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891.
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893.
Caught between ongoing habitat destruction and funding shortfalls, conservation organizations are using systematic planning approaches to identify places that offer the highest biodiversity return per dollar invested. However, available tools do not account for the landscape of funding for conservation or quantify the constraints this landscape imposes on conservation outcomes. Using state‐level data on philanthropic giving to and investments in land conservation by a large nonprofit organization, we applied linear regression to evaluate whether the spatial distribution of conservation philanthropy better explained expenditures on conservation than maps of biodiversity priorities, which were derived from a planning process internal to the organization and return on investment (ROI) analyses based on data on species richness, land costs, and existing protected areas. Philanthropic fund raising accounted for considerably more spatial variation in conservation spending (r2 = 0.64) than either of the 2 systematic conservation planning approaches (r2 = 0.08–0.21). We used results of one of the ROI analyses to evaluate whether increases in flexibility to reallocate funding across space provides conservation gains. Small but plausible “tax” increments of 1–10% on states redistributed to the optimal funding allocation from the ROI analysis could result in gains in endemic species protected of 8.5–80.2%. When such increases in spatial flexibility are not possible, conservation organizations should seek to cultivate increased support for conservation in priority locations. We used lagged correlations of giving to and spending by the organization to evaluate whether investments in habitat protection stimulate future giving to conservation. The most common outcome at the state level was that conservation spending quarters correlated significantly and positively with lagged fund raising quarters. In effect, periods of high fund raising for biodiversity followed (rather than preceded) periods of high expenditure on land conservation projects, identifying one mechanism conservation organizations could explore to seed greater activity in priority locations. Our results demonstrate how limitations on the ability of conservation organizations to reallocate their funding across space can impede organizational effectiveness and elucidate ways conservation planning tools could be more useful if they quantified and incorporated these constraints.  相似文献   
894.

Lead (Pb) is a toxic element and environmental pollutant. Pb toxicity and antagonistic effect of selenium (Se) on Pb have been deeply studied in mammals. The testis is one of the target organs of Pb in birds. The aim of this study was to investigate the mitigating effect of Se on Pb toxicity in chicken testes by determining messenger RNA (mRNA) expressions of 5 heat shock proteins (HSPs) and 25 selenoproteins. Sixty male chickens (7-day-old) were randomly divided into the control group, the Se group, the Pb group, and the Pb + Se group, and were fed for 90 days. The feeding methods of chickens were as follows: The control group was fed drinking water and commercial diet (0.49 mg/kg Se). Lead acetate was added into the drinking water (350 mg/L Pb). Sodium selenite was added into the commercial diet (1 mg/kg Se). Multivariate correlation analysis and principal component analysis (PCA) were used to define the relationships among all the measured factors and the most important parameters that could be used as key factors, respectively. The results indicated that Se decreased the increase of mRNA expressions of all the HSPs and increased the decrease of mRNA expressions of all the selenoproteins induced by Pb in the chicken testes. HSP70 may be a biomarker of Pb poisoning in the chicken testes. Se alleviated Pb-induced toxicity in the chicken testes through regulating mRNA expressions of HSPs and selenoproteins.

  相似文献   
895.
Social dominance confers potential advantages in terms of access to superior resources, habitats, and breeding opportunities. In the cooperatively breeding acorn woodpecker (Melanerpes formicivorus), within-brood dominance among juveniles is correlated with relative body size as nestlings. Capitalizing on this relationship, we investigated the fitness consequences of dominance by means of paired comparisons of broodmates. We found that (1) larger fledglings retained at least some of their size advantage as adults; (2) overwinter survival of larger, dominant fledglings was significantly greater than subordinates, but was not relatively greater when resources were poor than when they were good; (3) among birds surviving their first winter, there were no differences vis-à-vis dominance in terms of the proportion of birds acting as helpers or inheriting their natal territory. However, larger, dominant males were present in the study area longer than subordinates, suggesting that they either survived better or were more successful at gaining reproductive opportunities; (4) if only one male broodmate became a helper instead of dispersing, he was significantly more likely to be the smaller subordinate, consistent with the view that helping is a best-of-a-bad-job strategy; and (5) there were no significant differences in reproductive success among pairs of male broodmates that cobred together as adults, consistent with prior work failing to detect a phenotypic correlation of reproductive skew. Our results indicate that within-brood dominance relationships established as juveniles have significant effects on first-year survivorship and at least some aspects of adult fitness.  相似文献   
896.
The concentrations and distributions of some typical chlorinated flame retardants (Dechlorane or Mirex, Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), Dechlorane 604 (Dec 604) and Dechlorane Plus (DP)) and brominated FRs (polybrominated diphenyl ethers (PBDEs), pentabromoethylbenzene (PBEB) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE)) were analyzed in surficial sediment collected from the Dalian coastal area in northeast China. Dec 603, Dec 604, and BTBPE were below their respective limits of detection (LOD) in all sediment samples, while Dechlorane, Dec 602, DP, Σ13BDE (tri- to hepta-BDEs), BDE 209, and PBEB were identified in the ranges <0.015-39.9 ng g(-1) dry weight (dw), <0.011-0.156 ng g(-1) dw, 0.69-7.00 ng g(-1) dw, 0.017-1.33 ng g(-1) dw, 3.94-103 ng g(-1) dw, and <0.073-1.9 ng g(-1) dw, respectively. Relationships between these chlorinated and brominated FRs were analyzed using Pearson's correlation and principal component analysis (PCA). DP, Dechlorane, Σ13BDE, and BDE 209 showed significantly positive correlation (p<0.05), and these relationships showed excellent agreement with PCA results. The spatial trends for Dechlorane, DP, BDE 209, and Σ13BDE showed that high concentrations were found in the industrial zone and lower concentrations in residential and garden zones. The results imply that these FRs are originating from a common source, and support the view that direct input from the effluent of sewage outlets is a major source of these compounds in Dalian sediment.  相似文献   
897.
The distribution, source, ecological risk and ecotoxicity of polycyclic aromatic hydrocarbons (PAHs) of sediments from 7 sampling sites, named as Xinyang (XY), Huainan (HN), Bengbu (BB), Xuyi (XuY), Fuyang (FY), Mengcheng (MC) and Zhengzhou (ZZ), in the Huaihe River basin, China, have been investigated. The total concentrations of 16 USEPA priority PAHs ranged from 62.9 to 2232.4 ng g?1 dry weight (d.w.) with a mean concentration of 1056.8 ng g?1 d.w. Through the assessment of ecological risk, we found that the levels of PAHs in the Huaihe River should not exert adverse biological effects. The total benzo[a]pyrene toxicity equivalent (TEQ) values calculated for samples varied from 0.01 to 194.1 ng g?1 d.w., with an average of 65.9 ng g?1. The toxicity data were accordant with the chemical analysis results in this study. HN, BB and ZZ showed the greatest pollution extent both in the chemical analysis and the study of ecotoxicological effects.  相似文献   
898.

