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Nguyen Thi Van Ha A. Prem Ananth C. Visvanathan V. Anbumozhi 《Journal of Cleaner Production》2009,17(14):1272-1280
Eco-industrial networking is considered as a new approach for businesses to improve their competitiveness, economic viability and human and ecosystem health. A cyclic material flow with alternative usage of all materials in the loop is an essential feature of an eco-industrial network. While eco-industrial networking has been primarily applied on the high-tech sector, this paper attempts to apply the principles on the fishery sector of An Giang, a Vietnamese province in the Mekong River Delta. An Giang Province has its own market share in the trade of Tra and Basa fish. The industries in the value chain of Tra and Basa are in a situation that forces them to improve their competitiveness to retain the market share. It was found that forming an eco-industrial network and recruiting new businesses to utilize all materials in the process provides additional revenue apart from reducing waste disposal concerns. This paper details the current market situation, the issues faced and material flow patterns and presents a feasible eco-industrial network. The results of the study indicate that the eco-industrial network creates positive impacts in terms of increased competitiveness, improved socio-economic conditions and cleaner environment. 相似文献
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Network-bound systems such as water and energy systems are increasingly confronted with environmental problems that cannot be solved without changing their modes of provision. More than any other flow provided through a network-bound system, the waste water flow comes very close to intimate personal and social life, complicating the introduction of environmental innovations in this sector. Using the concepts of trust and identity, questions concerning changing consumer roles in two cases of Decentralised Sanitation and Reuse Systems in the Netherlands are addressed. In both cases the building of trust within provider networks and between consumers and providers, as well as the possibility for consumers and providers to identify themselves with the aims of the project were key factors determining the success or failure of environmental innovations in waste water flows. 相似文献
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Impact of groundwater markets in India on water use efficiency: a data envelopment analysis approach
Manjunatha AV Speelman S Chandrakanth MG Van Huylenbroeck G 《Journal of environmental management》2011,92(11):2924-2929
In the hard rock areas of India, overdraft of groundwater has led to negative externalities. It increased costs of groundwater irrigation and caused welfare losses. At the same time informal groundwater markets are slowly emerging and are believed to improve water distribution and to increase water use efficiency in the irrigation sector. These claims are evaluated in this study. For this purpose data was collected from a sample containing three different groups of water users: water sellers, water buyers and a control group of non-traders. First the socio-economic characteristics of these groups are compared. Then the efficiency of water use of the three groups is studied using Data Envelopment Analysis. The results indicate that groundwater markets provide resource poor farmers access to irrigation water, giving them the opportunity to raise their productivity. Water buyers are furthermore shown to be most efficient in their water use, while water sellers are also shown to be more efficient than the control group. The differences in efficiency between the groups are statistically significant. The demonstrated potential of groundwater markets to improve the efficiency of water use and to increase equity in resource access should be taken into account by the Indian government when deciding on their attitude towards the emerging groundwater markets. 相似文献
629.
Irrigation pricing policies and its impact on agricultural inputs demand in Tunisia: a DEA-based methodology 总被引:1,自引:0,他引:1
Frija A Wossink A Buysse J Speelman S Van Huylenbroeck G 《Journal of environmental management》2011,92(9):2109-2118
This paper estimates farmers' individual irrigation water demand functions employing the information hidden in individual farmers' technical efficiency. This information is extracted through the development of a new deductive methodology based on inverse Data Envelopment Analysis (DEA) models. The empirical results for Tunisia show that farmers who are more technically efficient have less elastic irrigation water demand functions; these farmers would adjust demand only to a limited extent and they can afford the water price. In contrast, water pricing significantly affects those that are less efficient. These farmers shift towards a different cropping pattern using significantly less water and more land when the price of water increases. Thus, higher water prices would threaten this category's livelihood if their efficiency is not improved. However, if the technical efficiency of these farmers were to improve, then it would be more difficult to reach water saving objectives since their demand will also become highly inelastic. The findings have important implications in view of the objectives of Tunisia water policy which include:full cost recovery, continuity of the irrigation activity, and water saving at the national level. 相似文献
630.
Kathryn L. Van Alstyne Katie J. Anderson Amanda K. Winans Sue-Ann Gifford 《Marine Biology》2011,158(9):2087-2094
Ulvaria obscura, a prominent component of green tide blooms in Washington, is unique among macroalgae because it contains dopamine. To examine
dopamine release by U. obscura following simulated low tides, we conducted 6 field experiments in which algae were emersed for 75 min and then immersed
in filtered seawater (FSW). Dopamine was measured in algal tissues prior to emersion and 3 h after immersion and in seawater
for 3 h following immersion. In our experiments, algae released 7–100% of their tissue dopamine, resulting in average seawater
concentrations of 3–563 μM. In 5 of 6 experiments, seawater dopamine concentrations were highest immediately after immersion,
and then decreased over time. The percentages of dopamine released were not correlated with tissue dopamine concentrations,
but were positively correlated with solar radiation during emersion. The release of dopamine, which is both cytotoxic and
genotoxic, may explain the negative effects of U. obscura exudates on marine organisms. 相似文献