1. The Alaskan Matanuska- Susitna Basin ( MSB) provides habitat for all five Pacific salmon species, and their large seasonal spawning runs are important both ecologically and economically. However, the encroachment o...
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1. The Alaskan Matanuska- Susitna Basin ( MSB) provides habitat for all five Pacific salmon species, and their large seasonal spawning runs are important both ecologically and economically. However, the encroachment of human development through urbanization and extractive industries poses a serious risk to salmon habitat in the MSB. 2. Using systematic conservation planning techniques, different methods of incorporating anthropogenic risks were assessed to determine how to conserve salmon habitat in the area cost- effectively. 3. The consequences of four distinct conservation scenarios were quantified: no consideration either of urbanization or extractive industries (` Risk ignored' scenario);accounting for the risk of urbanization, and avoiding conservation in all areas rich in fossil fuels (` Urbanization accounted, all extraction avoided' scenario);accounting for urbanization and oil and gas development, but avoiding conservation in coalrich areas (` Urbanization accounted, coal areas avoided' scenario);and accounting for all anthropogenic risks to habitat, and allowing conservation in oil, gas, or coal- rich areas (` All risks accounted' scenario). To compare conservation success and resilience, the impacts of these risks were estimated using Monte Carlo simulations. The final cost of each solution was then divided by the number of conservation targets met to determine a return on investment. 4. Results from scenarios that avoided all extractive activities, or only coal, suggest that conservation targets cannot be met simply by avoiding areas rich in fossil fuels, and these scenarios resulted in lower returns on investment than those in which risks from extraction were incorporated into the solution. 5. By developing a method for setting priorities that are economically based, this study provides a method for local managers and conservation groups to identify conservation opportunities in MSB river basins.
Three-dimensional and two-dimensional simulation tools were made and time-dependent circulations of water in large scale artificial basins were examined for thermal energy storage. Natural and forced convection with a...
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Three-dimensional and two-dimensional simulation tools were made and time-dependent circulations of water in large scale artificial basins were examined for thermal energy storage. Natural and forced convection with advection-diffusion energy transport cause these circulations. This paper focuses on basins filled with porous media. The modified Boussinesq equations for porous media and the finite element method were used. The time integrator for the transport equation is explicit for advection and implicit for diffusion, second-order accurate and of the streamline upwind type. Continuous experimental data from the Stuttgart artificial aquifer field test site has been collected for several years. These measurements were compared to many finite element simulation results. Later the simulation tools were applied and two- and three-dimensional basin geometries of up to 20 000 m(3) volume were studied.
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