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1.
Gunnell Y  Krishnamurthy A 《Ambio》2003,32(4):320-324
Many modern agricultural systems are structured around one dominant form of water storage and distribution, usually large reservoirs. In contrast, in peninsular India, small reservoirs (tanks), predominantly supplied by surface runoff as opposed to river canals have for centuries been the trademark of an entire agrarian civilization, with no equivalent elsewhere in the semiarid tropics. This article focuses on the physical and socioeconomic conditions that underlie the success of an indigenous technology which has for centuries exploited the potential for runoff harvesting by i) optimizing water management for agriculture; and ii) minimizing soil loss. Today, siltation of reservoirs, privatization of water resources, and generalized mining of groundwater, pose a threat to the sustainability of these water-harvesting systems. The ongoing transformation of this common resource pool is critically assessed.  相似文献   

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Jansson U  Kautsky U  Miliander S 《Ambio》2006,35(8):505-512
Production and consumption of food and in a rural area over the last 400 years were reconstructed for a parish in south east Sweden. This was based on a number of different data sources, including historical maps and official demographic and agricultural statistics. Changes in population (and thus consumption) and the production from arable land and livestock were calculated and used to provide an estimate of the area's supply and demand over time, and of the historical sustainability of the area. Overall food productivity was remarkably constant over time, at approximately 0.04 kgC m(-2) y(-1), despite recent changes in population size and the area of cultivated land. The empirical results from the past and the present, together with the future land changes due to shoreline displacement were used to predict the situation in the future. These final estimates can be used in the assessment of risk for exposure to contaminated food for the future population in the area.  相似文献   

4.
Mirza R 《Chemosphere》1999,38(1):207-231
This report reviews the major scientific investigations that have been reported world wide over the last ten years on the effect of plastics on the process and emission performance of energy from waste (EFW) facilities. Concentrations of contaminants in air emissions and other process residues measured during tests with added plastics are compared with concentrations during normal operations and with the stringent emission limits stipulated in municipal waste combustor standards and guidelines in Canada, the United States and the European Union. The emission limits in these standards and guidelines are based on the use of the best technology available (Maximum Achievable Control Technology (MACT) standards in North America and Best Available Technology (BAT) standards in Europe) and are amongst the most stringent in the world.  相似文献   

5.
Environmental Science and Pollution Research - Mutagens present in the environment manifest toxic effects and are considered as serious threat for human health and healthcare. Recent reports reveal...  相似文献   

6.
Environmental Science and Pollution Research - Cancer, a major public health problem, is one of the world’s top leading causes of death. Common treatments for cancer include cytotoxic...  相似文献   

7.
Bange HW  Uher G 《Chemosphere》2005,58(2):177-183
We conducted irradiation experiments with riverine, estuarine, and marine water samples to investigate the possibility of photochemical methane (CH4) formation. CH4 photoproduction was undetectable under oxic conditions or in the absence of methyl radical precursors indicating that its photochemical formation is negligible in the present ocean. Significant photochemical CH4 production was observed in the presence of a methyl radical precursor such as acetone under strictly anoxic conditions. Our results indicate an indirect formation mechanism with coloured dissolved organic matter acting as photosensitizer. We suggest that photochemical CH4 formation might have occurred in the anoxic ocean surface layer of the Archean prior to the onset of O2 accumulation in the atmosphere at around 2300 million years ago. Oceanic CH4 photoproduction via methyl radical (CH3) precursors and its subsequent release to the atmosphere may have contributed to high CH4 mixing ratios in the Archean atmosphere.  相似文献   

8.
Environmental Science and Pollution Research - Energy is the source of economic growth, and energy consumption indicates the country’s state of development. Energy engineering is a relatively...  相似文献   

9.
The suitability of a set of ecophysiological parameters, to be used as early warning indicator to detect signs of a worsening environment around geothermal power plants, was tested by comparison with the diversity of epiphytic lichens, a well-established indicator of geothermal air pollution. Samples of the lichen Evernia prunastri were transplanted around a geothermal power plant at Larderello (Tuscany, Italy) and at a control site, and integrity of cell membranes, concentration of chlorophyll a, b and carotenoids, chlorophyll integrity and variations in pH of thalli were measured. The results showed that cell membrane damage, expressed by changes in electrical conductivity, could be used to detect early (exposure periods as short as 1 month) deleterious effects of geothermal air pollution.  相似文献   

