentage of Fe than Mn that was associated with particles resulted in a two-order of magnitude higher particle–water partition coefficient for Fe, Kd(Fe), than that for Mn, Kd(Mn). The removal fluxes of Mn and Fe could be estimated by multiplying the particulate ²³⁴Th removal flux with the Mn/²³⁴Th and Fe/²³⁴Th ratios in suspended particles, which ranged from 0.1 to 3.8mmolm⁻²d⁻¹ for Mn, and from 3.4 to 194.5mmolm⁻²d⁻¹ for Fe. Residence times ranged from 1 to 20days for Mn and Fe were estimated in the nearshore.
Показать больше [+] Меньше [-]Can patterns in benthic communities be explained by an environmental pressure index? Полный текст
2011
Oigman-Pszczol, Simone S. | Creed, Joel. C.
Many studies have assessed in unison specific biological attributes and certain environmental impacts but few studies have analyzed multiple biological variables and pressures from multiple sites at the same time. Our study’s goal was to quantify the major potential human pressures in the shallow subtidal rocky reefs along a tropical Atlantic coast; propose a relative environmental pressure index and investigate the relationships between environmental pressures, the benthic community and coral population attributes. The analysis of human pressures suggests that one-third of sites were under high or very high proportional stress. Sites with high human pressure had lower live cover, higher percent of recent mortality and density of Siderastrea stellata. These relations were species specific. The coral species S.stellata seemed to be the best indicator of present environmental stress. These findings demonstrate the need to include multiple species and stressors in monitoring programs designed to contribute to coastal management initiatives.
Показать больше [+] Меньше [-]Levels and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments from Lenga Estuary, central Chile Полный текст
2011
Pozo, Karla | Perra, Guido | Menchi, Valentina | Urrutia, Roberto | Parra, Oscar | Rudolph, Anny | Focardi, S. (Silvano)
The Lenga Estuary is a small brackish wetland located southwest of San Vicente Bay, Region VIII, Chile. Surface sediment from nine sites in the estuary were analysed for PAHs and compared to Sediment Quality Guidelines (SQG). Sediment samples were freeze dried and soxhlet extracted for 16h using DCM. Identification and quantification was carried out by HPLC. Organic carbon was also determined. Results showed total PAH concentrations ranged from 290 to 6118 (2025±1975)ngg⁻¹ d.w. (2025±1975). Results for organic carbon percentages ranged from 1% to 7%. Statistical analysis showed a significant positive correlation (Pearson test) between organic carbon percentage PAHs. Comparison of contaminant levels and international Sediment Quality Guidelines (SQG) (ERL and ER) suggested that sediment of the Lenga estuary did not show any ecotoxicologial risk for benthic organisms where high levels of PAHs were detected. Monitoring of this and other contaminants is recommended in Chile.
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