Modern energy region development and income distribution: An input-output analysis

This paper formulates an input-output method for determining the distributional consequences of energy development projects. The method is oriented to the conditions appearing in many contemporary development settings where large resident populations and other factors are likely to inhibit boomtown scenarios. An analysis of geothermal energy development in Imperial County, California, is presented. The results indicate that personal income inequality is likely to increase by several percentage points as measured by the Gini coefficient. The sensitivity of the results is examined with respect to important factors such as labor supply elasticities, preferential employment of local residents, and the concentration of land holdings.     

Gaseous nitrogen emissions and mineral nitrogen transformations as affected by reclaimed effluent application

Irrigation with reclaimed effluent (RE) is essential in arid and semiarid regions. Reclaimed effluent has the potential to stimulate gaseous N losses and affect other soil N processes. No direct measurements of the N2 and N2O emissions from Mediterranean soils have been conducted so far. We used the 15N gas flux method in a field and a laboratory experiment to study the effect of RE irrigation on gaseous N losses and other N transformations in a Grumosol (Chromoxerert) soil. The fluxes of N2, N2O, and NH3 were measured from six Grumosol lysimeters following application of either fresh water or RE. The N fertilizer was applied either as 15NH4 or 15NO3. Only up to 0.3% from the applied N fertilizer was lost as N2O + NH3. Reclaimed effluent enhanced the losses of NH3, but did not affect those of N2O. Nitrification and denitrification were equally important to N2O production. Laboratory incubations were performed to both confirm the influence of the irrigation water type and to test the effect of moisture content. Significant quantities of N2 and N2O (up to 3.1% of the applied fertilizer) were emitted from saturated soils. Reclaimed effluent application did not induce higher N2O emissions, yet significantly more (approximately 33%) N2 was emitted from RE-irrigated soils. Denitrification contributed up to 75% of the N2O amounts emitted from saturated soils. Reclaimed effluent application inhibited nitrification in the Grumosol by 15 to 25% and induced NO2 accumulation in soils incubated at a field-capacity moisture content.     

Formation of Reactive Gaseous Mercury in the Arctic: Evidence of Oxidation of Hg° to Gas-Phase Hg-II Compounds after Arctic Sunrise

We have measured total gaseous mercury concentrations(Hg°) at Point Barrow, Alaska since September 1998 in aneffort to determine the geographic extent and reaction mechanismof the so-called mercury depletion events (MDE) previouslyreported in the high Arctic at Alert, Canada. Hg° has beensampled now for nearly 2 years at Barrow. In September, 1999, webegan making the first automated measurements of reactive gaseousmercury (RGM) attempted in the Arctic, along with measurements ofHg accumulation in snowpack to determine the fate of the depleted Hg°. During the fall and early winter, Hg°and RGM exhibit only minor variation, Hg° remaining within10% of global background, near 1.6–1.8 ng m^-3. The MDEperiods are quite different, however; within days of Arcticsunrise in January, Hg° exhibits major variations from themean, rapidly dropping as low as 0.05 ng m^-3 and then cyclingback to typical levels, sometimes exceeding global background. These events continue throughout Arctic spring, then end abruptlyfollowing snowmelt, in early June. Prior to Arctic sunrise, RGMremains near detection (<2 pg m^-3), but after sunriseincreases dramatically (to levels as high as 900 pg/m³) insynchrony with the depletion of Hg°. Both phenomenaexhibit a strong diel cycle, in parallel with UV-B. We concludethat MDE's involve rapid in-air oxidation of Hg° to aspecies of RGM by photochemically-driven reactions, probablyinvolving the same reactive bromine and chlorine compoundsinvolved in ozone destruction. Sharp increases in Hg in thesurface snowpack after sunrise coincident with periods of peakRGM suggest surface accumulation of the RGM by dry deposition.     

Some observations on the geochemistry and isotopic composition of uranium in relation to the reprocessing of nuclear fuels

In order to determine whether or not uranium depleted in ²³⁵U and derived from the British Nuclear Fuels Ltd (BNFL) nuclear fuel reprocessingg plant at Sellafield, Cumbria, UK can be detected in environmental samples, we have investigated the isotopic composition of uranium in ammonium carbonate leachates from marine and terrestial samples from near Sellafield. Some show a depletion in ²³⁵U and the presence of ²³⁶U which unequivocally identifies the presence of uranium derived from BNFL. The ²³⁴U/²³⁸U activity ratio and total uranium content of samples are not significantly different from those of natural uranium abundances. The highest concentrations of uranium are found in anaerobic organic-rich silts and the lowest in sandy silts and coarse-grained sands.     

Values and Economics in Environmental Management: A Perspective and Critique

Several categories of non-market value have been identified for forests and other natural environments: use value, option value, altruism, bequest value, existence value and intrinsic value. In this paper, we view these values from a psychological perspective. Non-market values arise because natural resources play important roles in furthering human goals. This goal perspective contrasts with intrinsic value—the idea that natural objects have value as ends in themselves regardless of their relationship to man. Because of the lack of precise definitions, elements of intrinsic value are often mixed with existence value, creating confusion in the literature. These resource values need to be examined on a logical as well as an empirical basis. We argue that careful scrutiny reveals problems with both existence value and intrinsic value so that it is important to question their role in policy formation and analysis.