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101.
The objective of this study was to determine the levels of major phytotoxic metals―including cadmium (Cd), copper (Cu), nickel (Ni), and zinc (Zn)―in agricultural soils of Western Macedonia, Greece. We also wanted to determine the possible relationships among elements and between soil properties and elemental concentrations. Surface soil samples, n = 570, were collected and analyzed. The results of the elemental analysis showed that the mean metal concentrations were consistent with reported typical concentrations found in Greek agricultural soils in the cases of Zn and Cu. Cd exhibited lower and Ni higher mean concentrations than the typical levels reported in the literature. Metal concentrations in the majority of the examined samples (>69%) were found to be higher than the respective critical plant-deficiency levels. However, only 0.4% and 0.2% of the analyzed soil samples, respectively, exhibited Cd and Ni concentrations higher than the levels that cause plant toxicity, as referenced by other investigators. These results suggest that the soils studied can be considered as unpolluted with respect to the examined food-chain metal contaminants. However, the levels of the metal concentrations in some of the soil samples, and the low correlation of the metals with soil properties, suggest an anthropogenic rather that lithogenic origin.  相似文献   
102.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294 Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being promoted by UNIDO′s Cleaner Production Programme. Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved through the development of company specific business models that implement the above-indicated Chemical Leasing concept with the support from the Mexican National Cleaner Production Centre (NCPC). Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project, several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners. The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach to International Chemicals Management (SAICM) Preparation Conference in Vienna. Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level, UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical Leasing projects and work programmes.  相似文献   
103.
Background Due to the bovine spongiform encephalopathy (BSE), specified risk material (SRM) as well as animal meat and bone meal (MBM) are banned from the food and feed chain because of a possible infection with pathogenic prions (PrPSc). Nowadays, prions are widely accepted to be responsible for TSE(transmissible spongiform encephalopathies)-caused illnesses like BSE and scrapie, and especially for the occurrence of the new variant of CJD in humans. Presently, SRM and MBM are burnt under high temperatures to avoid any hazards for humans, animals or the environment. The aim of this study was to evaluate a method using animal fat separated from Category I material which includes SRM and the carcasses of TSE-infected animals, or animals suspected of being infected with TSE, as a source for producing biodiesel by transesterification, analogous to the biodiesel process using vegetable oil. Methods For this purpose, animal fat was spiked with scrapie-infected hamster brain equivalents – as representative for a TSE-infected animal – and the biodiesel manufacturing process was downscaled and performed under lab-scale conditions. Results and Discussion The results analysed by Western blotting showed clearly that almost each single step of the process leads to a significant reduction of the concentration of the pathogenic prion protein (PrPSc) in the main and side-products. Conclusion The data revealed that the biodiesel production, even from material with a high concentration of pathogenic prions, can be considered as safe. Recommendations and Outlook The obtained results indicated that biodiesel produced from prion-contaminated fat was safe under the tested process conditions. However, it has to be pointed out that the results cannot be generalized because a different process control using other conditions may lead to different results and then has to be analysed independently. It is clear that the production of biodiesel from high risk material represents a more economic usage than the combustion of such material.  相似文献   
104.
Numerous empirical and simulation-based studies have documented or estimated variable impacts to the economic growth of nation states due to the adoption of domestic climate change mitigation policies. However, few studies have been able to empirically link projected changes in economic growth to the provision of public goods and services. In this research, we couple projected changes in economic growth to US states brought about by the adoption of a domestic climate change mitigation policy with a longitudinal panel dataset detailing the production of outdoor recreation opportunities on lands managed in the public interest. Joining empirical data and simulation-based estimates allow us to better understand how the adoption of a domestic climate change mitigation policy would affect the provision of public goods in the future. We first employ a technical efficiency model and metrics to provide decision makers with evidence of specific areas where operational efficiencies within the nation's state park systems can be improved. We then augment the empirical analysis with simulation-based changes in gross state product (GSP) to estimate changes to the states’ ability to provide outdoor recreation opportunities from 2014 to 2020; the results reveal substantial variability across states. Finally, we explore two potential solutions (increasing GSP or increasing technical efficiency) for addressing the negative impacts on the states’ park systems operating budgets brought about by the adoption of a domestic climate change mitigation policy; the analyses suggest increasing technical efficiency would be the most viable solution if/when the US adopts a greenhouse gas reduction policy.  相似文献   
105.
