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811.
812.
我国新时期生态保护修复总体战略与重大任务 总被引:2,自引:2,他引:0
生态保护修复是美丽中国建设的重大任务,是加快推进生态文明建设的优先行动,是推动生态产品价值实现的重要基础。近年来,我国生态保护修复取得显著进展,但生态系统本底脆弱、保护修复基础薄弱、管理机制不协调等问题依然突出。在大力推进生态文明建设的新的历史时期,面对百年未有之大变局,我国生态保护修复工作所面临的形势更加严峻,与实现国家生态治理体系和治理能力现代化的要求依然存在较大差距,尚难以满足人民日益增长的优质生态产品需要。本文在总结近年来我国生态保护修复主要进展基础上,分析了未来一段时期生态保护修复面临的问题与挑战,提出新时期生态保护修复应以习近平生态文明思想为统领,以提升生态系统服务功能、协同改善生态环境质量、维护国家生态安全为核心,探索构建生态保护修复与污染防治统筹推进机制,强化监管制度设计、示范样板引领、体制机制创新,加快实现山水林田湖草整体保护、系统修复、综合治理,筑牢美丽中国生态根基。 相似文献
813.
近年来在乡村振兴战略实施背景下,乡村旅游在发展农村经济中的作用更加凸显。促进乡村旅游的健康发展和乡村农户生计的持续改善是当前学术界讨论的重要话题。现有研究表明,可持续生计框架中客观环境影响作用是可持续旅游生计研究的热点方向,但可持续生计框架外其他主观因素对生计策略转变影响的动态定量考量却较为空缺。本研究在乡村旅游背景下探讨政府信任度对农户生计策略转变意愿影响机制,引入居民参与度、居民支持度和生活满意度多重链式中介作用,通过结构方程模型对山东省乡村旅游地进行定量分析,并对特定路径间中介作用进行比较。实证研究结果显示:①政府信任度对居民参与度和居民支持度具有正向影响,居民支持度正向影响居民参与度。②居民参与度和居民支持度均正向影响生活满意度。③生活满意度对农户生计策略转变意愿产生正向影响。这表明在居民支持度、居民参与度和生活满意度多重链式中介作用下,政府信任度对生计策略转变意愿具有间接影响。因此,为了助推乡村振兴,实现乡村旅游和农户生计的可持续,应发挥政府作用,从政策实施、旅游市场监控、完善基础设施建设等方面提高政府信任度,培养农户的主人翁意识,引导农户融入乡村旅游发展过程中,提高生活满意度,增强农户生计策略转变意愿。 相似文献
814.
Marina Povitkina 《环境政策》2018,27(3):411-432
Previous research has shown that democracies exhibit stronger commitments to mitigate climate change and, generally, emit less carbon dioxide than non-democratic regimes. However, there remains much unexplained variation in how democratic regimes perform in this regard. Here it is argued that the benefits of democracy for climate change mitigation are limited in the presence of widespread corruption that reduces the capacity of democratic governments to reach climate targets and reduce CO2 emissions. Using a sample of 144 countries over 1970–2011, the previously established relationship between the amount of countries’ CO2 emissions and their level of democracy is revisited. It is empirically tested whether this relationship is instead moderated by the levels of corruption. The results indicate that more democracy is only associated with lower CO2 emissions in low-corruption contexts. If corruption is high, democracies do not seem to do better than authoritarian regimes. 相似文献
815.
Adrianne Kroepsch Elizabeth A. Koebele Deserai A. Crow John Berggren Juhi Huda Lydia A. Lawhon 《Environmental Communication: A Journal of Nature and Culture》2018,12(1):132-147
Wildfire may be the clearest example to date of a socio-natural hazard that is being exacerbated by climate change, making wildfire an essential lens through which to investigate learning and adaptation in the Anthropocene. Here, we study discourse about simultaneous and recurring catastrophic wildfires in Colorado newspapers. We find that the wildfires’ anniversaries served as opportunities for critical reflection on hazard causality and mitigation in local media, particularly the first anniversary and especially for a community that experienced two catastrophic wildfires in a row. Two mediated prospective memory practices—invoking hindsight as foresight and recognizing a new normal—contributed to this discourse. However, learning and adaptation discourse faded in local media at later anniversaries. These findings contribute to learning and adaptation scholarship by connecting the concept of mediated prospective memory to disaster-related media studies and attending to the intricacies of anniversary commemoration under circumstances of simultaneous and recurring disasters. 相似文献
816.
