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881.
In the current regulatory climate, environmental professionals are becoming increasingly involved with a side of the business that has often been given low priority in the past: communicating with the public about environmental and health risk issues. This article describes effective approaches to such communication, and demonstrates their implementation success. 相似文献
882.
Stephen R. Kessell Meredith W. Potter Collin D. Bevins Larry Bradshaw Bruhe W. Jeske 《Environmental management》1978,2(4):347-363
Recent advances in fire modeling permit quantitative estimations of fire behavior from quantitative inputs that describe the fuel array and conditions, such as weather and site data, under which it will burn. This paper describes the collection, analysis, and stratification of flammable forest fuels data for coniferous forest ecosystems in Montana and then illustrates the resource management application of these data in three areas: the development of the fire behavior model, a determination of the model's sensitivity to input errors as reflected by fire behavior prediction errors, and the development of a fire hazard simulator (TAROT). A new integrated stand simulator, GANDALF, is highlighted.Conclusions center on the need to integrate fire management into the land management planning decision-making process.This work was supported by a USDI National Park Service contract to Gradient Modeling, Inc., a nonprofit research foundation devoted to ecologic research and resource management applications, and by cooperative aid agreements between Gradient Modeling, Inc. and the USDA Forest Service, Intermountain Forest and Range Experiment Station, Northern Forest Fire Laboratory (Fire in Multiple Use Management, R, D, and A Program). 相似文献
883.
Stephen R. Kessell 《Environmental management》1979,3(1):29-40
The application of vegetation information to resource management problems is reviewed in four areas: (1) the stratification of vegetation data by classification and gradient analysis, (2) the storage and retrieval of these data, (3) the sources of vegetation information, and (4) the accuracy and resolution requirements posed by different management applications. Conclusions indicate that the successful application of inference methods to resource management problems requires an appropriate integration of these four components. 相似文献
884.
One of the enduring facts of the human condition is that the earth's resources are finite and its environment fragile. It is also evident that human behavior is rarely based on an appreciation of these facts. While the outlook may be bleak, so are some of the proposed solutions. Reasonable people have suggested that, to survive, an environmentally enlightened authoritarian government must be adopted. This article suggests that such a solution is unworkable, in part because it fails to consider critical aspects of human nature. A framework is proposed for developing solutions compatible with human capabilities. 相似文献
885.
A total of 25 scenes representing the five visual quality objectives in the US Department of Agriculture Forest Service visual management system were presented to 18 professional and public interest groups in western Montana. The results indicate that nearly all the groups have similar rank orderings of the scenes in terms of visual preference. However, the groups differ according to the absolute values of their ratings. Most groups were unable, in a statistical sense, to differentiate the scenic quality of areas in the preservation and retention visual quality objectives. Landscape architects tended to rate scenes in a way similar to professional forest management groups. 相似文献
886.
The effects of off-road vehicles (ORVs) on the dune system of Fire Island National Seashore, New York, USA, were examined through a detailed, two-year field study. The experimental approach was adopted in order to evaluate the environmental effects of ORVs in this zone. Adjacent control and impact sites were established in two locations. Vehicle impacts were applied at the equivalent rate of one vehicle pass per week. Monitoring of foredune vegetation through sequential quadrat surveys and construction of sea-ward limit maps showed a significant loss of vegetation resulting from ORV impacting. Loss of vegetation resulted in an alteration of the natural foredune profile, which could increase dune erosion during storm wave attack. 相似文献
887.
Steven W. Effler Carol M. Brooks Mary Gail Perkins Michael Meyer Stephen D. Field 《Journal of the American Water Resources Association》1987,23(6):1193-1201
ABSTRACT: The underwater light field of eight central New York lakes, which represent a wide range of trophic state, was characterized through paired measurements of Sechi disc transparency (SD, m) and diffuse light attenuation (Kd, m?1). A total of 90 paired measurements are included in the data base. Substantial variability in the Kd SD product with time within individual systems, and amongst systems, was observed, which indicates differences in the relative contributions of absorption and scattering to attenuation. More than 50 percent of the temporal variability in Kd was attributable to attendant variations in chlorophyll a (C, mg m?3) in only two of the lakes. Estimates of the adsorption (a, m?1) and scattering (b, m?1) coefficients based on paired Kd and SD measurements compared well with more precise determinations available for one of the lakes. Determinations of a and b for the eight lakes, from SD and Kd measurements, indicated great system-specificity and temporal variability in these characteristics. The temporal variability in relative contributions of a and b to Kd is consistent with covariation of different attenuating components and the lack of correlation between C and Kd in most of the study lakes. 相似文献
888.
