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221.
The influence of place attachment, and moral and normative concerns on the conservation of native vegetation: A test of two behavioural models 总被引:1,自引:0,他引:1
Christopher M. Raymond Gregory Brown Guy M. Robinson 《Journal of environmental psychology》2011,31(4):323-335
This study examines the influence of place attachment, values, beliefs and personal norms about environmental action on the conservation of native vegetation in two primary production settings in South Australia. We use regression and multiple mediation analyses to test a base model of pro-environmental behaviour which includes variables from value-belief-norm (VBN) theory and then compare it to an expanded model which includes the same variables and five dimensions of place attachment. The expanded model including place attachment explained up to twice the amount of variance in native vegetation planting than the base model when controlling for all variables preceding behaviour, but the overall explanatory power was low (<22%). Place attachment had a stronger influence on the antecedents of behaviour compared with the behaviour itself, particularly nature bonding which was a significant moderate predictor of both personal norms and awareness of consequences in the two study regions. We assert that place attachment has statistically significant direct and indirect effects on variables included in VBN theory. Future studies may reveal stronger effects in settings where there are fewer resource and monetary costs associated with pro-environmental behaviour. 相似文献
222.
223.
Kellner JR Asner GP Kinney KM Loarie SR Knapp DE Kennedy-Bowdoin T Questad EJ Cordell S Thaxton JM 《Ecological applications》2011,21(6):2094-2104
Escape from natural enemies is a widely held generalization for the success of exotic plants. We conducted a large-scale experiment in Hawaii (USA) to quantify impacts of ungulate removal on plant growth and performance, and to test whether elimination of an exotic generalist herbivore facilitated exotic success. Assessment of impacted and control sites before and after ungulate exclusion using airborne imaging spectroscopy and LiDAR, time series satellite observations, and ground-based field studies over nine years indicated that removal of generalist herbivores facilitated exotic success, but the abundance of native species was unchanged. Vegetation cover <1 m in height increased in ungulate-free areas from 48.7% +/- 1.5% to 74.3% +/- 1.8% over 8.4 years, corresponding to an annualized growth rate of lambda = 1.05 +/- 0.01 yr(-1) (median +/- SD). Most of the change was attributable to exotic plant species, which increased from 24.4% +/- 1.4% to 49.1% +/- 2.0%, (lambda = 1.08 +/- 0.01 yr(-1)). Native plants experienced no significant change in cover (23.0% +/- 1.3% to 24.2% +/- 1.8%, lambda = 1.01 +/- 0.01 yr(-1)). Time series of satellite phenology were indistinguishable between the treatment and a 3.0-km2 control site for four years prior to ungulate removal, but they diverged immediately following exclusion of ungulates. Comparison of monthly EVI means before and after ungulate exclusion and between the managed and control areas indicates that EVI strongly increased in the managed area after ungulate exclusion. Field studies and airborne analyses show that the dominant invader was Senecio madagascariensis, an invasive annual forb that increased from < 0.01% to 14.7% fractional cover in ungulate-free areas (lambda = 1.89 +/- 0.34 yr(-1)), but which was nearly absent from the control site. A combination of canopy LAI, water, and fractional cover were expressed in satellite EVI time series and indicate that the invaded region maintained greenness during drought conditions. These findings demonstrate that enemy release from generalist herbivores can facilitate exotic success and suggest a plausible mechanism by which invasion occurred. They also show how novel remote-sensing technology can be integrated with conservation and management to help address exotic plant invasions. 相似文献
224.
Edna González-Bernal Gregory P. Brown Elisa Cabrera-Guzmán Richard Shine 《Behavioral ecology and sociobiology》2011,65(7):1367-1375
The foraging sites selected by an ambush forager can strongly affect its feeding opportunities. Foraging cane toads (Rhinella marina) typically select open areas, often under artificial lights that attract insects. We conducted experimental trials in the
field, using rubber mats placed under lights, to explore the influence of substrate color and rugosity on prey availability
(numbers, sizes, and types of insects) and toad foraging success. A mat's color (black vs. white) and rugosity (smooth vs.
rough) did not influence the numbers, sizes, or kinds of insects that were attracted to it, but toads actively preferred to
feed on rugose white mats (50% of prey-capture events, vs. a null of 25%). White backgrounds provided better visual contrast
of the (mostly dark) insects, and manipulations of prey color in the laboratory showed that contrast was critical in toad
foraging success. Insects landing on rugose backgrounds were slower to leave, again increasing capture opportunities for toads.
Thus, cane toads actively select backgrounds that maximize prey-capture opportunities, a bias driven by the ways that substrate
attributes influence ease of prey detection and capture rather than by absolute prey densities. 相似文献
225.
