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951.
Randall J. Schaetzl L. Keith Hendrie Scott W. Kirsch 《Journal of the American Water Resources Association》1989,25(5):1023-1030
ABSTRACT: Soil water was monitored by neutron scattering in six soils, three each within two drainage catenas in east-central Illinois, over a 15-month time span. The prairie soils have formed in: (1) 76–152 cm of silt loam, eolian sediments (bess) over glacial till (Catlin-Flanagan-Drummer catena), and (2) bess greater than 152 cm in thickness (Tama-Ipava-Sable catena). We characterized the water content of these soils over the total time span and for wet and dry climatic subsets, as an aid to potential irrigation decisions. Soils of the thin bess, C-F-D catena dried out to lower water contents and had greater soil water variability than did the thick bess soils. Under wet conditions, soil water contents in the two catenas were quite similar. Alleviation of surface and subsurface drying via irrigation would thus be more advantageous to yields on the C-F-D soils than on the T-I-S soils. 相似文献
952.
Clayton L. Hanson 《Journal of the American Water Resources Association》1989,25(1):159-164
ABSTRACT: The Wyoming shield and dual-gage measuring systems were developed to measure all precipitation, but more specifically snowfall under windy conditions. Results of a study at five sites on the Reynolds Creek Experimental Watershed in southwest Idaho indicate that gages with Wyoming shields and the dual-gage system measured the same amount when air temperatures were higher than ?2.2°C. Precipitation amounts computed from the dual. gage system were slightly more than from gages with Wyoming shields for snowfall, especially under windy conditions. Results also show how well the Alter shielded and unshielded gages used in the dual-gage system represent the computed catch if data were only available from one or the other of the gages. 相似文献
953.
Jeffery J. Himmelberger Samuel J. Ratick Allen L. White 《Environmental management》1991,15(5):647-658
This article analyzes the recent negotiations connected with siting 24 solid-waste landfills in Wisconsin. We examine the
association between the type and amount of compensation paid to host communities by facility developers and the size of facilities,
certain facility characteristics, the timing of negotiated agreements, the size of the host community, and the socioeconomic
status of the host area. Our findings suggest that the level of compensation after adjusting for landfill capacity is positively
associated with the percentage of total facility capacity dedicated to host community use, positively associated with the
percentage of people of the host area who are in poverty, and larger for public facilities that accept municipal wastes. Other
explanatory variables we examined, whose association with levels of compensation proved statistically insignificant, were
facility size, facility status (new vs expansion), facility use (countyonly vs multicounty), timing of negotiation, host community
size, and the host area education level, population density, and per capita income. We discuss the policy implications of
our principal findings and future research questions in light of the persistent opposition surrounding the siting of solid-waste
and other waste-management facilities. 相似文献
954.
The land evaluation and site assessment (LESA) method has been used extensively in the United States to assess agricultural
land suitability for different localities. Despite widespread use, LESA models rarely have been evaluated in a systematic,
comprehensive manner. This article discusses development of a LESA system for Hawaii, the first statewide application of the
LESA methodology. The empirical model was implemented with a computerized geographic information system (GIS). The system's
efficiency, ability to discriminate among land parcels, and robustness to subjective model parameter values are evaluated
with statistical analyses and map overlays of GIS data. Results show great potential to simplify the original model specification,
primarily through deletion of marginal site assessment factors. System output was generally insensitive to the numeric values
selected for model parameters, with exception of the ratio used to combine the land evaluation (LE) and site assessment (SA)
component scores. Relative supplies of the differing land attributes measured by the two components must be considered in
determining an appropriate LE:SA ratio for a given area. 相似文献
955.
956.
Traditional command-and-control regulations provide few opportunities for total quality environmental management because they usually do not take into account cost and efficiency factors. However, in the past several years both Congress and EPA have shown increasing interest in using incentive-type approaches to regulate the environment. These include taxes, marketable pollution privileges, deposits and refunds, information disclosure provisions, and subsidies. The author details examples of each and discusses how they can effectively complement a quality program. 相似文献
957.
958.
Social support has been suggested as important for newcomer adjustment to an organization. The present paper reports a longitudinal study of 91 newcomers to three separate organizations. The effects of availability and helpfulness of 10 sources of social support on newcomers reports of psychological distress, satisfaction, intention to leave, and their supervisors assessment of their performance rating (N of supervisors = 41; n of ratings = 91) were examined. The availability of support activities such as offsite training sessions and business trips were found to be associated with decreased psychological symptoms. Helpfulness of various relationship supports were associated with positive adjustment. These results are discussed within the context of attachment theory and our knowledge of social support in work settings. 相似文献
959.
Morris L. Maslia Mustafa M. Aral Robert C. Williams Allan S. Susten Janet L. Heitgerd 《Journal of the American Water Resources Association》1994,30(6):1025-1041
ABSTRACT: Simulation of ground-water flow and fate of contaminants in the subsurface environment constitutes a major phase of most environmental assessment and site remediation studies. These simulation studies yield information on spatial and temporal distributions of contaminants in the subsurface media. An important use of this information is to conduct exposure assessment studies. Spatial and temporal distributions of both chemical concentrations and exposed populations render this integrated exposure analysis task rather difficult. Geographic Information Systems (GIS), on the other hand, provide a platform in which layered, spatially distributed databases can be manipulated with ease, thereby simplifying exposure analysis tasks significantly. In this paper, we describe procedures that combine the simulation models and demographic databases under a GIS platform to automate the exposure assessment phase of a typical health assessment study. Procedures developed herein significantly simplify the post-processing phase of the analysis, and render the overall task more ‘user friendly.’ A site-specific application is included as a demonstration of the proposed process. 相似文献
960.
John B. Erdmann Heinz G. Stefan Patrick L. Brezonik 《Journal of the American Water Resources Association》1994,30(6):1043-1053
ABSTRACT: Suspended solids and ammonium concentration profiles measured at five locations in Duluth-Superior Harbor during July-October 1985 were analyzed to quantify wind and ship effects on sediment resuspension and resulting harbor water quality. Wind components from the SE quadrant correlated strongly with depth-averaged suspended solids concentrations that were unaffected by ship passage or thermal stratification. Winds from that quadrant have the largest fetch in the harbor. The highest correlation (r2= 0.93) was with the 6-hour average of the ESE wind velocity component. Multiple linear regression analysis of data from post-ship passage concentration profiles yielded numerical estimates of settling velocities of 0.08 to 0.25 cm s?1, typical of ship-resuspended sediments, and vertical eddy diffusivities of 4 to 13 cm2 s1. The results suggest that ambient vertical eddy diffusivities in the harbor are less than 4 cm2 s?1 in the absence of ship passages and with winds less than 5 m s?1 (10 knots). 相似文献