Gyamfi Bright Akwasi Bekun Festus Victor Balsalobre-Lorente Daniel ONIFADE Stephen Taiwo Ampomah Asiedu Benjamin 《Environment, Development and Sustainability》2022,24(10):11852-11870
Environment, Development and Sustainability - This study is motivated by the United Nations Sustainable Development Goals (UN-SDG-7,8,11,12 and 13) on the need for clean and responsible energy... 相似文献
889.
Hydrological,Physical, and Chemical Functions and Connectivity of Non‐Floodplain Wetlands to Downstream Waters: A Review
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Charles R. Lane Scott G. Leibowitz Bradley C. Autrey Stephen D. LeDuc Laurie C. Alexander 《Journal of the American Water Resources Association》2018,54(2):346-371
We reviewed the scientific literature on non‐floodplain wetlands (NFWs), freshwater wetlands typically located distal to riparian and floodplain systems, to determine hydrological, physical, and chemical functioning and stream and river network connectivity. We assayed the literature for source, sink, lag, and transformation functions, as well as factors affecting connectivity. We determined NFWs are important landscape components, hydrologically, physically, and chemically affecting downstream aquatic systems. NFWs are hydrologic and chemical sources for other waters, hydrologically connecting across long distances and contributing compounds such as methylated mercury and dissolved organic matter. NFWs reduced flood peaks and maintained baseflows in stream and river networks through hydrologic lag and sink functions, and sequestered or assimilated substantial nutrient inputs through chemical sink and transformative functions. Landscape‐scale connectivity of NFWs affects water and material fluxes to downstream river networks, substantially modifying the characteristics and function of downstream waters. Many factors determine the effects of NFW hydrological, physical, and chemical functions on downstream systems, and additional research quantifying these factors and impacts is warranted. We conclude NFWs are hydrologically, chemically, and physically interconnected with stream and river networks though this connectivity varies in frequency, duration, magnitude, and timing. 相似文献
890.
Hydrogeomorphic Reference Condition and Its Relationship with Macroinvertebrate Assemblages in Southeastern U.S. Sand Hills Streams
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Stephen A. Sefick Ely Kosnicki Michael H. Paller Jack W. Feminella 《Journal of the American Water Resources Association》2018,54(4):914-933
Defining stream reference conditions is integral to providing benchmarks to ecological perturbation. We quantified channel geometry, hydrologic and environmental variables, and macroinvertebrates in 62 low‐gradient, SE United States (U.S.) Sand Hills (Level IV ecoregion) sand‐bed streams. To identify hydrogeomorphic reference condition (HGM), we clustered channel geometry deviation from expectations given watershed area (Aws), resulting in two HGM groups discriminated by area at the top of bank (Atob) residuals <0.6 m2 and >0.6 m2 predicted to be HGM reference/nonreference streams, respectively. Two independent partial least squares discriminate analyses used (1) hydrologic/environmental variables and (2) macroinvertebrate mean trait values (mT) on 10 reference/nonreference stream pairs of similar Aws for classification validation. Nonreference streams had flashier hydrographs and altered flow magnitudes, lower organic matter, coarser substrate, higher pH/specific conductivity compared with reference streams. Macroinvertebrate assemblages corresponded to HGM groupings, with mT indicative of multivoltinism, collector‐gatherer functional feeding groups, fast current‐preference taxa, and lower Ephemeroptera, Plecoptera, and Trichoptera richness and biotic integrity in nonreference streams. HGM classifications in Sand Hills, sand‐bed streams were determined from channel geometry. This easily implemented classification is indicative of contemporary hydrologic disturbance resulting in contrasting macroinvertebrate assemblages. 相似文献