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831.
This paper examines the recent evolution in the governance of protected area tourism in China. China now sees cooperation
in the form of public-private partnerships occurring between authorized private tourism enterprises in various organizational
forms and the public managers from specific portfolio departments of governments at different levels. Three types of governance
models are visible: the Leasing Model, the Non-listed Share-holding Model, and the Public-listed Share-holding Model. Theories
of corporate governance were applied to these models to analyze the internal and external mechanisms of supervision and incentives
for both the government agencies and the authorized tourism enterprises for nature-based tourism operations. The Principal-Agent
problem and the supervision mechanism are the focus of the analysis. The emerging governance approaches for tourism in protected
areas of China are all theoretically viable, as explained by the theory of property rights and corporate governance, and practically
viable as elaborated in the cases of the three types of governance models summarized in this paper. 相似文献
832.
介绍了真空碳酸钠-克劳斯工艺在焦化厂焦炉煤气脱硫及硫回收中的应用,主要介绍了工艺流程、主要设备和监测结果,并对此工艺进行了简要评价。 相似文献
833.
Shouliang Huo Chunzi M Beidou Xi Jing Su Fengyu Zan Danfeng Ji Zhuoshi He 《环境科学学报(英文版)》2013,25(10):2014-2022
The trophic status assessment of lakes in different lake regions may provide important and fundamental information for lake trophic state classification and eutrophication control. In this study, a region-specific lake eutrophication assessment standard was established through a frequency distribution method based on chlorophyll-a concentration. The assessment standards under the oligotrophic state for lakes in the Eastern plain, Yungui Plateau, Northeast Plain and Mountain Mongolia-Xinjiang regions are total phosphorus of 0.068, 0.005, 0.011, 0.005 mg/L; total nitrogen of 1.00, 0.16, 0.37, 0.60 mg/L; Secchi depth of 0.60, 8.00, 1.55, 3.00 m; and CODMn of 2.24, 1.00, 5.1 l, 4.00 mg/L, respectively. Moreover, a region-specific comprehensive trophic level index was developed to provide an understandable assessment method for the public. The results indicated that the frequency distribution analysis based on chlorophyll-a combined with trophic level index provided a useful metric for the assessment of the lake trophic status. In addition, the difference of eutrophication assessment standards in different lake regions was analyzed, which suggested that the sensitivities of algae to nutrients and the assessment standard of trophic status possessed significant regional differences for the four lake ecoregions. Lake eutrophication assessment standards would contribute to maximizing the effectiveness of future management strategies, to control and minimize lake eutrophication problems. 相似文献
834.
Ni Lixiao Li Danye Rong Shiyi Su Lili Zhou Wei Wang Peifang Wang Chao Li Shiyin Acharya Kumud 《Environmental science and pollution research international》2017,24(26):21091-21102
Environmental Science and Pollution Research - This paper focuses on the characterization of extracellular polymeric substances (EPS), which are composed of soluble EPS (SL-EPS), loosely bound EPS... 相似文献
835.
836.
Györgyi Bela Taru Peltola Juliette C. Young Bálint Balázs Isabelle Arpin György Pataki Jennifer Hauck Eszter Kelemen Leena Kopperoinen Ann Van Herzele Hans Keune Susanne Hecker Monika Suškevičs Helen E. Roy Pekka Itkonen Mart Külvik Miklós László Corina Basnou Joan Pino Aletta Bonn 《Conservation biology》2016,30(5):990-999
The number of collaborative initiatives between scientists and volunteers (i.e., citizen science) is increasing across many research fields. The promise of societal transformation together with scientific breakthroughs contributes to the current popularity of citizen science (CS) in the policy domain. We examined the transformative capacity of citizen science in particular learning through environmental CS as conservation tool. We reviewed the CS and social‐learning literature and examined 14 conservation projects across Europe that involved collaborative CS. We also developed a template that can be used to explore learning arrangements (i.e., learning events and materials) in CS projects and to explain how the desired outcomes can be achieved through CS learning. We found that recent studies aiming to define CS for analytical purposes often fail to improve the conceptual clarity of CS; CS programs may have transformative potential, especially for the development of individual skills, but such transformation is not necessarily occurring at the organizational and institutional levels; empirical evidence on simple learning outcomes, but the assertion of transformative effects of CS learning is often based on assumptions rather than empirical observation; and it is unanimous that learning in CS is considered important, but in practice it often goes unreported or unevaluated. In conclusion, we point to the need for reliable and transparent measurement of transformative effects for democratization of knowledge production. 相似文献
837.
838.
839.
Su Y Hung H Stern G Sverko E Lao R Barresi E Rosenberg B Fellin P Li H Xiao H 《Journal of environmental monitoring : JEM》2011,13(11):3111-3118
Initiated in 1992, air monitoring of organic pollutants in the Canadian Arctic provided spatial and temporal trends in support of Canada's participation in the Stockholm Convention of Persistent Organic Pollutants. The specific analytical laboratory charged with this task was changed in 2002 while field sampling protocols remained unchanged. Three rounds of intensive comparison studies were conducted in 2004, 2005, and 2008 to assess data comparability between the two laboratories. Analysis was compared for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in standards, blind samples of mixed standards and extracts of real air samples. Good measurement accuracy was achieved for both laboratories when standards were analyzed. Variation of measurement accuracy over time was found for some OCPs and PCBs in standards on a random and non-systematic manner. Relatively low accuracy in analyzing blind samples was likely related to the process of sample purification. Inter-laboratory measurement differences for standards (<30%) and samples (<70%) were generally less than or comparable to those reported in a previous inter-laboratory study with 21 participating laboratories. Regression analysis showed inconsistent data comparability between the two laboratories during the initial stages of the study. These inter-laboratory differences can complicate abilities to discern long-term trends of pollutants in a given sampling site. It is advisable to maintain long-term measurements with minimal changes in sample analysis. 相似文献
840.
Xia D He C Zhu L Huang Y Dong H Su M Asi MA Bian D 《Journal of environmental monitoring : JEM》2011,13(4):864-870
The objective of this work was to develop a novel wet-scrubbing process using Fe(VI) for the simultaneous removal of gaseous NO and SO(2). The oxidation of SO(2) and NO with Fe(VI) was studied in aqueous solution at alkaline pH (9.0-11.0). A stoichiometric molar ratio for NO and SO(2) oxidation with Fe(VI) was determined to be nearly 3.0. Sulfate and nitrate was identified as final products by ion chromatography from the reaction at pH 9.0-11.0. The feasibility of simultaneous removal of multiple gas pollutants with the continuous feeding of ferrate in lab-scale was investigated from the view of industrial application. It was found that the removal efficiency of NO and SO(2) was enhanced with the increase of Fe(VI) concentration, more than 90% NO removal efficiency and 100% SO(2) removal efficiency were achieved by wet-scrubbing process using Fe(VI) at room temperature and ambient atmosphere. The results demonstrate that Fe(VI) could be an effective wet-scrubbing agent for the simultaneous removal of NO and SO(2). 相似文献