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961.
Forest policymakers, public lands managers, and scientists in the Pacific Northwest (USA) seek ways to evaluate the landscape-level
effects of policies and management through the multidisciplinary development and application of spatially explicit methods
and models. The Interagency Mapping and Analysis Project (IMAP) is an ongoing effort to generate landscape-wide vegetation
data and models to evaluate the integrated effects of disturbances and management activities on natural resource conditions
in Oregon and Washington (USA). In this initial analysis, we characterized the spatial distribution of forest and range land
development in a four-county pilot study region in central Oregon. The empirical model describes the spatial distribution
of buildings and new building construction as a function of population growth, existing development, topography, land-use
zoning, and other factors. We used the model to create geographic information system maps of likely future development based
on human population projections to inform complementary landscape analyses underway involving vegetation, habitat, and wildfire
interactions. In an example application, we use the model and resulting maps to show the potential impacts of future forest
and range land development on mule deer (Odocoileus hemionus) winter range. Results indicate significant development encroachment and habitat loss already in 2000 with development located
along key migration routes and increasing through the projection period to 2040. The example application illustrates a simple
way for policymakers and public lands managers to combine existing data and preliminary model outputs to begin to consider
the potential effects of development on future landscape conditions. 相似文献
962.
Paul B. Thompson 《Journal of Agricultural and Environmental Ethics》2010,23(3):209-227
Recent publications by Pogge (Global ethics: seminal essays. St. Paul: Paragon House 2008) and by Singer (The life you can save: acting now to end world poverty. New York: Random House 2009) have resuscitated a debate over the justifiability of famine relief between Singer and ecologist Garrett Hardin in the 1970s.
Yet that debate concluded with a general recognition that (a) general considerations of development ethics presented more
compelling ethical problems than famine relief; and (b) some form of development would be essential to avoiding the problems
of growth noted by Hardin. Better than renewing the debate, we should recognize two points. First, food needs do indeed evoke
a moral response that is more direct and compelling than the philosophical positions often generated to rationalize a duty
to bring aid. As such the argument for feeding hungry people cannot be generalized into a paradigm for development ethics
without distortions that undercut the morally valid elements in Singer’s original argument. Second, contrary to prevailing
assumptions in present day development ethics, food aid and famine relief continue to be important priorities for international
agencies, notably the World Food Program. Emergency food assistance, the nominal topic of Singer’s original article, thus
is an important issue for agricultural as well as development ethics, though one that should indeed be seen as distinct from
more complex duties to address the conditions of chronic poverty and underdevelopment. 相似文献
963.
964.
Scott M. Payne William W. Woessner 《Journal of the American Water Resources Association》2010,46(5):1003-1023
Payne, Scott M. and William W. Woessner, 2010. An Aquifer Classification System and Geographical Information System-Based Analysis Tool for Watershed Managers in the Western U.S. Journal of the American Water Resources Association (JAWRA) 46(5):1003-1023. DOI: 10.1111/j.1752-1688.2010.00472.x Abstract: Aquifers and groundwater systems can be classified using a variety of independent methods to characterize geologic and hydraulic properties, the degree of connection with surface water, and geochemical conditions. In light of a growing global demand for water, an approach for classifying groundwater systems at the watershed scale is needed. A comprehensive classification system is proposed that combines recognized methods and new approaches. The purpose of classification is to provide groundwater professionals, policy makers, and watershed managers with a widely applicable and repeatable system that reduces sometimes cumbersome complex databases and analyzes to straightforward terminology and graphical representations. The proposed classification system uses basin geology, aquifer productivity, water quality, and the degree of groundwater/surface water connection as classification criteria. The approach is based on literature values, reference databases, and fundamental hydrologic and hydrogeologic principles. The proposed classification system treats dataset completeness as a variable and includes a tiered assessment protocol that depends on the quality and quantity of data. In addition, it assembles and catalogs groundwater information using a consistent set of nomenclature. It is designed to analyze and display results using Geographical Information System mapping tools. 相似文献
965.