Are elected politicians primarily motivated by holding office, thus choosing environmental policies accordingly? Or are they motivated by the chance to implement their preferred environmental policies? Do governors have character, in the sense that they promise and implement environmental policies consistent with their own preferences? To answer these questions, we study the differences in environmental spending across both re-electable and lame duck governors from the two main political parties. In our empirical analysis, we make use of parametric and non-parametric regression-discontinuity approaches. While re-electable governors do not set significantly different policies, lame duck governors do. We argue that in the area of environmental policy governors appear to be primarily office motivated and lack character.  相似文献   
106.
Integrated catchment management (ICM) was introduced as state policy in 1988 to overcome land and water degradation in Western Australia (WA). Key elements of ICM are cooperation among state and local governments and landholders; involvement of landholders and local communities in identification of issues and solutions; and, agreement on common objectives. This study identifies the issues that led to the adoption of integrated catchment management in Western Australia, outlines its main characteristics, and reviews the progress and problems encountered during its initial implementation. ICM has generally been accepted and endorsed in WA. However, differences of opinion have emerged regarding exactly what it means and how it should be applied. Designing ideal organizational structures for ICM is not sufficient for it to be effective. Ultimately, people have to make ICM function, and therefore it is essential that priority be given to cultivating the good will and trust necessary for ICM to work well. ICM also requires a long-term perspective and appreciation that it requires many people and agencies to move out of current “comfort zones.” As a result, initial implementation of ICM usually will encounter turbulence and debate.  相似文献   
107.
ABSTRACT: Recognition of the flood hazard that exists on alluvial fans has seriously lagged behind the recognition of other more conventional flood hazards such as those associated with most rivers. This delay in recognition was due, until recently, to a general lack of economic investment and development in these areas and a concomitant lack of historical alluvial fan flood damage. Dramatic recent events, such as Tropical Storm Kathleen, emphasized to the Federal Insurance Administration (FIA) the need for developing an appropriate methodology to identify flood hazard areas on alluvial fans. This paper presents the methodology now employed by FIA as well as flood plain management considerations that could reduce future flood related damage to communities developing in these areas.  相似文献   
108.
109.
/ The coastal zone of the Indian Ocean is coming under increasing pressure from human activities. Australia may be one of the few countries in this region that can afford to take adequate conservation measures in the near future. As it also has one of the longest Indian Ocean coastlines, Australia has the opportunity, and responsibility, to make a meaningful contribution to the conservation of Indian Ocean biodiversity. Threatened species, including marine turtles, inshore dolphins, and dugongs are an important component of that biodiversity. The dugong has been exterminated from several areas in the Indian Ocean, and it appears to be particularly threatened by mesh netting andhunting. Its long-term survival may depend on adequate protection in Australia, which contains the largest known Indian Ocean populations. This protection will require, in part, an appropriate system of marine protected areas (MPAs). This paper examines the adequacy of MPAs along Australia's Indian Ocean coast. Dugongs occur in two MPAs in Western Australia. The proposed expansion of the system of marine reserves is based primarily on representative samples of ecosystems from each biogeographic region. It is inadequate because it does not take into account the distribution and relative abundance of threatened species. If the conservation of biodiversity is to be maximized, the system of MPAs should incorporate both representativeness and the needs of threatened species. The level of protection provided by MPAs in Western Australia is low. Under current government policy potentially damaging activities, including commercial fishing, seismic surveys, and oil and gas drilling are permitted in protected areas.KEY WORDS: Marine protected areas; Dugongs; Western Australia; Indian Ocean; Conservation; Biodiversity  相似文献   
110.
The governments of British Columbia, Alberta, Saskatchewan, Manitoba, Northwest Territories, and Canada held joint consultations in 1980 to review the available information on acid rain from Western and Northern Canada. It was concluded that acid rain might become a problem in the future and, hence, a research, monitoring, and management strategy for acidic deposition was needed. An overview of the joint governments' management strategy, organization of research and monitoring programs, and accomplishments to date are discussed in this article.The authors are members of the Technical Committee for the Long Range Transport of Atmospheric Pollutants (LRTAP)/Acid Deposition in Western and Northern Canada, and represent Alberta and British Columbia, respectively.  相似文献   
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