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921.
N. K. Woodfield J. W. S. Longhurst C. I. Beattie D. P. H. Laxen 《Water, Air, & Soil Pollution: Focus》2002,2(5-6):677-688
Across the United Kingdom, the majority of local authoritieshave now completed their first phase of local air qualityreview and assessment work, as required under the AirQuality Strategy for England, Scotland, Wales and NorthernIreland (DETR, 2000a). Emerging from this first phasework is an anticipated suite of over 110 Air QualityManagement Areas (AQMAs). These areas are identifiedlocations where one or more of the national air qualityobjectives are predicted to exceed by specific target dates,and their spatial extent and shape is emerging as highlyvariable. Local authorities are guided to use a variety ofscientific tools to underpin the scientific assessments, anda consideration of uncertainty in both the tools used andsubsequent delineation of AQMAs is likely to affect theemerging management areas significantly. With subsidiarity underpinning the process of local air qualitymanagement (LAQM), local decision-making is anticipated toinfluence the outcome of the LAQM process in its entirety,with the declaration of AQMAs necessitating the preparationand implementation of air quality action plans. UKexperience of the effective management of local air quality,through the designation of AQMAs, demonstrates a valuableframework for other European countries developing mechanismsto manage air quality locally. 相似文献
922.
P. Herzsprung K. Friese R. Frömmichen J. Göttlicher M. Koschorreck W. V. Tümpling Jr. K. Wendt-Potthoff 《Water, Air, & Soil Pollution: Focus》2002,2(3):123-140
In the past five years, enclosures have beeninstalled in an acidic mining lake in Lusatia to investigate insitu remediation processes. They were treated with straw, withstraw and Carbokalk, or with Carbokalk alone, where Carbokalkis a by-product of the sugar industry (solid precipitate ofnon-sugars after lime clarification of extracted sugar beetjuice). Sediment samples were taken as cores to get informationabout the behaviour of organic and inorganic components insediment pore-water with depth. Vertical distributions of pH,soluble reactive phosphate, nitrate, ammonium, silica,aluminium, iron, manganese, calcium, magnesium, sodium,potassium, sulphate, and DOC were measured. The resultingprofiles, each consisting of 15 data points at differentdepths, were compared by cluster analysis. The similarities ofsediment cores from different treated enclosures relating toprofiles of chemical components were discussed. Increasedconcentrations of potassium and sulphate were found in pore-water after substrate treatment. The data imply dissolution ofpotassium iron sulphate hydroxide minerals (jarosite) after anincrease of pH caused by dissolution of lime and by sulphatereducing processes which were stimulated by organic substrateaddition. 相似文献
923.
Trends in the Water Chemistry of High Altitude Lakes in Europe 总被引:2,自引:0,他引:2
Mosello R. Lami A. Marchetto A. Rogora M. Wathne B. Lien L. Catalan J. Camarero L. Ventura M. Psenner R. Koinig K. Thies H. Sommaruga-Wögrath S. Nickus U. Tait D. Thaler B. Barbieri A. Harriman R. 《Water, Air, & Soil Pollution: Focus》2002,2(2):75-89
Here we present the chemical trends of seven high altitude lakes, analysed within the AL:PE and MOLAR Projects of the EU (1999) and selected on the basis of the availability of complete and reliable data for the period 1984–1999. The lakes are representative of the Scandinavian Alps, the Cairngorm Mountains in Scotland, the Alps and the Pyrenees. Significant trends were identified for some indicators of acidification, for instance pH and alkalinity, but not all lakes reacted similarly to decreasing depositions of sulphate and base cations. Differences in lake response are discussed in relation to recent variations of atmospheric deposition chemistry and associated changes in climatic conditions. Beside individual variations of the studied lakes, depending, among other things, on altitude and morphology, catchment characteristics and climate trends play a major role for the reaction of high altitude lakes on changes in atmospheric depositions. 相似文献
924.
K. K. Chatterjee 《Resources Policy》2002,28(3-4)
In India, the mineral resource inventory and the production of a large number of important minerals have registered significant increases during the last few decades. Yet the country continues to be a net importer of many high value and scarce minerals and metals, like gold, diamond, and several base metals. Exploration and development of the resources of these minerals are technology- and capital-intensive. To bring technology and capital through foreign direct investment (FDI) into the Indian mineral sector, it is imperative to lay stress on: accurate resource estimation and categorization, as well as realistic projection of the true values; rationalization of legislative measures based on R&D studies and reorganization of the implementation machinery; conducive tax structure; notification of acts and rules applicable to offshore mineral resources; time-frames for granting licences and leases; encouragement to labor productivity by rationalizing labor laws; reforms in the monetary system to increase market competitiveness of Indian minerals; and judicial reforms. FDI in the Indian mineral sector is important to firm up the knowledge-base of mineral resources and their optimum exploitation. 相似文献
925.
R. M. Patel S. O. Prasher P. K. God R. Bassi 《Journal of the American Water Resources Association》2002,38(1):91-100
ABSTRACT: This study explores the applicability of Artificial Neural Networks (ANNs) for predicting salt build‐up in the crop root zone. ANN models were developed with salinity data from field lysimeters subirrigated with brackish water. Different ANN architectures were explored by varying the number of processing elements (PEs) (from 1 to 30) for replicate data from a 0.4 m water table, 0.8 m water table, and both 0.4 and 0.8 m water table lysimeters. Different ANN models were developed by using individual replicate treatment values as well as the mean value for each treatment. For replicate data, the models with twenty, seven, and six PEs were found to be the best for the water tables at 0.4 m, 0.8 m and both water tables combined, respectively. The correlation coefficients between observed salinity and ANN predicted salinity of the test data with these models were 0.89, 0.91, and 0.89, respectively. The performance of the ANNs developed using mean salinity values of the replicates was found to be similar to those with replicate data. Not only was there agreement between observed and ANN predicted salinity values, the results clearly indicated the potential use of ANN models for predicting salt build‐up in soil profile at a specific site. 相似文献
926.
927.
928.
K. A. Edwards 《Natural resources forum》1993,17(1):59-64
This paper for the most part constitutes the address which was made to the Consortium for International Development at their recent Presidential Symposium at Colorado State University on 30 July 1992. It raises some of the global issues in water resources development and management which are likely to confront the international community in the 1990s and beyond. The issues pose the challenge to institutions involved in the water resources field in both developed and developing countries. 相似文献
929.
Inconsistent findings have been reported in the few studies investigating the relationship between the perceived value of pay and incentive performance. One hundred and seventy-eight female incentive employees with a nine-week, non-judgmental performance measure responded to a developed valence of pay scale. This measure used items assessing the perceived ability of pay to address employee needs. Three factor-scales were found within these items. Support for the hypothesized positive relationship between pay valence and incentive performance was found, dependent on which of the three scales was used. These findings provide initial insight into the means by which pay, with its ability to address different needs, might provide differential employee motivation and performance levels. This study and future research issues are discussed. 相似文献
930.