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21.
Ecotourism development is closely associated with the sustainability of protected natural areas. When facilitated by appropriate management, ecotourism can contribute to conservation and development, as well as the well-being of local communities. As such, ecotourism has been proposed and practiced in different forms in many places, including China. This study assesses ecotourism development at Xingkai Lake National Nature Reserve in Heilongjiang Province, China. Key informant interviews were conducted with representatives from the provincial Forestry Department, the Nature Reserve, and the local community. Observation was undertaken on three site visits and secondary data were collected. The potential for providing quality natural experiences is high and tourism development is occurring rapidly. However, current relationships between people, resources, and tourism have yet to provide mutual benefits necessary for successful ecotourism. The multi-stakeholder management style and the ambiguity of landownership within the nature reserve constitute structural difficulties for ecotourism management and operation. Although participation in ecotourism could provide a livelihood opportunity and interests in involvement in tourism have been identified among the local fishing community, current involvement is limited mainly due to the lack of mechanisms for participation. Therefore, it is recommended that management programs and government policies should be established to provide a platform for community participation in ecotourism. Then, a positive synergistic relationship between tourism, environment, and community could be developed. Planning and policy requirements are discussed for ecotourism development in protected areas in China. 相似文献
22.
Use of Ordination Techniques to Follow Community Succession from Oil Impact to Recovery in the Field
Edward S. Gilfillan David S. Page Cecile M. Krejsa Sherry A. Hanson Judith C. Foster Geoffrey C. Trussel Bethany S. Whalon 《Chemistry and Ecology》1991,5(1):85-97
Much effort has been directed toward elucidating pollution effects on marine benthic communities (Pearson and Rosenberg, 1978; Sanders et al., 1980; NAS 1985). Less effort has been directed at methods of data analysis which will identify distribution patterns and relationships between communities. Traditional community structure summary parameters such as species richness and various indices of diversity utilize only part of the information contained in a data set and are not very useful in elucidating relationships between communities of animals. 相似文献
23.
24.
Metal binding is an important function of humic acids (HAs) in soils, sediments and waters. At pH 2.0, Mn(II) and Co(NH3)6aq3+ bind tightly in one step labeled A to a solid humic acid NHA isolated from a New Hampshire soil. Two consecutive steps are observed for Hg(II) binding. All the binding isotherms fit the Langmuir model in the temperature range 10.0-50.0 degrees C. Stoichiometric site capacities indicate predominant binding by charge-neutralizing HA carboxylate groups for Mn(II) and the second step A of Hg(II) binding. The binding affinity order in step A is Co(NH3)(6)3+>Hg(II)>Mn(II). Metal binding enthalpy and entropy changes fit the linear correlation found previously for binding of other metal cations by solid HAs. Free energy buffering from cooperative enthalpy and entropy changes and lower enthalpies for metal-HA interactions in solution suggest that desolvation of the cations and HA binding sites as well as HA conformational changes to allow for inner-sphere complexation predominate metal binding by hydrated solid HAs. 相似文献
25.
P. Geoffrey Willis Karen A. Brown Gregory E. Prussia 《Journal of Safety Research》2012,43(5-6):389-396
ProblemResearch on workplace safety has not examined implications for business performance outcomes such as customer satisfaction.MethodIn a U.S. electric utility company, we surveyed 821 employees in 20 work groups, and also had access to archival safety data and the results of a customer satisfaction survey (n = 341).ResultsIn geographically-based work units where there were more employee injuries (based on archival records), customers were less satisfied with the service they received. Safety climate, mediated by safety citizenship behaviors (SCBs), added to the predictive power of the group-level model, but these two constructs exerted their influence independently from actual injuries. In combination, two safety-related predictor paths (injuries and climate/SCB) explained 53% of the variance in customer satisfaction.DiscussionResults offer preliminary evidence that workplace safety influences customer satisfaction, suggesting that there are likely spillover effects between the safety environment and the service environment. Additional research will be needed to assess the specific mechanisms that convert employee injuries into palpable results for customers.Impact on IndustryBetter safety climate and reductions in employee injuries have the potential to offer payoffs in terms of what customers experience. 相似文献
26.
Despite sustained scholarly interest in post‐conflict states, there has not been a thorough review and analysis of associated methodology and the challenges of conducting research in these contexts. Addressing this gap, this paper directs attention to the particular effects of these settings on access and data quality and their ramifications for the resulting scholarship. It assesses the intrinsic challenges of performing fieldwork in these environments, drawing on both relevant social science literature and the authors’ experiences of carrying out research in Afghanistan and Timor‐Leste. The study demonstrates that the post‐conflict environment moulds research design and, consequently, influences how questions are answered as well as the questions asked. Moreover, it highlights ways to mitigate these issues. This work is of relevance to scholars planning to engage in field research and to researchers reflecting upon their work, as well as to policymakers who are considering undertaking programmes or commissioning research in post‐conflict areas. 相似文献
27.