Jung-Tang Hsueh 《International Journal of Green Energy》2017,14(14):1209-1220
This study presents processes to evaluate the optimal collecting strategy (CS) in reverse logistic (RL) for the downstream part of the Taiwan photovoltaic industry (TPI). It combines the analytic hierarchy process (AHP) with the technique for ordering preference by similarity to the ideal solution (TOPSIS). The criteria and sub-criteria were initially established to assess the related benefits, opportunities, costs, and risks (BOCR). AHP was then used to obtain the weightings of the criteria and sub-criteria and TOPSIS was used to rank the optimal collection strategy in terms of its overall evaluation criteria. The AHP and TOPSIS method provides decision makers with a valuable reference for assessing the optimal collection strategy of TPI downstream. The results of the study should provide decision makers in the downstream TPI with academic support and valuable guidance for evaluating their collection program and obtain optimal strategies for administering RL practices. 相似文献
817.
简述目前环境监测发展的基本形势,回顾了江苏省环境监测发展历程,分析目前江苏省环境监测面临的挑战和压力,提出了江苏环境监测战略目标和战略重点,并对江苏环境监测发展采取的战略措施提出了建议。 相似文献
818.
Monitoring Nitrogen Dioxide and its Effects on Asthmatic Patients: Two Different Strategies Compared
Massimiliano Panella Vania Tommasini Marco Binotti Lucio Palin Gianni Bona 《Environmental monitoring and assessment》2000,63(3):447-458
Objectives: To develop a `methodologyassessment' to evaluate the strengths and theweaknesses of two different epidemiological approachesand to identify the best suited monitoring strategy tomeasure the effects of `normal levels' of nitrogendioxide exposure on the health of an urban population.Methodology: all exposures to nitrogen dioxidewere determined with passive samplers, each samplerconsisting of 3 measuring Palmes tubes. In the firststudy the nitrogen dioxide exposure was assessed in 23school children (11 asthmatic and 12 non asthmatic).Children wore samplers for a week and parallelmeasurements were made in their kitchens, in bedroomsand outside their homes. The second study consisted ina case-control study where the relative risk ofhospital admission was calculated considering nitrogendioxide levels in a city of northern Italy. 110asthmatic patients were compared to a control group of 5322 people.Results: Personal sampler measurementshighlighted significant differences in exposure when nitrogen dioxide atmospheric levels were compared inasthmatic and healthy children (p<0.05). No otherparameters were significant in the two groups. Asignificant action of atmospheric nitrogen dioxide onhospital admission was demonstrated (p<0.01).Conclusions: Although a cause-effect relation assuch cannot be identified, the studies show a relationbetween the exposure to nitrogen dioxide and thepresence of adverse effects on people's health.However the `disadvantage' is for subjects withasthmatic pathologies, compared to the others. Tomanage this problem most effectively, a combinedapproach with the activation of specific personalmonitoring campaigns of the subjects with verifiedrisk seems necessary. This requires `reading' the dataresulting from most extensive and up to dateinformation systems, capable of a thorough controlboth of the living environment and of the clinicaloutcome of the whole population. 相似文献
819.
不同供氧策略对SBBR反应器实现短程硝化厌氧氨氧化的影响分析 总被引:1,自引:1,他引:0
以氨氮浓度较高的垃圾渗滤液为处理对象,分析研究了不同供氧策略对SBBR反应器实现短程硝化厌氧氨氧化的影响.在4种不同供氧策略(a、b、c和d的总供氧时间分别为16h、12h、12h和8h;好氧/厌氧交替频率分另U为4h/2h、3h/3h、2h/2h和2h/4h)下同步启动反应器,保持各反应器内环境温度为(30.0±4-0.5)℃,并控制曝气阶段溶解氧(DO)浓度为(1.2±0.1)mg·L-1.实验结果表明,反应器内的微生物经过124d的驯化和增殖,具有一定的脱氮能力,但是效果不同,其中,采用总供氧时问为12h,好厌氧交替频率为2h/2h供氧策略的反应器c效果最好,氨氮去除率达到96.6%左右,而且抗氨氮冲击负荷的能力最强,最大的氨氮容积负荷为0.186 g·(L·d)-1;在曝气阶段由于DO浓度的限制,亚硝酸盐出现积累;缺氧阶段,由于厌氧氨氧化细菌和反硝化细菌的协同作用,亚硝酸盐氮和氨氮同时被去除,且没有硝酸盐的积累.从4个反应器和渗滤液原水中提取细菌总DNA,通过PCR-DGGE技术获得DGGE图谱.分析图谱中各泳道的条带数目和条带亮度、各泳道间的相似性系数C,值,结果表明,不同供氧策略对反应器内的细菌多样性和种群结构产生了较大影响. 相似文献
820.
本文在深入分析大连市金州区发展外向型农业优势的基础上,探讨了该区外向型农业空间发展的原则和指导思想,初步界定了基地空间范围及未来的发展布局,为金州区外向型农业空间发展战略提供了理论依据。 相似文献