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1.
农村居民点多维形态空间格局与耦合类型   总被引:3,自引:0,他引:3  
农村居民点空间形态的系统认识与分类研究是乡村整治和科学实施乡村振兴的重要基础。以北京市平谷区为研究区域,从规模、结构和功能三个维度构建农村居民点形态识别指标,使用多因素综合评价法得到275个行政村的规模强度、结构合理度和功能协调度,借助ArcGIS和GeoDa依次对三者进行空间关联分析,进而基于三维特征划分出8种农村居民点耦合类型。结果表明:(1)平谷区农村居民点规模强度、结构合理度和功能协调度在空间上均存在空间集聚的正相关性,空间分布分别呈现“递进式”“圈层式”和“镶嵌式”格局。(2)平谷区农村居民点多维形态的地域差异性显著,全区62.8%的村庄表现为低强度,51.3%的村庄表现为结构不合理,61.4%的村庄表现为功能不协调。(3)平谷区以T1-S1-F2型(高强度—合理—不协调型)和T1-S2-F2型(高强度—不合理—不协调型)的农村居民点为主,两者共占农村居民点总量的60.1%,前者主要分布在距离城区较近的乡镇,后者主要分布在距离城区较远的北部、西南部和东部的山地丘陵区。(4)规模强度高、结构不合理、功能不协调的农村居民点类型是平谷区乡村协同发展的主要障碍,政策制度、技术工程、产业扶持等差别化治理模式是推进农村居民点可持续性利用和乡村振兴的关键。  相似文献   

2.
近年来频繁发生的城市洪水灾害,造成了巨大损失和严重影响。利用事故树分析法,以北京市"7·21"洪水事故为例,对城市洪水灾害成因进行了分析,构建了事故树、确定了最小割集,并对结构重要度进行了分析。结果表明:极端天气和城市雨岛效应是重要性最强的基本事件,排水不畅、人为因素是洪水灾害造成重大损失的重要症结。从增强预警、改善排水管网、减少硬化地面、疏浚河道等方面对解决城市洪水灾害的对策提出了建议。  相似文献   

3.
Coastal regions worldwide are during the process of rapid urban expansion. However, expanded urban settlements in land-sea interfaces have been faced with unprecedented threats from climate change related hazards. Adaptation to coastal hazards has received increasing attention from city managers and planners. Adaptation and land management practices are largely informed by remote sensing and land change modeling. This paper establishes a framework that integrates land change analysis, coastal flooding, and sea level rise adaptation. Multilayer perceptron neural network, similarity learning, and binary logistic regression were applied to analyze spatiotemporal changes of residential, commercial, and other built-up areas in Bay County, Florida, USA. The prediction maps of 2030 were produced by three models under four policy scenarios that included the population relocation strategy. Validation results reveal that three models return overall acceptable accuracies but generate distinct landscape patterns. Predictions indicate that planned retreat of residents can greatly reduce urban vulnerability to sea level rise induced flooding. While managed realignment of the coast brings large benefits, the paper recommends different mixes of adaptation strategies for different parts of the globe, and advocates the application of reflective land use planning to foster a more disaster resilient coastal community.  相似文献   

4.
Recent extreme weather events worldwide have highlighted the vulnerability of many urban settlements to future climatic change. These events are expected to increase in frequency and intensity under climate change scenarios. Although the climatic change may be unavoidable, effective planning and response can reduce its impacts. Drawing on empirical data from a 3-year multi-sectoral study of climate change adaptation for human settlements in the South East Queensland region, Australia, this paper draws on multi-sectoral perspectives to propose enablers for maximising synergies between disaster risk reduction and climate change adaptation to achieve improved planning outcomes. Multi-sectoral perspectives are discussed under four groups of identified enablers: spatial planning; cross-sectoral planning; social/community planning; and strategic/long term planning. Based on the findings, a framework is proposed to guide planning systems to maximise synergies between the fields of disaster risk reduction and climate change adaptation to minimise the vulnerability of communities to extreme weather events in highly urbanised areas.  相似文献   

