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21.
通过构建老挝农业可持续发展水平评价指标体系,运用熵值法和层析分析法计算得出17个省域(直辖市)的人口系统、经济系统、社会系统、资源与环境系统和农业可持续发展水平综合得分,并对老挝省域农业可持续发展水平进行排序和分析。整体而言,中寮各省(直辖市)的农业可持续发展水平最高,下寮次之,上寮较低;老挝省域农业可持续发展水平整体差异不大,高水平和中低水平省域分布较为集中,中高水平和低水平省域相对分散,各等级空间分布形成由3个核心区域向周围递减的态势。最后指出,着力于打造3个核心农业发展区域,发挥其带动作用,并针对不同省域的农业发展状况采取相应措施,是逐步实现老挝农业可持续发展的有效途径之一。  相似文献   
22.
Four policies might close the gap between the global GHG emissions expected for 2020 on the basis of current (2013) policies and the reduced emissions that will be needed if the long-term global temperature increase can be kept below the 2 °C internationally agreed limit. The four policies are (1) specific energy efficiency measures, (2) closure of the least-efficient coal-fired power plants, (3) minimizing methane emissions from upstream oil and gas production, and (4) accelerating the (partial) phase-out of subsidies to fossil-fuel consumption. In this article we test the hypothesis of the International Energy Agency (IEA) that these policies will not result in a loss of gross domestic product (GDP) and we estimate their employment effects using the E3MG global macro-econometric model. Using a set of scenarios we assess each policy individually and then consider the outcomes if all four policies were implemented simultaneously. We find that the policies are insufficient to close the emissions gap, with an overall emission reduction that is 30% less than that found by the IEA. World GDP is 0.5% higher in 2020, with about 6 million net jobs created by 2020 and unemployment reduced.

Policy relevance

The gap between GHG emissions expected under the Copenhagen and Cancun Agreements and that needed for emissions trajectories to have a reasonable chance of reaching the 2 °C target requires additional policies if it is to be closed. This article uses a global simulation model E3MG to analyse a set of policies proposed by the IEA to close the gap and assesses their macroeconomic effects as well as their feasibility in closing the gap. It complements the IEA assessment by estimating the GDP and employment implications separately by the different policies year by year to 2020, by major industries, and by 21 world regions.  相似文献   

23.
Building damage maps after disasters can help us to better manage the rescue operations. Researchers have used Light Detection and Ranging (LiDAR) data for extracting the building damage maps. For producing building damage maps from LiDAR data in a rapid manner, it is necessary to understand the effectiveness of features and classifiers. However, there is no comprehensive study on the performance of features and classifiers in identifying damaged areas. In this study, the effectiveness of three texture extraction methods and three fuzzy systems for producing the building damage maps was investigated. In the proposed method, at first, a pre-processing stage was utilized to apply essential processes on post-event LiDAR data. Second, textural features were extracted from the pre-processed LiDAR data. Third, fuzzy inference systems were generated to make a relation between the extracted textural features of buildings and their damage extents. The proposed method was tested across three areas over the 2010 Haiti earthquake. Three building damage maps with overall accuracies of 75.0%, 78.1% and 61.4% were achieved. Based on outcomes, the fuzzy inference systems were stronger than random forest, bagging, boosting and support vector machine classifiers for detecting damaged buildings.  相似文献   
24.
Since the Paris Agreement was adopted in 2015, both national and subnational governments have been encouraged to submit Mid-Century Strategies, outlining how they would reach their deep decarbonization goals. However, research on the design and potential of these strategies has been very limited. To address this shortcoming, here we assess 13 such strategies – six national, seven subnational – in a comparative fashion. We find that the energy-economy-climate models underpinning these strategies are generally of high quality, though national jurisdictions generally performed better. However, most strategies are not plausible without significant changes to policy, and the industrial sector in particular presents a major limitation. The strategies are helpful in revealing this gap, but much works remains to be done for plausible mid-century decarbonization trajectories to become a reality. We also find that public input and societal participation in strategy building were a double-edged sword depending on the constellation of domestic preferences.
  • Governmental Mid-Century Strategies for deep decarbonization are underpinned by high-quality energy-economy-climate models

  • Governments’ proposed strategies require significant new policies, as even among jurisdictions that have an MCS, extant policies are insufficient to achieve deep decarbonization

  • No jurisdiction studied has yet put forward a plausible decarbonization policy for the industrial sector.

  • Public input and societal participation can be a double-edged sword: they can increase durability of the strategy but also enable opposing forces to mobilize against ambitious changes.

