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The Resource Management Act 1991 provides a new mandate for effectsbased planning with its goal of sustainable management. Regional, city and district councils are responsible for administering the Act, including preparation of regional policy statements, regional and district plans. The paper reports on a collaborative research programme,funded by the New Zealand Foundation for Research, Science and Technology. The three-year programme has two objectives: (1) to determine the quality of policy statements and plans; and (2) to identify the extent and means by which councils co-ordinate policy statements and plans. Preliminary findings on implementation of the Act are presented.  相似文献   
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Laboratory bleaching experiments were performed to investigate PCDD/PCDF formation mechanisms. The results indicated that there were two (or more) mechanisms; direct chlorination of DBD/DBF and formation from precursors which are not extractable. In general, PCDDs/PCDFs are formed in the C stage but some minor isomers were found to be formed in the E stage.  相似文献   
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Until recently, relatively little attention has been paid to the problem of enforcing mitigation measures identified in environmental impact assessment. Present or proposed enforcement systems in the USA, New South Wales, South Australia, and Western Australia are described and discussed. Although the best enforcement system would depend on the local social, political, and legal systems, five universally desirable features are identified. First, a comprehensive coordinated monitoring and reassessment system is needed. Second, the agencies concerned must have adequate resources to do the work and incentives to carry it out well. Third, there must be the necessary legal powers. Fourth, provision must be made for changing the conditions based on experience. And fifth, the system should be equally effective against private companies and public authorities.  相似文献   
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Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.  相似文献   
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Changes in nitrification rates of an acid grassland soil with and without air drying have been monitored over 9 days, after first flushing native nitrate from the soils with deionised water. The results confirmed that full re-establishment of nitrification after air drying takes several days, supporting the hypothesis that any immediate first flush of nitrate from air-dried soils originates from cell lysis or flushing of ‘stored’ nitrate. Ammonium spiking confirmed that nitrification was not ammonium substrate limited. It was also found that ammonium accumulates in the soil during the drying process, providing a substrate pool once the population of nitrifiers has re-established. Over the first week of incubation, nitrate immobilisation was less conspicuous in the soil that had been rewetted after air drying compared with the incubated field moist soil.  相似文献   
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Samples have been collected from major horizons of 34 podzol profiles distributed throughout Scotland, all developed from granite or granitic tills and under Calluna moorland. the pH in water and calcium chloride pastes, exchangeable cations and cation exchange capacity, and extractable aluminium of the soils collected have been measured, and the results studied in relation to reported atmospheric deposition of H+, non-marine sulphur and nitrate. for all horizons, significant positive correlations were found between soil pH and rainfall mean pH, as might be expected when the critical load of H+ deposition is exceeded. Acidifying pollutant deposition also apparently increased soil extractable aluminium concentrations in the B and C horizons. However, exchangeable base cation concentrations tended to increase, rather than decrease, with increasing precipitation acidity. This effect was attributed to increases in biogeochemical cycling of base cations, increases in leaching inputs of base cations from overlying A/E horizon soils, and increases in the inputs of base cations leached from upslope. the results suggest that the simple steady state mass approach to the quantification of critical loads, as often applied, may be an oversimplification.  相似文献   
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