5.
Slum dwellers response to flooding events in the megacities of India   总被引:3,自引:0,他引:3  
Megacities in developing countries are rapidly transforming places. Under the impetus of global change processes and consequent transformations at the environmental, social, cultural, political and economical scales; factors causing disasters and losses are changing every day. These changes are also altering society’s ability to respond to hazard events. This paper examines the response of slum dwellers who are the most vulnerable and marginal section of urban population and often located in places with high hazard risk with less or no means to reduce the impact of flood events. Marginal population groups in megacities suffer the negative consequences of large scale global change processes and do not benefit from the risk mitigation strategies adopted by city authorities. The paper therefore argues that people living in informal settlements instead have to employ a combination of structural means and complex networks of assistance to recover from floods. Based on the results deduced from data collected with the help of household surveys in the slums of Mumbai, the study demonstrates the types of coping strategies used by slum dwellers and the changing characteristics of these mechanisms under the influence of global change processes in megacities. Furthermore, results show that capacity to respond is not equally distributed among slum dwellers due to underlying socio cultural divisions and emerging economic and political constraints. The paper concludes that to address existing discrepancies in urban societies and within slum settlements, flood mitigation strategies will have to be (1) more inclusive of marginal population (2) sensitive to the limitations and scope of old and new social structures and (3) incorporate innovative networks of support to deal with the consequences of global change.  相似文献   

6.
农村居民点多功能空间格局与协调性优化模式   总被引:1,自引:1,他引:0  
随着城乡融合发展和农户需求的不断提高,探讨农村居民点多功能及其协调关系,是推进农村人居环境整治和乡村振兴的重要依据。以山东省王村镇为例,基于“识别—诊断—优化”的逻辑思路,从生活—生产—生态角度构建农村居民点多功能评价指标体系,利用空间自相关、协调度和障碍诊断等模型,剖析农村居民点多功能空间格局、协调关系及其障碍因子,进而提出农村居民点多功能提升与协调的优化模式。研究发现:(1)王村镇农村居民点总体上呈现出“生产功能较好,生活功能一般,生态功能较差”的特征,且不同功能具有显著的空间异质性;(2)王村镇农村居民点“三生”功能整体协调性相对较高,但协调类型存在明显的复杂性和不均衡性;(3)王村镇农村居民点“三生”功能协调性障碍因素表现为大体相似且个别村庄无障碍性,用地强度、交通条件、资源禀赋、基础设施建设和生态环境状况是农村居民点多功能高强度协调的主要障碍因素;(4)基于障碍因子组合提出的农村居民点多功能协调性优化模式,为可持续性乡村发展提供理论借鉴。  相似文献   

7.
Housing is not only one of the major sources of carbon dioxide (CO2) emissions, but it has been increasingly vulnerable to climate-induced disasters, particularly those sheltering the urban poor. Both mitigation and adaptation measures are therefore required for the design and construction of low-income housing to encourage low carbon development and improve resilience to disasters. As self-help housing—the common type of housing for the urban poor in developing countries—is usually built by ordinary people with participatory approach, it is crucial to develop a low-carbon and disaster-resilient assessment tool for assisting them in making informed decisions during planning process. The objective of this article is to propose a new approach for developing a low-carbon and disaster-resilient assessment tool for self-help housing (LoDAT-SH) by combining opinions from experts and community residents to assign weights, identify indicators, and establish benchmarks with the aim to develop a simple, relevant, and practical tool for non-expert users like self-help residents. The application of the proposed methodology to a case study of a developing country, Thailand, shows the ability of LoDAT-SH, which contains 45 indicators in the four categories of low carbon development, disaster resilience, community participation, and financial consideration, in enabling self-help residents to assess the performance of their housing design, identify potential measures to create a low-carbon and disaster-resilient housing, and prioritize such actions. To support the creation of a low-carbon and disaster-resilient housing as the mitigation and adaptation strategy for urban development at the global level, the study suggests that the methodology of LoDAT-SH should be replicated to develop a more comprehensive assessment tool applicable for the use in self-help housing design in other developing countries, which will house about 900 million of the urban poor by 2020.  相似文献   

