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441.
There is a growing recognition that knowledge of indigenous communities, based on accumulated observations and experience over time, is significant for sustainable environmental management in collaboration with modern scientific knowledge. A number of innovative policy initiatives are currently being implemented in New Zealand to enable indigenous Maori tribes and sub-tribes to rehabilitate and manage their local fisheries in accordance with customary values and practices. These policies are an important milestone from an historical perspective as they are meant to recognise and empower the role of Maori as Treaty partners. The fisheries management regime in New Zealand now provides for Maori representation at the local level within a co-management framework that enables local Maori communities to exercise their customary rights. These institutional arrangements have been crafted to facilitate Maori input, based on customary values and practices, to complement modern Western management practices for sustainable harvesting of marine resources. Nevertheless, the degree to which these initiatives constitute an adequate response to Maori Treaty aspirations is debatable. A major constraint in this respect is that the government is compelled to recognise the needs of other, economically and politically more dominant, non-Maori user-groups in allocating and managing access to fishery resources and the marine environment.  相似文献   
442.
ABSTRACT: Most watershed water quality simulation models require the user to specify pollutant buildup and washoff rate parameters for pollutants, by land use. Buildup and washoff rates are difficult to measure directly, and only limited guidance and few observed data are available from the literature. Many studies, however, report storm event mean concentrations (EMCs). These EMCs must arise as a result of the buildup and washoff processes, but typically represent the net contribution from a variety of pervious and impervious surfaces. This paper explores the relationship between EMCs and buildup/washoff parameters. An assumption of the mathematical form of the buildup/washoff relationship gives an algebraic expression for the EMC consistent with model assumptions. This yields techniques to separate observed EMCs into contributions from different land uses and from pervious and impervious surfaces. Given this relationship, numerical optimization may be used to estimate site specific values of buildup and washoff parameters from observed storm EMCs for use in modeling. Use of this approach helps ensure that model parameters are consistent with observed data, providing a rational starting point for final model calibration. Several site examples demonstrate use of the method.  相似文献   
443.
Open-cast lignite mining in the Lusatian mining district resulted in rehabilitated mine soils containing up to four organic matter types: (1) recent plant litter, (2) lignite deposited by mining activity, (3) carbonaceous ash particles deposited during amelioration of the lignite-containing parent substrate and (4) airborne carbonaceous particles deposited during contamination. The influence of lignite-derived carbon types on the organic matter development and their role in the soil carbon cycle was unknown. This paper presents the findings obtained during a six year project concerning the impact of lignite on soil organic matter composition and the biogeochemical functioning of the ecosystem. The organic matter development after rehabilitation was followed in a chronosequence of rehabilitated mine soils afforested in 1966, 1981 and 1987. A differentiation of the organic matter types and an evaluation of their role within the ecosystem was achieved by the use of 14C activity measurements, 13C CPMAS NMR spectroscopy and wet chemical analysis of plant litter compounds. The results showed that the amount and degree of decomposition of the recent organic matter derived from plant material of the 30 year old mine soil was similar to natural uncontaminated forest soil which suggests complete rehabilitation of the ecosystem. The decomposition and humification processes were not influenced by the presence of lignite. On the other hand it was shown that lignite, which was thought to be recalcitrant because of its chemical structure, was part of the carbon cycle in these soils. This demonstrates the need to elucidate further the stabilisation mechanisms of organic matter in soils.  相似文献   
444.
At the district heating plant of Kalmar, Sweden an on-line unit for production of granulated wood ash for nutrient recycling on forest soils is being applied. Currently, the granules are dried by hot air from an oil-fired burner. The objective of this work was to investigate how drying by flue gas affects the hardening of granules, or impacts their chemical composition and properties. Ninety-six granule samples were treated by flue gas from natural gas combustion in a laboratory pilot scale flue gas generator. CO2, CO, O2, C3H8 and NO concentrations were varied during the experiment. Additionally, some samples were treated by flue gas from combustion of sawdust at the heating plant in Kalmar. Drying by flue gases did not affect the chemical composition of granules, but minor effects were seen in their mineralogy. The carbonate content was slightly higher in granules treated with flue gas from natural gas combustion compared to the granules dried by hot air only, when measured by wet chemical methods. Results from XRD analysis imply that the calcite content is higher and the portlandite and arcanite content slightly less in granules treated with flue gas from sawdust combustion compared to the granules dried by hot air only. The results from this investigation showed no negative effects on ash granule composition or physical structure by the use of a flue as a drying medium.  相似文献   
445.
