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81.
南方地质条件有四方面的特点:碳酸盐岩区与特提斯域有关,具有良好的含油气前景;叠置在碳酸盐岩区上的南、北两大前陆盆地带,对古生界原型盆地烃源岩的演化、油气藏形成和保存起到重要作用;南方海相地层具有丰富的烃源岩;后期多旋回构造运动,使南方海相油气系统变得十分复杂。南方油气选区评价的关键是保存条件,在含油气系统中“保存单元”是优选勘探目标的重要依据。“九五”期间,一要主攻中、下扬子区,获重大突破;二要积极做好滇黔桂地区三个盆地(南盘江盆地、楚雄盆地、十万大山盆地)的预探;三要进一步搞好区域评价。  相似文献   
82.
夏翠珍  廖杰  郭建军  刘慧  高扬 《中国沙漠》2019,39(3):107-116
政策工具是政府实施政策的手段。结合盐池县1983-2017年出台的生态治理政策,运用内容分析法,从政策工具视角,对盐池县生态治理政策的类型与变化进行了分析,并深入探讨其原因。结果表明:强制型和混合型政策工具占主导地位,其中,规制、直接提供、信息与劝诫、补贴与奖励4种工具使用频率最高,自愿型工具的使用还很缺乏。政策工具的运用受到中央政策的显著影响。以后应当开发更多可利用的政策工具,并对不同政策工具进行优化组合。通过本研究可深入了解生态脆弱区地方政府生态政策的政策工具使用情况,为生态脆弱区生态保护的政策工具选择与优化组合提供参考。  相似文献   
83.
A social scientist's perspective on the Census of Marine Life   总被引:1,自引:0,他引:1  
Over 300 natural scientists in 53 nations are taking part in the Census of Marine Life (CoML) to investigate what lived, what lives, and what will live in the oceans. The CoML is a scientific experiment that is exploring the limits of ocean science. The paper discusses the potential applications of CoML research and the mechanisms by which the potential benefits can be measured and preserved. I recommend developing and integrating policy advisory committees with the natural science activities to both maximize the benefits of the research and to avoid unintended consequences.  相似文献   
84.
This paper interprets differences in flood hazard projections over Europe and identifies likely sources of discrepancy. Further, it discusses potential implications of these differences for flood risk reduction and adaptation to climate change. The discrepancy in flood hazard projections raises caution, especially among decision makers in charge of water resources management, flood risk reduction, and climate change adaptation at regional to local scales. Because it is naïve to expect availability of trustworthy quantitative projections of future flood hazard, in order to reduce flood risk one should focus attention on mapping of current and future risks and vulnerability hotspots and improve the situation there. Although an intercomparison of flood hazard projections is done in this paper and differences are identified and interpreted, it does not seems possible to recommend which large-scale studies may be considered most credible in particular areas of Europe.
EDITOR D. Koutsoyiannis

