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41.
Use of environmental valuation and benefits transfer in a recent legal ruling in the UK between Thames Water Utilities and the Environment Agency over water abstraction costs appeared to set an unfortunate precedent. In the first attempt to fulfil its statutory duties, the Agency was thwarted in its use and interpretation of non-market valuation techniques, in particular, the vexed issue of how to aggregate the results of valuation studies in original sites or those to where values might be transferred. The ruling has broader implications for water pricing and resource development by the industry. Far from being a blow for either cost-benefit analysis or environmental valuation, the decision highlights some of the research imperatives for the derivation of non-market values by economists and their translation for use in government decisions.  相似文献   
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Generally speaking, there is a greater amount of quantitative data available to measure and model the cumulative environmental or economic impacts of mining than the social impacts. In part, this is because social impacts are often inherently more difficult to quantify, but historically there have also been fewer regulatory drivers for companies or state agencies to invest in collecting such data. Regulators in some jurisdictions are now starting to require resource companies to report on aspects of their social performance, but companies and regulators are still struggling to identify appropriate metrics, particularly in regards to cumulative impacts. This paper describes an innovative quantitative approach to tracking how communities experience and respond to increased mining activity, using data from the complaints registers maintained by mines located in the Upper Hunter Valley in New South Wales, Australia. In this study, complaints lodged with five separate mines adjacent to the township of Muswellbrook over several years were aggregated and trends analysed. The aggregated set showed that complaint frequency increased with the increase in mining activity but then decreased as individual complaints were addressed. However, when complaints from near-neighbours were removed, it emerged that the proportion of complaints that came from the town itself steadily increased over time. Further analysis indicated that this increase was closely associated with the amount of mine-disturbed land that could be seen from the town over time, as measured using a combination of remotely sensed data and a digital elevation model. This is persuasive evidence of a cumulative social impact that is more than just the sum of the local impacts of individual mines.  相似文献   
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The naturally occurring radionuclide 226Ra (t1/2 = 1600 years) was used as a tracer to determine ground water input to Point Judith, Potter, Green Hill and Ninigret ponds in southern Rhode Island. Measurements of 226Ra activity were made in samples collected from salt ponds, pore waters, sediments, and local ground water wells during June-August, 1997. These results were combined with a simple box model to derive ground water input fluxes of 0.1-0.3 cm3 cm-2 d-1 (2-5 x 10(7) L d-1), which are comparable to previous estimates of ground water input to these ponds.  相似文献   
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Fouling communities were transferred between Wollongong Harbour (Australia), a relatively unpolluted area, and nearby Port Kembla Harbour which is affected by pollution from nearby heavy industries. Those that had been transferred from Wollongong Harbour were similar in structure after two months to those that had developed entirely in Port Kembla Harbour. Conversely, the communities transferred from Port Kembla Harbour had a similar structure to those that had developed only in Wollongong Harbour. Many of the species transferred from Wollongong Harbour were thought to have been killed by periodic high concentrations of pollutants or overgrown by more competitive species. Those few that survived the polluted conditions were mainly bryozoans and serpulids. Surprisingly, many supposedly pollution-tolerant species transferred from Port Kembla Harbour did not survive in Wollongong Harbour. It is suggested that this was because these animals could not tolerate the lower nutrient conditions in the latter area. Space once occupied by these species was quickly colonised by species found only in Wollongong Harbour. These results have important implications for the functioning of these communities.  相似文献   
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Bacterial diversity in the microbial communities of posterior gut sections of three temperate marine herbivorous fish species from New Zealand was characterised using Amplified Ribosomal DNA Restriction Analysis, and 16S rRNA gene amplification and sequencing methods. The fish were collected in 1999–2000 in the Hauraki Gulf, New Zealand (35°54’–36°24’S, 174°48’–175°25’E). The gastrointestinal bacterial communities of Kyphosus sydneyanus (Günther, 1886) (F. Kyphosidae), Odax pullus (Forster in Bloch and Schneider, 1801) (F. Labridae) and Aplodactylus arctidens Richardson, 1839 (F. Aplodactylidae) were dominated by five clades of bacteria, four of which belong to recognized clostridial clusters. The clone libraries of K. sydneyanus and O. pullus contained sequences from most of these clades, but were dominated by members of clostridial clusters XI and XIVa, respectively. The clone library of A. arctidens was dominated by members of clostridial cluster XIVb and an unassigned cluster containing Eubacterium desmolans and Papillibacter cinnaminovorans. The finding that strains of Firmicutes dominated the gastrointestinal microbial communities of all three fish species is consistent with the results of similar studies on terrestrial vertebrate herbivores. This work thus contributes to the view that gastrointestinal symbionts in some marine herbivorous fishes may play a similar role to those in terrestrial vertebrate herbivores studied to date.  相似文献   
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Many long-lived radionuclides are present in groundwater at the Nevada Test Site (NTS) as a result of 828 underground nuclear weapons tests conducted between 1951 and 1992. In conjunction with a comprehensive geochemical review of radionuclides ((3)H, (14)C, (36)Cl, (99)Tc and (129)I) that are presumably mobile in the subsurface, we synthesized a body of radionuclide activity data measured from groundwater samples collected at 18 monitoring wells, to qualitatively assess their migration at the NTS over distances of hundreds of meters and over timescales of decades. Tritium and (36)Cl showed little evidence of retardation, while the transport of (14)C may have been retarded by its isotopic exchange with carbonate minerals in the aquifer. Observed local reducing conditions (either natural or test-induced) will impact the mobility of certain redox-sensitive radionuclides (especially (99)Tc) that were otherwise soluble and readily transported under oxidizing conditions. Conversely, strongly oxidizing conditions may impact the mobility of (129)I which is mobile under reducing conditions. The effect of iodine speciation on its transport deserves further attention. Indication of delayed transport of some "mobile" radionuclides (especially (99)Tc) in the groundwater at the NTS suggested the importance of redox conditions of the natural system in controlling the fate and transport of radionuclides, which has implications in the enhanced performance of the potential Yucca Mountain repository, located adjacent to the NTS, to store high-level nuclear wastes as well as management of radionuclide contamination in legacy nuclear operations facilities.  相似文献   
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• A model-free sewer-WWTP integrated control was proposed. • A dynamic discrete control based on the water level was developed. • The approach could improve the sewer operation against flow fluctuation. • The approach could increase transport capacity and enhance pump efficiency. This study aims to propose a multi-point integrated real-time control method based on discrete dynamic water level variations, which can be realized only based on the programmable logic controller (PLC) system without using a complex mathematical model. A discretized water level control model was developed to conduct the real-time control based on data-automation. It combines the upstream pumping stations and the downstream influent pumping systems of wastewater treatment plant (WWTP). The discretized water level control method can regulate dynamic wastewater pumping flow of pumps following the dynamic water level variation in the sewer system. This control method has been successfully applied in practical integrated operations of sewer-WWTP following the sensitive flow disturbances of the sewer system. The operational results showed that the control method could provide a more stabilized regulate pumping flow for treatment process; it can also reduce the occurrence risk of combined sewer overflow (CSO) during heavy rainfall events by increasing transport capacity of pumping station and influent flow in WWTP, which takes full advantage of storage space in the sewer system.  相似文献   
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Environmental Management - Although the link between agriculture and diffuse water pollution has been understood for decades, there is still a need to implement effective measures to address this...  相似文献   
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