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991.
水环境是城市形成的过程中不可缺少的要素。文章从水环境对城市发展的重要作用出发,提出亲水生态城市的概念以及亲水生态城市的建设模式,为城市的发展提供参考意见。 相似文献
992.
中国1997-2006年可持续发展动态测度分析 总被引:1,自引:1,他引:1
利用生态足迹分析法对中国1997-2006年的生态足迹与生态承载力进行核算,从而定量测度近10年来中国的可持续发展状况,根据结果对生态足迹的供给和需求进行分析并提出相应的建议和对策.结果表明:10年来,中国的生态足迹快速增长,由1997年的1.287 hm2增长到2006年的1.941 hm2,人均生态赤字从1997年的0.596 9hm2增长到2006年的1.267 0 hm2,自然生态系统处于不可持续的发展状态; 在生态足迹的构成中,能源和水域的生态赤字最为严重,远未满足供需平衡;此外,万元GDP占用生态足迹从1997年的2.014 8 hm2降低到2006年的1.209 8hm2,说明中国资源利用效率提高较快,经济增长方式在向良性发展. 相似文献
993.
Community action has an increasingly prominent role in the debates surrounding transitions to sustainability. Initiatives such as community energy projects, community gardens, local food networks and car sharing clubs provide new spaces for sustainable consumption, and combinations of technological and social innovations. These initiatives, which are often driven by social good rather than by pure monetary motives, have been conceptualised as grassroots innovations. Previous research in grassroots innovations has largely focused on conceptualising such initiatives and analysing their potential for replication and diffusion; there has been less research in the politics involved in these initiatives. We examine grassroots innovations as forms of political engagement that is different from the 1970s’ alternative technology movements. Through an analysis of community-run Energy Cafés in the United Kingdom, we argue that while present-day grassroots innovations appear less explicitly political than their predecessors, they can still represent a form of political participation. Through the analytical lens of material politics, we investigate how Energy Cafés engage in diverse – explicit and implicit, more or less conscious – forms of political engagement. In particular, their work to “demystify” clients’ energy bills can unravel into various forms of advocacy and engagement with energy technologies and practices in the home. Some Energy Café practices also make space for a needs-driven approach that acknowledges the embeddedness of energy in the household and wider society. 相似文献
994.
Justin D. Burdine 《Local Environment》2018,23(2):198-219
Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered. 相似文献
995.
996.
以黑龙江省为例,在脱贫攻坚视角下,选取林业产业总产值、造林面积、林业固定资产投资完成额、林业系统年末从业人数、林业产业结构比例5个有关森林生态产品供给效率的测算指标,通过DEA模型对黑龙江省2001—2017年森林生态产品供给效率进行测算,并运用Tobit模型对该效率的影响因素进行分析。结果表明:(1)黑龙江省森林生态产品供给效率的综合效率总体良好。(2)森林生态产品供给效率的综合效率与规模效率密切相关。(3)林业旅游与休闲服务收入比重和林业生态建设实际到位金额与供给效率显著正相关,而火灾次数与供给效率显著负相关。 相似文献
997.
998.
乙酸铵交换法测定土壤阳离子交换量的不确定度评定研究 总被引:1,自引:0,他引:1
采用乙酸铵交换法测定土壤阳离子交换量,并分析了测量过程中不确定度的来源:样品和标准物质的称量,容量瓶、移液管和滴定管的体积,以及测量的重复性等.在此基础上对各不确定度分量进行评定,并计算得到合成不确定度和扩展不确定度.最后提出了在测定过程中减小不确定度的有效途径,认为乙酸铵交换法测定土壤阳离子交换量的结果不确定度主要来源于重复性测定,增加测量次数可以减小重复性的不确定度,从而降低测定不确定度.当土壤中阳离子交换量为22.5 cmol(+)/kg时,扩展不确定度为1.0 cmol(+)/kg,置信水平为95%. 相似文献
999.
Junqiang Xia Zhengbing Wang Yanping Wang Xin Yu 《Journal of the American Water Resources Association》2013,49(1):114-131
Xia, Junqiang, Zhengbing Wang, Yanping Wang, and Xin Yu, 2012. Comparison of Morphodynamic Models for the Lower Yellow River. Journal of the American Water Resources Association (JAWRA) 1‐18. DOI: 10.1111/jawr.12002 Abstract: Significant channel adjustments often occur during flood seasons in the Lower Yellow River (LYR), and it is a challenging work to accurately simulate the morphodynamic processes in the LYR using numerical models. A comparison of two morphodynamic models (Delft3D and 2DLLCDM) for the LYR is presented herein to identify critical improvements for these models. The concepts of these models are first compared with each other. The models were then used to simulate the processes of flood routing, sediment transport, and morphological changes occurring in a braided reach of the LYR. The differences were investigated between the simulated results from these models and corresponding field measurements, and the results indicate that: (1) the hydrodynamic processes calculated by both models agree closely with the measurements if an appropriate Manning’s roughness coefficient is used; (2) the concentrations of suspended load at the downstream boundary calculated by the models agree reasonably with the observed data; and (3) the predicted cross‐sectional profiles obtained from these models do not correspond well with the measurements. Based on these findings, the weak aspects of the models are clarified, and three critical improvements are recommended, including: (1) the development of roughness predictor; (2) the refinement of graded sediment transport capacity formulation; and (3) the consideration of bank erosion module. These improvements need to be implemented in the future. 相似文献
1000.
Ryo Fujikura 《Local Environment》2013,18(4):469-482
Social scientists have described Japan's urban anti-pollution protests in the 1960s as a national phenomenon. However, in Kitakyushu, Japan's most polluted industrial city at that time, no distinct citizens' movement developed. Because local politics and economics were so dominated by large industry, its citizens were reluctant to directly challenge these industries. Instead, local women's groups studied local pollution problems and presented their general findings to the public. These activities raised public awareness and resulted in increased support for local leftist politicians because leftist administrations had succeeded in cutting pollution in their cities. Kitakyushu's conservative mayor and local industry both became concerned that leftists would win the next local elections if pollution was not reduced. Thus the municipal government utilised scientific pollution data and prepared individualised pollution reduction recommendations in sulphur oxide pollution control agreements, which were accepted and complied with by all local industries. The result was a significant reduction in air pollution without the need for active intervention from Kitakyushu's citizenry. Cientificos sociales han descrito las protestas anti-polución urbana de Japon en los años 60 como un fenómeno nacional. Sinembargo, en Kitakyushu, ciudad industrial japonesa más polucionada en ese tiempo, no se desarrollóningún movimiento ciudadano evidente. Debido a que las políticas locales y económicas eran dominadas por la gran industria, sus ciudadanos no estaban dispuestos a retar directamente estas industrias. En lugar de eso, grupos locales de mujeres estudiaron problemas locales de polución y presentaron sus resultados al público. Estas actividades despertaron conciencia pública y resultaron en el incremento del apoyo para políticos izquierdistas locales debido a que las administraciones izquierdistas habían triunfado en la reducción de la polución en sus ciudades. El alcalde conservador y la industria local de Kitakyushu empezaron a preocuparse que los izquierdistas ganarían las próximas elecciones locales si la polución no era reducida. Asíque, el Gobierno Municipal utilizó información científica sobre polución y preparó recomendaciones de reducción de polución individualizada en acuerdos de control de polución en oxído sulfurico, los cuales fueron aceptados y obedecidos por todas las industrias locales. El resultado fue una significativa reducción en la polución del aire sin la necesidad de la intervención activa de parte de la ciudadania de Kitakyushu. 相似文献