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131.
旅游业常常被视为那些除阳光和沙滩外资源贫乏的国家“通往发达的护照”,它的迅猛发展已成为包括世界遗产点管理人员在内的众多人士主要关注的问题。远非持续发展模式的洲际旅游,可能会从那些现在必须为争取旅游业直接效益而拼搏,又没有忘记其长远代价的国家中更重要的优先领域抽走紧缺的资金。要达到世界遗产点保护与这样一些遗产点为每个人尤其当地居民之间的利益而进行的更好的平衡,将需要相当大的投资。 相似文献
132.
This paper extends the spatial local-likelihood model and the spatial mixture model to the space-time (ST) domain. For comparison,
a standard random effect space-time (SREST) model is examined to allow evaluation of each model’s ability in relation to cluster
detection. To pursue this evaluation, we use the ST counterparts of spatial cluster detection diagnostics. The proposed criteria
are based on posterior estimates (e.g., misclassification rate) and some are based on post-hoc analysis of posterior samples
(e.g., exceedance probability). In addition, we examine more conventional model fit criteria including mean square error (MSE).
We illustrate the methodology with a real ST dataset, Georgia throat cancer mortality data for the years 1994–2005, and a
simulated dataset where different levels and shapes of clusters are embedded. Overall, it is found that conventional SREST
models fair well in ST cluster detection and in goodness-of-fit, while for extreme risk detection the local likelihood ST
model does best. 相似文献
133.
Gerosa G Finco A Mereu S Vitale M Manes F Denti AB 《Environmental pollution (Barking, Essex : 1987)》2009,157(5):1737-1744
Ozone and energy fluxes have been measured using the eddy covariance technique, from June to December 2004 in Castelporziano near Rome (Italy), and compared to similar measurements made in the previous year. The studied ecosystem consisted in a typical Mediterranean Holm oak forest. Stomatal fluxes have been calculated using the resistance analogy and by inverting the Penmann-Monteith equation. Results showed that the average stomatal contribution accounts for 42.6% of the total fluxes. Non-stomatal deposition proved to be enhanced by increasing leaf wetness and air humidity during the autumnal months. From a comparison of the two years, it can be inferred that water supply is the most important limiting factor for ozone uptake and that prolonged droughts alter significantly the stomatal conductance, even 2 months after the soil water content is replenished. Ozone exposure, expressed as AOT40, behaves similarly to the cumulated stomatal flux in dry conditions whereas a different behaviour for the two indices appears in wet autumnal conditions. A difference also occurs between the two years. 相似文献
134.
The effect of the addition of spent grape marc compost (GMC) and vermicompost (GMV) as amendments to slate mining wastes was evaluated in a laboratory incubation experiment. Mixtures of slate processing fines (SPF), with three doses of each amendment (4%, 8% and 16% compost, dry weight), plus a control were incubated at 25 degrees C in the laboratory for 90 days. The changes in the chemical and biological properties of the mixtures (pH, total C, total N, inorganic N, available nutrients, microbial biomass carbon and dehydrogenase activity) were investigated during the incubation period, and once it was finished, the phytotoxicity of the mixtures was determined by the germination of Lolium multiflorum Lam. seeds. The addition of the amendments significantly increased the nutrient concentrations of the SPF and enhanced biological activity by increasing microbial biomass and enzymatic activity. Results improved with higher doses; within the composts, GMV showed a better performance than GMC. These results prove the suitability of grape marc-derived amendments for the biochemical amelioration of mining wastes, and highlight the benefits of organic amendment in restoration projects. 相似文献
135.
即使其它方面只是相同或略好一些,只要能使车辆的效率提高到现在的4-8倍,就会有助于许多问题的解决,诸如空气质量、油料使用、陈旧的产业结构,以及能源(特别是电力)供应等大问题,运输生产技术的变革具有成为世界环境与经济发展重要源泉的潜力。革命性的开发已经在主要的汽车制造国家进行。这些技术变革也为其它国家的大踏步发展提供了一次机遇。 相似文献
136.
Different multivariate statistical analysis such as, cluster analysis, principal component analysis, and multidimensional
scale plot were employed to evaluate the trophic status of water quality for four monitoring stations. The present study was
carried out to determine the physicochemical parameters of water and sediment characteristics of Pondicherry mangroves—southeast
coast of India, during September 2008–December 2010. Seasonal variations of different parameters investigated were as follows:
salinity (10.26–35.20 psu), dissolved oxygen (3.71–5.33 mg/L), pH (7.05–8.36), electrical conductivity (26.41–41.33 ms−1), sulfide (1.98–40.43 mg/L), sediment texture sand (39.54–87.31%), silt (9.89–32.97%), clay (3.06–31.20%), and organic matter
(0.94–4.64%). pH, temperature, salinity, sand, silt, clay, and organic matter indicated a correlation at P < 0.01. CA grouped the four seasons in to four groups (pre-monsoon, monsoon, post-monsoon, summer) and the sampling sites
in to three groups. PCA identified the spatial and temporal characteristics of trophic stations and showed that the water
quality was worse in stations 3 and 4 in the Pondicherry mangroves. 相似文献
137.
