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81.
Alexander M. Kusmanoff Fiona Fidler Ascelin Gordon Georgia E. Garrard Sarah A. Bekessy 《Conservation biology》2020,34(5):1131-1141
Communication and advocacy approaches that influence attitudes and behaviors are key to addressing conservation problems, and the way an issue is framed can affect how people view, judge, and respond to an issue. Responses to conservation interventions can also be influenced by subtle wording changes in statements that may appeal to different values, activate social norms, influence a person's affect or mood, or trigger certain biases, each of which can differently influence the resulting engagement, attitudes, and behavior. We contend that by strategically considering how conservation communications are framed, they can be made more effective with little or no additional cost. Key framing considerations include, emphasizing things that matter to the audience, evoking helpful social norms, reducing psychological distance, leveraging useful biases, and, where practicable, testing messages. These lessons will help communicators think strategically about how to frame messages for greater effect. 相似文献
82.
83.
R. N. Silbiger S. A. Christ A. C. Leonard M. Garg D. L. Lattier S. Dawes P. Dimsoski F. McCormick T. Wessendarp D. A. Gordon A.C. Roth M. K. Smith G. P. Toth 《Environmental monitoring and assessment》1998,51(1-2):481-495
Molecular approaches are particularly useful for measuring genetic diversity and were applied to samples of central stonerollers obtained from sites along tributaries to the Great Miami River in Ohio. We used Random Amplified Polymorphic DNA (RAPD) analysis to assess the level of genetic diversity within and among these populations. RAPD analysis generates genetic profiles that were used to develop indices of genetic similarity. The RAPD method provides a cost effective means of generating an arbitrary sample of anonymous loci across the genome and generate a virtually unlimited set of loci for use in genetic analysis in the absence of specific sequence information. These attributes make RAPDs well suited for use in evaluating the diversity and assessing the potential vulnerability to exposure of populations across multiple spatial scales. The results demonstrate that a significant amount of structuring exists among populations analyzed to date and that a trend exists towards genetic diversity being an inverse function of site distance from the main stem as well as a being directly related to stream order. This indicates that populations farthest from main conduits or in lower order streams, and thereby most isolated, may be the most vulnerable populations to stressor exposure. It is hoped that information pertaining to genetic diversity, when integrated with other metrics of resource condition, will aid in making scientifically grounded decisions on resource management that enhance the probability of population survival and preserve natural evolutionary processes. 相似文献
84.
Paul Scott Paul Brown Julia Verne Jody James Alistair Gordon Joyshri Sarangi Jonathan A. C. Sterne 《Environmental geochemistry and health》2009,31(2):297-308
This ecological study aimed, through the analysis of 1,146 wards in the South West of England (1998–2002), firstly, to examine
whether chemical incidents and public casualties are more likely near complex industry (emissions to land, air or water: Integrated
Pollution Control industry, IPC) or industry with emissions to air only (Local Air Pollution Control industry, LAPC). Secondly,
the study examined whether industry, incidents and casualties are found close to deprivation. Social inequalities were examined
across quintiles of wards. Fifty-two wards (4.5%) contained an IPC industry and 712 (62.1%) an LAPC. Incidents occurred in
132 wards (11.5%), with casualties in 59 (5.1%). Chemical incidents occurred more frequently in wards with LAPC (152, IPC
20); the same was true of casualties (211, 12). With each additional LAPC site in a ward, the risk of an incident rose by
22% (95% confidence interval [CI] 8–38%), suggesting a dose–response relationship. No clear social inequalities were found.
In the South West of England, the public are more likely to be affected by an incident occurring at a simple LAPC site rather
than a complex IPC site. This has implications for emergency planning which, at present, focusses most attention on the larger,
more complex IPC sites. 相似文献
85.
Joy RW Heirigs PL Torgerson GD St Denis M Austin TC Gordon J Tefft B Lindner J 《Journal of the Air & Waste Management Association (1995)》2004,54(3):269-285
A series of studies was performed to develop an alternative to the U.S. Environmental Protection Agency's gold standard IM240 mass-based emission test. The new IM147 test was based on the second phase of the IM240 that consists of 147 sec of transient vehicle operation. Paired IM240/IM147 tests were conducted on vehicles ranging from 1981 to 1996 to determine IM147 cutpoints and excess emissions were identified. Additionally, an optimized test procedure was developed that combined possible triplicate IM147s with improved drive trace quality control, fast-pass, and retest methods. The optimized procedure was found to provide improved vehicle preconditioning with a relatively minor decrease in excess emissions identification. Resulting identification rates ranged from 96 to 100% for hydrocarbons (HC), 93-100% for CO, and 93-100% for NOx, depending on cutpoint selection, while false failures caused by lack of vehicle preconditioning were reduced to essentially zero. Significant vehicle throughput improvements were achieved through the development of software algorithms involving modal fast-pass and retest procedures. Modal drive trace variation limits also were developed to improve test accuracy. The combination of the algorithms reduced average IM147 test times by nearly 60%. 相似文献
86.
