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131.
李佳慧  黄麟  曹巍 《地理学报》2022,77(5):1260-1274
生态资源资产化、生态资产资本化是实现“两山”转化的一个重要途径,开展生态资产及其损益核算有助于生态系统的有效保护、科学管理和可持续利用。本文在借鉴国内外生态资产相关研究的基础上,构建了县域尺度生态资产及其损益核算技术体系,分析了1990—2018年中国县域生态资产的时空变化特征,明晰了造成生态资产损益的影响因素及作用机制,并针对具有不同生态资源类型、损益状况、驱动要素特征的县域提出了差异化的优化提升路径。结果表明:① 以农田、森林生态资源为主的县域数分别约占县域总数的45%和37%;1990—2018年中国县域生态存量资产的质量整体呈波动中上升趋势,而生态流量资产的变化趋势差异显著,近70%县域水源涵养量减少。② 生态流量资产价值呈现损与益态势的县域数分别约占44%和37%,空间分布呈现与“胡焕庸线”一致的分割特征,即西北广大地区县域明显增益,而东部和南部县域有所减损。③ 1990—2018年中国超过70%县域生态资产变化受气候变化与人类活动共同驱动,人类活动对生态资产增益县域的平均作用率约80%,而气候变化对生态资产减损县域的平均作用率约为60%。④ 综合分析,可将全国县域分为适应、减缓气候变化和生态资源修复、保护、管理5种类型,采用差异化的生态资产优化提升路径。  相似文献   
132.
曹小曙 《地理科学》2022,42(1):31-42
人类关键区是人类社会进入人类世时代,人类所创造的地表景观在地理圈层中的特征区域。人类近万年历史对人地关系的认知可分为人类文明与地球环境、人类活动与地理环境、空间行为与土地利用3个层级。人类关键区具有全球尺度、国家尺度、区域尺度、地方尺度以及社区尺度。全球尺度的人类关键区可划分为建成区、农业区、生态区、裸露区。人类关键区未来的研究主要包括人类关键区的识别,人类关键区物质循环与能量流动,人类关键区耦合机理与动力机制,人类关键区地理模拟(器)与调控决策。人类关键区的提出为全球可持续发展提供中国地理科学的创新理论与实践路径。  相似文献   
133.
传统村落人居环境转型的系统特征、研究趋势与框架   总被引:1,自引:0,他引:1  
曾灿  刘沛林  李伯华 《地理科学进展》2022,41(10):1926-1939
传统村落作为中国乡村转型发展研究的重要载体之一,其人居环境是村落自然环境选址、空间功能表达、社会文化建构的综合体现,也是传统农耕文明的活态表现。论文通过界定传统村落概念、梳理传统村落人居环境内涵与系统构成、明晰传统村落人居环境转型特征与表现,从系统角度构建传统村落人居环境转型发展的研究范式。结果表明:① 传统村落人居环境转型发展研究可从转型内涵界定、转型系统构成与表现、转型阶段划分与空间分异、转型发展路径与模式等方面展开。② 传统村落人居环境包含主体、空间、功能3个维度,自然生态、社会文化、产业经济、地域空间、多元主体5大子系统,其各子系统转型互为依存又各有侧重,需分类施策。③ 自然生态、地域空间系统是传统村落人居环境转型传统研究范式,属于对“原生物质空间”的研究;社会文化、多元主体、产业经济系统为新近研究范式,属于对“建构性物质空间”的研究;基于问题、目标、需求导向,从系统角度综合研究转型发展则是未来人居环境研究的新趋势。  相似文献   
134.
程艺  刘慧  宋涛  张芳芳 《地理科学进展》2022,41(10):1940-1955
边境地区是重要的国家安全屏障和多重权力空间影响下的特殊脆弱地带。科学总结边境研究发展历程有助于厘清边境研究脉络,为实现边境长治久安与可持续发展提供科学支撑。论文以中国知网(CNKI)和科学引文索引(Web of Science)中人文地理学相关视域下的中国边境研究学术论文为依据,借助科学知识图谱方法,分析了1990年以来中国边境研究历程、趋势及热点等基本特征。研究发现:中国边境研究经历了“开放探索—社会建构—战略引领”的发展历程,研究热点区域逐渐由东北地区转向西南地区,“边境贸易”“边境旅游”“边境口岸”“一带一路”是4个核心关键词聚类。边境研究主要内容包括边境贸易与开发开放、边境旅游资源开发、社会建构与和谐发展、边境口岸与城市功能,以及地缘环境与边境安全。当前,中国边境研究在规律探索、定量总结等方面仍然不足,论文在构建多要素—多主体—多尺度集成的边境地理研究框架基础上,提出未来应加强边境风险与安全、跨境合作机制、边境效应理论、边境可持续发展等研究,为后续边境研究提供参考,支撑中国边境安全与现代化治理。  相似文献   
135.
