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771.
A unique pastoral community uses the arid rangelands of eastern Ladakh, known as Changthang, northern India. The nomadic people rear a variety of livestock such as sheep, goats, horses and yaks, which provide them with various goods and services. Nevertheless, the needs and aspirations of the people are changing. There is a trend towards increasing the livestock population, especially of a breed of goat that produces one of the finest natural fibres: Pashmina, which is the mainstay of their economy. This increase in goat population, however, is jeopardising the long‐term survival of the wild herbivores in the region, and as such is not sustainable. We present information on the current trends in socio‐economy, Pashmina production, wildlife conservation, and the conflicts of interest between wildlife and nomads in the region. On the basis of this information, we make suggestions for the conservation of natural resources in the region. We recommend preserving the historical societal norms and notions of the people, and capitalising on them to manage natural resources. We also recommend joint management of natural resources by the local people, State and non‐governmental organisations. Our findings provide a platform on which a grazing policy for the region may be formulated. 相似文献
772.
Citizens’ Views on Farm Animal Welfare and Related Information Provision: Exploratory Insights from Flanders,Belgium 总被引:1,自引:0,他引:1
Filiep Vanhonacker Els Van Poucke Frank Tuyttens Wim Verbeke 《Journal of Agricultural and Environmental Ethics》2010,23(6):551-569
The results of two independent empirical studies with Flemish citizens were combined to address the problem of a short fall
of information provision about higher welfare products. The research objectives were (1) to improve our understanding of how
citizens conceptualize farm animal welfare, (2) to analyze the variety in the claimed personal relevance of animal welfare
in the food purchasing decision process, and (3) to find out people’s needs in relation to product information about animal
welfare and the extent to which the current information caters to these needs. The first study consisted of a survey conducted
in three consecutive years (2000–2002, n = 521) and was complemented with more recent qualitative data from four focus group discussions (2006, n = 29). Citizens’ conceptualization of farm animal welfare matched reasonably well with those in the scientific literature,
although it is clearly influenced by a lower level of practical experience and a higher weight of empathy. In general, respondents
indicated that animal welfare was an important product attribute, although it was less important than primary product attributes
such as quality, health, and safety. Moral issues, rather than a perception of higher quality, were the main influence on
preferences for higher welfare products. At present, higher standards of animal welfare are mostly guaranteed within more
general quality assurance schemes. Yet people’s decisions to not choose higher welfare products seems to be related to the
perceptual disconnection between eating animal food products and the living producing animals. Respondents generally thought
better information provision was required and the present level of provision was strongly criticized. In combination, the
findings of both studies help inform the discussion about how citizens can be informed about animal welfare and the preferred
content, source, and medium of such information. The paper also provides insights into citizens’ semantic interpretation of the concept of animal welfare (what wordings they use) and the range of relevance that animal welfare has for different groups that, in turn is useful in identifying which segments can be targeted. This can contribute to a more effective valorization of animal welfare as a product attribute. 相似文献
773.
Hatch L Clark C Merrick R Van Parijs S Ponirakis D Schwehr K Thompson M Wiley D 《Environmental management》2008,42(5):735-752
In 2006, we used the U.S. Coast Guard’s Automatic Identification System (AIS) to describe patterns of large commercial ship
traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial
vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of
the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston
Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We
combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months
in 2006. Analysis of received sound levels (10–1000 Hz, root-mean-square pressure re 1 μPa ± SE) averaged 119.5 ± 0.3 dB at
high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the
majority of the time period analyzed. Average source level estimates (71–141 Hz, root-mean-square pressure re 1 μPa ± SE)
for individual vessels ranged from 158 ± 2 dB (research vessel) to 186 ± 2 dB (oil tanker). Tankers were estimated to contribute
2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results
indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers
regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
774.