Gordon L. Brady 《Environment international》1983,9(5):355-360
The emissions trading program was one of the first major regulatory reform efforts at the U.S. Environmental Protection Agency under the Reagan Administration. This program is a set of guidelines for the states to develop federally approved transactions in discharge permits, called an Emission Reduction Credit. The rules governing emissions trading apply within a total ambient constraint or “pollution budget.” This paper provides a discussion of the emissions trading program as an improved technique for air quality management. The paper begins with a discussion of the concept of emissions trading and how the EPA emissions trading program fits into the U.S. Clean Air Act. It is then argued that emissions trading provides a more cost-effective set of implementation incentives in comparison to a “command and control” regulatory system. A number of important attributes of the emissions trading program are discussed, and estimates of cost reductions are provided. The current status of the implementation of the emissions trading program is discussed. The paper concludes with a discussion of several legal, technical, and administrative obstacles to obtaining the efficiencies of emissions trading. 相似文献
87.
Net photosynthetic O2 evolution by five marine macroalgae:Ulva lactuca L.,Enteromorpha sp.,Ceramium strictum Harvey,Fucus serratus L., andF. vesiculosus L., collected from Danish waters in the summer of 1983 was followed at increasing O2 and with pH either fixed close to pH 7, 8 or 9, or drifting upwards during photosynthesis in a closed chamber to determine the effects of changing O2, pH and DIC (dissolved inorganic carbon) on photosynthesis. Increasing O2, increasing pH and decreasing DIC together limited O2 evolution. Raising the O2 concentration with pH and DIC held constant resulted in less inhibition of net-O2 evolution than when all three factors acted together. The O2 inhibition of photosynthesis was similar to the reported O2 inhibition of ribulose 1,5-bisphosphate carboxylase isolated from lower and higher plants. Net-O2 evolution as a function of the molar ratio of O2 to HCO–
3 + CO2 in solution provided a general, linear relationship (r
2 = 0.72 to 0.84), predicting inhibition of photosynthesis based on O2 pH and DIC changing together. Slopes of this relationship, representing competition between O2 and carbon based on external concentrations, were similar for the five taxonomically different algae, suggesting that similar processes act to reduce net-O2 evolution. 相似文献
88.
The ability of bone char to adsorb three metal ions, namely, copper(II), zinc(II) and cadmium(II) ions from wastewater has been studied. Three single-component equilibrium systems and three binary equilibrium systems have been measured experimentally. The three single-component equilibrium data were analyzed using the Langmuir and the Sips equilibrium isotherm equations. The Sips isotherm gave a better fit of the experimental data than the Langmuir isotherm based on the sum of squares errors (SSE) analysis. The Cu-Zn, Cu-Cd and Cd-Zn binary equilibrium experimental data were examined by incorporating the Langmuir and the Sips isotherm equations into the ideal adsorbed solution theory (IAST). The solution methods and the predicted results for the three binary systems at different metal ion compositions have been evaluated. In addition, the application of the IAST to the model prediction for the fixed bed system is presented. 相似文献
89.
Kinley RD Gordon RJ Stratton GW Patterson GT Hoyle J 《Journal of environmental quality》2007,36(2):469-477
Tile drainage water from agricultural fields commonly exceeds environmental guidelines for phosphorus (P) in rivers and streams. The loss of P through artificial drainage is spatially and temporally variable, and is related to local factors. This study characterizes variability in total P (TP) and soluble reactive P (SRP) concentrations in weekly drainage samples from 39 agricultural fields in Nova Scotia, Canada, from April 2002 through December 2003. We examined connections between P concentrations and the factors: (i) soil texture; (ii) discharge flow rate; (iii) soil test P (STP); (iv) manure type; and (v) crop cover. Generally, variability between fields and samples was great, and fields with standard deviations exceeding the mean for TP, SRP, and flow rate were 71, 54, and 79%, respectively. It was evident that poultry and swine manure contributed to high STPs, and to constantly high TP concentrations with high proportions of SRP. Concentrations varied from week to week, and particularly in April, May, October, and November when the greatest TP, SRP, and flow rate averages were measured. Mean TP concentrations exceed the USEPA (1994) TP guideline of 0.10 mg L(-1) at 82% of the fields, and periodically concentrations more than 10 times, and occasionally more than 50 times higher than the guideline were found. The proportion of SRP in TP had a tendency to be higher when TP levels were high in coarse textured soils. In Nova Scotia, dairy manure is most often applied on permanent cover crops, which did not show as much P concentration variability as crop rotations. Daily or hourly observation of short-term increases in P concentrations related to the described factors would help to characterize the changes in P concentrations observed during frequent heavy drainage flow events. 相似文献
90.
The potential to sequester atmospheric carbon in agricultural and forest soils to offset greenhouse gas emissions has generated interest in measuring changes in soil carbon resulting from changes in land management. However, inherent spatial variability of soil carbon limits the precision of measurement of changes in soil carbon and hence, the ability to detect changes. We analyzed variability of soil carbon by intensively sampling sites under different land management as a step toward developing efficient soil sampling designs. Sites were tilled cropland and a mixed deciduous forest in Tennessee, and old-growth and second-growth coniferous forest in western Washington, USA. Six soil cores within each of three microplots were taken as an initial sample and an additional six cores were taken to simulate resampling. Soil C variability was greater in Washington than in Tennessee, and greater in less disturbed than in more disturbed sites. Using this protocol, our data suggest that differences on the order of 2.0 Mg C ha(-1) could be detected by collection and analysis of cores from at least five (tilled) or two (forest) microplots in Tennessee. More spatial variability in the forested sites in Washington increased the minimum detectable difference, but these systems, consisting of low C content sandy soil with irregularly distributed pockets of organic C in buried logs, are likely to rank among the most spatially heterogeneous of systems. Our results clearly indicate that consistent intramicroplot differences at all sites will enable detection of much more modest changes if the same microplots are resampled. 相似文献