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91.
2010年广州亚运期间空气质量与污染气象条件分析 总被引:9,自引:2,他引:7
利用2010年11月4日~12月10日广州地区NO2、O3、SO2、PM、能见度实测资料,区域空气污染指数RAQI及大气输送扩散特征参数,分析广州亚运期间空气质量与气象条件变化特征.结果表明,亚运期间空气质量比亚运前后好,能见度比亚运前后大,PM1和PM2.5浓度比亚运前后小,能见度与PM1和PM2.5有较好的反相关;亚运期间NO2和SO2日均值和小时均值均达到国家一级标准,PM10日均值和O3小时均值均满足国家二级标准,污染物得到较好的控制;广州地区SO2受本地源和外地源远距离输送叠加影响,NO2受本地源影响较大;广州周边城市NO2、SO2和PM10有向广州输送的潜势,而广州O3有向其周边城市扩散的潜势;亚运期间污染气象条件比亚运前后有利,亚运期间污染物浓度降低得益于政府实施的减排措施及良好的气象条件. 相似文献
92.
中国典型冰雪旅游地开发模式及优化路径 总被引:3,自引:0,他引:3
北京冬奥会的筹办为中国冰雪旅游发展带来巨大契机,促进了冰雪旅游地的蓬勃发展。基于冰雪旅游地系统理论,构建了冰雪旅游地发展水平评价指标体系,并利用层次分析法、熵权法及加权Topsis法,对崇礼、亚布力、神农架、西岭雪山四个中国典型冰雪旅游地发展水平进行了测度。结果表明:崇礼冰雪旅游发展水平最高,亚布力次之,神农架及西岭雪山仍有待提升。基于此,提炼出四种典型冰雪旅游地开发模式,包括资源主导内驱模式、市场主导外驱模式、资源市场双核共驱模式以及资源市场政策综合齐驱模式。同时,从冰雪旅游地系统视角,提出了中国冰雪旅游地开发优化路径。研究有助于丰富冰雪旅游开发相关理论,为中国冰雪旅游地高质量发展提供智力支撑和案例借鉴。 相似文献
93.
Modern ecologico-cybernetic principle is of importance to decreasing damages in relation to agricultural productions. As an illustration of this, the authors studied some of the questions about the optimal policy of choosing actions for the antifrost measures of winter wheat by means of the finite-stage model of Markov Decision Programming (MDP). The related data came from the investigation results of the investigated region in the northeastern part of Henan, China. First, the authors give the states, ecologico-cybernetic action measures, transition probabilities and reward values in relation to these antifrost action measures of winter wheat crop. Second, the authors describe the principles and computational procedures of the ecologico-cybernetic decision-makings based on the finite-stage model of MDP. Third, a simple table applicable to the decision-making practice is given. Finally, we evaluate the results of this study, point out their shortcomings and suggest that this method is applicable to the other fields in relation to decreasing damage ecologico-cybernetics. 相似文献
94.
Garry D. Brewer 《Sustainability Science》2007,2(2):159-177
The complexity of mixed social, behavioral, and natural systems—such as those encountered while analyzing, understanding, and trying to manage aspects of climate change and sustainability, requires more common theoretical frameworks and technical tools than either can bear. How does human activity relate to greenhouse gas emissions, changes in the atmosphere, climate variability, and multiple impacts, outcomes, and effects? Some of the connections can be observed and measured, many cannot. Uncertainties of every conceivable sort can occur. As the time frame into the future extends, uncertainties essentially dominate conventional theories, tools, experiences, habits, processes, and so forth. The scientific consensus linking human activity to climate change is now all but settled according to The Fourth Assessment Report of the Intergovernmental Panel on Climate Change. The consensus says little, however, about who should be doing what and for what reasons under this singular, even unique circumstance. There are no data about the future on which to rely. We are challenged to imagine many different and possible “futures” as humankind seeks to exert its mastery and control. This essay considers and then weaves together several basic issues, ideas, and topics: complexity, the concept of human intentionality, several means used to exert control in organizations and social systems, and different methods being used to imagine, invent, and communicate the future. 相似文献
95.