8.
环境风险全过程评估与管理模式研究及应用   总被引:11,自引:2,他引:9       下载免费PDF全文
基于环境风险“全过程管理”与“优先管理”的理念,提出了环境风险全过程评估与管理的概念框架和理论体系,涵盖了风险源识别、受体易损性评估、环境风险表征、风险应急控制决策以及风险事故损失后评估等关键步骤.并以某化工园区企业为例,以硝基苯储罐塌陷为初始事件,采用蝴蝶结方法进行风险源识别,得到硝基苯储罐泄漏事件蝴蝶结,通过GIS空间分析方法揭示居民对地表水水源污染易损性的空间分异,分析结果不仅为事故安全防范与应急控制提供关键节点,而且有助于在日常风险管理中增强受体抗风险能力.  相似文献   

9.
The paper describes the “environmental recovering” of the Besòs River, a torrential river flowing through the urban area of Barcelona. An overview of river history and current problems and the aims and social constraints for the restoration are presented. After that, the design of a meandering low flow channel within the floodway is dealt with. Constructed wetlands to improve water quality were planned for the floodplain on both sides of this channel. Scale models, fixed-bed and mobile-bed, were then built to test the floodway conveyance and the risk of scour or deposition in it.  相似文献   

10.
综合遥感解译、宗地调查和入户问卷调查方法,研究黄淮海平原农区禹城市5个村庄的宅基地时空演变特征和不同退出标准的宅基地整治潜力和整治效果。研究结果表明:(1)改革开放以来,农村宅基地经历了剧烈扩张,调研村庄的宅基地平均扩张了3.7倍。2015年户均宅基地高达1.6宗,30.8%的农户存在“一户多宅”现象,28.5%的房屋被闲置或废弃。(2)2000年以前,调研村庄的宅基地空间扩张模式以飞地式为主,2000年后被填充式和蔓延式所取代。分村庄来看,宅基地空间扩张受到主要交通干线布局、土地资源禀赋和村庄初始布局等因素的影响。(3)调研村庄宅基地整治具有较大的理论潜力,可节约56%的村庄居住用地。基于两套退出标准方案的宅基地整治可分别节约26%和36%的村庄居住用地,但均与理论潜力存在较大差距。(4)未来宅基地试点改革亟需在推进转移人口市民化、建立宅基地退出补偿价值体系、探索退出的宅基地转化为集体经营性建设用地的办法等宏观体制机制推进,并在微观层面依据农户就业结构和土地资源禀赋分类施策。  相似文献   

11.
海洋藻华灾害对沿海地区的社会经济产生了相当大的影响。其中对滨海旅游经济及景观资源非使用价值(non-use value)的影响,无法从市场中得到直接评估。在对这部分非使用价值的评估中,条件评价法(contingent valuation method,CVM,也称条件价值法)是目前应用最为广泛的主要方法。该方法通过社会调查,以问卷方式收集被访者的信息,通过社会经济学的计算方法对目标资源的非使用价值受影响程度进行定量评价。本文利用CVM中的二分式实证问卷,以浒苔绿潮灾害对青岛滨海旅游资源非使用价值的影响为目标,调查在浒苔绿潮发生期内游客对改善滨海景观的支付意愿(WTP)信息,通过二值选择模型(Logit回归模型)计算,将浒苔绿潮灾害对青岛滨海旅游资源非使用价值的影响进行货币化评估,得出了该影响的大致范围,以直观的方式评价了浒苔绿潮灾害对青岛滨海旅游资源非使用价值的影响。这一方法可以作为海洋藻华灾害对社会经济影响评估方法的有益补充,为政府及相关组织对海洋藻华灾害的预防、治理以及更合理和有效的应急处置提供灾害经济影响部分的决策依据。  相似文献   