Water Footprint of the Palestinians in the West Bank1 总被引:1,自引:0,他引:1
Dima W. Nazer Maarten A. Siebel Pieter Van der Zaag Ziad Mimi Huub J. Gijzen 《Journal of the American Water Resources Association》2008,44(2):449-458
Abstract: Water in the West Bank of Palestine is a key issue due to its limited availability. Water is used from own sources for domestic, industrial, and agricultural purposes. Moreover, water is consumed in its virtual form through consumption of imported goods, such as crops and livestock, the production of which used water in the country of production. In addition, wastewater in many parts of the West Bank is disposed off without treatment into the wadis, deteriorating the quality of the water resources in the area and, therefore, further reducing the quantity of good quality water available. This paper calculates the water footprint for the West Bank. The consumption component of the water footprint of the West Bank was found to be 2,791 million m3/year. Approximately 52% of this is virtual water consumed through imported goods. The West Bank per capita consumption component of the water footprint was found to be 1,116 m3/cap/year, while the global average is 1,243 m3/cap/year. Out of this number 50 m3/cap/year was withdrawn from water resources available in the area. Only 16 m3/cap/year (1.4%) was used for domestic purposes. This number is extremely low and only 28% of the global average and 21% of the Israeli domestic water use. The contamination component of the water footprint was not quantified but was believed to be many times larger than the consumption component. According to the official definition of water scarcity, the West Bank is suffering from a severe water scarcity. Therefore, there is a need for a completely new approach towards water management in the West Bank, whereby return flows are viewed as a resource and that is geared towards a conservation oriented approach of “use, treat, and reuse.” 相似文献
775.
Spills in the nuclear fuel cycle have led to soil contamination with uranium. In case of small contamination just above release levels, low-cost yet sufficiently efficient remedial measures are recommended. This study was executed to test if low-level U contaminated sandy soil from a nuclear fuel processing site could be phytoextracted in order to attain the required release limits. Two soils were tested: a control soil (317 Bq 238U kg(-1)) and the same soil washed with bicarbonate (69 Bq 238U kg(-1)). Ryegrass (Lolium perenne cv. Melvina) and Indian mustard (Brassica juncea cv. Vitasso) were used as test plants. The annual removal of soil activity by the biomass was less than 0.1%. The addition of citric acid (25 mmol kg(-1)) 1 week before the harvest increased U uptake up to 500-fold. With a ryegrass and mustard yield of 15,000 and 10,000 kg ha(-1), respectively, up to 3.5% and 4.6% of the soil activity could be removed annually by the biomass. With a desired activity reduction level of 1.5 and 5 for the bicarbonate-washed and control soil, respectively, it would take 10-50 years to attain the release limit. However, citric acid addition resulted in a decreased dry weight production. 相似文献
776.
Vangronsveld J Colpaert JV Van Tichelen KK 《Environmental pollution (Barking, Essex : 1987)》1996,94(2):131-140
In 1990, 3 ha of a highly metal polluted acid sandy soil at the site of a former pyrometallurgical zinc smelter was treated with a combination of beringite and compost; beringite is a substance that has a strong metal immobilization capacity. After soil treatment and sowing of a mixture of metal-tolerant Agrostis capillaris and Festuca rubra, a healthy vegetation cover developed. Five years later, an evaluation was made of soil physico-chemical parameters, potential phytotoxicity, floristic and fungal diversity and mycorrhizal infection of the plant community. Phytotoxicity was shown to be maintained at the low level observed immediately after soil treatment. The water-extractable metal fraction of the treated soil was up to 70 times lower compared to the non-treated soil. The vegetation was still healthy and regenerating by vegetative means and by seed. Diversity of higher plant species and saprophytic fungi was extremely low in the untreated area due to the high soil toxicity and the absence of metal tolerant ecotypes of plants and fungi. On the treated soil, in contrast, the species richness of higher plants was much higher; several perennial forbs which are not noted as metal tolerant had colonized the revegetated area. Most of these species belong to mycotrophic families so that the presence of a mycorrhizal network in the soil promotes their establishment. The ubiquity of the mycorrhizal fungi in the roots showed that a functioning ecosystem was establishing. In non-treated soil, the mycorrhizal infection rates of the roots were consistently lower during the whole growing season. 相似文献
777.
Van den Steen E Covaci A Jaspers VL Dauwe T Voorspoels S Eens M Pinxten R 《Environmental pollution (Barking, Essex : 1987)》2007,148(2):648-653
In this study we investigated the accumulation, tissue-specific distribution and possible debromination of BDE 209 in a terrestrial songbird species, the European starling, using silastic implants as a method of exposure. BDE 209 accumulated in the blood of the exposed starlings to a mean peak concentration of 16+/-4.1 ng/ml on day 10. After this peak, there was a decline to 3.3+/-0.4 ng/ml blood at the end of the exposure period of 76 days, which suggests elimination of BDE 209. In the exposed group, the muscle concentrations (461 ng/g lipid weight [lw], 430 ng/g lw) were about twofold those in liver (269 ng/g lw, 237 ng/g lw). In addition to BDE 209, other PBDE congeners, particularly octa- and nonaBDEs, were also present in the muscle and liver, suggesting bioformation from BDE 209. To our knowledge, these results are the first indications for the debromination of BDE 209 in birds. 相似文献
778.
