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21.
This article examines the role of economic development agencies in strengthening the environmental performance of industry within rapidly industrialising East Asian economies. Three case-study examples are considered, namely, the role of the Industrial Development Board in reducing industrial pollution in Taiwan, pollution control in the palm oil industry in Malaysia, and the role of the Economic Development Board in influencing environmental performance of industry in Singapore. The concept of embedded autonomy is developed to consider the ways in which agencies of economic development can work with firms and industries while simultaneously remaining autonomous from these firms with respect to setting and enforcing performance standards. The three cases suggest that a form of policy integration that more directly integrates economic and environmental goals within agencies of economic development may be feasible, but only where there exists a strong autonomous government bureaucracy and where there is strong societal commitment to improving the environmental performance of industry.  相似文献   
22.
There is some concern in the environmental quality management (EQM) community that small and mid-sized companies do not have the technical, economic, and personnel resources or expertise to carry out significant programs of pollution prevention or waste reduction in the way that large corporations do. Thus, a very significant proportion of the economy may not be contributing to or benefiting from EQM approaches. This article begins to clarify what small and mid-sized companies that are committed to EQM can actually do and how this compares with the efforts of larger plants or plants operated as part of large multiplant corporations.  相似文献   
23.
The distribution and impacts of different nitrogen pollutants are inextricably linked. To understand the problem fully, the interactions between the different pollutants need to be taken into account. This is particularly important when it comes to abatement techniques, since measures to reduce emissions of one nitrogen pollutant can often lead to an increase in another. This project represents a step towards greater understanding of these issues by linking together new and existing nitrogen flux models into a larger framework. The modelling framework has been constructed and some of the nitrogen flows between fields, farms and the atmosphere have been modelled for a UK study area for typical farm management scenarios.  相似文献   
24.
Dissolved nitrous oxide (N2O), nitrate (NO3 -), and ammonium (NH4 +) concentrations in an agricultural field drain were intensively measured over the period of field nitrogen (N) fertilisation and for several weeks thereafter. Supersaturations of dissolved N2O were observed in field drain waters throughout the study. On entry to an open drainage ditch, concentrations of dissolved N2O rapidly decreased and a total N2O-N emission via this pathway of 13.2 g over the period of study (45 days) was calculated. This compared with a predicted emission of the order of 300 g, based on measured losses of NO3 - and NH4 + in the field drainage water, and the default IPCC emission factor of 0.01 kg N2O-N per kg Nentering rivers and estuaries. In contrast to widespread evidence of a clear relationship between the amount of N applied to agricultural land and subsequent direct N2O emission from the soil surface, the relationship between the amount of N2O in soil drainage waters and the amount of N applied was poor. We conclude that the complexity, both spatially and temporally, of the processes ultimately responsible for the amount of N2O in agricultural drainage waters make a straightforward relationship between N2O concentration and N application rate unlikely in all but the simplest of systems.  相似文献   
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ABSTRACT: This paper studies the effectiveness of alternative farm management strategies at improving water quality to meet Total Maximum Daily Loads (TMDLs) in agricultural watersheds. A spatial process model was calibrated using monthly flow, sediment, and phosphorus (P) losses (1994 to 1996) from Sand Creek watershed in south‐central Minnesota. Statistical evaluation of predicted and observed data gave r2 coefficients of 0.75, 0.69, and 0.49 for flow (average 4.1 m3/s), sediment load (average 0.44 ton/ha), and phosphorus load (average 0.97 kg/ha), respectively. The calibrated model was used to evaluate the effects of conservation tillage, conversion of crop land to pasture, and changes in phosphorus fertilizer application rate on pollutant loads. TMDLs were developed for sediment and P losses based on existing water quality standards and guidelines. Observed annual sediment and P losses exceeded these TMDLs by 59 percent and 83 percent, respectively. A combination of increased conservation tillage, reduced application rates of phosphorus fertilizer, and conversion of crop land to pasture could reduce sediment and phosphorus loads by 23 percent and 20 percent of existing loads, respectively. These reductions are much less than needed to meet TMDLs, suggesting that control of sediment using buffer strips and control of point sources of phosphorus are needed for the remaining reductions.  相似文献   
28.
Critical N loads for ombrotrophic bogs, which often contain rare and N-sensitive plants (especially those in lower plant groups: lichens, mosses and liverworts), are based on very few experimental data from measured, low background N deposition areas. Additionally the relative effects of reduced versus oxidised N are largely unknown. This paper describes an automated field exposure system (30 km S. of Edinburgh, Scotland) for treating ombrotrophic bog vegetation with fine droplets of oxidised N (NaNO3) and reduced N (NH4Cl). Whim Moss exists in an area of low ambient N deposition (ca. 8 kg N ha?1 y?1), the sources and quantification of which are described. The wet N treatment system is run continuously, and is controlled/activated by wind speed and rainfall to provide a unique simulation of “real worl” treatment patterns (no rain=no treatment). Simulated precipitation is supplied at ionic concentrations below 4 mM in rainwater collected on site. Treatments provide a replicated dose response to 16, 32 and 64 kg N ha?1 y?1 adjusted for ambient deposition (8 kg N ha?1 y?1). The 16 and 64 kg N ha?1 y?1 are duplicated with a P+K supplement. Baseline soil chemistry and foliar nutrient status was established for all 44 plots for Calluna vulgaris, Sphagnum capillifolium, Hypnum jutlandicum and Cladonia portentosa.  相似文献   
29.
Model estimates of NOy and NHx deposition across Britain for 1996 (5 km square resolution) were applied as explanatory variables to account for national-scale, fine-grained changes in plant species composition between 1990 and 1998. Plant species data were recorded from up to 27 fixed plots located within a stratified random sample of 596 1 km2. The response variable was a cover-weighted Ellenberg fertility score for each plot. Analyses were carried out separately for woodlands, semi-natural grasslands and heaths/bogs. Most of the variation in the botanical response variable occurred between plots within squares and so could not be explained by the model deposition data. NHx deposition estimates accounted for significant, but small components of between 1 km2 variation in the change in Ellenberg score in grasslands (5.6%) and heath/bogs (9.8%) but not woodlands. NOy deposition estimates were not significantly associated with vegetation change. Linear models provided the best fit and the slope of the relationship was lower for heath/bogs than grasslands. Further signal attribution at sub-kilometre square scales requires the development of fine-grained models of N deposition that can be generalised across regional sampling domains.  相似文献   
30.
Rapid land development is raising concern regarding the ability of urbanizing watersheds to sustain adequate base flow during periods of drought. Long term streamflow records from unregulated watersheds of the lower to middle Delaware River basin are examined to evaluate the impact of urbanization and imperviousness on base flow. Trends in annual base flow volumes, seven‐day low flows, and runoff ratios are determined for six urbanizing watersheds and four reference watersheds across three distinct physiographic regions. Hydrograph separation is used to determine annual base flow and stormflow volumes, and nonparametric trend tests are conducted on the resulting time series. Of the watersheds examined, the expected effects of declining base flow volumes and seven‐day low flows and increasing stormflows are seen in only one watershed that is approximately 20 percent impervious and has been subject to a net water export over the past 15 years. Both interbasin transfers and hydrologic mechanisms are invoked to explain these results. The results show that increases in impervious area may not result in measurable reductions in base flow at the watershed scale.  相似文献   
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