Wang Y Li Y Kim H Walker SL Abriola LM Pennell KD 《Journal of environmental quality》2010,39(6):1925-1933
Commercial production and use of fullerene (C60) nanomaterials will inevitably lead to their release into the environment, where knowledge of C60 fate and transport is limited. In this study, a series of one-dimensional column experiments was conducted to assess the transport and retention of nanoscale fullerene aggregates (nC60) in water-saturated soils. Under the experimental conditions, complete retention of nC60 was observed in columns (2.5 cm inside diameter x 11 cm length) packed with Appling or Webster soil, which contain 0.75 and 3.33% organic carbon by weight, respectively. When the volume of aqueous nC60 suspension (approximately 4.5 mg L(-1)) applied to Appling soil was increased from 5 to 65 pore volumes, the travel distance increased from 3 to 8 cm, and the retention capacity approached a limiting value of 130 microg g(-1), although nC60 was not detected in the column effluent. The addition of 20 mg C L(-1) Suwannee River humic acid to the influent suspension increased the nC60 transport in Appling soil but did not resul in breakthrough. Attempts to simulate the experimental data using clean-bed filtration theory were not satisfactory, yielding retention profiles that failed to match observed data. Subsequent incorporation of a limiting retention capacity expression into the mathematical model resulted in accurate predictions of the measured nC60 retention profiles and transport behavior. The sizable retention capacities observed in this study suggest that transport of nC60 is limited in relatively fine-textured soils containing appreciable amounts of clay minerals and organic matter, with substantial accumulation of nC60 aggregates near the point of release. 相似文献
966.
Unrine JM Tsyusko OV Hunyadi SE Judy JD Bertsch PM 《Journal of environmental quality》2010,39(6):1942-1953
To investigate the role of particle size on the oxidation, bioavailability, and adverse effects of manufactured Cu nanoparticles (NPs) in soils, we exposed the earthworm Eisenia ferida to a series of concentrations of commercially produced NPs labeled as 20- to 40-nm or < 100-nm Cu in artificial soil media. Effects on growth, mortality, reproduction, and expression of a variety of genes associated with metal homeostasis, general stress, and oxidative stress were measured. We also used X-ray absorption spectroscopy and scanning X-ray fluorescence microscopy to characterize changes in chemical speciation and spatial distribution of the NPs in soil media and earthworm tissues. Exposure concentrations of Cu NPs up to 65 mg kg(-1) caused no adverse effects on ecologically relevant endpoints. Increases in metallothionein expression occurred at concentrations exceeding 20 mg kg(-1) of Cu NPs and concentrations exceeding 10 mg kg(-1) of CuSO4. Based on the relationship of Cu tissue concentration to metallothionein expression level and the spatial distribution and chemical speciation of Cu in the tissues, we conclude that Cu ions and oxidized Cu NPs were taken up by the earthworms. This study suggests that oxidized Cu NPs may enter food chains from soil but that adverse effects in earthworms are likely to occur only at relatively high concentrations (> 65 mg Cu kg(-1) soil). 相似文献
967.
Emma Ter Mors Mieneke W.H. Weenig Naomi Ellemers Dancker D.L. Daamen 《Journal of environmental psychology》2010,30(4):347-357
This experimental research addresses the effectiveness of communication about complex environmental issues, depending on whether the same information is provided by multiple collaborating or by individual organizations (i.e., stakeholders). The information provided pertains to carbon dioxide capture and storage (CCS) technology, as an example of a complex environmental issue. In Studies 1 (N = 75) and 2 (N = 66) we found that participants perceived factual information from collaborating stakeholders to be of higher quality than when the same information was provided by individual stakeholders. As predicted, the expectation of diverse perspectives being represented in the collaborative information mediated this effect. In addition, in Study 3 (N = 79) the perceived dissimilarity of collaborating stakeholders was shown to be an important precondition for the collaboration effect observed in Studies 1 and 2. Finally, these studies indicate that occasional collaboration between different stakeholders does not necessarily harm the perceived credibility of each individual stakeholder. 相似文献
968.
S. O. Asagba G. E. Eriyamremu J. O. T. Emudainohwo I. Okoro 《The Environmentalist》2010,30(3):260-266
The activities of some oxidative enzymes (aldehyde oxidase, AO, EC 1.2.3.1; xanthine oxidase, XO, EC 1.17.3.2; sulphite oxidase,
SO, EC 1.8.3.1; and monoamine oxidase, MO, EC 1.4.3.4) were investigated in the liver, gill, kidney, brain and muscle of a
variety of African catfish (Clarias gariepinus) after 7 and 21 days of exposure to 0.1, 0.2 and 0.4 ppm cadmium (Cd) in ambient water. MO, SO and AO activities were significantly
(p < 0.05) decreased in a dose-dependent manner in the liver, kidney and gill in the 7-day Cd-exposed fish when compared to
control. Conversely, brain MO, AO and SO activities were significantly (p < 0.05) elevated in a dose-dependent manner in the same fishes relative to control. As in the 7-day Cd-exposed fish, the
activities of MO, AO and SO were significantly (p < 0.05) decreased in a dose-dependent manner in the gill, kidney and liver of catfish exposed for 21 days. Same is true for
XO in these organs after both duration of exposure, except in the liver where no significant change was observed relative
to control. The inhibition of these oxidative enzymes in the liver, gill and kidney of catfish may interfere with their biotransformation
function, and ultimately the survival of the fish may be compromised. 相似文献
969.
970.