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191.
Indigenous peoples are often considered potential allies in the conservation of biological diversity. Here we assess whether ethnobotanical skills of indigenous people contribute to a reduction in the clearance of tropical rain forest. We measured ethnobotanical skills of male household heads and area of rain forest cleared for agriculture among 128 households of Tsimane', a native Amazonian group in Bolivia. We used multivariate regressions to estimate the relation between ethnobotanical skills and area of rain forest cleared while controlling for schooling, health status, number of plots cleared, adults in household, and village of residency. We found that when the ethnobotanical skills of the male household head were doubled, the amount of tropical rain forest cleared per household was reduced by 25%. The association was stronger when the area of old-growth forest cleared was used as the dependent variable than when the area cleared from fallow forest was used as the dependent variable. People who use the forest for subsistence might place a higher value on standing forest than people who do not use it, and thus they may be more reluctant to cut down the forest. 相似文献
192.
193.
Rubenstein LS 《Disasters》2011,35(4):680-700
Despite increasing experience in health reconstruction in societies emerging from conflict, the policy basis for investing in the development of equitable and effective health systems in the wake of war remains unsettled. Consideration of post-conflict health reconstruction is almost entirely absent in donor policies on global health. Practically by default, health programmes are seen increasingly as an element of stabilisation and security interventions in the aftermath of armed conflict. That perspective, however, lacks an evidence base and can skew health programmes towards short-term security and stabilisation goals that have a marginal impact and violate the principles of equity, non-discrimination, and quality, which are central to sound health systems and public acceptance of them. A better approach is to ground policy in legitimacy, viewing health both as a core social institution and one that, if developed according to human rights principles, including equity, non-discrimination, participation and accountability, can advance the effectiveness and the quality of governance in the emerging state. 相似文献
194.
Olga N. Krankina Dominick A. DellaSala Jessica Leonard Mikhail Yatskov 《Environmental management》2014,54(1):112-121
To examine ownership and protection status of forests with high-biomass stores (>200 Mg/ha) in the Pacific Northwest (PNW) region of the United States, we used the latest versions of publicly available datasets. Overlay, aggregation, and GIS-based computation of forest area in broad biomass classes in the PNW showed that the National Forests contained the largest area of high-biomass forests (48.4 % of regional total), but the area of high-biomass forest on private lands was important as well (22.8 %). Between 2000 and 2008, the loss of high-biomass forests to fire on the National Forests was 7.6 % (236,000 ha), while the loss of high-biomass forest to logging on private lands (364,000 ha) exceeded the losses to fire across all ownerships. Many remaining high-biomass forest stands are vulnerable to future harvest as only 20 % are strictly protected from logging, while 26 % are not protected at all. The level of protection for high-biomass forests varies by state, for example, 31 % of all high-biomass federal forests in Washington are in high-protection status compared to only 9 % in Oregon. Across the conterminous US, high-biomass forest covers <3 % of all forest land and the PNW region holds 56.8 % of this area or 5.87 million ha. Forests with high-biomass stores are important to document and monitor as they are scarce, often threatened by harvest and development, and their disturbance including timber harvest results in net C losses to the atmosphere that can take a new generation of trees many decades or centuries to offset. 相似文献
195.
Shanwei Xu Tim Reuter Brandon H. Gilroyed Lisa Tymensen Yongxin Hao Xiying Hao Miodrag Belosevic Jerry J. Leonard Tim A. McAllister 《Waste management (New York, N.Y.)》2013,33(6):1372-1380
Provided that infectious prions (PrPSc) are inactivated, composting of specified risk material (SRM) may be a viable alternative to rendering and landfilling. In this study, bacterial and fungal communities as well as greenhouse gas emissions associated with the degradation of SRM were examined in laboratory composters over two 14 day composting cycles. Chicken feathers were mixed into compost to enrich for microbial communities involved in the degradation of keratin and other recalcitrant proteins such as prions. Feathers altered the composition of bacterial and fungal communities primarily during the first cycle. The bacterial genera Saccharomonospora, Thermobifida, Thermoactinomycetaceae, Thiohalospira, Pseudomonas, Actinomadura, and Enterobacter, and the fungal genera Dothideomycetes, Cladosporium, Chaetomium, and Trichaptum were identified as candidates involved in SRM degradation. Feathers increased (P < 0.05) headspace concentrations of CH4 primarily during the early stages of the first cycle and N2O during the second. Although inclusion of feathers in compost increases greenhouse gas emissions, it may promote the establishment of microbial communities that are more adept at degrading SRM and recalcitrant proteins such as keratin and PrPSc. 相似文献
196.
Krista J. Patriquin Marty L. Leonard Hugh G. Broders Colin J. Garroway 《Behavioral ecology and sociobiology》2010,64(6):899-913
Social structure, which is a function of the patterns of interactions among individuals, is particularly variable in fission–fusion
societies. The underlying factors that drive this variation are poorly understood. Female northern long-eared bats (Myotis septentrionalis) live in fission–fusion societies where females form preferred associations within groups that vary daily in size and composition
as individuals switch roosts. The goal of our study was to test the predictions that preferred associations and social networks
of female northern long-eared bats vary with reproductive period and age. We also tested the prediction that preferred relationships
persist across years despite movements from summer roosts to winter hibernacula. Network analyses revealed that during gestation,
females roosted in smaller groups where they roosted more regularly with fewer individuals than during lactation. This variation
may reflect different social strategies to mediate higher energetic costs during lactation. Females of all ages roosted more
often with younger individuals, which in turn had more direct and indirect associations than all other age classes. Younger
individuals may play a role in maintaining connections between individuals, perhaps as a result of younger individuals being
more exploratory. Temporal analyses suggested that relationships can persist for years as some pairs roosted together for
multiple summers. We suggest that the dynamic nature of fission–fusion societies is associated with individual strategies
to increase fitness relative to individual characteristics, in this case reproductive condition and age. 相似文献
197.