Biomonitoring of multi-element atmospheric deposition using terrestrial moss is a well-established technique in Europe. Although
the technique is widely known, there were very limited records of using this technique to study atmospheric air pollution
in Malaysia. In this present study, the deposition of 11 trace metals surrounding the main petroleum refinery plant in Kerteh
Terengganu (eastern part of peninsular Malaysia) has been evaluated using two local moss species, namely Hypnum plumaeforme and Taxithelium instratum as bioindicators. The study was also done by means of observing whether these metals are attributed to work related to oil
exploration in this area. The moss samples have been collected at 30 sampling stations in the vicinity of the petrochemical
industrial area covering up to 15 km to the south, north, and west in radius. The contents of heavy metal in moss samples
were analyzed by energy dispersive x-ray fluorescence technique. Distribution of heavy metal content in all mosses is portrayed
using Surfer software. Areas of the highest level of contaminations are highlighted. The results obtained using the principal
components analysis revealed that the elements can be grouped into three different components that indirectly reflected three
different sources namely anthropogenic factor, vegetation factor, and natural sources (soil dust or substrate) factor. Heavy
metals deposited mostly in the distance after 9 km onward to the western part (the average direction of wind blow). V, Cr,
Cu, and Hg are believed to have originated from local petrochemical-based industries operated around petroleum industrial
area. 相似文献
138.
More than 1.5 million people live in the Kathmandu valley. The valley is facing an extreme shortage of water supply. At the same time the demand is escalating rapidly. To address this issue of scarcity of water, the government of Nepal has proposed a project of inter-basin transfer of water from Melamchi River located 40 km north-east of the Kathmandu valley. The project will cover two districts and three municipalities and will potentially have significant impacts on the environment. In accordance with the Environmental Protection Regulation of Nepal (1997), the Melamchi Water Supply Project (MWSP) has undergone an EIA during the feasibility study stage of the proposed project. The recommendations contained in the EIA were integrated into the project design for implementation in 2006. This paper summarizes the background of MWSP, the environmental concerns described in the EIA and the status of Environmental Management Plan (EMP) developed to address environmental compliance and other issues involving participation and support of the local people. This paper also provides some lessons to learn on the modalities of addressing the demands and grievances of the local people concerning environmental management. 相似文献
139.
Geochemistry in the modern soil survey program 总被引:1,自引:0,他引:1
Wilson MA Burt R Indorante SJ Jenkins AB Chiaretti JV Ulmer MG Scheyer JM 《Environmental monitoring and assessment》2008,139(1-3):151-171
Elemental analysis has played an important role in the characterization of soils since inception of the soil survey in the
US. Recent efforts in analysis of trace and major elements (geochemistry) have provided necessary data to soil survey users
in a variety of areas. The first part of this paper provides a brief overview of elemental sources, forms, mobility, and bioavailability;
critical aspects important to users of soil survey geochemical data for appropriate use and interpretations. Examples are
provided based on data gathered as part of the US soil survey program. The second part addresses the organization of sample
collection in soil survey and how soil surveys are ideally suited as a sampling strategy for soil geochemical studies. Geochemistry
is functional in characterization of soil types, determining soil processes, ecological evaluation, or issues related to soil
quality and health, such as evaluating suitability of soils for urban or agricultural land use. Applications of geochemistry
are on-going across the US and are documented herein. This analytical direction of soil survey complements historic efforts
of the National Cooperative Soil Survey Program and addresses the increasing need of soil survey users for data that assists
in understanding the influence of human activities on soil properties. 相似文献
140.
Electrokinetic remediation of organochlorines in soil: enhancement techniques and integration with other remediation technologies 总被引:1,自引:0,他引:1
Electrokinetic remediation has been increasingly used in soils and other matrices for numerous contaminants such as inorganic, organic, radionuclides, explosives and their mixtures. Several strategies were tested to improve this technology effectiveness, namely techniques to solubilize contaminants, control soil pH and also couple electrokinetics with other remediation technologies. This review focus in the experimental work carried out in organochlorines soil electroremediation, aiming to systemize useful information to researchers in this field. It is not possible to clearly state what technique is the best, since experimental approaches and targeted contaminants are different. Further research is needed in the application of some of the reviewed techniques. Also a number of technical and environmental issues will require evaluation for full-scale application. Removal efficiencies reported in real contaminated soils are much lower than the ones obtained with spiked kaolinite, showing the influence of other factors like aging of the contamination and adsorption to soil particles, resulting in important challenges when transferring technologies into the field. 相似文献