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Economic losses from marine pollution
2001
Ofiara, Douglas D. | Seneca, Joseph J.
Marine pollution causes significant damage to fisheries and other economically productive uses of the ocean. The value of that damage can be quantified by economists, but the meanings of those valuations and how they are derived are often obscure to noneconomists. Economic Losses from Marine Pollution brings a fuller understanding of the variety and extent of marine losses and how they are assessed to scientists, lawyers, and environmentalists by systematically identifying and classifying marine losses and relating them to models and methods of economic valuation. The authors use a step-by-step approach to show how economists have used these methods and how they approach the problem of assessing economic damage. The book begins by describing the importance of economic valuation of marine damages, the history of concern over marine pollution, and the development of economic methodologies to assess damage from it. Following that, the book: considers types of marine pollution and their effects on organisms, ecosystems, and humans, and the corresponding economic effects of those biological impacts introduces the economic principles and methods needed to understand and to assess economic damages expresses losses from water quality impairments in terms of economic value introduces the basic economic techniques that have been developed and used to measure changes in economic value discusses how to apply those economic techniques, and presents a variety of practical examples explores limitations and problems that can arise in such applied work. Economic Losses from Marine Pollution includes all of the relevant economic theory together with specific examples of how that theory has been and can be applied. It offers environmental professionals with little or no background in economics the basic economic tools needed to understand economic valuations of environmental damage. --Publisher.
Mostrar más [+] Menos [-]Application of Different Extraction Methods for the Quality Control of Water
2001
Buszewski, Boguslaw | Ligor, Tomasz
The determination of chlorocarbons in drinking wateris described. The chlorocarbons studied include:tetrachloromethane, 1,1,1-trichloroethane, tribromomethane,bromodichloromethane, dibromochloromethane. Three methods ofsample preparation were compared: liquid-liquid extraction(LLE), purge & trap (P&T) and direct aqueous injection (DAI).The samples of drinking water were taken from Toruń (Poland):local sources, municipal water intake, drilled wells. Theobtained data allowed to create the map of chlorocarbonscontamination for Toruń town. Repeatability, linearity anddetection limits of LLE, P&T, DAI were evaluated forhalocarbons under investigation.
Mostrar más [+] Menos [-]Effects of H2SO4 and HNO3 on Soil Acidification and Aluminum Speciation in Variable and Constant Charge Soils
2001
Xu, R. K. | Ji, G. L.
The difference in effect on acidification and species of aluminum speciation between HNO₃ and H₂SO₄for two contrasting types of soils in surface charge was investigated. The results show that the effect of H₂SO₄ on acidification of variable charge soils (Ferric Acrisol and Haplic Acrisol) of subtropical regions wasweaker than that of HNO₃, due to the specific adsorption of SO₄ ²⁻ and the accompanied release of OH⁻. For two constant charge soils, Haplic Luvisol andEutric Cambisol, the difference in effect between the two acids is small. The concentrations of total inorganic monomeric aluminum, Al³⁺, Al-F complexes and Al-SO₄complexes in the extract from variable charge soils are alsolower in H₂SO₄ systems than those in HNO₃ systems, whereas the reverse is true for constant charge soils, except the concentration of Al³⁺. For variable charge soils, Al-F complexes are the major species of inorganic monomeric aluminum at high pH butAl³⁺ might contribute to a largepart at low pH, while for constant charge soils Al-F complexes contribute almost exclusively to the inorganic monomeric aluminum. The presence of a large amount of SO₄ ²⁻ in the extract from the constant charge soilsleads to a higher proportion of Al-SO₄ complexes in totalinorganic monomeric aluminum than that from variable charge soil, although the numerical value of proportion is small.
Mostrar más [+] Menos [-]Antimony as a Tracer of the Anthropogenic Influence on Soils and Estuarine Sediments
2001
Cal-Prieto, M. J. | Carlosena, A. | Andrade, J. M. | Martínez, M. L. | Muniategui, S. | López-Mahía, P. | Prada, D.
The aim of this work was to evaluate antimony (Sb) as apotentially valuable tracer of the anthropogenic impact on soilsand estuarine sediments. Antimony was determined in fifteenroadsoils from a medium-size city, La Coruña (NW of Spain);and twelve sediments from two estuaries (La Coruña and Ares-Betanzos). Sb determination was accomplished in a rapid andreliable way by directly measuring the solid samples with anautomatic ultrasonic slurry sampling-ETAAS device. Soil contentsranged from 0.29 to 8.81 μg g⁻¹. A relation between Sbconcentration and motor vehicle intensity was observed.Regarding estuarine sediments, Sb amounted from 0.22 to 1.51 μg g⁻¹, for the La Coruña estuary and 0.24 to 0.71 μg g⁻¹, forthe Ares-Betanzos estuary; higher Sb values were found forcoastal locations whereas lower contents corresponded to `inner'samples. In order to confirm these findings, other pollutantswere studied: As, Cd, Co, Cr, Cu, Ni, Pb, Zn, aliphatichydrocarbons (AH) and polycyclic aromatic hydrocarbons (PAH).These values, along with the Sb ones, were subjected tomultivariate studies intended to elucidate whether Sb correlated(and to what extent) to other well-known anthropogenic pollutants. Thus, Sb became associated to Cd, Cu, Pb and Zn in road soils and to As, Cu, Zn, PAH, Pb and unresolved hydrocarbons, in sediments.
