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731.
"低碳生活"是一种通过降低碳的排放减少对大气的污染,进而建立起来的发展持续型和环境友好型的全新生活方式,其核心内容是低污染、低消耗和低排放,以及多节约。"低碳生活"是低碳社会的重要组成部分。日常生活中"低碳生活"的实现途径主要是节电、节气和回收。 相似文献
732.
Mac Nally R 《Journal of environmental management》2008,88(4):1202-1211
Many native bird species in production landscapes of south-eastern Australia demonstrably are declining, with loss of native vegetation as the major cause. Our biodiversity management objectives must be to increase the probabilities of persistence of birds that should occur in the landscape. To do so, there needs to be extensive amounts of new plantings. However, one must be conscious that: (1) new plantings in the impoverished soils and increasing aridity of southern Australia will take many decades to mature, and, also, will offer suitable habitats for a sequence of different species over the course of that maturation process; and (2) much existing vegetation is senescent or will be in a few decades' time. Recent landscape rebuilding models do not explicitly consider maturation time-lags. These hystereses in habitat maturation may create 'bottlenecks' at future times (e.g. in 50yr) that might prevent some species from persisting in whole landscapes even though such landscapes may be much more suitable in 100yr than now. There are several critical issues: (1) species differ in habitat needs and even one species may require different kinds of habitats for foraging and for breeding; (2) landscapes must be conceived, and managed, as spatial and temporal mosaics to allow for persistence of the full set of species that should occupy them, meaning that senescing and replanted habitats may need to be juxtaposed; and (3) in certain particularly problematic landscapes, some highly productive agricultural lands may need to be used for providing habitat because maturation can be fast-tracked in fertile, well-watered locations. The problem is a complex one of scheduling and placement, and its optimization presents major theoretical and analytical challenges. 相似文献
733.
Efroymson RA Peterson MJ Giffen NR Ryon MG Smith JG Hargrove WW Roy WK Welsh CJ Druckenbrod DL Quarles HD 《Journal of environmental management》2008,88(4):1452-1470
Habitat valuation methods were implemented to support remedial decisions for aquatic and terrestrial contaminated sites at the East Tennessee Technology Park (ETTP) on the US Department of Energy (DOE) Oak Ridge Reservation in Oak Ridge, TN, USA. The habitat valuation was undertaken for six contaminated sites: Contractor's Spoil Area, K-901-N Disposal Area, K-770 Scrapyard, K-1007-P1 pond, K-901 pond, and the Mitchell Branch stream. Four of these sites are within the industrial use area of ETTP and two are in the Black Oak Ridge Conservation Easement. These sites represent terrestrial and aquatic habitat for vertebrates, terrestrial habitat for plants, and aquatic habitat for benthic invertebrates. Current and potential future, no-action (no remediation) scenarios were evaluated primarily using existing information. Valuation metrics and scoring criteria were developed in a companion paper, this volume. The habitat valuation consists of extensive narratives, as well as scores for aspects of site use value, site rarity, and use value added from spatial context. Metrics for habitat value were expressed with respect to different spatial scales, depending on data availability. There was significant variation in habitat value among the six sites, among measures for different taxa at a single site, between measures of use and rarity at a single site, and among measures for particular taxa at a single site with respect to different spatial scales. Most sites had aspects of low, medium, and high habitat value. Few high scores for current use value were given. These include: wetland plant communities at all aquatic sites, Lepomid sunfish and waterbirds at 1007-P1 pond, and Lepomid sunfish and amphibians at K-901 pond. Aquatic sites create a high-value ecological corridor for waterbirds, and the Contractor's Spoil Area and possibly the K-901-N Disposal Site have areas that are part of a strong terrestrial ecological corridor. The only example of recent observations of rare species at these sites is the gray bat observed at the K-1007-P1 pond. Some aspects of habitat value are expected to improve under no-action scenarios at a few of the sites. Methods are applicable to other contaminated sites where sufficient ecological data are available for the site and region. 相似文献
734.
Douglas S. Kenney Christopher Goemans Roberta Klein Jessica Lowrey Kevin Reidy 《Journal of the American Water Resources Association》2008,44(1):192-207
Abstract: Residential water demand is a function of several factors, some of which are within the control of water utilities (e.g., price, water restrictions, rebate programs) and some of which are not (e.g., climate and weather, demographic characteristics). In this study of Aurora, Colorado, factors influencing residential water demand are reviewed during a turbulent drought period (2000‐2005). Findings expand the understanding of residential demand in at least three salient ways: first, by documenting that pricing and outdoor water restriction policies interact with each other ensuring that total water savings are not additive of each program operating independently; second, by showing that the effectiveness of pricing and restrictions policies varies among different classes of customers (i.e., low, middle, and high volume water users) and between predrought and drought periods; and third, in demonstrating that real‐time information about consumptive use (via the Water Smart Reader) helps customers reach water‐use targets. 相似文献
735.
Annik Schnitzler Jean-Claude Génot Maurice Wintz Brack W. Hale 《Journal of Agricultural and Environmental Ethics》2008,21(5):423-436
This article discusses the ecological and cultural criteria underlying the management practices for protected areas in France.