12.
This “Note from the field,” is an edited version of a policy brief summarizing the key findings from the first half of the Sustainable Consumption Research Exchange network (SCORE!) for the policy programs in the field of sustainable consumption and production (SCP). We recommend a framework for action to change to SCP that mentions the key domains to include food, mobility, and energy use/housing (the last two clearly related to urban development). It should use a systemic perspective on the SCP challenge and differentiate between developed, fast developing, and base of the pyramid economies. SCORE! focuses mainly on developed economies, and here we propose to differentiate between: (1) measures that fit with mainstream beliefs and paradigms. Here, governments could make operational agreements on implementation of instruments like green public procurement, stimulating ecodesign, etc. (2) Problems where a rough agreement on goals exists, but where change is radical, or means are uncertain, and hence planning difficult. Here, governments could foster visioning, experimentation, and support e.g. international collaboration in leapfrogging programs. (3) Problems that outright clash with the mainstream beliefs and paradigms. Here, governments could foster informed deliberation on the more fundamental issues related to markets, governance and growth.  相似文献   

13.
“无废城市”建设试点的提出标志着中国“无废社会”战略的实施和落实。采用物质流分析法量化了盘锦市2005—2018年的城市物质代谢;采用层次分析法和熵权法综合评价城市经济、资源、环境子系统的发展水平;借助系统动力学探究“无废城市”综合管理相较于其他发展模式对城市代谢系统优化的多方面潜力。结果表明:盘锦市物质投入产出具有“高投入、高排放、高隐藏流”特点;资源效益发展受限影响着整体城市代谢水平;在“无废城市”综合管理模式下,预计2025年资源产出率将在2018年基础上提高20.29%,环境效率提升4倍,极大地促进城市代谢系统资源、环境、经济层面的优化。  相似文献   

14.
本文建立了适用于高寒牧区的聚落布局适宜性评价体系,利用自组织神经网络(SOFM)对青藏高原藏北地区那曲县展开聚落布局适宜性评价,并评估其现状聚落布局的合理性,在此基础上提出其聚落未来重构的思路。结果表明:(1)那曲县对于聚落布局的适宜性整体较低,适宜性水平高于一般适宜的区域零散分布在海拔较低、地势低缓的河谷地区,仅占全县面积的12%。其他适宜性较低的区域占全县面积的88%,分布相对集中。不同乡镇对于聚落布局的适宜性差异显著。(2)那曲县现有的聚落空间占全县总面积的0.47%,为7594 hm2,其中分布在一般适宜及以上等级区的面积占聚落总面积的86.47%,而较不适宜、不适宜和禁建区内的聚落占比高达13.53%。那曲县聚落空间布局倾向于较高级别的适宜区,聚落用地适宜性条件较好的乡镇其布局合理性越高。那曲县局部聚落布局不合理的原因包括:缺失空间布局指引、村级行政区划欠佳、藏民对神山的宗教信仰和历史遗存的地域环境认同。(3)聚落的空间重构可推动生态移民、适度“村庄化”等要素的整合来实现。聚落的经济重构要建设由特色产业为基础的村镇系统、充分利用“点—轴”结构的辐射效应等结构要素的重组来实现。聚落的社会重构需要通过合理安排基础设施、增强藏族社会关系组织程度、提倡藏区优秀文化传承等优化功能的措施来实现。  相似文献   

15.
基于人居环境系统理论,运用层次分析法构建了一个包含四个一级子系统、九个二级子系统和三十六个基层指标的珠三角城市人居环境评价指标体系.选取1997年、2000年和2002年三个时间断面对珠三角城市人居环境进行测算.结果表明,珠三角城市人居环境系统工业化中期阶段特征明显,人居环境建设开始进入软环境主导时代,但发展的协调性和稳定性明显较差.同时人居环境的改善还面临着区域产业整合带来的严峻挑战.  相似文献   

16.
High genetic diversity is important for the functioning of large insect societies. Across the social Hymenoptera (ants, bees, and wasps), species with the largest colonies tend to have a high colony-level genetic diversity resulting from multiple queens (polygyny) or queens that mate with multiple males (polyandry). Here we studied the genetic structure of Trigona spinipes, a stingless bee species with colonies an order of magnitude larger than those of polyandrous honeybees. Genotypes of adult workers and pupae from 43 nests distributed across three Brazilian biomes showed that T. spinipes colonies are usually headed by one singly mated queen. Apart from revealing a notable exception from the general incidence of high genetic diversity in large insect societies, our results reinforce previous findings suggesting the absence of polyandry in stingless bees and provide evidence against the sperm limitation hypothesis for the evolution of polyandry. Stingless bee species with large colonies, such as T. spinipes, thus seem promising study models to unravel alternative mechanisms to increase genetic diversity within colonies or understand the adaptive value of low genetic diversity in large insect societies.  相似文献   

