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141.
We explore the consequences of modeling the demand for environmental quality improvements as a fully integrated part of a general equilibrium demand system in an applied general equilibrium (or CGE) analysis. Demand for non-market goods depends on a full range of relative prices as well as environmental outcomes. We simulate the effects of reducing two air pollutants to improve human health and three ecosystem services provided to households. The ecosystem services make non-separable contributions to household utility. We find that willingness to pay measures of use-based ecosystem services are impacted by changes in demand for complementary market goods. Demand for these goods shifts due to pollution reductions that enhance ecosystem services. Partial equilibrium estimates of these use values can be measured with substantial error if they fail to account for the general equilibrium adjustments caused by pollution. Over 300 calibrations of the model identify the model features important to these errors. We find that effects on ecosystem services associated with non-use values have important implications for the feedback effects on use related measures of economic tradeoffs. This is due to how our model integrates market and non-market effects, reflecting the non-market services importance to general equilibrium market outcomes.  相似文献   
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This paper argues that the delay required for resolution of uncertainty in the technical information for policy making depends on how the relevant policy issues are posed. The relationship between CO2 and global mean temperature is used to illustrate the argument in terms of the testing of specific hypotheses.  相似文献   
147.
The wood cockroach Cryptocercus punctulatus nests as family units inside decayed wood, a substrate known for its high microbial load. We tested the hypothesis that defecation within their nests, a common occurrence in this species, reduces the probability of fungal development. Conidia of the entomopathogenic fungus, Metarhizium anisopliae, were incubated with crushed feces and subsequently plated on potato dextrose agar. Relative to controls, the viability of fungal conidia was significantly reduced following incubation with feces and was negatively correlated with incubation time. Although the cockroach's hindgut contained abundant β-1,3-glucanase activity, its feces had no detectable enzymatic function. Hence, these enzymes are unlikely the source of the fungistasis. Instead, the antifungal compound(s) of the feces involved heat-sensitive factor(s) of potential microbial origin. When feces were boiled or when they were subjected to ultraviolet radiation and subsequently incubated with conidia, viability was “rescued” and germination rates were similar to those of controls. Filtration experiments indicate that the fungistatic activity of feces results from chemical interference. Because Cryptocercidae cockroaches have been considered appropriate models to make inferences about the factors fostering the evolution of termite sociality, we suggest that nesting in microbe-rich environments likely selected for the coupling of intranest defecation and feces fungistasis in the common ancestor of wood cockroaches and termites. This might in turn have served as a preadaptation that prevented mycosis as these phylogenetically related taxa diverged and evolved respectively into subsocial and eusocial organizations.  相似文献   
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During the summers of 2002 and 2004, in-stream integrated flow and concentration measurements for the total dissolved solids in the Cheyenne River, South Dakota, USA was conducted in order to compare the obtained actual field measurements with the predictions values made by the Bureau of Reclamation in the Environmental Impact Statement. In comparison to the actual field measurements conducted in this study, The Bureau of Reclamation extension of a small database used in the analysis for the impact of operations at the Angostura Unit over the past 50 years and into the future to predict the annual total dissolved solid loadings doesn't represent the actual loading values and various conditions in the study area. Additional integrated flow and concentration sampling is required to characterize the impact of the current Angostura Dam operations and Angostura Irrigation District return flows on the Cheyenne River in different seasons of the year.  相似文献   
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