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131.
ABSTRACT: The purpose of this paper is to describe a land use and environmental planning model. Map overlays were used for analyzing and aggregating economic, social, and environmental data. Various land use categories were evaluated using a numerical scoring system. These scores were then used to assist in the development of land use regulations in a coastal county in South Carolina.  相似文献   
132.
ABSTRACT: The Federal Government's interest and involvement in water resource development in discussed in the context of project financing and cost sharing. After drawing a clear distinction between the two issues - who puts up the money, and who repays over time - the authors survey a number of Federal acts from which have evolved nearly 200 separate cost-sharing rules. Selected cost sharing and financing issues discussed include consistency in policies, rehabilitation of urban water supply systems, multipurpose water quality projects, and ground water management. Two proposals for cost/finance sharing reform introduced in the 96th Congress are discussed in detail and their impacts compared with current policy. The joint venture approach (Administration proposal) results in an effective composite cost share which changes significantly but not drastically (from 19 to 35 percent non-Federal share for a hypothetical project). The block grant approach (Domenici-Moynihan proposal) would alter the regional distribution of Federal water developement funding from the South and West to the Northwest and North Central States.  相似文献   
133.
ABSTRACT: Spatial variability of infiltration rates was examined for a site in southern Idaho. Data used represented 13 sampling dates over a 5-year period. Samples initially were taken within a native big sagebrush community, again after plowing and seeding to crested and intermediate wheatgrass, and then while the seeded area was being grazed by domestic livestock. Results indicate that either a normal or log normal distribution may be adequate for describing measured infiltration rates.  相似文献   
134.
Little attention has been paid to the environmental fate of the hormones 17beta-estradiol and testosterone excreted in animal waste. Land application of manure has a considerable potential to affect the environment with these endocrine disrupting compounds (EDCs). Composting is known to decompose organic matter to a stable, humus-like material. The goal of the present study was to quantitatively assess levels of water-soluble 17beta-estradiol and testosterone in composting chicken manure with time. Chicken layer manure was mixed with hay, straw, decomposed leaves, and starter compost, adjusted to approximately 60% moisture, and placed into a windrow. A clay-amended windrow was also prepared. Windrows were turned weekly, and temperature, oxygen, and CO(2) in the composting mass were monitored for either 133 or 139 d. Commercial enzyme immunoassay kits were used to quantitate the levels of 17beta-estradiol and testosterone in aqueous sample extracts. Water-soluble quantities of both hormones diminished during composting. The decrease in 17beta-estradiol followed first-order kinetics, with a rate constant k = -0.010/d. Testosterone levels declined at a slightly higher rate than 17beta-estradiol (i.e., k = -0.015/d). Both hormones could still be measured in aqueous extracts of compost sampled at the conclusion of composting. The decline in water-soluble 17beta-estradiol and testosterone in extracts of clay-amended compost was not statistically different from normal compost. These data suggest that composting may be an environmentally friendly technology suitable for reducing, but not eliminating, the concentrations of these endocrine disrupting hormones at concentrated animal operation facilities.  相似文献   
135.
This paper presents a method for assessing a community's sustainability prospects at a point in time. It argues that an improved methodology is needed to support the development of local area indicators. The method presented is community sustainability auditing. The ethical, conservative, competitive and co-operative aspects of sustainability are emphasized.The method uses an indicator approach within a protocol loosely inspired by International Standards Organization procedures. This involves the development of a set of questions for audit purposes, definition of indicators, analysis of the indicators in the light of the questions and a report summarizing a community's sustainability prospects.  相似文献   
136.
Summary Hamilton and Zuk proposed that bright male plumage may have evolved in males of polygynous species as a result of female preferences for males that are able to demonstrate their resistance to disease. They predicted an inverse correlation between female mating preferences and the level of parasitic infection of males. We found such a correlation between the level of infection by a common ectoparasite (Myrsidea ptilonorhynchi: Menoponidae) and mating success of male satin bowerbirds (Ptilonorhynchus violaceus). In addition, we tested and were able to confirm three other predictions derived from their model: that (1) older males had fewer parasites than their younger counterparts, (2) levels of individual parasitic infection are highly correlated between years, and (3) that individuals resighted in successive years are less parasitized than those that fail to return. These results support the bright male model, but they are also consistent with two other hypotheses that may explain plumage dimorphism based on the level of parasitic infection. The correlated infection model suggests that females choose males with few ectoparasites because of a correlation between the level of ectoparasitic infection and heritable resistance to internal infections. In the parasite avoidance model, females favor parasitefree males because it lowers their own prospects for parasitic infection. Our data did not show the predicted relationship between parasite numbers with plumage quality that is needed to support the bright male hypothesis, nor did it show the inverse correlation between male condition and parasite numbers that is predicted by both the bright male and correlated infection hypotheses. Our results are most consistent with the parasite avoidance hypothesis.  相似文献   
137.
