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911.
社会空间是社会过程与空间过程的有机统一,把握山区农村社会空间的形成、演化,可以为通过空间规划推动乡村振兴提供新的切入点。在对陕西省太白县、柞水县、商州区三个秦岭山区县的农户进行入户调查、县乡调研和文献分析的基础上,采用统计占比分析和相关分析研究山区农村社会的特征,从结构角度分析社会空间的参与者、基本组成和演化类型三个方面的内容。结果表明:(1)在参与农村社会空间演化的过程中,政府的主导作用最为显著,乡村精英起着承上启下的作用,外部工商资本是新的推动力量,本地农民是农村社会空间生成的基质;(2)山区农村社会空间由物理空间、意愿—行动空间和制度空间三个层次有机结合、共同构成;(3)山区农村社会空间的演化过程可以分成生产、分离、转移、扩展、压缩和消亡等几种基本演变类型。通过空间规划中考虑营造植根于农村并能扩展的社会空间,引导山区农村社会在变革中向良性发展,可为乡村振兴战略的具体实施提供指导。 相似文献
912.
泥石流起动的突变学特征 总被引:14,自引:1,他引:14
泥石流起动是泥石流发生、发展、成灾全过程中的关键环节,起动规律是泥石流预测预报和灾害防治的理论基础。对建立在实验基础上的泥石流起动条件进行适当变换,得到泥石流起动势函数,它符合尖点突变模型。进一步分析,发现准泥石流体起动时具有突变、缓慢和过渡状态等多条路径,并在起动临界点附近具有发散性和模态软化等性质。根据这些起动特性提出的单沟泥石流预测方法以及通过调控准泥石流体起动条件使之不起动,达到泥石流灾害治理防患于未然的新途径,已在泥石流防治中取得了实效。 相似文献
913.
甘肃省自然灾害及其防治对策 总被引:1,自引:1,他引:1
本文就甘肃省自然灾害的类型、分布、成因及其对社会经济的影响进行了分析研究,并提出了防治对策。 相似文献
914.
环境产品贸易为应对全球环境变化的国际合作提供了新途径。中国在可再生能源设备等方面具有优势,环境产品贸易有利于落实碳达峰与碳中和目标。分析中国1996—2019年环境产品进出口规模、产品结构与贸易网络结构的变化,应用LMDI方法将碳排放分解为排放强度、能源效率、经济水平和人口规模四个分量,借助ARDL-ECM模型验证环境产品贸易与碳排放的协整关系及长短期效应。结果表明:(1)中国环境产品贸易对碳排放的影响表现为短期促进作用和长期抑制作用。(2)环境产品贸易主要通过促进能源效率的碳减排效应、抑制经济增长的碳排放效应而推动碳减排。(3)贸易产品专业化短期有利于碳减排,但从长期看多元化更有利。贸易影响力提升短期对碳减排有利,但对进口的长期依赖不利于碳减排。(4)碳减排不只靠能源相关产品,非能源相关产品贸易同样能促进经济提质增效而推动碳减排。 相似文献
915.
基于AIS数据的中国沿海集装箱港口碳排放 总被引:1,自引:0,他引:1
为了精确有效地测量船舶在港碳排放,提出了一种基于海量船舶AIS (Automatic identification System)航行轨迹数据的港口碳排放计算框架,并结合上市港务公司经营数据,估算港口碳排放承担能力.以中国11个沿海主要集装箱港口为例,采用2018年全球4280艘集装箱船的AIS轨迹全年数据计算碳排放社会成本.结果显示:中国沿海集装箱港口碳排放量与船舶抵港艘次整体呈正相关,上海港是全球第一大集装箱港口,2018年其港口CO2排放量最高,为69.3万t;船舶靠港作业时,在泊和锚泊状态CO2的排放比例较高,占碳排放比例的65.8%;从CO2排放社会成本来看,上海港域内的船舶碳排放社会成本最高,2018年需要支付2459.6万元,从承担碳排放社会成本的能力来看,连云港压力较大,每亿营业收入需要承担碳排放社会成本24.46万元. 相似文献
916.