Sexual selection and cuckoldry in a monogamous songbird: implications for sexual selection theory 总被引:11,自引:0,他引:11
Geoffrey E. Hill Robert Montgomerie Christina Roeder Peter Boag 《Behavioral ecology and sociobiology》1994,35(3):193-199
Sexual selection is generally assumed to be weaker in monogamous than in polygynous animals. Recently, though, extra-pair fertilizations have been hailed as an important force in generating variance in reproductive success among males in socially monogamous species, thereby increasing the intensity of sexual selection. To see if extra-pair copulations contribute to variance in male reproductive success in the house finch (Carpodacus mexicanus), we used DNA fingerprinting to determine the paternity of chicks from 35 nests. This species is a socially monogamous passerine in which plumage brightness serves as a sexually selected indicator of male quality. Out of 119, nestlings 10 (8.3%) were fathered by a male other than the attending male, but cuckoldry occurred randomly with respect to the plumage colouration, size, or age of the attending male. Thus extra-pair fertilizations do not generate variance in male reproductive success with respect to plumage colour. On the other hand, a strongly male-biased sex ratio and asynchronous breeding by females may generate substantial variance in male reproductive success and could explain the evolution of ornamental colouration. 相似文献
28.
Electrocoagulation is an electrochemical method of treating polluted water whereby sacrificial anodes corrode to release active coagulant precursors (usually aluminium or iron cations) into solution. Accompanying electrolytic reactions evolve gas (usually as hydrogen bubbles) at the cathode. Electrocoagulation has a long history as a water treatment technology having been employed to remove a wide range of pollutants. However electrocoagulation has never become accepted as a 'mainstream' water treatment technology. The lack of a systematic approach to electrocoagulation reactor design/operation and the issue of electrode reliability (particularly passivation of the electrodes over time) have limited its implementation. However recent technical improvements combined with a growing need for small-scale decentralised water treatment facilities have led to a re-evaluation of electrocoagulation. Starting with a review of electrocoagulation reactor design/operation, this article examines and identifies a conceptual framework for electrocoagulation that focuses on the interactions between electrochemistry, coagulation and flotation. In addition detailed experimental data are provided from a batch reactor system removing suspended solids together with a mathematical analysis based on the 'white water' model for the dissolved air flotation process. Current density is identified as the key operational parameter influencing which pollutant removal mechanism dominates. The conclusion is drawn that electrocoagulation has a future as a decentralised water treatment technology. A conceptual framework is presented for future research directed towards a more mechanistic understanding of the process. 相似文献
29.
Natural attenuation of mecoprop has been studied by determining changes in enantiomeric fraction in different redox environments down gradient from a landfill in the Lincolnshire limestone. Such changes could be due to differential metabolism of the enantiomers, or enantiomeric inversion. In order to confirm the processes occurring in the field, microcosm experiments were undertaken using limestone acclimatised in different redox zones. No biodegradation was observed in the methanogenic, sulphate-reducing or iron-reducing microcosms. In the nitrate-reducing microcosm (S)-mecoprop did not degrade but (R)-mecoprop degraded with zero order kinetics at 0.65 mg l(-1)day(-1) to produce a stoichiometric equivalent amount of 4-chloro-2-methylphenol. This metabolite only degraded when the (R)-mecoprop disappeared. In aerobic conditions (S)- and (R)-mecoprop degraded with zero order kinetics at rates of 1.90 and 1.32 mg l(-1)day(-1) respectively. The addition of nitrate to dormant iron-reducing microcosms devoid of nitrate stimulated anaerobic degradation of (R)-mecoprop after a lag period of about 20 days and was associated with the production of 4-chloro-2-methylphenol. Nitrate addition to sulphate-reducing/methanogenic microcosms did not stimulate mecoprop degradation. However, the added nitrate was completely utilised in oxidising sulphide to sulphate. There was no evidence for enantiomeric inversion. The study reveals new evidence for fast enantioselective degradation of (R)-mecoprop under nitrate-reducing conditions. 相似文献
30.
Geologic occurrences of erionite in the United States: an emerging national public health concern for respiratory disease 总被引:1,自引:0,他引:1
Bradley S. Van Gosen Thomas A. Blitz Geoffrey S. Plumlee Gregory P. Meeker M. Patrick Pierson 《Environmental geochemistry and health》2013,35(4):419-430
Erionite, a mineral series within the zeolite group, is classified as a Group 1 known respiratory carcinogen. This designation resulted from extremely high incidences of mesothelioma discovered in three small villages from the Cappadocia region of Turkey, where the disease was linked to environmental exposures to fibrous forms of erionite. Natural deposits of erionite, including fibrous forms, have been identified in the past in the western United States. Until recently, these occurrences have generally been overlooked as a potential hazard. In the last several years, concerns have emerged regarding the potential for environmental and occupational exposures to erionite in the United States, such as erionite-bearing gravels in western North Dakota mined and used to surface unpaved roads. As a result, there has been much interest in identifying locations and geologic environments across the United States where erionite occurs naturally. A 1996 U.S. Geological Survey report describing erionite occurrences in the United States has been widely cited as a compilation of all US erionite deposits; however, this compilation only focused on one of several geologic environments in which erionite can form. Also, new occurrences of erionite have been identified in recent years. Using a detailed literature survey, this paper updates and expands the erionite occurrences database, provided in a supplemental file (US_erionite.xls). Epidemiology, public health, and natural hazard studies can incorporate this information on known erionite occurrences and their characteristics. By recognizing that only specific geologic settings and formations are hosts to erionite, this knowledge can be used in developing management plans designed to protect the public. 相似文献