Potent estrogenic hormones are consistently detected in the environment at low concentration, yet these chemicals are strongly sorbed to soil and are labile. The objective of this research was to improve the understanding of the processes of sorption, mobility, and transformation for estrogens in natural soils, and their interaction. Equilibrium and kinetic batch sorption experiments, and a long-term column study were used to study the fate and transport of 17beta-estradiol and its primary metabolite, estrone, in natural soil. Kinetic and equilibrium batch experiments were done using radiolabeled 17beta-estradiol and estrone. At the concentrations used, it appeared that equilibrium sorption for both estrogens was achieved between 5 and 24 h, and that the equilibrium sorption isotherms were linear. The log K(oc) values for 17beta-estradiol (2.94) and estrone (2.99) were consistent with previously reported values. Additionally, it was found that there was rate-limited sorption for both 17beta-estradiol (0.178 h(-1)) and estrone (0.210 h(-1)). An approximately 42 h long, steady-flow, saturated column experiment was used to study the transport of radiolabeled 17beta-estradiol, which was applied in a 5.00 mg L(-1) solution pulse for 44 pore volumes. 17beta-estradiol and estrone were the predominant compounds detected in the effluent. The effluent breakthrough curves were asymmetric and the transport modeling indicated that sorption was rate-limited. Sorption rates and distributions of the estrogens were in agreement between column and batch experiments. This research can provide a better link between the laboratory results and observations in the natural environment.  相似文献   
138.
139.
Perfluorooctanesulfonyl fluoride (POSF, C8F17SO2F) related-materials have been used as surfactants, paper and packaging treatments, and surface (e.g., carpet, textile, upholstery) protectants. A metabolite, perfluorooctanesulfonate (PFOS, C8F17SO3), has been identified in the serum and liver of non-occupationally exposed humans and wildlife. Because of its persistence, an important question was whether elderly humans might have higher PFOS concentrations. From a prospective study designed to examine cognitive function in the Seattle (WA) metropolitan area, blood samples were collected from 238 dementia-free subjects (ages 65–96). High-pressure liquid chromatography-electrospray tandem mass spectrometry determined seven fluorochemicals: PFOS; N-ethyl perfluorooctanesulfonamidoacetate; N-methyl perfluorooctanesulfonamidoacetate; perfluorooctanesulfonamidoacetate; perfluorooctanesulfonamide; perfluorooctanoate; and perfluorohexanesulfonate. Serum PFOS concentrations ranged from less than the lower limit of quantitation (3.4 ppb) to 175.0 ppb (geometric mean 31.0 ppb; 95% CI 28.8–33.4). An estimate of the 95% tolerance limit was 84.1 ppb (upper 95% confidence limit 104.0 ppb). Serum PFOS concentrations were slightly lower among the most elderly. There were no significant differences by sex or years residence in Seattle. The distributions of the other fluorochemicals were approximately an order of magnitude lower. Similar to other reported findings of younger adults, the geometric mean serum PFOS concentration in non-occupational adult populations likely approximates 30–40 ppb with 95% of the population’s serum PFOS concentrations below 100 ppb.  相似文献   
140.
The broad climatological features associated with the Asian monsoon circulation, including its mean state and intraseasonal and interannual variability over the Indian subcontinent as simulated in the National Center for Atmospheric Research (NCAR) global coupled climate system model (CSM) in its control reference experiment, are presented in this paper. The CSM reproduces the seasonal cycle as well as basic observed patterns of key climatic parameters reasonably well in spite of some limitations in simulation of the monsoon rainfall. However, while the seasonality in rainfall over the region is simulated well, the simulated area-averaged monsoon rainfall is underestimated to only about 60% of the observed rainfall. The centers of maxima in simulated monsoon rainfall are slightly displaced southward as compared to the climatological patterns. The cross-equatorial flow in simulated surface wind patterns during summer is also stronger than observed with an easterly bias. The transient experiment with a 1% per year compound increase in CO2 with CSM suggests an annual mean area-averaged surface warming of about 1.73 °C over the region at the time of CO2 doubling. This warming is more pronounced in winter than during the monsoon season. A net increase in area-averaged monsoon rainfall of about 1.4 mm day–1, largely due to increased moisture convergence and associated convective activity over the land, is obtained. The enhanced intraseasonal variability in the monsoon rainfall in a warmer atmosphere is confined to the early part of the monsoon season which suggests the possibility of the date of onset of summer monsoon over India becoming more variable in future. The enhanced interannual and intraseasonal variability in the summer monsoon activity over India could also contribute to more intense rainfall spells over the land regions of the Indian subcontinent, thus increasing the probability of extreme rainfall events in a warmer atmosphere. Electronic Publication  相似文献   
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