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Management of marine cage aquaculture : Environmental carrying capacity method based on dry feed conversion rate
2007
Huiwen, Cai | Yinglan, Sun
GOAL, SCOPE AND BACKGROUND: Marine cage aquaculture produces a large amount of waste that is released directly into the environment. To effectively manage the mariculture environment, it is important to determine the carrying capacity of an aquaculture area. In many Asian countries trash fish is dominantly used in marine cage aquaculture, which contains more water than pellet feed. The traditional nutrient loading analysis is for pellet feed not for trash fish feed. So, a more critical analysis is necessary in trash fish feed culturing areas. METHODS: Corresponding to FCR (feed conversion rate), dry feed conversion rate (DFCR) was used to analyze the nutrient loadings from marine cage aquaculture where trash fish is used. Based on the hydrodynamic model and the mass transport model in Xiangshan Harbor, the relationship between the water quality and the waste discharged from cage aquaculture has been determined. The environmental carrying capacity of the aquaculture sea area was calculated by applying the models noted above. RESULTS: Nitrogen and phosphorus are the water quality parameters considered in this study. The simulated results show that the maximum nitrogen and phosphorus concentrations were 0.216 mg/L and 0.039 mg/L, respectively. In most of the sea area, the nutrient concentrations were higher than the water quality standard. The calculated environmental carrying capacity of nitrogen and phosphorus in Xiangshan Harbor were 1,107.37 t/yr and 134.35 t/yr, respectively. The waste generated from cage culturing in 2000 has already exceeded the environmental carrying capacity. DISCUSSION: Unconsumed feed has been identified as the most important origin of all pollutants in cage culturing systems. It suggests the importance of increasing the feed utilization and improving the feed composition on the basis of nutrient requirement. For the sustainable development of the aquaculture industry, it is an effective management measure to keep the stocking density and pollution loadings below the environmental carrying capacity. CONCLUSIONS: The DFCR-based nutrient loadings analysis indicates, in trash fish feed culturing areas, that it is more critical and has been proved to be a valuable loading calculation method. The modeling approach for Xiangshan Harbor presented in this paper is a cost-effective method for assessing the environmental impact and determining the capacity. Carrying capacity information can give scientific suggestions for the sustainable management of aquaculture environments. RECOMMENDATIONS AND PERSPECTIVES: It has been proved that numerical models were convenient tools to predict the environmental carrying capacity. The development of models coupled with dynamic and aquaculture ecology is a requirement of further research. Such models can also be useful in monitoring the ecological impacts caused by mariculture activities.
显示更多 [+] 显示较少 [-]Using phytoremediation technologies to upgrade waste water treatment in Europe
2007
Schröder, Peter | Navarro-Aviñó, Juan | Azaizeh, Hassan | Goldhirsh, Avi Golan | DiGregorio, Simona | Komives, Tamas | Langergraber, G. (Günter) | Lenz, Anton | Maestri, Elena | Memon, Abdul R. | Ranalli, Alfonso | Sebastiani, L. | Smrcek, Stanislav | Vanek, Tomas | Vuilleumier, Stephane | Wissing, Frieder
GOAL, SCOPE AND BACKGROUND: One of the burning problems of our industrial society is the high consumption of water and the high demand for clean drinking water. Numerous approaches have been taken to reduce water consumption, but in the long run it seems only possible to recycle waste water into high quality water. It seems timely to discuss alternative water remediation technologies that are fit for industrial as well as less developed countries to ensure a high quality of drinking water throughout Europe. MAIN FEATURES: The present paper discusses a range of phytoremediation technologies to be applied in a modular approach to integrate and improve the performance of existing wastewater treatment, especially towards the emerging micro pollutants, i.e. organic chemicals and pharmaceuticals. This topic is of global relevance for the EU. RESULTS: Existing technologies for waste water treatment do not sufficiently address increasing pollution situation, especially with the growing use of organic pollutants in the private household and health sector. Although some crude chemical approaches exist, such as advanced oxidation steps, most waste water treatment plants will not be able to adopt them. The same is true for membrane technologies. DISCUSSION: Incredible progress has been made during recent years, thus providing us with membranes of longevity and stability and, at the same time, high filtration capacity. However, these systems are expensive and delicate in operation, so that the majority of communities will not be able to afford them. Combinations of different phytoremediation technologies seem to be most promising to solve this burning problem. CONCLUSIONS: To quantify the occurrence and the distribution of micropollutants, to evaluate their effects, and to prevent them from passing through wastewater collection and treatment systems into rivers, lakes and ground water bodies represents an urgent task for applied environmental sciences in the coming years. RECOMMENDATIONS: Public acceptance of green technologies is generally higher than that of industrial processes. The EU should stimulate research to upgrade existing waste water treatment by implementing phytoremediation modules and demonstrating their reliability to the public.
