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191.
Management of natural environment sites is becoming increasingly complex because of the influx of urbanized society into wildland areas. This worldwide phenomenon impacts a wide range of countries. In southern California ethnicity is often a major factor influencing recreation site use and behavior at sites in the wildland-urban interface. This study investigated the role of ethnicity and race on the use patterns, perception of environment, and recreation behaviors at an outdoor recreation site visited by an ethnically diverse population. Two research questions were asked: (1) What ethnic groups engage in outdoor recreation at this site, and (2) what differences can be assigned to these various groups? Data were collected from 250 recreationists during 1991. Three major ethnic groups were identified, and statistically significant differences were found in the importance of site attributes, activity participation, and in preferred and actual communication channels. Management implications and strategies based on group differences are discussed. 相似文献
192.
旅游用地是一种特殊的土地资源类型,一直没有得到应有的重视。在实际利用中存在着许多突出问题,如旅游景点的土地利用规划与旅游规划不协调,旅游用地中的景观设计的人为性,旅游用地资源环境污染和破坏,旅游用地中的产权关系混乱,以及打生态旅游牌搞房地产开发等。研究提出了加强旅游用地立法,做好土地规划与旅游规划,对旅游用地进行估价,实行用地来源的多途径化与统一管理等对策。它是一项探索式研究,具有开创性,旨在为旅游资源的可持续发展做初步探讨。 相似文献
193.
194.
Hu Li Jianjun Qiu Ligang Wang Huajun Tang Changsheng Li Eric Van Ranst 《Agriculture, ecosystems & environment》2010,135(1-2):24-33
Agricultural production plays an important role in affecting atmospheric greenhouse gas concentrations. Field measurements were conducted in Quzhou County, Hebei Province in the North China Plains to quantify carbon dioxide (CO2) and nitrous oxide (N2O) emissions from a winter wheat–maize rotation field, a common cropping system across the Chinese agricultural regions. The observed flux data in conjunction with the local climate, soil and management information were utilized to test a process-based model, Denitrification–Decomposition or DNDC, for its applicability for the cropping system. The validated DNDC was then used for predicting impacts of three management alternatives (i.e., no-till, increased crop residue incorporation and reduced fertilizer application rate) on CO2 and N2O emissions from the target field. Results from the simulations indicated that (1) CO2 emissions were significantly affected by temperature, initial SOC, tillage method, and quantity and quality of the organic matter added in the soils; (2) increases in temperature, initial SOC, total fertilizer N input, and manure amendment substantially increased N2O emissions; and (3) temperature, initial SOC, tillage, and quantity and quality of the organic matter added in the soil all had significant effects on global warming. Finally, five 50-year scenarios were simulated with DNDC to predict their long-term impacts on crop yield, soil C dynamics, nitrate leaching losses, and N2O emissions. The modelled results suggested that implementation of manure amendment or crop residue incorporation instead of increased fertilizer application rates would more efficiently mitigate GHG emissions from the tested agro-ecosystem. The multi-impacts provided a sound basis for comprehensive assessments on the management alternatives. 相似文献
195.
环境优美乡镇建设探析——以米易县湾丘彝族乡创建省级环境优美乡镇为例 总被引:2,自引:0,他引:2
环境优美乡镇建设的根本目的是实现区域的可持续发展,一方面大力发展经济,合理开发利用资源;另一方面要防治社会经济活动的环境污染,保护生态环境,实现经济社会和生态环境的协调发展。文章以湾丘彝族乡创建省级优美乡镇为例,找出创建环境优美乡镇存在的薄弱环节,并结合湾丘彝族乡创建环境优美乡镇的有利条件与不利条件,从经济、技术、管理、宣传四个方面探析环境优美乡镇建设的对策,从而为环境优美乡镇的创建创造条件,为群众创造一个优美、舒适的人居环境。 相似文献
196.