ASSOCIATE EDITOR not assigned  相似文献   
85.
深圳市地理信息产业政策研究及建议   总被引:1,自引:0,他引:1  
深圳市2014年地理信息产业调查估算产值为50-60亿元,产业发展潜力具有很大的挖掘空间。有效的产业政策可以促进产业发展。为加快深圳地理信息产业发展,本文在对深圳市现有地理信息产业政策体系进行全面梳理和政策问题分析的基础上,开展促进深圳市地理信息发展的产业政策研究,提出深圳市地理信息产业优先发展方向、领域,并基于地理信息产业政策研究理论框架,给出具有针对性的政策完善建议。  相似文献   
86.
天津市海岸带环境的空间价值及其政策启示   总被引:1,自引:1,他引:1  
运用政策选择实验的方法, 对天津市沿海地区居民的政策需求进行了实证分析, 定量地考察了海岸带环境 的价值及其在不同地区和不同属性居民之间呈现的空间差异, 对不同类型经济开发的空间影响强度, 及海岸带开 发、防灾减灾和生态环境保护政策的效果进行了比较分析。主要研究结论包括, ①工业开发明显降低了居民的效 用, 说明在目前的产业结构和增长方式下, 工业开发是以生态环境的破坏为代价的, 需要通过产业和环境政策的统 筹和协调来解决工业开发与环境承载力的矛盾。相反, 渔业开发仍然会带来正面的综合效益, 因此, 渔业作为天津 沿海地区未来发展的重点产业之一是适宜的。②塘沽和汉沽地区海岸带环境的价值具有明显的空间差异性。例如, 在塘沽区, 港湾开发和娱乐业的发展给居民带来负面影响, 而在汉沽区, 这些开发所带来的影响不显著。因此, 应该 根据不同地区的实际情况确定海岸带管理政策的重点和目标, 并实施差别化的生态环境补偿政策, 对产业开发格 局进行调控。③不同类型人群对于海岸带政策的敏感性存在差异, 因此有必要根据各类人群的空间集聚程度制定 有针对性的政策。上述研究结论为海岸带管理的定量决策, 如凝炼各地区海岸带规划的目标、制定产业开发的生态 补偿政策提供了一定的科学依据。  相似文献   
87.
Constraining global average temperatures to 2 °C above pre-industrial levels will probably require global energy system emissions to be halved by 2050 and complete decarbonization by 2100. In the nationally orientated climate policy framework codified under the Paris Agreement, each nation must decide the scale and method of their emissions reduction contribution while remaining consistent with the global carbon budget. This policy process will require engagement amongst a wide range of stakeholders who have very different visions for the physical implementation of deep decarbonization. The Deep Decarbonization Pathways Project (DDPP) has developed a methodology, building on the energy, climate and economics literature, to structure these debates based on the following principles: country-scale analysis to capture specific physical, economic and political circumstances to maximize policy relevance, a long-term perspective to harmonize short-term decisions with the long-term objective and detailed sectoral analysis with transparent representation of emissions drivers through a common accounting framework or ‘dashboard’. These principles are operationalized in the creation of deep decarbonization pathways (DDPs), which involve technically detailed, sector-by-sector maps of each country’s decarbonization transition, backcasting feasible pathways from 2050 end points. This article shows how the sixteen DDPP country teams, covering 74% of global energy system emissions, used this method to collectively restrain emissions to a level consistent with the 2 °C target while maintaining development aspirations and reflecting national circumstances, mainly through efficiency, decarbonization of energy carriers (e.g. electricity, hydrogen, biofuels and synthetic gas) and switching to these carriers. The cross-cutting analysis of country scenarios reveals important enabling conditions for the transformation, pertaining to technology research and development, investment, trade and global and national policies.

Policy relevance

In the nation-focused global climate policy framework codified in the Paris Agreement, the purpose of the DDPP and DDPs is to provide a common method by which global and national governments, business, civil society and researchers in each country can communicate, compare and debate differing concrete visions for deep decarbonization in order to underpin the necessary societal and political consensus to design and implement short-term policy packages that are consistent with long-term global decarbonization.  相似文献   
88.
89.
通过对成都市新津县3个城乡统筹试点区农民安置区的实地调查,构建了基于客观建设条件与主观满意度的安置区人居环境指标体系,运用模糊综合分析法对主客观两方面因素进行综合分析,得出居民对安置区的满意度及安置区建设条件评价。结果表明:袁山社区居民人居环境满意度及客观建设条件得分最高,其在安置区建设、安置区政策、居民社会经济等方面均优于其他两个社区。对成都市新津县"挂钩"试点区农民安置区的人居环境满意度评价,能从侧面反映出成都市推行"挂钩"政策的具体情况,客观衡量政策实施的优劣程度,发现政策推行过程中的主要问题,对推进区域城乡统筹具有一定的借鉴意义。  相似文献   
90.
Public service systems, such as emergency health care, police or fire brigades, are critical for day-to-day functioning of the society. To design and operate these systems efficiently much data needs to be collected and properly utilised. Here, we use the OpenStreetMap (OSM) data to model the demand points (DPs), which approximate the geographical location of customers, and the road network, which is used to access or distribute services. We consider all inhabitants as customers, and therefore to estimate the demand, we use the available population grids. People are changing their location in the course of the day and thus the demand for services is changing accordingly. In this paper, we investigate how the used demand estimate affects the optimal design of a public service system. We calculate and compare efficient designs corresponding to two demand models, a night-time demand model when the majority of inhabitants rest at home and the demand model derived from the 24-hour average of the population density. We propose a simple measure to quantify the differences between population grids and we estimate how the size of differences affects the optimal structure of a public service system. Our analyses reveal that the efficiency of the service system is not only dependent on the placement strategy, but an inappropriate demand model has significant effects when designing a system as well as when evaluating its efficiency.  相似文献   
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