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71.
The present study, as an extension of Mitchell and Woods (1980), examined the relationships between supervisor and subordinate variables and disciplinary action severity in a field setting. Hypotheses were tested using questionnaire data from nursing supervisors. Analyses confirmed that supervisor attributions, severity of the incident of poor performance, supervisor intent, and subordinate work history were related to disciplinary action severity. Moreover, regression analysis indicated that severity of the incident of poor performance was the largest contributor to the choices of a disciplinary action. Implications of the study for organizations and future research are discussed. 相似文献
72.
Agroecosystems,nitrogen-use efficiency,and nitrogen management 总被引:11,自引:0,他引:11
The global challenge of meeting increased food demand and protecting environmental quality will be won or lost in cropping systems that produce maize, rice, and wheat. Achieving synchrony between N supply and crop demand without excess or deficiency is the key to optimizing trade-offs amongst yield, profit, and environmental protection in both large-scale systems in developed countries and small-scale systems in developing countries. Setting the research agenda and developing effective policies to meet this challenge requires quantitative understanding of current levels of N-use efficiency and losses in these systems, the biophysical controls on these factors, and the economic returns from adoption of improved management practices. Although advances in basic biology, ecology, and biogeochemistry can provide answers, the magnitude of the scientific challenge should not be underestimated because it becomes increasingly difficult to control the fate of N in cropping systems that must sustain yield increases on the world's limited supply of productive farm land. 相似文献
73.
Land-use suitability analysis in the United States: historical development and promising technological achievements 总被引:19,自引:1,他引:18
Various methods of spatial analysis are commonly used in land-use plans and site selection studies. A historical overview
and discussion of contemporary developments of land-use suitability analysis are presented. The paper begins with an exploration
into the early 20th century with the infancy of documented applications of the technique. The article then travels through
the 20th century, documenting significant milestones. Concluding with present explorations of advanced technologies such as
neural computing and evolutionary programming, this work is meant to serve as a foundation for literature review and a premise
for the exploration of new advancements as we enter into the 21st century. 相似文献
74.
Poerschmann J Gathmann A Augustin J Langer U Górecki T 《Journal of environmental quality》2005,34(5):1508-1518
Transformation of crops, including maize (Zea mays L.), with the cry1Ab gene from Bacillus thuringiensis to combat lepidopteran pests results in pleiotropic effects regarding lignin biosynthesis. Lignin patterns in stems and leaves of two genetically modified Bt-maize varieties (Novelis T and Valmont T) were studied along with their non-Bt near-isolines (Nobilis and Prelude, respectively). Molecular-level based thermochemolysis using tetramethylammonium hydroxide (TMAH) in combination with gas chromatography-mass spectrometry (GC-MS) was used to quantitate the total lignin contents and to identify monomeric lignin subunits including p-hydroxyphenyl (P), guaiacyl (G), and syringyl (S) moieties. The results were supplemented and confirmed by cupric oxide oxidation. The stems of the transgenic lines had higher concentrations of total lignin than the respective isogenic lines: Valmont T/Prelude by 18% and Novelis T/Nobilis by 28%. In contrast, differences in the total lignin concentration of leaves between the transgenic and the respective near-isogenic lines were marginal. There were significant modifications in the ratio of p-hydroxyphenyl/guaiacyl/syringyl molecular marker units of stem lignin between transgenic and isogenic lines. The guaiacyl units (in particular the G18 marker) accounted chiefly for the higher total lignin contents in the transgenic lines. The leaf lignin patterns did not show significant differences in molecular markers between isogenic and transgenic lines. TMAH-induced thermochemolysis--conducted in both the on-line and off-line modes--provided detailed information on the molecular composition of lignin, thus proving superior to the established "wet chemistry" methods of lignin determination. 相似文献
75.
Frederick Steiner Scott Pieart Edward Cook Jacqueline Rich Virginia Coltman 《Environmental management》1994,18(2):183-201
The protection of wetlands and riparian areas has emerged as an important environmental planning issue. In the United States,
several federal and state laws have been enacted to protect wetlands and riparian areas. Specifically, the federal Clean Water
Act includes protection requirements in Sections 301 and 303 for state water quality standards, Section 401 for state certification
of federal actions (projects, permits, and licenses), and Section 404 for dredge and fill permits. The Section 401 water quality
state certification element has been called the “sleeping giant” of wetlands protection because it empowers state officials
to veto or condition federally permitted or licensed activities that do not comply with state water quality standards. State
officials have used this power infrequently. The purpose of this research was to analyze the effectiveness of state wetland
and riparian programs. Contacts were established with officials in each state and in the national and regional offices of
key federal agencies. Based on interviews and on a review of federal and state laws, state program effectiveness was analyzed.
From this analysis, several problems and opportunities facing state wetland protection efforts are presented. 相似文献
76.
