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991.
Perceiving the Environment from the Lay Perspective in Desertified Areas,Northern China 总被引:1,自引:0,他引:1
Investigating local people’s environmental perceptions can produce useful information that could be incorporated into decision
making processes that help resolve environmental problems. Although China is undergoing severe desertification, the perceptions
of the local people toward their degraded environment and the related issues have so far not been actively solicited. This
article, which is a supplement to Lee and Zhang’s (2004, 2005) studies, seeks to further investigate the lay public’s general environmental attitudes, perceptions of desertification, interpretations
of land-degrading activities, and particularly their interrelations in severely desertified areas. Minqin County in Gansu
Province, northern China, was chosen to be the study area. Data was collected via a questionnaire survey (n = 1138) administered in December 2002. Major findings were: (1) Most respondents had only weak altruistic environmental attitudes,
with educational level to be a significant determinant. (2) Respondents’ perceptions of desertification and interpretations
of land-degrading activities were contingent on personal attributes, general environmental attitudes, and other conceptions
related to desertification. It is recommended that the interrelations between the various aspects of the public’s environmental
perceptions should be thoroughly examined to facilitate their participation in environmental management. 相似文献
992.
Across the globe, continued policy debates regarding the management of old-growth forests center around the difficult task of balancing economic and ecological considerations. Though the forests of the Pacific Northwest United States are among the most studied old-growth ecosystems, ecological and economic analyses have yielded public land management directives that remain controversial. Specifically, the recently adopted Northwest Forest Plan lacks explicit goals for maintaining intergenerational equity for the use of forest resources and the diversity of old-growth ecosystems. Unlike previous studies which rely on monetary quantification of costs and benefits, this study develops and applies a conceptual framework for evaluating socially optimal Pacific Northwest old-growth forest utilization strategies. Conditions for the optimal management of old-growth forests are derived using dynamic programming. The objective function synthesizes relevant biological and economic attributes of the old-growth allocation problem. Results in the form of extraction paths are compared given social pressure for consumptive and non-consumptive benefits, as well as different planning horizons, rates of social time preference, and environmental variance. Lengthening the planning horizon results in a vast divergence of optimal policies in the absence of discounting. Extraction rates appear to approach zero as the planning horizon approaches infinity. While higher rates of social time preference increase the rate of extraction, forest stocks remaining at the terminal time period equal levels remaining with a lower discount rate. Increasing environmental variance results in a higher level of stock remaining at the terminal time period. This analysis, while specific to the old-growth controversy of the Pacific Northwest, does provide general guidelines for addressing similar problems of multiple uses of natural areas, particularly where such uses are mutually incompatible, or where one use may be irreversibly destructive to another. 相似文献
993.
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995.
Aerial measurement of radioxenon concentration off the west coast of Vancouver Island following the Fukushima reactor accident 总被引:1,自引:0,他引:1
Sinclair LE Seywerd HC Fortin R Carson JM Saull PR Coyle MJ Van Brabant RA Buckle JL Desjardins SM Hall RM 《Journal of environmental radioactivity》2011,102(11):1018-1023
In response to the Fukushima nuclear reactor accident, on March 20th, 2011, Natural Resources Canada conducted aerial radiation surveys over water just off the west coast of Vancouver Island. Dose-rate levels were found to be consistent with background radiation, however a clear signal due to 133Xe was observed. Methods to extract 133Xe count rates from the measured spectra, and to determine the corresponding 133Xe activity concentration, were developed. The measurements indicate that 133Xe concentrations on average lie in the range of 30-70 Bq/m3. 相似文献
996.