17.
上海市城市化进程中热环境响应的空间评价   总被引:1,自引:0,他引:1  
利用Landsat TM/ETM+ 遥感数据解译与反演得到上海市1997~2009年的土地利用/覆盖类型图及热岛强度分布图,并分析其演变趋势,引入温度-植被指数(TVX)并采用TVX空间法定量研究了以建设用地扩张、生态用地减少为特点的城市化过程引起的热环境效应.研究表明,1997~2009年,上海市人口呈现从中心城至郊区的流动趋势;热岛强度分布与城市化建设密切相关,呈现“葫芦串-葡萄串-摊大饼型”的蔓延模式;以牺牲生态用地为代价的建设用地扩张造成研究区域地表温度的上升及植被覆盖度的下降,其中林地减少所引起的热环境效应最大.研究可为城市规划决策过程中不同城市化空间的拓展情景提供其可能的环境响应结果,从而完善气候变化适应性对策,推进城市生态系统的可持续发展.  相似文献   

18.
村域尺度的多功能性评价对于揭示乡村空间由同质性向异质性分化发展具有重要意义。研究将探索乡村空间行为主体的活动变化作为多功能性评价的新思路,基于位置大数据反映的人类活动规律,构建了乡村空间居住、就业和消费三大功能指数,并就苏州市以农业和生态用地为主的陆巷村和众安桥村、建设用地为主的集善村和周泾村进行了实证分析。结果显示:具有相似区位条件和地域特征的乡村空间在工作日、双休日、节假日表现出不同的主导功能,可进一步划分为农旅结合型、兼业竞争型,以及现代园区型、城镇生活型。作为大数据方法在乡村地理学领域的一次有益尝试,研究结论可为乡村振兴战略提出的分类推进乡村发展提供科学借鉴。  相似文献   

19.
“乡村振兴”战略是解决城乡发展不协调、乡村发展不充分问题的重要抓手。居业协同作为乡村人居融合发展的高级形态,其程度能够反映乡村振兴的质量与成效。采用土地利用数据从结构和利用两个维度探索淮海经济区中心城市徐州三个尺度下的居业协同格局,结果表明:(1)徐州市土地在供给方面表现出居业失衡,宅基地供给相对于经营性建设用地优势明显;但由于使用中宅基地的空废,二者利用状态表现得更协同。(2)不同空间尺度下,居业协同状态有所差异,其中乡镇尺度居业空间关系较为稳定,基本维持相对平衡,本文认为乡镇是土地资源配置、实施乡村振兴战略的最佳尺度。(3)后续研究中,居业用地适宜的比例及农用地对居业协同的影响都需要进一步探索。  相似文献   

20.

Objective

To investigate factors involved in the decision to decline prenatal screening with noninvasive prenatal testing (NIPT).

Method

A questionnaire study was conducted among 219 pregnant women in the Netherlands who had declined prenatal screening with NIPT (TRIDENT-2 study). Respondents were selectively recruited from three hospitals and 19 midwifery practices, primarily located in or near socioeconomically disadvantaged neighborhoods. 44.3% of the respondents were of non-Western ethnic origin and 64.4% were religious.

Results

Most respondents (77.2%) found the decision to decline NIPT easy to make, and 59.8% had already made the decision before information about NIPT was offered. These respondents were more often religious, multigravida, and had adequate health literacy. The main reasons to decline NIPT were “I would never terminate my pregnancy” (57.1%) and “every child is welcome” (56.2%). For 16.9% of respondents, the out-of-pocket costs (175 euros) played a role in the decision, and the women in this group were more often nonreligious, primigravida, and had inadequate health literacy.

Conclusion

The primary factors involved in the decision to decline NIPT were related to personal values and beliefs, consistent with autonomous choice. Out-of-pocket costs of NIPT hinder equal access for some pregnant women.  相似文献   

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