Objective

To estimate the effects of red light camera enforcement on per capita fatal crash rates at intersections with signal lights.

Methods

From the 99 large U.S. cities with more than 200,000 residents in 2008, 14 cities were identified with red light camera enforcement programs for all of 2004-2008 but not at any time during 1992-1996, and 48 cities were identified without camera programs during either period. Analyses compared the citywide per capita rate of fatal red light running crashes and the citywide per capita rate of all fatal crashes at signalized intersections during the two study periods, and rate changes then were compared for cities with and without cameras programs. Poisson regression was used to model crash rates as a function of red light camera enforcement, land area, and population density.

Results

The average annual rate of fatal red light running crashes declined for both study groups, but the decline was larger for cities with red light camera enforcement programs than for cities without camera programs (35% vs. 14%). The average annual rate of all fatal crashes at signalized intersections decreased by 14% for cities with camera programs and increased slightly (2%) for cities without cameras. After controlling for population density and land area, the rate of fatal red light running crashes during 2004-2008 for cities with camera programs was an estimated 24% lower than what would have been expected without cameras. The rate of all fatal crashes at signalized intersections during 2004-2008 for cities with camera programs was an estimated 17% lower than what would have been expected without cameras.

Conclusions

Red light camera enforcement programs were associated with a statistically significant reduction in the citywide rate of fatal red light running crashes and a smaller but still significant reduction in the rate of all fatal crashes at signalized intersections.

Impact on Industry

The study adds to the large body of evidence that red light camera enforcement can prevent the most serious crashes. Communities seeking to reduce crashes at intersections should consider this evidence.  相似文献   
899.
This study describes the relations between different dimensions of leadership commitment, safety climate and attitudes toward change, and how these affect employee perceptions of safety during organizational change in a high risk environment. We collected data from a European national air navigation services provider during a volatile 3-year corporatization process that ended in the sudden collapse of a deliberate change implementation project. Surprisingly, despite visible signs of internal and external stress caused by the volatile and disruptive change process, we did not observe any change in the traditional safety metrics of incident and accident reporting during the study. The study is based on a large survey (n = 422) of individual attitudes and perceptions of safety climate, perception of leadership commitment to safety, attitudes to organizational change, and perception of safety. The data support the claim that perception of safety at least, in part, depends on individual perceptions of the leadership’s commitment to safety, and the safety climate in place at a given point in time. The model shows how employee perceptions of the leadership’s commitment to safety and safety climate are related to both attitudes toward change, and to perceived safety.  相似文献   
900.
In January 1958, a survey of alpine flora was conducted along a recently constructed access road across the upper volcanic slopes of Mauna Loa, Hawaii (2525-3397 m). Only five native Hawaiian species were encountered on sparsely vegetated historic and prehistoric lava flows adjacent to the roadway. A resurvey of roadside flora in 2008 yielded a more than fourfold increase to 22 species, including nine native species not previously recorded. Eight new alien species have now invaded this alpine environment, although exclusively limited to a few individuals in ruderal habitat along the roadway. Alternative explanations for species invasion and altitudinal change over the past 50 years are evaluated: (1) changes related to continuing primary succession on ameliorating (weathering) young lava substrates; (2) local climate change; and (3) road improvements and increased vehicular access which promote enhanced car-borne dispersal of alien species derived from the expanding pool of potential colonizers naturalized on the island in recent decades. Unlike alpine environments in temperate latitudes, the energy component (warming) in climate change on Mauna Loa does not appear to be the unequivocal driver of plant invasion and range extension. Warming may be offset by other climate change factors including rainfall and evapotranspiration.  相似文献   
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