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301.
An ecological perspective on theory, methods, and analysis in environmental psychology: Advances and challenges 总被引:1,自引:1,他引:0
Over the course of environmental psychology's brief history, there has been an interest in ecologically oriented approaches to theory and research. Based on this work, this paper identifies a set of six principles of ecological analysis that present theoretical, methodological, and analytic challenges to future research in environmental psychology. These challenges include the theoretical treatment of the multiple contexts within which human experience and behavior occurs, the need for sampling both persons and environments, the modeling of moderating and mediating processes, the issue of self-selection into and out of different settings, the necessity of considering temporal factors in environmental research, reliance on single methods (e.g., verbal report) in data generation, cross-sectional and longitudinal research designs, and the need for greater use of statistical techniques developed for contextual (multi-level) research. These issues are discussed and illustrated using recent developments in environmentally oriented research. The paper concludes with a set of 11 recommendations for the future. 相似文献
302.
Small-holder farmers often develop adaptable agroforestry management techniques to improve and diversify crop production.
In the cocoa growing region of Ghana, local knowledge on such farm management holds a noteworthy role in the overall farm
development. The documentation and analysis of such knowledge use in cocoa agroforests may afford an applicable framework
to determine mechanisms driving farmer preference and indicators in farm management. This study employed 12 in-depth farmer
interviews regarding variables in farm management as a unit of analysis and utilized cognitive mapping as a qualitative method
of analysis. Our objectives were (1) to illustrate and describe agroforestry management variables and associated farm practices,
(2) to determine the scope of decision making of individual farmers, and (3) to investigate the suitability of cognitive mapping
as a tool for assessing local knowledge use. Results from the cognitive maps revealed an average of 16 ± 3 variables and 19 ± 3
links between management variables in the farmer cognitive maps. Farmer use of advantageous ecological processes was highly
central to farm management (48% of all variables), particularly manipulation of organic matter, shade and food crop establishment,
and maintenance of a tree stratum as the most common, highly linked variables. Over 85% of variables included bidirectional
arrows, interpreted as farm management practices dominated by controllable factors, insofar as farmers indicated an ability
to alter most farm characteristics. Local knowledge use on cocoa production revealed detailed indicators for site evaluation,
thus affecting farm preparation and management. Our findings suggest that amid multisourced information under conditions of
uncertainty, strategies for adaptable agroforestry management should integrate existing and localized management frameworks
and that cognitive mapping provides a tool-based approach to advance such a management support system. 相似文献
303.
Rivera-Rodríguez LB Rodríguez-Estrella R Ellington JJ Evans JJ 《Environmental pollution (Barking, Essex : 1987)》2007,148(2):654-662
A solid phase extraction and gas chromatography with negative chemical ionization mass spectrometry in scan mode (GC-NCI-MS) method was developed to identify and quantify for the first time low levels of organochlorine pesticides (OCs) in plasma samples of less than 100 microl from wild birds. The method detection limits ranged from 0.012 to 0.102 pg/microl and the method reporting limit from 0.036 to 0.307 pg/microl for alpha, gamma, beta and delta-hexachlorocyclohexane (HCH), heptachlor, aldrin, heptachlor epoxide, endosulfan I, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), dieldrin, endrin, endosulfan-II, endrin-aldehyde and endosulfan-sulfate. Pesticide levels in small serum samples from individual Falco sparverius, Sturnella neglecta, Mimus polyglottos and Columbina passerina were quantified. Concentrations ranged from not detected (n/d) to 204.9 pg/microl for some OC pesticides. All levels in the food web in and around cultivated areas showed the presence of pesticides notwithstanding the small areas for agriculture existing in the desert of Baja California peninsula. 相似文献
304.
Daniel M. Evans Stephen H. Schoenholtz Parker J. Wigington Jr Stephen M. Griffith William C. Floyd 《Environmental monitoring and assessment》2014,186(2):873-887
Research on relationships between dissolved nutrients and land-use at the watershed scale is a high priority for protecting surface water quality. We measured dissolved nitrogen (DN) and ortho-phosphorus (P) along 130 km of the Calapooia River (Oregon, USA) and 44 of its sub-basins for 3 years to test for associations with land-use. Nutrient concentrations were analyzed for spatial and seasonal patterns and for relationships with land-use and stream discharge. Ortho-P and DN were higher in lower-elevation sub-basins dominated by poorly drained soils and agricultural production compared with higher-elevation sub-basins dominated by well-drained soils and forests. Eight lower basins had at least one sample period with nitrate-N?>?10 mg L?1. The Calapooia River had lower concentrations of dissolved nutrients compared with lower sub-basins, often by an order of magnitude. Dissolved organic N represented a greater proportion of DN in the upper forested sub-basins. Seasonal nutrient concentrations had strong positive correlations to the percent of a sub-basin that was managed for agriculture in all seasons (p?values?≤?0.019) except summer. Results suggest that agricultural lands are contributing to stream nutrient concentrations. However, poorly drained soils in agricultural areas may also contribute to the strong relationships that we found between dissolved nutrients and agriculture. 相似文献
305.