Mostrar más [+] Menos [-]Nitrous Oxide Emission from Soil with Different Fertilizers, Water Levels and Nitrification Inhibitors
2001
Pathak, Himanshu | Nedwell, D. B.
The effects of urea, (NH₄)₂SO₄, KNO₃, and NH₄NO₃ on nitrous oxide (N₂O) emission from soil at field capacity and submerged condition were studied during 120 days in the laboratory. Soils in both moisture regimes gave higher emissions in the beginning, which were reduced later. Total emission of N₂O was higher at submergence as compared to field capacity regardless of fertilizer type. At field capacity soil fertilized with ureaemitted the highest amount of N₂O (1903 μg N₂O-N kg⁻¹ soil) during 120 days while at submerged condition, soil with NH₄NO₃ gave the highest emission (4843 μg N₂O-N kg⁻¹ soil). In another study, the efficacy of seven nitrification inhibitors in reducing the emission of N₂O-N from soil fertilized with urea was tested in the laboratory. Nitrapyrin, 2-amino-4-chloro-6-methylpyrimidine (AM), and dicyandiamide (DCD) reduced the emission to 12, 24, and 63% that of urea, respectively, whereas sodium thiosulphate, sulphur, acetylene,and thiourea had no effect on emission of N₂O. In submerged conditions none of the inhibitors reduced the emission.
Mostrar más [+] Menos [-]Distribution of Trace Elements in Tissues of Two Shrimp Species from Persian Gulf and Effects of Storage Temperature on Elements Transportation
2001
Pourang, N. | Amini, G.
This study is focussed on evaluation of temperature effectduring frozen storage on movement of trace elements in differenttissues (exoskeleton, carapace and abdominal muscle) of twocommercially important shrimp species (Penaeusmerguiensis and Metapenaues affinis). Moreoverrelationships between total length and sex of specimens with concentration of trace elements in selected tissues were assessed. Concentrations of Cd, Cr, Cu, Fe, Mn, Ni and Znin samples were determined by ICP-AES. Only in the case of Niand Zn sex related differences could be observed. With theexception of Cu, the trace metals distributed significantlydifferent between the tissues. The only significant differencesbetween species were found in bioaccumulation of Mn. Sizedependent relationship was observed only for Ni. Associationsbetween Mn and Fe were positively and highly significant in allthe cases. The levels of all the metals in muscle of the shrimpsfrom the studied region were comparable to other world areas. MeanCu and Zn levels in edible parts of M. affinis stored at–10 °C exceeded some existing guidelines, while the concentrations at –30 °C were somewhat lower than them.
Mostrar más [+] Menos [-]Environmental Impacts of Landfill Bioreactorcells in Comparison to Former Landfill Techniques
2001
Binder, Michael | Bramryd, Torleif
Former and present landfill techniques at the Filbornaplant in Helsingborg, South Sweden are compared withrespect to impacts on the environment. This includes thepotential for nutrient recovery and heavy metalimmobilisation in the waste residue. The results showthat optimised landfill bioreactor-cells have a higherturn-over rate for organic matter compared to the formerlandfills, whereas the retention capacity for heavymetals in both systems was surprisingly high. Full scaleleachate data, as well as a laboratory leachingexperiments confirmed the role of bioreactor cells asanaerobic filters enabling a separation of nutrients froma mixed waste, while the toxic metals are retained. Theconclusion of this article is that by simple measures, thebiological processes can be optimised, resulting inhigher turn-over rates for organic matter and thusaccelerated waste stabilisation.
Mostrar más [+] Menos [-]Association of the Fungicide Propiconazole with Size Fractionated Material from a Silty Clay Soil – S.E. Norway
2001
Riise, G. | Madsen, H. | Krogstad, T. | Nandrup Pettersen, M.