The creation of a cloned sheep from mammary tissue has raisedmajor social concern, and much talk about major ethical issuesoccasioned by this technology. It is necessary to separategenuine from spurious ethical issues here, a task made failureto initiate ethical discussion and explanation of new technologyas well as by fear reactions in society. As in geneticengineering of animals, issues about cloning fall into threecategories – suggestions that the technology is inherently wrong,risk emerging from the technology and harm to the creatureengendered. The issues regarding the cloning of humans can beanalyzed using the same categories.  相似文献   
446.
A pedagogic problem in forestry and landscape management is to visualize future landscape effects of forest growth and current management activities in the forest. This paper presents a method for forecasting digital image projections of forest landscape dynamics. Static nonlinear regression functions estimate the digital numbers in a Landsat Thematic Mapper image. Regressors used are forest stand variables. By estimating the future forest stand data, based on intermediate treatment and growth, future satellite digital images are created. In a case study example, the future landscape of a forest block in the province of Västernorrland, Sweden, is projected to demonstrate the application of this visualization technique.  相似文献   
447.
The California Environmental Quality Act (CEQA) has evolved from a mini-NEPA, first enacted in 1970, into a procedural act that affects the approval process of all large developments in California. In 1990, California local governments produced over 1600 environmental impact reports and 30,000 initial studies under CEQA. Because of its widespread use, CEQA has periodically drawn the attention of the state legislature, most recently in 1993, when over 60 CEQA reform bills were introduced. This paper describes the CEQA process and evaluates its success at meeting its explicit and implicit goals. The research includes a statewide survey of CEQA practice, sent to the planning departments of all 513 local governments in California in 1991. Survey respondents agreed that CEQA helps in evaluating environmental impacts, reducing impacts, informing the public, and coordinating public agency review. It is effective in reducing the environmental impacts of individual projects, but is not as effective in improving environmental quality on an areawide scale. This research concludes that CEQA has led to positive outcomes and is not as deeply flawed as many of its critics claim. Still, CEQA as currently designed may not be the optimal vehicle for ensuring environmental quality.  相似文献   
448.
The project on Biodiversity Uncertainties and Research Needs (BURN) ensures the advancement of usable knowledge on biodiversity by obtaining input from decision makers on their priority information needs about biodiversity and then using this input to engage leading scientists in designing policy-relevant research. Decision makers articulated concerns related to four issues: significance of biodiversity; status and trends of biodiversity; management for biodiversity; and the linkage of social, cultural, economic, legal, and biological objectives. Leading natural and social scientists then identified the research required to address the decision makers' needs and determined the probability of success. The diverse group of experts reached consensus on several fundamental issues, helping to clarify the role of biodiversity in land and resource management. The BURN participants identified several features that should be incorporated into policy-relevant research plans and management strategies for biodiversity. Research and assessment efforts should be: multidisciplinary and integrative, participatory with stakeholder involvement, hierarchical (multiple scales), and problem- and region-specific. The activities should be focused regionally within a global perspective. Meta-analysis of existing data is needed on all fronts to assess the state of the science. More specifically, the scientists recommended six priority research areas that should be pursued to address the information needs articulated by decision makers: (1) characterization of biodiversity, (2) environmental valuation, (3) management for sustainability—for humans and the environment (adaptive management), (4) information management strategies, (5) governance and stewardship issues, and (6) communication and outreach. Broad recommendations were developed for each research area to provide direction for research planning and resource management strategies. The results will directly benefit those groups that require biodiversity research to address their needs—whether to develop policy, manage natural resources, or make other decisions affecting biodiversity.  相似文献   
449.
In 1995 the authors spent a considerable amount of time conducting audits and audit training classes all over the world. In rolling out Colgate-Palmolive's reengineered environmental audit program, they coupled a two-day training program with a three-day audit. Whether in Asia-Pacific, South America, Europe, or the United States, auditors, especially those newly trained, always seemed to fall into the same traps time and again. In order to facilitate the learning process, the authors prepared a list of 20 tips to use at the beginning and end of all training programs and audits. In this article, the authors share the 20 “golden rules” to help all auditors improve the quality of their audits.  相似文献   
450.
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