OPTIMAL ECONOMIC MANAGEMENT OF GROUNDWATER QUANTITY AND QUALITY: AN INTEGRATED APPROACH

A dynamic model is developed that jointly optimizes over groundwater quality and quantity for extractive municipal and non-extractive agricultural users. The model is applied to an aquifer in southern Ontario to analyze several policy scenarios, demonstrating that interactions between externalities can partially offset one another.Environmental Economics and Policy, Resource /Energy Economics and Policy,

Scanning tunneling microscopy studies of monolayer templates: alkylthioethers and alkylethers

Scanning tunneling microscopy has been used to determine the molecular ordering in stable, ordered monolayers formed from long-chain normal and substituted alkanes in solution on highly oriented pyrolytic graphite surfaces. Monolayers were initially formed using an overlying solution of either a symmetrical dialkylthioether or a symmetrical dialkylether. Initially pure thioether solutions were then changed to nearly pure solutions of the identical chain-length ether, and vice versa. The direct application of a pure solution of long-chain symmetrical ethers onto graphite produced a lamellate monolayer within which the individual molecular axes were oriented at an angle of ~65° to the lamellar axes. In contrast, a pure solution of long-chain symmetrical thioethers on graphite produced a monolayer within which the molecular axes were oriented perpendicular to the lamellar axes. When ethers were gradually added to solutions overlying pure thioether monolayers, the ethers substituted into the existing monolayer structure. Thus, the ether molecules could be forced to orient in the perpendicular thioether-like manner through the use of a thioether template monolayer. Continued addition of ethers to the solution ultimately produced a nearly pure ether monolayer that retained the orientation of the thioether monolayer template. However, a monolayer of thioether molecules formed by gradual substitution into an ether monolayer did not retain the 65° orientation typical of dialkylethers, but exhibited the 90° orientation typical of dialkylthioether monolayers. The thioethers and ethers were easily distinguished in images of mixed monolayers, allowing both an analysis of the distribution of the molecules within the mixed monolayers and a comparison of the monolayer compositions with those of the overlying solutions. Substitution of molecules into the template monolayer did not proceed randomly; instead, a molecule within a monolayer was more likely to be replaced by a molecule in the overlying solution if it was located next to a molecule that had already been replaced

An Experimental Test of Buffer Utility as a Technique for Managing Pool-Breeding Amphibians

Vegetated buffers are used extensively to manage wetland-dependent wildlife. Despite widespread application, buffer utility has not been experimentally validated for most species. To address this gap, we conducted a six-year, landscape-scale experiment, testing how buffers of different widths affect the demographic structure of two amphibian species at 11 ephemeral pools in a working forest of the northeastern U.S. We randomly assigned each pool to one of three treatments (i.e., reference, 100m buffer, 30m buffer) and clearcut to create buffers. We captured all spotted salamanders and wood frogs breeding in each pool and examined the impacts of treatment and hydroperiod on breeding-population abundance, sex ratio, and recapture rate. The negative effects of clearcutting tended to increase as forest-buffer width decreased and be strongest for salamanders and when other stressors were present (e.g., at short-hydroperiod pools). Recapture rates were reduced in the 30m, but not 100m, treatment. Throughout the experiment for frogs, and during the first year post-cut for salamanders, the predicted mean proportion of recaptured adults in the 30m treatment was only 62% and 40%, respectively, of that in the reference treatment. Frog sex ratio and abundance did not differ across treatments, but salamander sex ratios were increasingly male-biased in both cut treatments. By the final year, there were on average, only about 40% and 65% as many females predicted in the 100m and 30m treatments, respectively, compared to the first year. Breeding salamanders at short-hydroperiod pools were about 10% as abundant in the 100m versus reference treatment. Our study demonstrates that buffers partially mitigate the impacts of habitat disturbance on wetland-dependent amphibians, but buffer width and hydroperiod critically mediate that process. We provide the first experimental evidence showing that 30-m-wide buffers may be insufficient for maintaining resilient breeding populations of pool-dependent amphibians, at least during the first six years post-disturbance

Net Costs of Wildlife Damage on Private Lands

This study models net welfare impacts on producers who receive utility from on-farm wildlife populations that are not costlessly disposable. Wildlife damage levels where net benefits are zero indicate producers' maximum willingness to pay for on-farm wildlife. An empirical model is developed. Results for Ontario producers suggest the net welfare loss from damage is approximately half of the value of the yield loss for those with damage. In aggregate, however, on-farm wildlife generates net benefits to producers that outweigh costs by about 10-to-1. The distribution of net benefits is highly skewed across producers.random effects probit, tolerance thresholds, wildlife benefits, wildlife damage, Resource /Energy Economics and Policy,

Using Bid Design to Measure the Boundaries of WTP

We examine the extent to which bid design provides an informative anchor that influences the context in which individuals evaluate willingness to pay questions. We postulate that agents who are uncertain over possible states of nature that may arise when consuming a good use bid design as a means to resolve such uncertainty. Furthermore, we hypothesize that the impact of bid design on estimated WTP is less pronounced for experienced agents that have observed more draws from nature. We use three measure of bid design to evaluate our conjectures; (i) the mean of bid amounts, (ii) the absolute value of the difference between bid amounts, and (iii) the ratio of the mean to the spread. We interact proxies for individual experience with our measure of bid design to evaluate if such characteristics attenuate the impact of bid design on WTP estimates. We find the likelihood an individual says Yes to a given bid systematically varies with measures of bid design. This suggests that bid design provides an informative anchor and can be used to identify probabilistic boundaries for WTP.Demand and Price Analysis,