William W. Budd Paul L. Cohen Paul R. Saunders Frederick R. Steiner 《Environmental management》1987,11(5):587-597
King County, Washington is a part of the rapidly growing Pacific Northwest region. This growth has placed pressure on stream corridors. Past studies about regional stream corridors provide a rich source of information for environmental planners and managers. This article draws on existing literature and case studies to provide guidelines for determining optimal stream corridor widths in a watershed located in King County, Washington. 相似文献
77.
Resource suitability: Methods for analyses 总被引:1,自引:0,他引:1
Frederick Steiner 《Environmental management》1983,7(5):401-420
There is a growing need to develop methods for analyzing resource suitability that are both legally defensible and accurate. Three approaches to suitability analysis are reviewed: the US Soil Conservation Service capability classification and important farmlands mapping; the McHarg, or Pennsylvania, suitability analysis method; and Dutch approaches to suitability analysis. Computer applications and the carrying-capacity concept are briefly reviewed. Three applications of suitability analysis are discussed: examples from Medford Township, New Jersey; Whitman County, Washington; and Abuja, the new federal capital city of Nigeria. 相似文献
78.
Use of agricultural land evaluation and site assessment in Whitman County,Washington, USA 总被引:2,自引:0,他引:2
Melanie Tyler Liese Hunter Frederick Steiner Dennis Roe 《Environmental management》1987,11(3):407-412
Whitman County, Washington, USA, one of the largest wheat producing counties in the country, developed a land evaluation and site assessment system for evaluating proposed conversions of agricultural land to heavy commercial uses. The system uses soil potential indices to determine a land evaluation score and a nine-factor site assessment system to weigh suitability for development. Details on each of these are provided along with results for four sample sites.Scientific Paper no. 7165, College of Argiculture and Home Economics Research Paper, Washington State University, Pullman, Washington, project no. 0010. 相似文献
79.
Impact of Length of Dataset on Streamflow Calibration Parameters and Performance of APEX Model 下载免费PDF全文
Amanda M. Nelson Daniel N. Moriasi Mansour Talebizadeh Jean L. Steiner Remegio B. Confesor Prasanna H. Gowda Patrick J. Starks Haile Tadesse 《Journal of the American Water Resources Association》2017,53(5):1164-1177
Due to resource constraints, long‐term monitoring data for calibration and validation of hydrologic and water quality models are rare. As a result, most models are calibrated and, if possible, validated using limited measured data. However, little research has been done to determine the impact of length of available calibration data on model parameterization and performance. The main objective of this study was to evaluate the impact of length of calibration data (LCD) on parameterization and performance of the Agricultural Policy Environmental eXtender model for predicting daily, monthly, and annual streamflow. Long‐term (1984‐2015) measured daily streamflow data from Rock Creek watershed, an agricultural watershed in northern Ohio, were used for this study. Data were divided into five Short (5‐year), two Medium (15‐year), and one Long (25‐year) streamflow calibration data scenarios. All LCD scenarios were calibrated and validated at three time steps: daily, monthly, and annual. Results showed LCD affected the ability of the model to accurately capture temporal variability in simulated streamflow. However, overall average streamflow, water budgets, and crop yields were simulated reasonably well for all LCD scenarios. 相似文献
80.
Banowetz GM Whittaker GW Dierksen KP Azevedo MD Kennedy AC Griffith SM Steiner JJ 《Journal of environmental quality》2006,35(1):133-140
Efforts to improve land-use practices to prevent contamination of surface waters with soil are limited by an inability to identify the primary sources of soil present in these waters. We evaluated the utility of fatty acid methyl ester (FAME) profiles of dry reference soils for multivariate statistical classification of soils collected from surface waters adjacent to agricultural production fields and a wooded riparian zone. Trials that compared approaches to concentrate soil from surface water showed that aluminum sulfate precipitation provided comparable yields to that obtained by vacuum filtration and was more suitable for handling large numbers of samples. Fatty acid methyl ester profiles were developed from reference soils collected from contrasting land uses in different seasons to determine whether specific fatty acids would consistently serve as variables in multivariate statistical analyses to permit reliable classification of soils. We used a Bayesian method and an independent iterative process to select appropriate fatty acids and found that variable selection was strongly impacted by the season during which soil was collected. The apparent seasonal variation in the occurrence of marker fatty acids in FAME profiles from reference soils prevented preparation of a standardized set of variables. Nevertheless, accurate classification of soil in surface water was achieved utilizing fatty acid variables identified in seasonally matched reference soils. Correlation analysis of entire chromatograms and subsequent discriminant analyses utilizing a restricted number of fatty acid variables showed that FAME profiles of soils exposed to the aquatic environment still had utility for classification at least 1 wk after submersion. 相似文献