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101.
以30个省会城市为研究对象,从宏观尺度揭示中国城市的网络团购市场供给规模与需求潜力的协调性特征。结果表明:团购市场供给规模较大的城市主要集中在中国东部和西部地区;东部地区城市的供给规模和需求潜力的协调发展程度整体较好,供需失调现象明显的城市主要集中在西北地区;团购市场供给规模及其与需求潜力的协调性均遵循以经济发展水平为标尺的等级式扩张路径。餐饮、娱乐和旅游酒店3类团购市场供给规模相对需求潜力表现出了较明显的过剩现象。城市经济发展水平是团购市场供需协调发展的根本动力,团购市场供给规模和需求潜力水平是团购市场协调发展的直接动力。  相似文献   
102.
基于旅游公平理论,从政府民生活动对当地居民的影响角度提出了"旅游民生感"概念和实际民生感、期望民生感、比较民生感3个测量维度,通过问卷调研数据和对应分析方法进行了实证研究。结果发现:民族地区居民年龄越大对其实际民生感越满意,而工人和中等学历居民则倾向于不满意;对于期望民生感,学生、工人、中低收入和距离景区近的人群趋于不满意;农民的比较民生感趋于满意,而企事业人员、中低收入者、居住地与景区距离居中的人群和高学历人群则对比较民生感趋于不满意。最后,从统筹兼顾、社区公平和弱势群体改善民生诉求3个方面提出了政策建议。  相似文献   
103.
“十二五”期间,河南省深部探矿工程技术研究中心根据专业学科特点和环境资源新形势,紧密结合生产实际,围绕“加强科技创新能力,服务经济社会发展”的思路和原则,积极开展系列自主创新活动。将空气潜孔锤、气举反循环、孔底螺杆马达、石油钻井、液动潜孔锤、绳索取心等技术根据地层特点进行组合,实现了多工艺钻探技术。在国家应急抗旱救灾、地热清洁能源勘查、复杂地层钻探和钻探相关标准化建设等方面取得了显著成效。结合环境形势和地质工作新常态、利用大地质理念提出了民生地质(工业地质、农业地质、灾害地质、医学地质、新能源地质等)新概念和“十三五”钻探工作的新思路。  相似文献   
104.
China is home to nearly half of the world’s 50,000 large dams, which provide irrigation, flood protection, and hydroelectricity. Most of these projects involve substantial population displacement, which can disrupt social capital, the webs of interdependence and support that community members maintain with one another through relationships of trust and reciprocity. We use new empirical evidence to examine the association between dam-induced displacement and social capital in China and interpret our findings in the context of social–ecological resilience theory. Our focus is on agricultural households on the Upper Mekong River, where four large hydropower dams have been constructed over the past twenty years.Our broad finding is that resettlement is associated with diminished social capital, as measured by two key indicators: inter-household exchange of financial resources, and inter-household exchange of agricultural labor. These effects differ across the four dam sites in the study based on local economic conditions and changes in resettlement policy. We find that population resettlement is associated with markedly lower levels of agricultural labor exchange. In an economically under-developed setting, this reduces the depth and breadth of social support that agricultural households rely on to produce crops for subsistence and income. This in turn diminishes social–ecological resilience because social capital is a key factor that helps agricultural or resource-dependent communities manage risk and adapt to changes and stressors.We consider the policy implications of our findings in the context of scientific and industry efforts to minimize social harm, promote economic vitality, and improve the sustainability of hydropower as a form of renewable energy.  相似文献   
105.
San Francisco is now widely considered to be the most important city in the world for the location of new technology start-up firms, especially high valuation “unicorns,” and is increasingly seen as both a locational and metaphorical extension of Silicon Valley. In this paper, I trace some of the political strategies and tensions that have accompanied the city’s prominence in this area, and in particular the distinctive role of technology and venture capital in the political economy of urban development. The paper has four empirical sections. It describes (1) the political machinations surrounding the 2011 and 2015 municipal elections, which saw the election of Ed Lee as Mayor with significant support from individual technology investors such as Ron Conway and Marc Benioff, and accompanied by various “tech-friendly” policy shifts; (2) the foundation of the “tech chamber of commerce” sf.citi as a means of enhancing the policy influence of the tech industry in San Francisco; (3) the introduction of a low taxation regime in the city’s Central Market area that has attracted technology companies such as Twitter as tenants; and (4) the urban policy tensions associated with the evolution of new “sharing economy” firms such as Uber and Airbnb, which have aggressively challenged municipal regulations in the taxi and property rental fields. Throughout these machinations, we can see a reshaping of capital fractions, with venture and angel capital increasingly involved in reengineering the labor, housing, and public transport markets of the city in order to circumvent the accumulation problems that tech investors had suffered in the earlier dot.com failures.  相似文献   
106.