The purpose of this study was to investigate the anatomical and physiological differences between two Leymus chinensis ecotypes coexisted in semi-humid meadow and semi-arid steppe. The study addressed the hypothesis that, at same habitat, the two ecotypes exhibit remarkable divergences in adaptive strategies under drought and salinity, and the function of these strategies is compensatory. Leaf samples were collected from each type at the two sites in field. Sections of 2 cm × 2 cm were cut from the middle of fully expanded leaves and fixed in FAA. Leaf anatomical traits (e.g. stomatal density, leaf thickness and vessel diameters) were examined, and leaf mass per area (LMA), relative water content (RWC), proline, K+ and Na+ were measured. Compared with the gray green type (GG), the yellow green type (YG) with relative greater LMA and leaf thickness, lower stomatal density and index exhibited more obvious xerophil-liked anatomical traits, while higher RWC, proline, K+ and K+/Na+ for the GG type suggested that the ability of osmotic adjustment and salt tolerance of the GG type were stronger than the YG type. Stronger xerophytic anatomical traits were the supplementary strategies of the YG type for its low ability of osmotic adjustment and salt tolerance to drought and salinity.Concluding, there exist significant differences in anatomical and physiological strategies between the two ecotypes and the compensatory effects of these strategies enable the two ecotypes coexist at similar habitat. 相似文献
197.
杭嘉湖水网平原村域水环境污染及其负荷分析 总被引:1,自引:0,他引:1
文章以浙汀德清杨墩村为代表,分析评价了杨墩村河道的水质,估算了杨墩村不同污染源COD和氨氮的污染负荷,从而确定了污染控制和冶理的重点.杨墩村养殖业十分发达,规模化养殖和分散养殖同时存在,因此文章把规模化养殖作为点源污染,把分散养殖作为面源污染.然后再结合污染产生的实际方式和杨墩村的具体情况,对污染源进行研究分析.结果表... 相似文献
198.
Marina BeermannAuthor Vitae 《Journal of Cleaner Production》2011,19(8):836-842
Within modern society, business organizations have a co-evolutionary relationship with society and ecosystems. Business organizations face highly diverse risks which they have to recognize, reflect on and handle. Climate change and its impacts clarify the need for managing overall system risk. Research has shown that climate vulnerability of business organizations in the German food industry is characterized by impacts that, in particular, affect business organizations indirectly. Indirect climate change caused impacts are complex, uncertain and characterized by a high degree of unpredictability. They focus on the derived social, ecological, economic and cultural consequences of the direct physical impacts from a worldwide perspective. This paper shows that introducing resilience thinking helps to identify strategic risks and opportunities coping with climate change caused impacts in sense of corporate climate adaptation strategies. Furthermore, it is shown from a strategic management perspective that mitigation is a profound element of long term adaptation strategies. 相似文献
199.
基于污染物平衡分析的污水厂尾水补水城市内湖的优化运行研究——以昆明翠湖为例 总被引:1,自引:0,他引:1
针对污水厂尾水补水的城市内湖污染调控问题,提出了基于水量和污染物收支平衡分析的污染物净积累(NPA)模型,建立了污染物输入和输出量化计算方法.最后,以昆明翠湖为案例,在调查水体污染物输入和输出途径及水体自净量计算的基础上,选择COD、TN和TP为代表性污染物,开展了模型和计算方法的应用.结果表明,尾水补水是污染物输入的最主要途径,排水和渗漏是污染物输出的两个主要途径,COD在水体中的净积累程度较低,TN和TP的净积累比例分别达到42.9%和39.0%.以此为基础,本文提出了以调整补水和用水途径为主要手段的水体优化运行方案,并对方案实施后的预期效果进行了分析验证.本研究可为城市景观水体的污染物积累分析提供新方法和典型案例. 相似文献
200.
学校灾害教育现状调查研究及其启示 总被引:1,自引:0,他引:1
调查旨在了解学校灾害教育实施的实际情况,总结问题,提出相应策略。按照地理区划,分别选取了部分省市不同地区、不同学校的教师作为调查对象,回收有效问卷共计375份。调查结果表明:灾害教育实施现状不尽如人意,存在诸如"教师虽积极认同灾害教育价值,但教学中却较少主动实施"等问题,提出应构建灾害教育体系,形成长效机制,促进灾害教育开展。 相似文献