Daniel M. Evans C. Andrew Dolloff W. Michael Aust Amy M. Villamagna 《Journal of the American Water Resources Association》2012,48(2):266-276
Evans, Daniel M., C. Andrew Dolloff, W. Michael Aust, and Amy M. Villamagna, 2012. Effects of Eastern Hemlock Decline on Large Wood Loads in Streams of the Appalachian Mountains. Journal of the American Water Resources Association (JAWRA) 48(2): 266‐276. DOI: 10.1111/j.1752‐1688.2011.00610.x Abstract: Eastern hemlock (Tsuga canadensis), a foundation species important to riparian forests of the Appalachian Mountains, is in decline due to the hemlock woolly adelgid (HWA) (Adelges tsugae). The effect of this insect on large wood (LW) production and recruitment to streams is largely unknown. We measured LW load, riparian forest composition, and T. canadensis health in 47 streams from Maine to Alabama and developed a conceptual model that frames the expected forest stand and instream LW response to the disturbance caused by HWA. In stands with HWA, 24.3% of the overstory T. canadensis basal area was stressed and 7.5% was dead, whereas only 3.0% was stressed and 2.0% was dead in stands without HWA. Mean T. canadensis effective LW load was 0.20 m3/100 m2 in streams with adjacent stands infested by HWA, almost three times higher than in streams flowing through uninfested stands (p = 0.048). Higher frequencies of LW were found at streams with HWA present and there was a positive association between the percent of dead T. canadensis and T. canadensis LW load (ρ = 0.4468; p = <0.0001). Greater total LW loads were associated with higher stream gradients, lesser bankfull widths, and streams at lower latitudes. Our research supports the hypothesis that HWA infestation of T. canadensis in riparian forest stands has increased LW loads in streams. This episodic disturbance to the riparian forest overstory may have lasting impacts on aquatic ecosystem structure and function. 相似文献
306.
Suzannah Evans Comfort Joe Bob Hester 《Environmental Communication: A Journal of Nature and Culture》2019,13(3):281-286
Studies show that NGOs persist in using social media to impart unidirectional messages rather than taking advantage of the participatory nature of networked media. Fear of a loss of message control may be at the heart of NGOs’ desire to keep social media messages on track. The current study examines the success of an environmental NGO in keeping its social media messages under control using quantitative content analysis of an NGO-promoted hashtag, #climatemarch, during a United Nations conference on climate change in 2015. Three dimensions of social media message success – volume, topic/valence, and participants – are proposed. 相似文献
307.
John S. Evans Douglas W. Cooper 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1298-1303
Open sources are those stationary sources of air pollution too great in extent to be controlled through enclosure or ducting. Open sources of atmospheric particles include: wind erosion, tilling, and prescribed burning of agricultural cropland; surface mining and wind erosion of tailings piles; vehicular travel on both paved and unpaved roads; construction site activity; and forest fires. It is estimated that in 1976 the total open source emissions of particles in the U.S. amounted to over 580 × 106 ton. These estimates indicate that emissions from the two largest open source classes, travel on unpaved roads and agricultural wind erosion, accounted for 86% of this total. The open source emissions in ten states (AZ, CA, KS, MN, MT, NM, ND, OH, SD, TX) contributed 6 2% of the national emissions for 1976. 相似文献
308.
Gordon M. Evans 《Journal of the Air & Waste Management Association (1995)》2013,63(7):1047-1051
Among the objectives of the EPA’s Superfund Innovative Technology Evaluation (SITE) Program are two which pertain to the issue of economics: 1. That the program will provide a projected cost for each treatment technology demonstrated. 2. That the program will attempt to identify and remove impediments to the development and commercial use of alternative technologies.1 The SITE Program has fostered a special relationship between elements of the public and private sector. In turn, this has created a unique set of problems. These problems are most apparent where objectives of the public and private sector conflict, as in the area of cost economics. One concern of the SITE Program is to provide the public with an impartial analysis of each technology’s cost. Just as important is the need to be sensitive to the demands of the competitive economic environment which face every firm selling innovative technology (especially when the goal is to promote the commercial use of new technologies). An early concern of the SITE Program was to design a methodology for projecting and reporting costs which tried to balance the needs of these two groups. Toward this end, four issues were identified which were thought to have a significant impact on the SITE Program's ability to generate useful cost projections. An analysis of these issues led to the creation of a simple five-part cost methodology. This paper will review the nature of these problems and will describe the methodology which addresses them. Finally, a review of cost data gathered from the first nine demonstrations will be presented. 相似文献
309.
J.S. Evans K.M. Thompson D. Hattis 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1700-1703
ABSTRACT Standard approaches for computing population exposures due to specific sources of air pollutants are relatively complex. In many cases, more simple and approximate methods would be useful. This paper develops an approach, based on the concept of exposure efficiency, that may be used for estimating the impact of a source (or source class) on the integrated population exposure. The approach is illustrated by an example, which uses the concept of exposure efficiency to examine the impact of perchloroeth-ylene emissions from dry cleaners in the United States. The paper explores the geographic variability of exposure efficiency by evaluating it for each of 100 randomly selected dry cleaners. For perchloroethylene, which has a long atmospheric residence time, the site-to-site variability in exposure efficiency is found to be relatively small. This suggests that simple exposure assessments, based on generic distributional characterizations of exposure efficiency, may be used in risk assessments without introducing appreciable uncertainty. For many compounds, like perchloroethylene, the uncertainty inherent in the estimation of cancer potency or source emissions would dominate these small errors. 相似文献
310.