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701.
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
702.
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
703.
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
704.
Anh BT Kim DD Tua TV Kien NT Anh do T 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(2):257-262
This study was focused on determining Arsenic (As), Lead (Pb), Cadmium (Cd) and Zinc (Zn) in 33 indigenous plants and 12 soil in-situ plant samples in Thai Nguyen Province, Vietnam. The results showed that the soils of surveyed mining areas contained 181.2- 6754.3 mg kg(-1) As, 235.5-4337.2 mg kg(-1) Pb, 0.8- 419 mg kg(-1) Cd and 361.8-17565.1 mg kg(-1) Zn depending on the characteristics of each mining site. These values are much higher than those typical for normal soil. The heavy metal uptake into shoots and roots of 33 indigenous plant species was also determined. Two species of the plants investigated, Pteris vittata L. and Pityrogramma calomelanos L. were As hyperaccumulators, containing more than 0.1% heavy metals in their shoots. Eleusine indica L., Cynodon dactylon L., Cyperus rotundus L. and Equisetum ramosissimum (Vauch) accumulate very high Pb (0.15-0.65%) and Zn (0.22-1.56%) concentration in their roots. Additional experiments to clarify the potential of six these plants as good candidates for phytoremediation of heavy metal pollution soil are being carried out in our laboratory. 相似文献
705.
706.
Le Trinh Hai Pham Hoang Hai Chu Lam Thai Jean Hugé Albert Ahenkan Le Xuan Quynh Vu Van Hieu Nguyen Le The Tung Luc Hens 《Environmental Modeling and Assessment》2011,16(6):541-550
Sustainable development is a widespread concept. Indicator selection and sustainability assessment are basic methods to analyse
the sustainable development process. This study aims to develop a software application to select indicators and to allocate
weightings to the indicators and the sub-indexes, so that they can be listed in a sustainability assessment. The Visual Basic
software is used to develop a software package based on Delphi, analytic hierarchy, normalization and combination processes.
Software for sustainability assessment was developed. Thirty-five indicators are selected as a first step of which eight health
indicators and eight environmental ones and their sub-indexes are given weightings. The indicators are normalized. Sub-indexes
are combined into a composite sustainable development index. The model is validated showing the ‘main features’ of the sustainability
situation on health and environmental aspects in the Quang Tri province during the period 2000–2005. The results support the
decision-making process of the competent authorities. 相似文献
707.
Van Tran Thuan Nguyen Duyen Thi Cam Nguyen Thuong Thi Pham Quynh Trang Vo Dai-Viet N. Nguyen Thanh-Danh Van Pham Thinh Nguyen Trinh Duy 《Environmental science and pollution research international》2021,28(45):63448-63463
Environmental Science and Pollution Research - The emergent occurrence of sulfonamide species involving sulfadiazine (SDZ) and sulfamethazine (SMZ) in aquatic systems can cause a wide range of... 相似文献
708.
Da Le Nhu Hoang Anh Quoc Hoang Thi Thu Ha Nguyen Thi Anh Huong Duong Thi Thuy Pham Thi Mai Huong Nguyen Tien Dat Hoang Van Chung Phung Thi Xuan Binh Le Huu Tuyen Tran Cao Son Dang Thu Hien Vu Ngoc Tu Nguyen Trong Nghia Le Thi Phuong Quynh 《Environmental science and pollution research international》2021,28(9):10622-10632
Environmental Science and Pollution Research - Antibiotic residues and antimicrobial resistance in surface water are issues of global concern, especially in developing countries. In this study, the... 相似文献
709.