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281.
Meier Sebastián Moore Francisca González María-Eugenia Medina Jorge Campos Pedro Khan Naser Cumming Jonathan Sanhueza Mario Mejías Jaime Morales Arturo Hirzel Juan Seguel Alex 《Environmental geochemistry and health》2021,43(4):1441-1456
Environmental Geochemistry and Health - Biochar (BC) is a porous, carbonaceous material produced by slow pyrolysis of biomass under oxygen-limited conditions. BC production has been attracting... 相似文献
282.
There is a paucity of research on the subjective stress‐related experiences of humanitarian aid workers. Most evaluations of stress among these individuals focus on trauma and related conditions or adopt a quantitative approach. This interview‐based study explored how 58 humanitarian aid workers employed by a United Nations‐aligned organisation perceived the transactional stress process. The thematic analysis revealed eight main topics of interest: an emergency culture was found where most employees felt compelled to offer an immediate response to humanitarian needs; employees identified strongly with humanitarian goals and reported a high level of engagement; the rewards of humanitarian work were perceived as motivating and meaningful; constant change and urgent demands resulted in work overload; and managing work–life boundaries and receiving positive support from colleagues and managers helped to buffer perceived stress, work overload, and negative health outcomes. The practical implications of the results are discussed and suggestions made in the light of current research and stress theory. 相似文献
283.
Gagnon PR Passmore HA Platt WJ Myers JA Paine CE Harms KE 《Ecology》2010,91(12):3481-6; discussion 3503-14
Pyrogenic plants dominate many fire-prone ecosystems. Their prevalence suggests some advantage to their enhanced flammability, but researchers have had difficulty tying pyrogenicity to individual-level advantages. Based on our review, we propose that enhanced flammability in fire-prone ecosystems should protect the belowground organs and nearby propagules of certain individual plants during fires. We base this hypothesis on five points: (1) organs and propagules by which many fire-adapted plants survive fires are vulnerable to elevated soil temperatures during fires; (2) the degree to which burning plant fuels heat the soil depends mainly on residence times of fires and on fuel location relative to the soil; (3) fires and fire effects are locally heterogeneous, meaning that individual plants can affect local soil heating via their fuels; (4) how a plant burns can thus affect its fitness; and (5) in many cases, natural selection in fire-prone habitats should therefore favor plants that burn rapidly and retain fuels off the ground. We predict an advantage of enhanced flammability for plants whose fuels influence local fire characteristics and whose regenerative tissues or propagules are affected by local variation in fires. Our "pyrogenicity as protection" hypothesis has the potential to apply to a range of life histories. We discuss implications for ecological and evolutionary theory and suggest considerations for testing the hypothesis. 相似文献
284.
Even though “sustainable development” seems to have emerged as the development paradigm of the 1990s, a great deal of vagueness
still surrounds the meaning, definition, and theoretical underpinnings of the concept. There is also a general lack of emphasis
on the spatial dimension of sustainable development when developing relevant conceptual or environmental accounting frameworks.
In clarifying the concept, this article proposes a definition that explicitly incorporates the temporal as well as the spatial
dimension of sustainability. It also develops a logically consistent conceptual framework for the analysis and evaluation
of sustainable development, following a spatial systems approach. Five interconnected aspatial subsystems or subsets of a
spatial system are identified and their respective operational dimensions discussed. A proposed composite index calleddegree of stainable development (DSD) and its five component indicators are also outlined. The difficulties involved in operationalizing the DSD measure
and the conceptual framework are noted, and the various tasks that need to be undertaken in this regard are specified. It
is concluded that future research utilizing the proposed conceptual framework should not only foster the development of appropriate
methodologies for the comparative evaluation of sustainable development at global, national, or regional scales, but also
offer insights to appropriate decision makers at various levels regarding available options and alternative actions for the
healthy development of their respective societies. 相似文献
285.