生计多样化背景下种植业非点源污染负荷演变   总被引:3,自引:1,他引:2  
钟建兵  邵景安  杨玉竹 《地理学报》2016,71(7):1201-1214
依托三峡库区典型村农户访谈数据,基于收益最大目标决策框架,设定农村转型发展中3种农户生计类型情景:农业主导生计、兼业转向生计和非农主导生计,解析种植业产污负荷随主导生计非农转向的演变特征,探讨主导生计类型转向的动力机制。结果表明:① 样区耕地经营现状呈自耕、流转与撂荒并存的多元化发展格局,且表现出“入”小于“出”的特征,不同农户家庭类型间实际人均耕种规模为“半劳动力家庭”>“无劳动力家庭”>“劳动力家庭”;② 种植业单位面积产污负荷中,“半劳动力家庭”最高,“劳动力家庭”次之,“无劳动力家庭”最低,“劳动力家庭”内部又随劳动力人数增加呈先增再减趋势;③ 样区农户生计类型由农业主导向非农主导转型过程中,种植业产污负荷最大减幅达72.01%,兼业转向生计情景下削减幅度为19.61%~29.85%,非农主导生计情景下减幅为35.20%~72.01%,但TN、TP的减量特征并不一致;④ 劳动力配置与生计来源“非农化”促使农户主导生计类型向非农转化,生计非农演变的潜在农户收入/福祉权衡亦驱使生计决策转向非农化,不同农户家庭类型对生计转向的敏感程度表现为“劳动力家庭”>“半劳动力家庭”>“无劳动力家庭”;⑤ 在新型城镇化快速推进和创新新型工业体系构建过程中,山区农户生计类型进一步向非农转变,而这一过程又将促使种植业产生的污染负荷量进一步减少,要大幅削减种植业产污负荷,就必须制定有助于山区农户生计非农化的调控对策。  相似文献   
107.
人口与土地是城镇化的重要组成部分,分析二者之间状态演化对促进城市健康发展具有重要意义。在界定人口城镇化与土地城镇化二者概念基础上,基于人口构成、人口素质、人口生活、城镇规模、城镇投入、城镇产出等构建评价指标体系,并通过耦合协调模型对省会型城市南昌市2002~2011年两者之间的协调关系进行测度和分析,结果表明:人口城镇化指数与土地城镇化指数呈波动变化并持续上涨,城镇发展由土地滞后型向人口滞后型转变;人口城镇化与土地城镇化的协调状态由失调衰退区向过渡协调区演进,发展类型则由高度不协调状态向勉强协调状态过渡。在此基础上分析了南昌市人口城镇化速度滞后于土地城镇化速度的原因,指出两者关系主要受到城市发展外在制度与内在基础的共同作用,并认为构建人口与土地城镇化双重优化路径是协调人口城镇化与土地城镇化同步发展的有效途径。  相似文献   
108.
Multiple ecosystem services (ES) can respond similarly to social and ecological factors to form bundles. Identifying key social-ecological variables and understanding how they co-vary to produce these consistent sets of ES may ultimately allow the prediction and modelling of ES bundles, and thus, help us understand critical synergies and trade-offs across landscapes. Such an understanding is essential for informing better management of multi-functional landscapes and minimising costly trade-offs. However, the relative importance of different social and biophysical drivers of ES bundles in different types of social-ecological systems remains unclear. As such, a bottom-up understanding of the determinants of ES bundles is a critical research gap in ES and sustainability science.Here, we evaluate the current methods used in ES bundle science and synthesize these into four steps that capture the plurality of methods used to examine predictors of ES bundles. We then apply these four steps to a cross-study comparison (North and South French Alps) of relationships between social-ecological variables and ES bundles, as it is widely advocated that cross-study comparisons are necessary for achieving a general understanding of predictors of ES associations. We use the results of this case study to assess the strengths and limitations of current approaches for understanding distributions of ES bundles. We conclude that inconsistency of spatial scale remains the primary barrier for understanding and predicting ES bundles. We suggest a hypothesis-driven approach is required to predict relationships between ES, and we outline the research required for such an understanding to emerge.  相似文献   
109.
This case study on the Borkena wetlands in north‐eastern Ethiopia tells, through the voices of the inhabitants, the story of the occupation and management of an area where agro‐pastoralists (Urrane) and farmers have progressively settled. It shows how different policy changes and natural disasters have transformed the type of peoples' livelihoods and land use patterns in the wetland. It tells the history of relationships between smallholder peasants, irrigation farmers, commercial farms, and the Urrane, where conflicts as well as collaboration developed, and it shows how different stakeholders behave and consider their own situation. The study also reveals that development intervention by World Vision Ethiopia (WVE) had mixed impact on peoples' livelihoods in the wetland: sedentary peasants have benefited while the Urrane have been adversely affected. The main issue is the marginalization of pastoralists, with the denial of their traditional land use rights by three successive regimes and administrations. Any solution to the cohabitation of the different groups and livelihoods will have to address the issue of land rights for the pastoralists and promote the fair participation of all stakeholders in the future management of the wetlands. Good governance and the competence of the state actors at local levels are the crucial issues for the realization of the suggested solutions.  相似文献   
110.
Food insecurity and increasing impoverishment of the masses in developing countries constitute a challenge for social scientists, whose theories have tried to catch up with the enormous challenges of diversity, dynamism and the impacts of the forces of­‘glocalisation’. This article reviews the efforts in the social sciences towards understanding food insecurity and suggests a framework incorporating dynamism and diversity in rural communities in the research process. Structural changes affecting peasant economies and peasant responses make existing general theories inappropriate without a contextual treatment. Insights from existing theories are used to construct a livelihood vulnerability framework for researching and understanding food insecurity in rural areas.  相似文献   
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