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141.
The food and feeding ecology of the poorly known southern long-finned pilot whale (Globicephala melas edwardii) was investigated using ecological tracers (muscle and skin δ13C and δ15N, and total mercury, Hg) on individuals from two mass strandings together with at-sea observations of live animals in Kerguelen waters, southern Indian Ocean. Sightings of cetaceans from longliners over 9 years (2003–2012) emphasized the regular occurrence of pilot whales in slope waters surrounding the archipelago. Tissue δ13C values (a proxy of consumer foraging habitat) suggest that pilot whales fed in slope waters and in oceanic subantarctic waters over the last months preceding stranding. Tissue δ15N values and Hg concentration (dietary proxies) indicate a high trophic position (~4.7) for the pilot whales, likely corresponding to a mixed diet of fish and squid (not crustaceans) of undetermined species. Both skin and muscle Hg concentrations were positively and linearly correlated to individual size with no concomitant δ15N changes, which can be interpreted as a progressive Hg accumulation in tissues of individuals throughout life with no parallel dietary shift. Skin and muscle Hg concentrations were linearly and positively related; hence, Hg skin could be used as a proxy of Hg concentration in muscle (a main Hg reservoir of the body). Kerguelen southern long-finned pilot whales were less Hg contaminated than most pilot whale populations studied so far, thus suggesting that they are not at a high risk to Hg-induced damages in the remote islands of the Southern Ocean.  相似文献   
142.
Concerns over water scarcity, climate change, and environmental health risks have prompted some Asian cities to invest in river rehabilitation, but deciding on the end goals of rehabilitation is a complex undertaking. We propose a multidisciplinary framework linking riparian landscape change to human well‐being, providing information relevant to decision makers, in a format that facilitates stakeholder involvement. We illustrate this through a case study of the densely settled, environmentally degraded, and flood prone Ciliwung River flowing through metropolitan Jakarta, Indonesia. Our methodology attempts to respond to this complexity through an iterative approach, strongly based on conceptualization and mathematical modeling. Nested hydrologic, hydrodynamic, and water quality models provide outputs at catchment‐, corridor‐, and localized site‐scales. Advanced 3‐D landscape modeling is used for procedural design and precise visualization of proposed changes and their impacts, as predicted by the mathematical models. Finally, participatory planning and design methods allow us to obtain critical stakeholder feedback in shaping a socially acceptable approach. Our framework aims at demonstrating that a change in paradigm in river rehabilitation is possible, and providing future scenarios that balance concerns over flooding, water quality, and ecology, with the realities of a rapidly growing megacity.  相似文献   
143.
The classification of waste as hazardous could soon be assessed in Europe using largely the hazard properties of its constituents, according to the the Classification, Labelling and Packaging (CLP) regulation. Comprehensive knowledge of the component constituents of a given waste will therefore be necessary. An analytical protocol for determining waste composition is proposed, which includes using inductively coupled plasma (ICP) screening methods to identify major elements and gas chromatography/mass spectrometry (GC–MS) screening techniques to measure organic compounds. The method includes a gross or indicator measure of ‘pools’ of higher molecular weight organic substances that are taken to be less bioactive and less hazardous, and of unresolved ‘mass’ during the chromatography of volatile and semi-volatile compounds. The concentration of some elements and specific compounds that are linked to specific hazard properties and are subject to specific regulation (examples include: heavy metals, chromium(VI), cyanides, organo-halogens, and PCBs) are determined by classical quantitative analysis. To check the consistency of the analysis, the sum of the concentrations (including unresolved ‘pools’) should give a mass balance between 90% and 110%. Thirty-two laboratory samples comprising different industrial wastes (liquids and solids) were tested by two routine service laboratories, to give circa 7000 parameter results. Despite discrepancies in some parameters, a satisfactory sum of estimated or measured concentrations (analytical balance) of 90% was reached for 20 samples (63% of the overall total) during this first test exercise, with identified reasons for most of the unsatisfactory results. Regular use of this protocol (which is now included in the French legislation) has enabled service laboratories to reach a 90% mass balance for nearly all the solid samples tested, and most of liquid samples (difficulties were caused in some samples from polymers in solution and vegetable oil). The protocol is submitted to French and European normalization bodies (AFNOR and CEN) and further improvements are awaited.  相似文献   
144.
This paper provides an introduction to the special issue of the Journal of Cleaner Production on “The Sustainability of Seafood Production and Consumption”. The purpose of the special issue is to bring together a series of papers that will form a nucleus for the growth of an emerging area of scholarship. Overfishing and marine habitat damage have generated a global crisis in the production of seafood. In order to respond to this crisis we need systems for the management of seafood production and consumption that will comprehensively reduce and eventually eliminate wastefulness in both capture fisheries and aquaculture systems. Thirteen papers address these issues, with focuses on: seafood harvesting practices, fish processing, life cycle assessment, eco-efficiency, management of wastes, seafood distribution and consumption, total energy costs, eco-labeling, and the conservation of resources and biodiversity. We conclude that major changes are required in our approaches to the management of both the marine environment and our seafood capture and production systems. We also conclude that steps have been taken in this direction, but there is still far to go.  相似文献   
145.