Jonathan D. Choquette Jacqueline D. Litzgus Joanne X. Y. Gui Trevor E. Pitcher 《Conservation biology》2023,37(1):e14016
Advancements in the field of reintroduction biology are needed, but understanding of how to effectively conduct translocations, particularly with snakes, is lacking. We conducted a systematic review of snake translocation studies to identify potential tactics for reducing postrelease effects. We included studies on intentional, human-mediated, wild–wild, or captive–wild translocations to any location, regardless of motive or number of snakes translocated. Only studies that presented results for at least 1 of 4 outcomes (movement behavior, site fidelity, survival, or population establishment) were included. We systematically searched 4 databases for published studies and used 5 methods to search the gray literature. Our search and screening criteria yielded 121 data sources, representing 130 translocation cases. We quantified the association between 15 translocation tactics and short-term translocation outcomes by calculating odds ratios and used forest plots to display results. Snake translocations involved 47 species (from mainly 2 families), and most were motivated by research, were monitored for at least 6 months, occurred in North America, and took place from the 1990s onward. The odds of a positive snake translocation outcome were highest with release of captive reared or juvenile snakes, release of social groups together, delayed release, provision of environmental enrichment or social housing before release, or minimization of distance translocated. The odds of a positive outcome were lowest when snakes were released early in their active season. Our results do not demonstrate causation, but outcomes of snake translocation were associated with 8 tactics (4 of which were strongly correlated). In addition to targeted comparative studies, we recommend practitioners consider the possible influence of these tactics when planning snake translocations. 相似文献
286.
This paper describes the construction and empirical evaluation of a new scale for measuring empowering leader behavior. Study One consisted of thorough interviews with external leaders and team members in three organizations. Behaviors elicited in the interviews were classified by researchers into eight categories of leader empowering behavior and the Empowering Leadership Questionnaire (ELQ) was constructed to measure each of these categories. In Study Two, the ELQ was administered to team members and leaders from two organizations. The results indicated that five‐factors (Coaching, Informing, Leading By Example, Showing Concern/Interacting with the Team, and Participative Decision‐Making) adequately describe the data. In Study Three, we cross‐validated the scale in a sample from five organizations and the factor analysis confirmed the five‐factor model. The ELQ dimensions were also compared with behaviors measured by two well‐established measures of leader behavior. The results indicated that the ELQ dimensions partially overlap with previously identified constructs, but that empowering leadership behavior can not be entirely accounted for by the earlier measures. Definitions and implications for the categories of empowering leader behaviors are offered. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
287.
288.
HydroShare: Sharing Diverse Environmental Data Types and Models as Social Objects with Application to the Hydrology Domain 下载免费PDF全文
289.
Hispanic residents suffer disproportionately from exposure to toxic pollution hazards, but little is known about why some Hispanic residents live in high-risk neighbourhoods while others are protected from similar risks. This study uses comparative interview-based methods to further understanding of Hispanic people’s residential decision-making and their associated exposures to hazardous air pollutants (HAPs) in the Miami Metropolitan Statistical Area (Florida), which is home to one of the most diverse Hispanic populations in the U.S. We use 22 in-depth interviews conducted with Hispanic householders living at high and low risk to HAPs, selected from a larger representative phone survey of 650 local residents. For Hispanic households at high risk, economic constraints, family ties, desiring a central location, a sense of community, and comfort in a shared culture contributed to their residences in high risk locations. In contrast, protective factors for Hispanic households living at low risk included the desire to live in an ethnically diverse setting, the ease of finding service work, and preferring environmental amenities and exclusivity. Findings demonstrate that there are considerable differences in factors shaping residential decision-making of low- and high-risk Hispanic residents, but that all were influenced by economic, socio-cultural, and environmental considerations to varying degrees. 相似文献
290.
Jonathan W. Peterson Theresa A. O'Meara Wei Wang 《Environmental pollution (Barking, Essex : 1987)》2009,157(6):1849-1856
Raman spectroscopy was used to investigate sorption mechanisms of cephapirin (CHP), a veterinary antibiotic, onto quartz (SiO2) and feldspar (KAlSi3O8) at different pH. Sorption occurs by electrostatic attraction, monodentate and bidentate complexation. The zwitterion (CHPo) adsorbs to a quartz(+) surface by electrostatic attraction of the carboxylate anion group (-COO−) at low pH, but adsorbs to a quartz(−) surface through electrostatic attraction of the pyridinium cation, and possibly COO− bridge complexes, at higher pH. CHP− bonds to quartz(−) surfaces by bidentate complexation between one oxygen of -COO− and oxygen from carbonyl of an acetoxymethyl group. On a feldspar(+/−) surface, CHPo forms monodentate complexes between CO, and possible -COO− bridges and/or electrostatic attachments to localized edge (hydr)oxy-Al surfaces. CHP− adsorbs to feldspar(−) through monodentate CO complexation. Similar mechanisms may operate for other cephalosporins. Results demonstrate, for the first time, that Raman techniques can be effective for evaluating sorption mechanisms of antibiotics. 相似文献