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Environmental Science and Pollution Research - Developing countries have depleted their natural resources in economic interest to achieve high economic growth. Current urbanization patterns and...  相似文献   

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Environmental Science and Pollution Research - Fluoride contamination in groundwater is a major problem throughout the world as well as in India. High-fluoride content was reported in the hot...  相似文献   

13.
Informal recycling of waste (including e-waste) is an emerging source of environmental pollution in India. Polychlorinated biphenyls (PCBs), polychlorinated diphenyl ethers (PBDEs), and heavy metals, among other substances, are a major health concern for workers engaged in waste disposal and processing, and for residents living near these facilities, and are also a detriment to the natural environment. The main objective of this review article was to evaluate the status of these impacts. The review found that, huge quantity of e-waste/waste generated, only a small amount is treated formally; the remainder is processed through the informal sector. We also evaluated the exposure pathways, both direct and indirect, and the human body load markers (e.g., serum, blood, breast milk, urine, and hair), and assessed the evidence for the association between these markers and e-waste exposure. Our results indicated that the open dumping and informal e-waste recycling systems should be replaced by the best available technology and environmental practices, with proper monitoring and regular awareness programs for workers and residents. Further and more detailed investigation in this area is also recommended.  相似文献   

14.
This study demonstrates the utility of using rural ponds as a large-scale rain gauge to detect the importance of atmospheric lead pollution over the last 100 years in industrialized countries. Stable Pb isotopes are used to identify Pb pollution sources and to evaluate the relative importance of anthropogenic sources to the total Pb fluxes found in a semi-rural region of Western Europe (S Belgium). The isotopic ratios of lead in surface layers of a sediment core taken in a pond located at Willerzie and dated by 210Pb geochronology show a pattern that differs clearly from that exhibited in the older sediment layers (pre-1900). These data indicate that the observed increase of lead concentration in the upper sedimentary layers comes from anthropogenic sources which are mainly of atmospheric origin.  相似文献   

15.
Environmental Science and Pollution Research - In the last few decades, wind energy has become a significant source of the renewable energy system, and it is essential to use wind energy for...  相似文献   

16.
Environmental Science and Pollution Research - Parboiling rice mills produce a large amount of wastewater. The effluent from the rice mill contains high concentration of organic and inorganic...  相似文献   

17.
综述了农药生产废水的常用处理方法和资源化技术 ,认为在处理废水的同时 ,应尽可能地回收和利用废水中有用物质 ;同时 ,要合理采用综合处理技术 ,以期达到最佳的处理效果  相似文献   

18.
Emissions from the potential installation of distributed energy resources (DER) in the place of current utility-scale power generators have been introduced into an emissions inventory of the northeastern United States. A methodology for predicting future market penetration of DER that considers economics and emission factors was used to estimate the most likely implementation of DER. The methodology results in spatially and temporally resolved emission profiles of criteria pollutants that are subsequently introduced into a detailed atmospheric chemistry and transport model of the region. The DER technology determined by the methodology includes 62% reciprocating engines, 34% gas turbines, and 4% fuel cells and other emerging technologies. The introduction of DER leads to retirement of 2625 MW of existing power plants for which emissions are removed from the inventory. The air quality model predicts maximum differences in air pollutant concentrations that are located downwind from the central power plants that were removed from the domain. Maximum decreases in hourly peak ozone concentrations due to DER use are 10 ppb and are located over the state of New Jersey. Maximum decreases in 24-hr average fine particulate matter (PM2.5) concentrations reach 3 microg/m3 and are located off the coast of New Jersey and New York. The main contribution to decreased PM2.5 is the reduction of sulfate levels due to significant reductions in direct emissions of sulfur oxides (SO(x)) from the DER compared with the central power plants removed. The scenario presented here represents an accelerated DER penetration case with aggressive emission reductions due to removal of highly emitting power plants. Such scenario provides an upper bound for air quality benefits of DER implementation scenarios.  相似文献   

19.
Environmental Science and Pollution Research - Geothermal energy is considered environmentally friendly than fossil fuel sources, and geothermal power plants are expected to have a low carbon...  相似文献   

20.
Environmental Science and Pollution Research - The atmosphere security and regulation of climate change are being continuously highlighted as a pressing issue. The crisis of climate change owing to...  相似文献   

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