The contribution of particles washed from rooftops to contaminant loading to urban streams 总被引:4,自引:0,他引:4
Rooftops are both a source of and a pathway for contaminated runoff in urban environments. To investigate the importance of particle-associated contamination in rooftop runoff, particles washed from asphalt shingle and galvanized metal roofs at sites 12 and 102 m from a major expressway were analyzed for major and trace elements and PAHs. Concentrations and yields from rooftops were compared among locations and roofing material types and to loads monitored during runoff events in the receiving urban stream to evaluate rooftop sources and their potential contribution to stream loading. Concentrations of zinc, lead, pyrene, and chrysene on a mass per mass basis in a majority of rooftop samples exceeded established sediment quality guidelines for probable toxicity of bed sediments to benthic biota. Fallout near the expressway was greater than farther away, as indicated by larger yields of all contaminants investigated, although some concentrations were lower. Metal roofing was a source of cadmium and zinc and asphalt shingles a source of lead. The contribution of rooftop washoff to watershed loading was estimated to range from 6 percent for chromium and arsenic to 55 percent for zinc. Estimated contributions from roofing material to total watershed load were greatest for zinc and lead, contributing about 20 and 18 percent, respectively. The contribution from atmospheric deposition of particles onto rooftops to total watershed loads in stormwater was estimated to be greatest for mercury, contributing about 46 percent. 相似文献
779.
Abatement and degradation pathways of toluene in indoor air by positive corona discharge 总被引:14,自引:0,他引:14
Indoor air concentrations of volatile organic compounds often exceed outdoor levels by a factor of 5. There is much interest in developing new technologies in order to improve indoor air quality. In this work non-thermal plasma (DC positive corona discharge) is explored as an innovative technology for indoor air purification. An inlet gas stream of 10 l min(-1) containing 0.50+/-0.02 ppm toluene was treated by the plasma reactor in atmospheric conditions. Toluene removal proved to be achievable with a characteristic energy density epsilon(0) of 50 J l(-1). Removal efficiencies were higher for 26% relative humidity (epsilon(0)=35 J l(-1)), compared with those at increased humidities (50% relative humidity, epsilon(0)=49 J l(-1)). Reaction products such as formic acid, benzaldehyde, benzyl alcohol, 3-methyl-4-nitrophenol, 4-methyl-2-nitrophenol, 4-methyl-2-propyl furan, 5-methyl-2-nitrophenol, 4-nitrophenol, 2-methyl-4,6-dinitrophenol are identified by means of mass spectrometry. Based on these by-products a toluene degradation mechanism is proposed. 相似文献
780.
Yu YX Huang NB Zhang XY Li JL Yu ZQ Han SY Lu M Van de Wiele T Wu MH Sheng GY Fu JM 《Chemosphere》2011,83(2):152-160
The concentrations of PBDEs in 299 vegetable and animal-based food samples of 31 species, collected in Shanghai, China, and the bioaccessibility of PBDEs in part of the samples were determined. The PBDE concentrations ranged from 0 to 1245.4 pg g−1 with animal-based food containing more PBDEs than vegetables. The bioaccessibility of PBDEs, determined by a method simulating human gastrointestinal digestion process, were from 2.6% to 39.9% in vegetables, and from 5.2% to 105.3% in animal-based food. For animal-based food, good correlations were observed between the bioaccessibility of PBDEs and the fat content, thus the fat content in animal-based food was able to be used to estimate the bioaccessibility of PBDEs. The total daily intake of PBDEs via ingestion of vegetables and animal-based food for an average Shanghai resident was estimated as 13 235.7 and 13 668.0 pg d−1, respectively, but the amounts available for human absorption were reduced to 2674.4 and 4316.6 pg d−1 after the PBDE bioaccessibility was considered. Finally, the contributions of different food groups to the total daily intake of PBDEs were evaluated. The results revealed that, when not considering the bioaccessibility of PBDEs, vegetables were the leading contributor (49.2%), followed by fish (34.0%). However, the sequence was reversed after the PBDE bioaccessibility was taken into account. The results indicated that human exposure to PBDEs via food ingestion might have been significantly overestimated and the exposure assessment could be misleading if the bioaccessibility of PBDEs was not considered. 相似文献