Eroded soil material may be an important transporting agent for pesticides that are strongly sorbed to soil. The abilityof the fungicide propiconazole to interact with colloidal andparticulate materials has been studied by means of sorptionand desorption experiments. Size separation of silty clay soilfrom Mørdre, Norway and subsequent characterization showedthat different size fractions of soil possessed different physical and chemical properties and, therefore, different capacity to associate with propiconazole. A large part of the soil organic carbon was associated with coarser material (2–0.02 mm), which also showed higher affinity towards propiconazole than for smaller size fractions (<20 and <2 μm). Similar K ₒc values (2306 and 2244) for the size fractions <2 and <20 μm indicate that organic carbon played a dominant role in the sorption of propiconazole. Furthermore, organic carbon associated with these size fractions seemed to have similar properties withrespect to binding of propiconazole. Although, poor in organiccarbon (0.4%), the smallest size fraction (<2 μm) had higher sorption capacity for propiconazole compared to the medium size fraction (<20 μm). Higher sorption for the smallest size fraction (<2 μm) is probably due to higherspecific surface area, cation exchange capacity and content of Fe/Al oxides (free, organically bound and amorphous oxides) than the other size fractions. Results from the desorption experiments indicate that a part of propiconazole associates with sites in the soil material that resist desorption. Fluvialsediments originating from propiconazole treated fields may, therefore, represent potential reservoirs of propiconazole.Treatment with H₂O₂ modified the sorption/desorptioncharacteristics of the soil beyond that which could be expectedsimply by the removal of organic material. The pH values for all the size fractions decreased, and the specific surface areaof the medium sized fraction (<20 μm) increased from 14 to 19 m² g⁻¹ after the treatment with H₂O₂,probably due to disruption of the aggregate structure. Carrying out fractionation and separation procedures, it is important to be aware of physical and chemical changes that areintroduced during the different steps. An effort should be made to develop fractionation methods that keep the original characteristics of the soil material as intact as possible.
Mostrar más [+] Menos [-]Common hydrophytes as bioindicators of nickel, chromium and cadmium pollution
2001
Zurayk, R. | Sukkariyah, B. | Baʻlabakkī, Ramzī
Twelve Mediterranean hydrophyte species collected inLebanon were evaluated for their potential asbioindicator species for heavy metal pollution innutrient cultures enriched with 1 ppm Cr, Ni and Cd.These were: Nasturtium officinale R.Br, Apium nodiflorum L., Veronica beccabunga L., Veronica anagallis aquatica L., Veronicalysimachioides L., Veronica anagalloides L., Mentha longifolia L., Mentha aquatica L., Mentha pulegium L., Potentilla reptansL., Mentha sylvestris L., and Cardamine uliginosa L.. Large variability in responseto exposure to the heavy metals was observed. Growthrates remained high during the experimental period,indicating that the plants were little affected by thepresence of the metal at the experimentalconcentration. Metal accumulation and bioconcentrationvaried within at least one order of magnitude, andranged from less than 10 to over 200. Cr waspreferentially accumulated in the roots. All speciesbut M. pulegium, P. reptans and V. anagallisaquatica accumulated and bioconcentrated sufficientCr to qualify as bioindicator species. Five of thespecies that accumulated Cr also accumulated Ni, withthe same partitioning into the root. These were: N. officinale, C. uliginosa sp., M. longifolia, M. aquatica and M. sylvestris, all of which mayalso be used as bioindicators of Ni pollution. Onlyone species, M. aquatica, accumulated Cdsignificantly, and may, therefore, be used as abioindicator for all three metals.
Mostrar más [+] Menos [-]The Effects of Urbanization on the Chemical Quality of Three Tidal Bayous in the Gulf of Mexico
2001
Lewis, Michael A. | Moore, James C. | Goodman, Larry R. | Patrick, James M. | Stanley, Roman S. | Roush, Thomas H. | Quarles, Robert L.
Water and sediment quality in threetidal bayous located near Pensacola, Florida, wereassessed during 1993–1995. The primary objective wasto determine the environmental condition of therelatively small urban bayous by comparing thechemical quality of the sediments and surface waterwith published guidelines and criteria developed toprotect marine life. Surface water concentrations ofmost potential toxicants such as heavy metals,organochloride pesticides, PAHs and PCBs were usuallybelow method detection limits. The major exception tothis trend was for copper which consistently exceededFlorida and National acute and chronic water qualitycriteria. Nickel, cadmium and chromium intermittentlyexceeded these criteria. Sediment contamination wassite-specific and chemically diverse. Theconcentrations of as many as 17 compounds exceededproposed Florida sediment quality assessmentguidelines indicating the potential for adversebiological effects. Nutrient concentrations, with oneexception, were below average levels found in otherFlorida estuaries. Seasonal variation in contaminantconcentrations for sediment collected from the samesampling station was less than an order of magnitude. The differences in the concentrations of the sameanalytes as measured for the multiple samplingstations located within the same bayou varied 1 to 2orders of magnitude and over 2 orders of magnitude forthe 20 sampling stations located in the three bayous. A within-bayou sediment contaminant gradient wasevident; sediment quality generally improved seaward.
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