围绕南京城市环境主要问题对国际访客和南京市民进行调查,分别发放186和205份问卷,其中有效问卷为178和200份,回收率分别为95.7%和97.6%,使用拟合优度方法检验。结果表明,国际访客对南京城市环境的满意度明显低于南京市民;国际访客对旅游区环境更看重;两者都认为视觉环境中的户外广告、城市绿化和城市扬尘是南京主要城市环境问题,而政府和普通市民是最应该对南京城市环境问题负责的群体,但南京市民更倾向把环保问题推给政府。围绕调查问卷中所反映的3大主要环境问题,本研究还对北京、新加坡、美国加利福尼亚州等国内外先进地区进行案例分析和经验总结,可为解决南京城市环境问题提供新的思路。 相似文献
96.
SUZANNE C. GRIFFIN‡§ TANGUY VALOIS† MARK L. TAPER‡ L. SCOTT MILLS 《Conservation biology》2007,21(4):1070-1081
Abstract: If changes in animal behavior resulting from direct human disturbance negatively affect the persistence of a given species or population, then these behavioral changes must necessarily lead to reduced demographic performance. We tested for the effects of human disturbance on Olympic marmots ( Marmota olympus ), a large ground-dwelling squirrel that has disappeared from several areas where recreation levels are high. We assessed the degree to which antipredator and foraging behavior and demographic rates (survival and reproduction) differed between sites with high recreation levels (high use) and those with little or no recreation (low use). Compared with the marmots at low-use sites, marmots at high-use sites displayed significantly reduced responses to human approach, which could be construed as successful accommodation of disturbance or as a decrease in predator awareness. The marmots at high-use sites also looked up more often while foraging, which suggests an increased wariness. Marmots at both types of sites had comparable reproductive and survival rates and were in similar body condition. Until now, the supposition that marmots can adjust their behavior to avoid negative demographic consequences when confronted with heavy tourism has been based on potentially ambiguous behavioral data. Our results support this hypothesis in the case of Olympic marmots and demonstrate the importance of considering demographic data when evaluating the impacts of recreation on animal populations. 相似文献
97.
98.
Lu Liu Xinfeng Wang Jianmin Chen Likun Xue Wenxing Wang Liang Wen Dandan Li Tianshu Chen 《环境科学学报(英文版)》2018,30(9):249-260
Peroxyacetyl nitrate(PAN), as a major secondary pollutant, has gained increasing worldwide attentions, but relevant studies in China are still quite limited. During winter of 2015 to summer of 2016, the ambient levels of PAN were measured continuously by an automatic gas chromatograph equipped with an electron capture detector(GC–ECD) analyzer at an urban site in Jinan(China), with related parameters including concentrations of O3, NO, NO_2, PM_(2.5), HONO,the photolysis rate constant of NO_2 and meteorological factors observed concurrently. The mean and maximum values of PAN concentration were(1.89 ± 1.42) and 9.61 ppbv respectively in winter, and(2.54 ± 1.44) and 13.47 ppbv respectively in summer. Unusually high levels of PAN were observed during severe haze episodes in winter, and the formation mechanisms of them were emphatically discussed. Study showed that high levels of PAN in winter were mainly caused by local accumulation and strong photochemical reactions during haze episodes, while mass transport played only a minor role. Accelerated photochemical reactions(compared to winter days without haze) during haze episodes were deduced by the higher concentrations but shorter lifetimes of PAN, which was further supported by the sufficient solar radiation in the photolysis band along with the high concentrations of precursors(NO_2, VOCs) and HONO during haze episodes. In addition, significant PAN accumulation during calm weather of haze episodes was verified by meteorological data. 相似文献
99.
100.