Seigneur C Lohman K Vijayaraghavan K Jansen J Levin L 《Journal of the Air & Waste Management Association (1995)》2006,56(6):743-751
Two mathematical models of the atmospheric fate and transport of mercury (Hg), an Eulerian grid-based model and a Gaussian plume model, are used to calculate the atmospheric deposition of Hg in the vicinity (i.e., within 50 km) of five coal-fired power plants. The former is applied using two different horizontal resolutions: coarse (84 km) and fine (16.7 km). More than 96% of the power plant Hg emissions are calculated with the plume model to be transported beyond 50 km from the plants. The grid-based model predicts a lower fraction to be transported beyond 50 km: >91% with a coarse resolution and >95% with a fine resolution. The contribution of the power plant emissions to total Hg deposition within a radius of 50 km from the plants is calculated to be <8% with the plume model, <14% with the Eulerian model with a coarse resolution, and <10% with the Eulerian model with a fine resolution. The Eulerian grid-based model predicts greater local impacts than the plume model because of artificially enhanced vertical dispersion; the former predicts about twice as much Hg deposition as the latter when the area considered is commensurate with the resolution of the grid-based model. If one compares the local impacts for an area that is significantly less than the grid-based model resolution, then the grid-based model may predict lower local deposition than the plume model, because two compensating errors affect the results obtained with the grid-based model: initial dilution of the power plant emissions within one or more grid cells and enhanced vertical mixing to the ground. 相似文献
198.
Gregory Sauter Kathleen Leonard 《Journal of the American Water Resources Association》1997,33(1):155-162
ABSTRACT: Constructed wetlands have recently gained popularity as an alternative method for wastewater treatment. This paper compares two design methodologies currently used for constructed wetlands; Tennessee Valley Authority (TVA) and the Environmental Protection Agency (EPA) methods. A discussion of parameters for both methods is given and a wetland treatment system is designed for an individual residence with typical BOD5 loads and flow rates. Calculation results revealed significant discrepancies in the required constructed wetlands volume, and thus detention time, stemming from inherent differences in the design methodologies. The EPA method relies heavily on plug flow kinetics, and is therefore sensitive to changes in the reaction rate constant and media porosity. Conversely, TVA determines the surface area by sizing in accordance with a recommended hydraulic loading criterion and is affected only by the hydraulic flow rates. This study concluded that a constructed wetland is a viable option under design considerations that are not favorable for traditional on-site wastewater treatment methods. However, it is recommended that conservative values for flow and loading rates be assumed to assure complete treatment for either of the design methods. 相似文献
199.
Charles T. Schick Leonard A. Brennan Joseph B. Buchanan Michael A. Finger Tod M. Johnson Steven G. Herman 《Environmental monitoring and assessment》1987,9(2):115-131
Arctic-breeding shorebirds collected in western Washington state during winter and spring, and a comparative sample collected in coastal California during the winter were analyzed for organochlorine contaminants to determine the potential impact of these residues on populations of peregrine falcons (Falco peregrinus) and merlins (F. columbarius) which prey upon shorebirds in western Washington. Dunlins (Calidris alpina), an important winter prey for falcons in western Washington, were collected between 1975 and 1981. During winter 1980–81, dunlins carried low organochlorine residues; DDE levels ranged from 0.01 to 1.2 ppm, and PCB levels ranged from 0.02 to 0.82 ppm (wet weight). Levels of other organochlorine contaminants (HCB, Chlordane compounds, Dieldrin, and Heptachlor Epoxide), analyzed in a subsample of dunlins, were consistently lower than DDE and PCB levels, and ranged from 0.001 to 0.22 ppm (wet weight). Dunlins in western Washington did not significantly increase their DDE or PCB burdens over the 1980–81 winter. A decline in DDE residues between 1978 and 1981 was noted, and declines in PCB residues from both 1975 and 1978 to 1980–81 were noted. Residues in other wintering shorebirds from western Washington were similar. Wintering sanderlings (Calidris alba) from California, revealed much higher DDE contamination than in Washington (up to 32 ppm, wet weight). Spring migrant shorebirds in western Washington contained both low and very high DDE residues (up to 417 ppm, wet weight). There is evidence suggesting these high DDE concentrations are accumulated along the Pacific coast of North America. 相似文献
200.
This study examined the relationship of specific religions and degree of religious beliefs to various job-related attitudes and values such as motivational needs, job satisfaction, work ethic, and work, job and organizational commitment. Subjects were 222(107 male, 115 female) managerial and non-managerial workers in the Rocky Mountain area. Results showed no significant correlations between work-related altitudes and specific religious affiliation or degree of religious conviction. However, religious conviction was significantly finked to organizational rank, with non-managerial employees reporting a higher degree of religious conviction than managerial employees. Protestant workers scored higher in Protestant Work Ethic than did non-Protestants and persons with no religious affiliation had higher need for Power than Protestants, Catholics or affiliates of Eastern religions. 相似文献