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41.
The research adopts open sampling method and TCT-GC/MS (Thermodesorption Cold Trap-Gas Chromatography/Mass Spectrometery) apparatus to collect and analyze the volatile organic compounds(VOCs) of Platycladus orientalis forest, with the intention of researching the compounds and diurnal variation of VOCs of P. orientalis forest in natural state in Beijing Western Hills in spring. The results are as follows: (1) There are 160 kinds (11 categories) of volatile organic compounds, containing Alkyl Hydrocarbon, Ketone, Alcohol, Acid, Aldehyde, Alkene, Ester, Aromatic hydrocarbon, Ether, Hydroxybenzene and Amide. The content of Alkyl Hydrocarbon, Ketone, Acid and Aldehyde occupy a greater percentage among all compounds. (2) The diurnal variation curve of total volatile organic compounds (TVOC) is characterized as "one peak at 11:00(36.44%) and one vale at 3:00(12.76%)". Generally, the concentration at daytime is higher than that of night, and higher in morning than in afternoon, with the maximum at noon. (3) The change of Alkyl Hydrocarbon concentration is greater in the morning and about midday, less in the afternoon and night. The diurnal variation curve of Ketone concentration appears as "three peaks and three vales". 1:00, 5:00—7:00 and 11:00 are peak time, 3:00, 9:00 and 17:00 are vale time. As to Acid, its concentration appears two obvious phases: the higher phase is from 9:00 to 17:00, with the maximum at 11:00, and the lower phase is from 19:00 to 7:00, with the minimum at 5:00. Concerning Aldehyde concentration, 17:00 and 19:00 are the higher phases and also has obvious difference with other time, while the lower phrase has no obvious difference with each other. (4) Alkene is the most important compound to human health. Its concentration appears as "one peak" at 15:00, which has obvious difference with other time. Totally, its content at daytime is higher than that at night, and higher in afternoon than in morning. 相似文献
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郊野公园游憩度评价体系构建研究 总被引:1,自引:1,他引:0
城市化的快速发展使得人们日渐远离自然,人们对郊野公园的游憩需求正不断增加。文章通过查阅文献并咨询专家,对郊野公园的游憩要素进行分类,从生态空间、游憩空间、人文价值、地形、水体、植被、设施7个角度出发,选取了18个指标,运用层次分析法对18个指标的权重进行判定,构建郊野公园游憩度评价体系。从构建的体系结果来看,生态空间空气清洁度高、生态空间面积适宜、游憩空间活动类型丰富的郊野公园具有较高的游憩度。且郊野公园的游憩特点为空间感舒适、野趣、清洁、安全。对郊野公园游憩度的研究,可以引导游人理性使用郊野公园的游憩资源,对提高郊野公园的游憩质量提供理论指导。 相似文献
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干旱缺水和生境不良使世界上许多地区的植被恢复和生态改善面临困难。为了提高植被成活率、遏制土壤侵蚀和土地退化态势,国内外许多重点地区都开展了多种微地形改造与下垫面整地措施,使得地表生境和植被状况得到一定改善。但微地形改造对生态环境影响的基础研究仍严重滞后于实践的客观需求,许多关键效应和科学机理不明。本文系统梳理和总结了国内外学者在不同生态系统类型区和自然地理单元上开展的相关研究。认为微地形改造对土壤属性和微生境、降雨入渗和水蚀过程、植被恢复的效果及其生态服务功能发挥等多个方面都有重要影响,并综述了相关研究进展。同时指出当前微地形改造研究中存在的突出问题。包括科学分类标准有待系统化、实地量化技术相对滞后、微地形改造的水文效应有待强化、影响植被恢复的机理不明等若干重要局限。建议应进一步加强微地形改造的分类体系研发、发展微地形改造方式的定量刻画技术;设立野外定位站,跟踪监测其长期效应,并加强不同微地形改造措施的生态环境效应对比,为科学筛选和优化下垫面改造技术、服务区域生态改善和应对气候变化提供科学依据。 相似文献
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为游憩者创造良好的行为环境 总被引:2,自引:3,他引:2
汤晓敏 《上海交通大学学报(农业科学版)》2001,19(3):206-210
本文在分析游憩行为环境的涵义和作用的基础上.以行为心理学的理论为指导.从满足游憩者的游憩体验的角度出发.系统的阐述了与游憩行为环境的设计密切相关的种种因素,以期对现代游憩环境的设计与建设起到一定的参考与借鉴作用. 相似文献
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Susan A. Schroeder Louis Cornicelli David C. Fulton Steven S. Merchant 《Human Dimensions of Wildlife》2018,23(1):1-20
Although research has advanced methods for clarifying factors that relate to customer satisfaction, they have not been embraced by leisure researchers. Using results from a survey of wild turkey hunters, we applied traditional and revised importance-performance (IPA/RIPA), importance-grid analysis (IGA), and penalty-reward-contrast analysis (PRCA) to examine how activity-specific factors influenced satisfaction. Results suggested differences between the explicit and implicit importance of factors related to turkey hunting. Opportunities to kill turkeys were explicitly rated as less important than seeing, hearing, or calling in turkeys, but opportunities for harvest had relatively higher levels of implicit importance. PRCA identified “calling turkeys in” and “hearing gobbling” as minimum requirements that cause dissatisfaction if not fulfilled, but do not provide satisfaction, whereas “seeing turkeys” and an “opportunity to kill a turkey” related to both satisfaction and dissatisfaction. RIPA, IGA, and PRCA could provide valuable insights about factors that may improve satisfaction for leisure participants. 相似文献
49.
研究了旅游需求曲线和消费者剩余曲线的内在关联与异同,给出了游憩资源消费者剩余的计算方法.在此基础上,对目前消费者剩余计算积分上、下限确定中常见的4种错误进行分析,结果表明游憩价值不仅仅是消费者剩余. 相似文献
50.
Urban forest parks, such as Fuzhou National Forest Park (FNFP), provide residents with landscape amenities, recreational opportunities, and interaction with nature. Understanding the recreational quality of green spaces and visitors’ behaviors and preferences is essential for effective forest park conservation strategy. We aimed to assess the recreational use and amenities of FNFP and calculate the monetary value of provided services using a contingent valuation method (CVM). A total of 249 park visitors were interviewed face-to-face based on a questionnaire using entrance fee as the payment vehicle, in October 2015 and January 2016. A considerable number of protest responses may cause selectivity bias; consequently, we used models excluding protest zeros. Sample selection models were estimated using Heckman’s two-step and full information maximum likelihood methods The average willingness-to-pay (WTP) was estimated to be 13.79 RMB (equivalent to 2.00 USD) for the unconditional model, and the lower mean values were estimated for two selectivity bias corrected models. In this case, park visitors would be willing to pay an average 11.6 RMB (equivalent to 1.69 USD) per person according to the full information maximum likelihood estimate and an average 10.96 RMB (equivalent to 1.60 USD) per person by the two-step method. Respondents’ satisfaction of forest park facilities and service significantly influenced their WTP value for forest park improvements. Socio-demographic features could not effectively discriminate the protest bidders and the other non-protest bidders. Our results suggest that protesters may value the resource less than positive bidders. The high percentage of protest respondents may be due to the current free use of FNFP and payment vehicle of entrance fee. The CVM approach takes residents’ preferences into consideration and allows the study of heterogenous socio-demographic groups; thus, our data may help to develop effective management plans for improving urban forest parks in China. 相似文献