Water pollution is one of the major threats to public health in Pakistan. Drinking water quality is poorly managed and monitored. Pakistan ranks at number 80 among 122 nations regarding drinking water quality. Drinking water sources, both surface and groundwater are contaminated with coliforms, toxic metals and pesticides throughout the country. Various drinking water quality parameters set by WHO are frequently violated. Human activities like improper disposal of municipal and industrial effluents and indiscriminate applications of agrochemicals in agriculture are the main factors contributing to the deterioration of water quality. Microbial and chemical pollutants are the main factors responsible exclusively or in combination for various public health problems. This review discusses a detailed layout of drinking water quality in Pakistan with special emphasis on major pollutants, sources of pollution and the consequent health problems. The data presented in this review are extracted from various studies published in national and international journals. Also reports released by the government and non-governmental organizations are included. 相似文献
997.
以江苏历史文献记录的洪涝灾害为研究对象,分析历史时期江苏地区洪涝灾害发生的时空差异性特征,探讨影响洪涝灾害时空差异性的原因。时间尺度上,历史时期江苏地区洪涝灾害明清时期多发,集中于夏秋季节,其影响因素有长时间异常降水、风暴潮以及厄尔尼诺事件等。空间尺度上,洪涝灾害多发生于太湖平原、里下河平原及沿江地区。唐宋时期,太湖平原、沿江地区是江苏省洪涝灾害最为集中的地区,明代以降苏北平原洪涝灾害更为集中,原因应该是宋代太湖平原人口激增,涸湖造田破坏了太湖东泄水道,明清后泄洪能力得到提升,长江口的演变则使得沿江地区潮灾逐渐减少,而里下河平原因为黄河夺淮入海,导致泥沙沉降,水流不畅,成为洪涝走廊。 相似文献
998.
A huge tension exists between recognizing sustainable development (SD) as a meta-discourse and accepting a limitless interpretational width. We analyse the impacts of diversity of worldviews on the interpretation of SD—as a knowledge-based concept—through a critical literature review, resulting in recommendations on the topic. We apply a social-constructionist approach, appreciating the complex socio-ecological interactions at the heart of SD. Only recently worldviews are recognized as constitutive elements of SD. Little attention has been given to the impacts on generated knowledge for SD. Variety of worldviews induces a variety of knowledge claims and needs. To retain SD’s ‘universal’ appeal as practical decision-guiding strategy for policy and action, we propose an integrative approach towards knowledge for SD—entailing an explicit pluralization of knowledge. SD should be re-interpreted as a joint worldviews construct, embracing a diversity of views in collaborative research and co-production of knowledge. Interpreting SD as a joint endeavour is necessary to overcome historical obstacles like cultural hegemony and a hierarchy of knowledge systems. We identified the following requirements for an inclusive knowledge for SD paradigm: re-interpretation of SD as a worldview constructs in progress; interpretative flexibility; co-production of knowledge; subjectivity awareness and self-reflexivity; respect for a diversity of worldviews/knowledges; identifying shared goals; collaborative research; a systems approach; transdisciplinarity; and recognition of contextuality. Further research—concerning potential methodologies and typologies—to reconcile variety of worldviews and knowledge systems in a joint SD worldviews construct is urgently needed. 相似文献
999.
This paper provides details of a dynamic compartment model for estimating the (14)C radioactivity in an agricultural plant exposed to an amount of airborne (14)CO(2) gas. The plant, in the model, is divided into two compartments, the plant body (shoot and root) and ears, to predict the radioactivity of different parts of a plant. The carbon transports from, to and between the compartments are described by the processes of a photosynthesis, respiration, and translocation. The carbon transport fluxes of these processes are determined from the growth rates of a plant, which are usually easily attained. The model predictions showed that the present model could converge to a region where the specific activity model is applicable when the elapsed exposure time was extended up to the harvest time of a plant. The (14)C activity of a plant was greatly affected by the elapsed exposure time, the developmental stages of a plant at an exposure time, and the airborne (14)C activity during an exposure. It was expected that the peak of the ears' (14)C activity appeared when the exposure time was close to the ears-maturity date. The model predictions agreed reasonably well with the measured (14)C radioactivity of the rice plants that were artificially exposed to (14)CO(2) of a high (14)C source for a short period of time in an exposure box. 相似文献
1000.