In the context of ecosystem approach to fisheries, it is a critical issue to build management tools able to predict the possible trajectories of ecosystems under various human pressure or environmental variations, but also capable to point out influent and sensitive components.  相似文献   
146.
Haloacetic acids are atmospheric oxidation products of airborne C2-halocarbons which are important solvents and propellants. Levels of trichloroacetate (TCA) in conifer needles from mountain ranges in Germany (Black Forest, Erzgebirge) and from two sites in Finland are compared; TCA is present in conifer needles at concentrations up to 0.7 μmol/kg, MCA up to 0.2 μmol/kg. At the Finnish sites, TCA-concentrations and branch degeneration symptoms of Scots pine are correlated. Monochloroacetate (MCA) has been determined in needle samples from Southern Germany in concentrations exceeding its phytotoxicity threshold towards photoautotrophic organisms. Data on atmospheric chloroacetate levels in Germany are also given; ambient air levels of chloroacetic acids range from about 2 pmol/m3 (TCA) to 390 pmol/m3 (MCA). TCA and dichloroacetic acid (DCA) arise from atmospheric oxidation of airborne C2-chlorocarbons, while the source of MCA is not yet known; several tentative pathways are suggested.  相似文献   
147.
The present study was carried out to investigate the potential ameliorative effects of lycopene against chlorpyrifos (CPF) toxicity in carp. The fish were divided into 7 different experimental groups and received the following treatments: Group 1, control; Group 2, orally administered corn oil; Group 3, oral lycopene (10 mg kg?1 body weight); Group 4, exposure to 0.040 mg L?1 CPF; Group 5, exposure to 0.040 mg L?1 CPF plus oral administration of 10 mg kg?1 lycopene; Group 6, exposure to 0.080 mg L?1 CPF; and Group 7, exposure to 0.040 mg L?1 CPF plus oral administration of 10 mg kg?1 lycopene. Treatment was continued for 14 d and samples of the blood and tissue (liver, kidney, and gill) were collected at the end of the experiment and analysed for their oxidant–antioxidant status, including the malondialdehyde (MDA) levels, and the superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity. The samples were also measured for changes in the haematological parameters, such as the red blood cell (RBC) and white blood cell (WBC) counts, the haemoglobin concentration (Hb), the haematocrit (Ht) level, and the erythrocyte indices: the mean corpuscular volume (MCV), the mean corpuscular haemoglobin (MCH) and the mean corpuscular haemoglobin concentration (MCHC). The findings of this study demonstrated that CPF had a negative effect on the haematological parameters and the antioxidant enzyme activities of the fish; this toxic effect was neutralised by the administration of lycopene. The present results suggest that lycopene (10 mg kg?1) can be effective in the protection of CPF-induced toxicity in fish.  相似文献   
148.
Nitrogen contamination of ground and surface water in the Seine, Somme and Scheldt watersheds, as well as in the receiving coastal marine zones, results in severe ecological problems. Previous modelling results showed that the implementation of classical management measures involving improvement of wastewater purification and “good agricultural practices” are not sufficient to obviate these problems. A more radical scenario was therefore established, consisting of a generalised shift to organic agriculture of all agricultural areas in the three basins, with the additional constraints that livestock is fed only on local fodder production. This scenario involves an increased livestock density in the Seine and Somme and a decrease in livestock in the Scheldt basin. It leads to a significant reduction of agricultural production that finally brings the three basins closer to autotrophy/heterotrophy equilibrium. Nitrate concentrations in most of the drainage network would drop below the threshold of 2.25 mgN/l in the most optimistic hypothesis. The excess of nitrogen over silica (with respect to the requirements of marine diatoms) delivered into the coastal zones would be decreased by a factor from 2 to 5, thus strongly reducing, but not entirely eliminating the potential for marine eutrophication.  相似文献   
149.
Treatments to reduce solids content in liquid manure have been developed, but little information is available on gaseous N emissions and plant N uptake after application of treated liquid swine manure (LSM). We measured crop yield, N uptake, and NH3 and N2O losses after the application of mineral fertilizer (NH4 NO3), raw LSM, and LSM that was decanted, filtered, anaerobically digested, or chemically flocculated. The experiment was conducted from 2001 to 2003 on a loam and a sandy loam cropped to timothy (Phleum pratense L.) with annual applications equivalent to 80 kg N ha(-1) in spring and 60 kg N ha(-1) after the first harvest. Raw LSM resulted in NH3 emissions three to six times larger (P < 0.05) than mineral fertilizer. The LSM treatments reduced NH3 emissions by an average of 25% compared with raw LSM (P < 0.05). The N2O emissions tended to be higher with raw LSM than with mineral fertilizer. The LSM treatments had little effect on N2O emissions, except for anaerobic digestion, which reduced emissions by >50% compared with raw LSM (P < 0.05). Forage yield with raw LSM was >90% of that with mineral fertilizer. The LSM treatments tended to increase forage yield and N uptake relative to raw LSM. We conclude that treated or untreated LSM offers an alternative to mineral fertilizers for forage grass production but care must be taken to minimize NH3 volatilization. Removing solids from LSM by mechanical, chemical, and biological means reduced NH3 losses from LSM applied to perennial grass.  相似文献   
150.
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