It examines the evolution of French conservation from its roots in the 19th century, when it focused on the protection of
scenic landscapes, to current times when the focus is on the protection of biodiversity. However, biodiversity is often socially
defined and may not represent an ecologically sound objective for conservation. In particular, we question the current approach
to protecting a specific type of biodiversity that is at the basis of traditional landscape but does not value systems that
are left to develop naturally (i.e., without significant human intervention). We present several examples of current attempts
in France and Europe to managing traditional ecosystems and then discuss the values that exist in systems that develop naturally.
We feel the latter systems often have much to offer in terms of biodiversity as well as providing important sites for the
study of dynamic ecological communities in an ever-changing world. 相似文献
736.
Mugu Lagoon is an estuary in southern California, listed as impaired for mercury. In 2005, we examined mercury cycling at ten sites within at most four habitats. In surface water (unfiltered and filtered) and pore water, the concentration of total mercury was correlated with methylmercury levels (R2=0.29, 0.26, 0.27, respectively, p<0.05), in contrast to sediments, where organic matter and reduced iron levels were most correlated with methylmercury content (R2=0.37, 0.26, respectively, p<0.05). Interestingly, levels for percent methylmercury of total mercury in sediments were higher than typical values for estuarine sediments (average 5.4%, range 0.024-38%, n=59), while pore water methylmercury Kd values were also high (average 3.1, range 2.0-4.2l kg(-1), n=39), and the estimated methylmercury flux from sediments was low (average 1.7, range 0.14-5.3ng m(-2) day(-1), n=19). Mercury levels in predatory fish tissue at Mugu are >0.3ppm, suggesting biogeochemical controls on methylmercury mobility do not completely mitigate methylmercury uptake through the food web. 相似文献
737.
工业厂房自然通风的数值模拟及结构改进 总被引:3,自引:0,他引:3
采用计算流体动力学(CFD)技术(方法)对某钢铁厂房的自然通风过程进行数值模拟研究。采用Realizable k-ε湍流模型及DO辐射模型对该工业厂房的流场和温度场进行了数值计算,其计算结果与文献中实验值的对比吻合很好。在该基础上,进一步对热源分布和进风口、天窗排风口结构对自然通风效果的影响做了计算,结果表明:适当的减小排风口高度以及缩短生产线热源的间距等能够在一定程度上改善自然通风的效果。研究成果为工业厂房自然通风系统的设计提供了理论参考依据。 相似文献
738.
The theoretical concept, “asset specificity,” is applied to real data in the context of Danish nature conservation network
planning in order to produce illustrative examples of an economic measure of the network’s vulnerability to exogenous shocks
to the species composition. Three different measures of asset specificity are quantified from the shadow value of eliminating
a key species from the individual grid cells. This represents a novel approach and a different interpretation of the term,
as it is conventionally used as a qualitative indicator in the transaction cost economics literature. Apart from supplementing
existing cost measures with an indicator of risk associated with investments in protected areas, this study demonstrates how
the estimation and interpretation of various asset specificity measures for geographical areas may qualify policy makers’
choice of policy instrument in conservation planning. This differs from the more intuitive approach of basing policy instrument
choice solely on the rarity of the species in a given area. 相似文献
739.
This paper explains briefly the conceptual framework of an ecosystem-based multiple-use forest management planning focusing on biodiversity conservation and participation. Some results from a case study were documented to realize the implementation of the concept. A strong liaison between the related institutions and major stakeholders and the effective use of Geographic Information System (GIS) and Remote Sensing (RS) are necessary. Effective participation is evident only with the involvement of enthusiastic and skillful stakeholders. A case study of ??neada, Turkey, supported the idea that participation as communication has better possibilities to promote multiple-use forest management than participation as information gathering. Primary challenges relate to the effectiveness of conservation program, availability of coherent biodiversity data, capacity building; awareness, training, and common understanding of biodiversity and protected area concept; coordination among the related institutions and stakeholders; and willingness and enthusiasm of authorities to accept and implement the concept. 相似文献
740.
Krishna Prasad Vadrevu K. V.S. Badarinath Anuradha Eaturu 《Journal of Environmental Planning and Management》2008,51(6):817-832
Information on fires in different geographic regions of India is relatively scarce. This study quantifies spatial and temporal patterns in fire occurrences covering different states and districts in India. Two important scientific questions are answered in this study: (1) how are the fire events distributed across different geographical regions? (2) are there any specific districts where fire events clustered across space and time? To address these questions, Along Track Scanning Radiometer (ATSR) derived satellite fire counts from 1997–2006 were used and the datasets were analysed using spatial scan statistic. Spatial scan statistic provides a test statistic for most likely ‘hotspot’ spatial clusters, based on the likelihood ratio test and Monte Carlo simulation. Results from geographical analysis based on state boundaries suggested Maharastra state had the highest number of fires followed by Madhya Pradesh, Chattisgarh, Orissa, etc., during the 10-year period. Among the several districts, the spatial scan statistic identified the most likely cluster of fire events in Dausa, Karauli, Sawai Madhopur, Bharatpur and Alwar in addition to several other secondary clusters, with high statistical significance. These results are based on a large sample of cases, and they provide convincing evidence of spatial clustering of fire events in the Indian region. Results relating to hotspot areas of fire risk can guide policy makers towards the best management strategies for avoiding damages to forests, human life and personal property in the ‘hotspot’ districts. 相似文献