Temporal variability of forest fires in eastern Amazonia 总被引:1,自引:0,他引:1
Widespread occurrence of fires in Amazonian forests is known to be associated with extreme droughts, but historical data on the location and extent of forest fires are fundamental to determining the degree to which climate conditions and droughts have affected fire occurrence in the region. We used remote sensing to derive a 23-year time series of annual landscape-level burn scars in a fragmented forest of the eastern Amazon. Our burn scar data set is based on a new routine developed for the Carnegie Landsat Analysis System (CLAS), called CLAS-BURN, to calculate a physically based burn scar index (BSI) with an overall accuracy of 93% (Kappa coefficient 0.84). This index uses sub-pixel cover fractions of photosynthetic vegetation, non-photosynthetic vegetation, and shade/burn scar spectral end members. From 23 consecutive Landsat images processed with the CLAS-BURN algorithm, we quantified fire frequencies, the variation in fire return intervals, and rates of conversion of burned forest to other land uses in a 32 400 km2 area. From 1983 to 2007, 15% of the forest burned; 38% of these burned forests were subsequently deforested, representing 19% of the area cleared during the period of observation. While 72% of the fire-affected forest burned only once during the 23-year study period, 20% burned twice, 6% burned three times, and 2% burned four or more times, with the maximum of seven times. These frequencies suggest that the current fire return interval is 5-11 times more frequent than the estimated natural fire regime. Our results also quantify the substantial influence of climate and extreme droughts caused by a strong El Ni?o Southern Oscillation (ENSO) on the extent and likelihood of returning forest fires mainly in fragmented landscapes. These results are an important indication of the role of future warmer climate and deforestation in enhancing emissions from more frequently burned forests in the Amazon. 相似文献
226.
Gregory Z. Bedny Waldemar Karwowski Mark H. Seglin 《International journal of occupational safety and ergonomics》2013,19(2):121-133
This paper describes a hear-rate methodology to determine the cost-effectiveness of an ergonomics intervention to reduce workload and improve working conditions. This is a practical approach as opposed to the energy expenditure technique that is difficult to implement in natural settings. This was a laboratory study using a large excavator cabin with devices to simulate excavation operations. Mean heart rate was used to calculate the required rest time during a shift with or without air-conditioning. The criterion for evaluation was differences in required rest time during a shift under these 2 conditions. The simplicity and objectivity of this approach invites use to solve the problem of the economic evaluation of ergonomics interventions. 相似文献
227.
The effects of boat propeller scarring intensity on nekton abundance in subtropical seagrass meadows
Seagrasses play a critical role in the function and structure of coastal ecosystems, and they are an important habitat for
a variety of marine organisms. Damage to seagrass beds caused by boat propeller scarring is significant in many areas. This
study was designed to assess the impact of varying scarring intensities on nekton density. We selected ten replicate (10 m×25 m
quadrats) sites representing four distinct scarring intensities: reference (0%), low (5% or less), moderate (5–15%), and severe
(>15%). Sites were sampled in 2003–2004 for nekton during four seasons (summer, fall, winter, and spring) using epibenthic
sleds. There were eight taxa numerically dominant in all seasons and an additional four seasonally dominant species. We were
unable to detect a significant effect of propeller scarring on nekton density at any scarring level. Additionally, regression
analysis indicated no relationship between scarring intensity and nekton density. These results suggest that propeller scarring
intensities of up to ca. 27% may not impact nekton densities. However, seagrass loss, higher scarring intensity, and scale
may play a critical role in determining the impact of propeller scarring on nekton. 相似文献
228.
Myron Charles Baker Gregory L. Sherman Tad C. Theimer Dana C. Bradley 《Behavioral ecology and sociobiology》1982,11(2):133-137
Summary A field study of the ranging behavior of post-fledging White-crowned Sparrows (Zonotrichia leucophrys nuttalli) was carried out in undisturbed natural habitat in the Point Reyes National Seashore, Marin Co., California, USA. Forty-three first-brood juveniles, with tail feathers still growing, were banded at an estimated average age of 27 days and re-trapped an average of an additional 24 days for a total minimum time in residence in the immediate natal area of 51 days (Table 1).The distance from the site of first capture to subsequent recapture sites was about 60 m until age 35 days; then the distance increased to about 250 m by age 50 days (Fig. 2). These data indicate that the average juvenile White-crowned Sparrow completes at least the first 50 days of life in its natal area. Experimental work on song ontogeny has previously demonstrated that the sensitive period for song learning ends at about 50 days. Hence, young in our study population probably learn their natal dialect prior to any major dispersal movements. The correspondence between residence time and song learning would have the consequence of perpetuating song dialects as geographically structured populations. 相似文献
229.
230.
In 2006 the Massachusetts Toxics Use Reduction Institute conducted a study to determine if states could identify safer alternatives to five chemicals of concern. The chemicals investigated included di (2-ethylhexyl) phthalate (DEHP), formaldehyde, hexavalent chromium, lead and perchloroethylene. First, the Institute developed a methodology for assessing alternatives to these five chemicals that allowed it to quickly determine priority uses and alternatives to assess and to research the pertinent decision criteria, which included performance, technical, financial environmental and human health parameters. The methodology included important feedback from stakeholders in the state, which helped to focus and enhance the value of the work. Second, the Institute implemented the methodology over a ten month period. Based on the activities conducted by the Institute, safer alternatives were identified for each of the priority uses associated with the five chemicals studied. This report summarizes the methodology employed and provides examples of the results for one of the five chemicals, namely DEHP. The experience of the Institute and the information contained in this report indicates that alternatives assessment was a useful approach to organizing and evaluating information about chemicals and alternatives. 相似文献