  相似文献   
25.
Cerastoderma edule and Mya arenaria are two common bivalve species in European waters. Longevity and maximum size are much greater in the latter species. Because comparison of species life-history strategies states that a long life span (i.e. high annual survival) generally goes with lower fecundity, we hypothesise that reproductive output would be lower in M. arenaria than in C. edule. In the present paper, we studied the reproductive strategies of these two species in an intertidal and a subtidal area of the western Dutch Wadden Sea, by following seasonal changes in absolute and relative weights of somatic and gonadal tissues in these bivalves. Starting of spawning was similar in the two species, around May, except for intertidal M. arenaria, which initiated spawning in August. Individual energy investment in reproduction was similar for the two species but, unlike M. arenaria, C. edule spawned completely, releasing all energy of gonadal mass in the form of gametes. Mya arenaria used the gonad not only for reproduction but also for storage. In the intertidal area, we found a trade-off between longevity and reproduction, i.e. maximum reproductive output (expressed as a proportion of body mass) was higher in C. edule than in M. arenaria. However, since body size is larger and life span longer in M. arenaria than in C. edule, mean lifetime reproductive output per individual must be higher in the first than in the latter. Based on the differences in reproductive strategies of these two species, we hypothesise that the negative effects of warming climate on bivalve population dynamics in the Wadden Sea will be stronger in C. edule than in M. arenaria.  相似文献   
26.
受流域来水来沙条件变化及河口大型工程建设的综合影响,长江口呈现新的冲淤格局,为预测未来演变趋势,本研究基于前期研究中建立的长江口年代际冲淤演变预测模型(Delft3D),未来情景考虑不同来沙量条件和相对海平面上升速率。预测结果表明,到2035年长江口整体以冲刷为主,口内河段主槽和浅滩边缘冲刷较明显,仅高滩局部淤积;到2050年口内河段保持净冲刷状态,拦门沙地区在现状来沙量条件下略有淤积,但在极端低来沙量条件下转变为净冲刷状态,海平面上升对拦门沙地区冲刷具有一定抵消作用,但不会使冲淤状态产生本质改变。本研究分析认为,长江口局部区域未来冲淤趋势可能对河口综合治理与保护产生不利影响,针对新格局条件下的滩槽河势稳定、重要洲滩保护、重大工程安全评估、冲刷致灾研判以及海堤防护标准再评估等方面提出了对策建议,可为新时期长江口综合治理与可持续发展提供参考。  相似文献   
27.
天津市地面沉降的特征及其危害   总被引:3,自引:0,他引:3  
天津是我国北方地面沉降最严重的城市之一,40余年的持续沉降不仅直接造成对安全高程、市政基础设施、房屋等建筑物的破坏,而且还通过安全高程的损失加剧了其他自然灾害的发生,使社会经济遭受严重损失.正确认识天津市地面沉降的特点及其危害,有利于控沉部门制定科学而有效的地面沉降减灾防灾政策和措施.基于对地面沉降所造成的危害分析和阐述,认为不合理开发地下流体资源是导致天津市地面沉降的主要原因,并提出相应预防和治理地面沉降的对策.  相似文献   
28.
3S技术在晚稻长势监测中的综合应用研究   总被引:12,自引:1,他引:12  
以江西省为试验区,探讨用RS-GIS-GPS技术监测作物长势的方法和途径。针对丘陵山区地形复杂、地块不成规模的情况,在GIS支持下,将数字高程数据、土地利用分类数据与GPS定位观测数据相结合,对NOAA/AVHRR进行判读,提取反映双季晚稻长势的植被指数,用该指数与GPS定位观测资料及地理信息数据进行监督分类监测苗情,并用迭代自组织分析法进行无GPS定位观测资料时相应时相的NOAA/AVHRR的长势监测。研究结果表明,选用的地理信息数据(数字高程数据、土地利用分类)与GPS定位观测资料相结合提高NOAA/AVHRR数据的利用效果是适合的和切实可行的。  相似文献   
29.
In order to extend the Tallinn temperature series backward in time, three different climate proxies were used. These were: the first day of ice break-up in Tallinn port, a proxy for the mean winter air temperature (December to March); the first day of ice break-up on the rivers in northern Estonia, a proxy for the beginning of spring; and, the first day of the rye harvest, a proxy for the mean air temperature in spring and summer (April to July). On the basis of these proxies the mean winter temperature could be extended back to the year AD 1500, and the spring and summer temperature back to 1731. The series of winter temperatures was analysed for long-term trends and variations on different timescales. The most striking feature is the warming of the winters from about the mid nineteenth century to the present. The warming is especially noticeable over the latest decades. The climate from the start of the series (AD 1500) to the mid nineteenth century was in general somewhat colder, and should be recognised as a part of the Little Ice Age, though the period was intercepted by warmer winters in the first half of the eighteenth century.  相似文献   
30.
为探究贵州省地震灾害风险薄弱环节,减轻地震灾害风险,以贵州省罗甸县为示范,采用地震危险性概率分析方法对各乡镇进行危险性分析,开展地震灾害承灾体现场抽样调查,通过层次分析法和问卷调查的方式,首次构建乡镇级别的地震灾害风险和减灾能力指标体系,评估各乡镇地震灾害综合指数和程度,计算各乡镇地震灾害风险指数,确定红水河镇为高风险区、罗悃镇为中风险区、木引等7个乡镇为低风险区,并从建筑物设防、地震地质灾害及水库地震等角度剖析罗甸县地震灾害特点,从农村危房改造、移民搬迁、地质灾害防护及交通等方面提出减小地震灾害风险的建议。  相似文献   
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