Cristina Quintas-Soriano Dainee M. Gibson Jodi S. Brandt María D. Lpez-Rodríguez Javier Cabello Pedro A. Aguilera Antonio J. Castro 《Ambio》2021,50(1):150
Conservation easements are the fastest growing private conservation strategy in the United States. However, mechanisms to assess private land conservation as well as their support by the general public are not well understood. This study uses the ecosystem services framework for assessing existing private lands in Idaho and identifies areas for future conservation easements. Using conservation targets of the land trust as a guide for selecting ecosystem services, we (a) mapped the spatial delivery of conservation targets across public and private lands, (b) explored public awareness in terms of social importance and vulnerability, and (c) mapped future priority areas by characterizing conservation bundles. We found that public lands provided the highest levels of conservation targets, and we found no difference in conservation target provision between private areas and conservation easements. The spatial characterization of conservation target bundles identified potential future priority areas for conservation easements, which can guide planning of land trust conservation efforts.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01323-x) contains supplementary material, which is available to authorized users. 相似文献
917.
Oliver C. Stringham Adam Toomes Aurelie M. Kanishka Lewis Mitchell Sarah Heinrich Joshua V. Ross Phillip Cassey 《Conservation biology》2021,35(4):1130-1139
The unrivaled growth in e-commerce of animals and plants presents an unprecedented opportunity to monitor wildlife trade to inform conservation, biosecurity, and law enforcement. Using the internet to quantify the scale of the wildlife trade (volume and frequency) is a relatively recent and rapidly developing approach that lacks an accessible framework for locating relevant websites and collecting data. We produced an accessible guide for internet-based wildlife trade surveillance. We detailed a repeatable method involving a systematic internet search, with search engines, to locate relevant websites and content. For data collection, we highlight web-scraping technology as an efficient way to collect data in an automated fashion at regularly timed intervals. Our guide is applicable to the multitude of trade-based contexts because researchers can tailor search keywords for specific taxa or derived products and locations of interest. We provide information for working with the diversity of websites used in wildlife trade. For example, to locate relevant content on social media (e.g., posts or groups), each social media platform should be examined individually via the site's internal search engine. A key advantage of using the internet to study wildlife trade is the relative ease of access to an increasing amount of trade-related data. However, not all wildlife trade occurs online and it may occur on unobservable sections of the internet. 相似文献
918.
919.
Vertebrate animals can be injured or threatened with injury through human activities, thus warranting their “rescue.” Details of wildlife rescue, rehabilitation, release, and associated research (our 4 Rs) are often recorded in large databases, resulting in a wealth of available information. This information has huge research potential and can contribute to understanding of animal biology, anthropogenic impacts on wildlife, and species conservation. However, such databases have been little used, few studies have evaluated factors influencing success of rehabilitation and/or release, recommended actions to conserve threatened species have rarely arisen, and direct benefits for species conservation are yet to be demonstrated. We therefore recommend that additional research be based on data from rescue, rehabilitation, and release of animals that is broader in scope than previous research and would have community support. 相似文献
920.
Linkages between measures of biodiversity and community resilience in Pacific Island agroforests
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Tamara Ticktin Shimona Quazi Rachel Dacks Mesulame Tora Ashley McGuigan Zoe Hastings Alivereti Naikatini 《Conservation biology》2018,32(5):1085-1095
Designing agroecosystems that are compatible with the conservation of biodiversity is a top conservation priority. However, the social variables that drive native biodiversity conservation in these systems are poorly understood. We devised a new approach to identify social–ecological linkages that affect conservation outcomes in agroecosystems and in social‐ecological systems more broadly. We focused on coastal agroforests in Fiji, which, like agroforests across other small Pacific Islands, are critical to food security, contain much of the country's remaining lowland forests, and have rapidly declining levels of native biodiversity. We tested the relationships among social variables and native tree species richness in agroforests with structural equation models. The models were built with data from ecological and social surveys in 100 agroforests and associated households. The agroforests hosted 95 native tree species of which almost one‐third were endemic. Fifty‐eight percent of farms had at least one species considered threatened at the national or international level. The best‐fit structural equation model (R2 = 47.8%) showed that social variables important for community resilience—local ecological knowledge, social network connectivity, and livelihood diversity—had direct and indirect positive effects on native tree species richness. Cash‐crop intensification, a driver of biodiversity loss elsewhere, did not negatively affect native tree richness within parcels. Joining efforts to build community resilience, specifically by increasing livelihood diversity, local ecological knowledge, and social network connectivity, may help conservation agencies conserve the rapidly declining biodiversity in the region. 相似文献