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91.
92.
This paper extends previous research assessing the effects of environmental pollution on property values, and the specific issue of information disclosure requirements on future real estate transactions. Given that various information disclosure requirements were imposed in most US states during the 1990s, it is important to begin to understand their anticipated effects. Using a case of soil contamination in Corpus Christi, TX, USA, this paper applies the contingent valuation method using telephone survey data to investigate the effect of a split-sample information disclosure treatment concerning soil contamination on the willingness to pay of potential home buyers. The authors apply a mixture modelling approach to better explain the effect of the information disclosure requirement.  相似文献   
93.
Integrated Measures of Anthropogenic Stress in the U.S. Great Lakes Basin   总被引:1,自引:0,他引:1  
Integrated, quantitative expressions of anthropogenic stress over large geographic regions can be valuable tools in environmental research and management. Despite the fundamental appeal of a regional approach, development of regional stress measures remains one of the most important current challenges in environmental science. Using publicly available, pre-existing spatial datasets, we developed a geographic information system database of 86 variables related to five classes of anthropogenic stress in the U.S. Great Lakes basin: agriculture, atmospheric deposition, human population, land cover, and point source pollution. The original variables were quantified by a variety of data types over a broad range of spatial and classification resolutions. We summarized the original data for 762 watershed-based units that comprise the U.S. portion of the basin and then used principal components analysis to develop overall stress measures within each stress category. We developed a cumulative stress index by combining the first principal component from each of the five stress categories. Maps of the stress measures illustrate strong spatial patterns across the basin, with the greatest amount of stress occurring on the western shore of Lake Michigan, southwest Lake Erie, and southeastern Lake Ontario. We found strong relationships between the stress measures and characteristics of bird communities, fish communities, and water chemistry measurements from the coastal region. The stress measures are taken to represent the major threats to coastal ecosystems in the U.S. Great Lakes. Such regional-scale efforts are critical for understanding relationships between human disturbance and ecosystem response, and can be used to guide environmental decision-making at both regional and local scales.  相似文献   
94.
The sabellid, Terebrasabella heterouncinata, is a small (<5 mm) intratubular brooder that lives in burrows within the hosts shell matrix. It is a semi-continuous breeder and despite producing small numbers of large eggs, infestation by this animal has reached epidemic proportions on local abalone farms. The present study compared the morphometrics and reproductive characteristics of worms from farmed and wild abalone, in the Walker Bay area of the south Western Cape Province of South Africa, to gain insights into why this animal has become so successful under aquaculture conditions. The farms designated farm A and farm B each had one on-farm site, and two wild sites, while farm C had two on-farm sites and two wild sites. The wild sites were natural abalone habitats located within 2.5 km of the farms. Our results conclusively showed that environmental conditions prevalent on the farms enhanced the reproductive success of these worms relative to that observed in its natural environment. At farms B and C, worms occurred in significantly higher densities at the on-farm sites than in the corresponding wild samples, but at farm A, density was equally low at the three sites. At all three farms, a greater proportion of the population was reproductively active in the on-farm samples than in the wild samples. Worms on farmed abalone had a higher instantaneous fecundity, brooded more clutches simultaneously and were larger than their conspecifics from the wild. There was a positive correlation between adult size and brood size and the number of clutches brooded simultaneously. Within the three on-farm sites there was a negative correlation between egg volume and brood size, indicating a trade-off between these traits. However, such a trade-off was not apparent between sites, with brood size being higher at the on-farm sites than at the wild sites, irrespective of egg size. This suggests that the stable nutrient-enriched environment on the farm led to an increase in fecundity without compromising the size (and implicitly the quality) of the eggs. Worm density did not have a significant effect on body size or any other reproductive traits at most sites, and the density of T. heterouncinata was unaffected by the density of other shell-infesting polychaetes. The results suggest that the farm environment has selected for larger, more fecund worms that breed rapidly with high recruitment success as a consequence of abundant nutrients, high host density, habitat stability and a possible lack of predation and interspecific competition.Communicated by J.P. Thorpe, Port Erin  相似文献   
95.
96.
Emergency managers who work on floods and other weather‐related hazards constitute critical frontline responders to disasters. Yet, while these professionals operate in a realm rife with uncertainty related to forecasts and other unknowns, the influence of uncertainty on their decision‐making is poorly understood. Consequently, a national‐level survey of county emergency managers in the United States was administered to examine how they interpret forecast information, using hypothetical climate, flood, and weather scenarios to simulate their responses to uncertain information. The study revealed that even emergency managers with substantial experience take decision shortcuts and make biased choices, just as do members of the general population. Their choices vary depending on such features as the format in which probabilistic forecasts are presented and whether outcomes are represented as gains or losses. In sum, forecast producers who consider these decision processes when developing and communicating forecasts could help to improve flood preparation and potentially reduce disaster losses.  相似文献   
97.
98.
Decision parameters prevailing in the market lead to a slim expression of interest of foreign investors for Clean Development Mechanism (CDM) projects in a bi- or multilateral design in Yemen. The Designated National Authority Secretariat in Yemen experiences the preference of Annex I entities of merely buying Certified Emission Reductions rather than investing in projects. Yemen's ability, like many least developed countries, to carry out unilateral CDM projects is moderate. Domestic project developers perceive difficulties in procuring underlying finance as key barrier in materializing CDM project activities in a unilateral design. The country remains trapped in a “catch 22 situation”. International assistance through low interest loans and capacity building for domestic financial institutions tailored to CDM project activities may trigger the market. Aggravation can be assisted by amending the policies of Annex I countries, in consequence to allocate a substantial share of their procurement activities to Certified Emission Reductions from least developed countries. Acquisition programmes may give preference to projects from host countries not traditionally represented in the pool of attractive CDM destinations.  相似文献   
99.
Remediation processes for recovery and reuse of chromated-copper-arsenate- (CCA) treated wood are not gaining wide acceptance because they are more expensive than landfill disposal. One reason is the high cost of the nutrient medium used to culture the metal-tolerant bacterium, Bacillus licheniformis, which removes 70-100% of the copper, chromium, and arsenic from CCA-treated southern yellow pine (CCA-SYP) in a two-step process involving oxalic acid extraction and bacterial culture. To reduce this cost, the nutrient concentration in the culture medium and the ratio of wood to nutrient medium were optimized. Maximum metal removal occurred when B. licheniformis was cultured in 1.0% nutrient medium and at a wood to nutrient medium ratio of 1:10. Also, malted barley, an abundant by-product of brewing, was evaluated as an alternative nutrient medium. Tests were done to determine absorption of metals by barley, and the results indicate that the barley acted as a biosorbent, removing heavy metals from the liquid culture after their release from CCA to SYP. For comparison, tests were also performed with no nutrient medium. Following bacterial remediation, 17% copper and 15% arsenic were removed from an aqueous slurry of CCA-SYP (no medium). When oxalic acid extraction preceded the aqueous bacterial culture, 21% copper, 54% chromium, and 63% arsenic were removed. The two-step process (oxalic acid extraction and bacterial culture with nutrient medium) appears to be an effective, yet costly, way to remove metals.  相似文献   
100.
This paper analyzes the investment/environment overlap using a two stage model of two jurisdictions. Capital exports are modeled as choice variables for capital owners who weigh income considerations against the effects of capital exports on the quality of their local environments and on environmental policy. This framework reveals that capital owners have an incentive to cross-haul polluting factors across jurisdictions when direct controls are used to regulate emissions and that this cross-hauling induces policymakers to ratchet up environmental policies in both locations. The importance of instrument type and commitment on environmental policy is also analyzed.  相似文献   
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