显示更多 [+] 显示较少 [-]How standards drive taxes: the political economy of tailpipe pollution
2007
Gulati, Sumeet | Roy, Devesh
To control tailpipe pollution, governments often use environmental product standards and consumption taxes in conjunction (for example, the use of fuel economy standards and gasoline taxes to restrict automobile pollution in the US). Further, the choice of standards and consumption taxes is often independently influenced by special interests. For example, domestic producers have the incentive to influence environmental product standards, and likewise, domestic consumers have the incentive to influence the choice of the consumption tax. In this paper we explore the political link between environmental standards and consumption taxes in the presence of independent special interests. We find that despite the independence of special interests, the political outcome is inextricably linked. This political link is different from the welfare maximizing second-best link usually expected between two related policies, and is crucial in correctly anticipating policy outcomes. Specifically, we find that the government's choice of an environmental standard influences political incentives in the choice of the consumption tax. As the environmental standard falls, a higher demand for the environmentally damaging product develops. This higher demand increases the incentives for consumers to lobby for lower consumption tax. Under certain conditions, this political link is large enough to result in a complementary relationship between the two policies in equilibrium. The complementary relationship implies that a lower standard results in a lower consumption tax and vice versa when the standard is higher.
显示更多 [+] 显示较少 [-]Small reservoir non-point source pollution identification and water quality monitoring for domestic livestock and irrigation use in Mzingwane Catchment (Zimbabwe)
2007
Masona, C.
Chernobyl -- what have we learned?
2007
Onishi, Yasuo | Voĭt︠s︡ekhovich, O. V. (Oleg V) | Zheleznyak, Mark J.
France
2007
Probst, Anne | Leguédois, Sophie | Laboratoire Ecologie Fonctionnelle et Environnement (LEFE) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)
Working group on effects of the convention on long-rangr transboundary air pollution
显示更多 [+] 显示较少 [-]Groundwater pollution and emerging environmental challenges of industrial effluent irrigation in Mettupalayam Taluk, Tamil Nadu
2007
Mukherjee, S. | Nelliyat, P.
Industrial disposal of effluents on land and the subsequent pollution of groundwater and soil of surrounding farmlands ? is a relatively new area of research. The environmental and socioeconomic aspects of industrial effluent irrigation have not been studied as extensively as domestic sewage based irrigation practices, at least for a developing country like India. The disposal of effluents on land has become a regular practice for some industries. Industries located in Mettupalayam Taluk, Tamil Nadu, dispose their effluents on land, and the farmers of the adjacent farmlands have complained that their shallow open wells get polluted and also the salt content of the soil has started building up slowly. This study attempts to capture the environmental and socioeconomic impacts of industrial effluent irrigation in different industrial locations at Mettupalayam Taluk, Tamil Nadu, through primary surveys and secondary information. This study found that the continuous disposal of industrial effluents on land, which has limited capacity to assimilate the pollution load, has led to groundwater pollution. The quality of groundwater in shallow open wells surrounding the industrial locations has deteriorated, and the application of polluted groundwater for irrigation has resulted in increased salt content of soils. In some locations drinking water wells (deep bore wells) also have a high concentration of salts. Since the farmers had already shifted their cropping pattern to salt-tolerant crops (like jasmine, curry leaf, tobacco, etc.) and substituted their irrigation source from shallow open wells to deep bore wells and/or river water, the impact of pollution on livelihoods was minimized. Since the local administration is supplying drinking water to households, the impact in the domestic sector has been minimized. It has also been noticed that in some locations industries are supplying drinking water to the affected households. However, if the pollution continues unabated it could pose serious problems in the future.
显示更多 [+] 显示较少 [-]Report on water quality survey and pollution in Kurunegala, Sri Lanka
2007
Dissanayake, Priyanka | Clemett, Alexandra | Jayakody, Priyantha | Amerasinghe, Priyanie H.
This project is funded by the European Commission under its Asia Pro Eco II Program. It is undertaken by the International Water Management Institute (IWMI), Sri Lanka; COSI, Sri Lanka; the International Water and Sanitation Centre (IRC), the Netherlands; NGO Forum for Drinking Water Supply and Sanitation, Bangladesh; and the Stockholm Environment Institute (SEI), Sweden. The project pilot cities are Rajshahi City in Bangladesh and Kurunegala City in Sri Lanka.
显示更多 [+] 显示较少 [-]Challenges in quantifying biosphere - atmosphere exchange of nitrogen species
2007
Sutton, Mark A. | Nemitz, Eiko | Erisman, Jan Willem | Beier, Claus | Butterbach-Bahl, Klaus | Cellier, Pierre | de Vries, Wim | Cotrufo, R. | Skiba, Ute | Di Marco, Chiara | Jones, Stephanie K | Laville, Patricia | Soussana, Jean-Francois | Loubet, Benjamin | Twigg, Marsailidh | Famulari, Daniela | Whitehead, J. | Gallagher, Martin W. | Neftel, Albrecht | Dämmgen, Ulrich
PAH metabolites in bile fluids of dab (Limanda limanda) and flounder (Platichthys flesus): spatial distribution and seasonal changes
2007
Kammann, Ulrike