在贵州冬季相对湿度大、风速小的气候背景下,综合考虑气温和相对湿度对人体舒适度的影响,计算并讨论了9个市州代表站人体舒适度指数IHC及其对温湿环境的响应,发现贵州省冬季低温、高湿对IHC指数具有负贡献,其中气温的高低对IHC指数影响尤为明显,并且在平均相对湿度越高的环境下,IHC指数对平均气温的变化就具有越高的敏感性,因此在贵州省西部和北部地区冬季由于平均气温较低、加之平均相对湿度较大,人体舒适感降低尤为明显。从回归方程出发,讨论贵州省冬季△IHC对△T=1σ或△RH=1σ变化的响应,发现平均气温是影响IHC指数变化的主要指标,而相对湿度作为辅助指标对IHC指数有着增大或减小的调节作用。通过分析IHC指数的稳定持续性,发现其能有效客观的表征出贵州省低温的持续性特征,并且能反映出在平均相对湿度较高的环境下,人体感觉的不舒适持续日数增加,即加大了人体的不舒适感。  相似文献   
136.
Identifying and characterizing variations of human activity – specifically changes in intensity and similarity – in urban environments provide insights into the social component of those eminently complex systems. Using large volumes of user-generated mobile phone data, we derive mobile communication profiles that we use as a proxy for the collective human activity. In this article, geocomputational methods and geovisual analytics such as self-organizing maps (SOM) are used to explore the variations of these profiles, and its implications for collective human activity. We evaluate the merits of SOM as a cross-dimensional clustering technique and derived temporal trajectories of variations within the mobile communication profiles. The trajectories’ characteristics such as length are discussed, suggesting spatial variations in intensity and similarity in collective human activity. Trajectories are linked back to the geographic space to map the spatial and temporal variation of trajectory characteristics. Different trajectory lengths suggest that mobile phone activity is correlated with the spatial configuration of the city, and so at different times of the day. Our approach contributes to the understanding of the space-time social dynamics within urban environments.  相似文献   
137.
为了解决土地利用的种类复杂、分界不清、分界点精度要求高等问题,研制集GPS,Mobile GIS,PDA,网络通信等先进技术为一体的,能够快速获取土地利用信息的土地集约利用信息采集终端系统,为城市土地集约化利用信息及时、准确的获取提供技术保障。  相似文献   
138.
Dating data, altitude of Neolithic sites, climatic changes from sedimentary records and previous research results were collected and analyzed to detect possible connections between climatic changes and human activities in the Changjiang River Delta in the Neolithic Age. The results indicated that hydrological changes greatly impacted the human activities in the study region. Low-lying geomorphology made the floods and sea level changes become the important factors affecting human activities, especially the altitude change of human settlements. People usually moved to higher places during the periods characterized by high sea level and frequent floods to escape the negative influences from water body expansion, which resulted in cultural hiatus in certain profiles. However, some higher-altitude settlements were not the results of climatic changes but the results of social factors, such as religious ceremony and social status. Therefore, further research will be necessary for the degree and types of impacts of climatic changes on human activities in the study area at that time.  相似文献   
139.
Much attention has recently been focused on the effects that climate variability and human activities have had on runoff. In this study, these effects are quantified using three methods, namely, multi‐regression, hydrologic sensitivity analysis, and hydrologic model simulation. A conceptual framework is defined to separate the effects. As an example, the change in annual runoff from the semiarid Laohahe basin (18 112 km2) in northern China was investigated. Non‐parametric Mann‐Kendall test, Pettitt test, and precipitation‐runoff double cumulative curve method were adopted to identify the trends and change‐points in the annual runoff from 1964 to 2008 by first dividing the long‐term runoff series into a natural period (1964–1979) and a human‐induced period (1980–2008). Then the three quantifying methods were calibrated and calculated, and they provided consistent estimates of the percentage change in mean annual runoff for the human‐induced period. In 1980–2008, human activities were the main factors that reduced runoff with contributions of 89–93%, while the reduction percentages due to changes in precipitation and potential evapotranspiration only ranged from 7 to 11%. For the various effects at different durations, human activities were the main reasons runoff decreased during the two drier periods of 1980–1989 and 2000–2008. Increased runoff during the wetter period of 1990–1999 is mainly attributed to climate variability. This study quantitatively separates the effects of climate variability and human activities on runoff, which can serve as a reference for regional water resources assessment and management. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
140.
The reef islands formed on coral atolls are generally small, low, and flat, with elevations of only a few meters. These islands are thus highly vulnerable to elevated sea levels caused by extreme events and global warming. Such vulnerability was recently evidenced at Fongafale Islet, the capital of Tuvalu, when it flooded during accelerated spring high tides possibly related to sea level rise caused by global warming. Many factors, not only environmental but also economic and social, determine the vulnerability of an island to sea level rise. In this study, we used data spanning 108 yrs to reconstruct changes in topography, land use/cover, population, and the distribution of buildings at Fongafale Islet. The results indicate that the vulnerability of Fongafale Islet relates to its original landform characteristics: the central part of the island was formerly dominated by swampland that flooded at high tides. Fongafale Islet experienced greater population in-migration and centralization beginning in the 1970s following the independence of Tuvalu and Kiribati. Migrants were also responding to declines in overseas mining operations and limited options for paid employment. As the population increased, construction took place in vulnerable swampland areas. Our results clearly demonstrate that examinations of global environmental issues should focus on characteristics specific to the region of interest. These characteristics should be specified using historical reconstruction to understand and address the vulnerability of an area to global environmental changes.  相似文献   
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