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1.
受气候变化和政策因素的影响,哈萨克斯坦是中亚地区生态退化和草畜矛盾最为突出的国家。研究哈萨克斯坦草地承载状态对认识草地生态系统对气候变化和人类活动的响应尤为重要。本研究基于哈萨克斯坦遥感数据和畜牧业统计数据,以生态系统的供给与消耗为基础,分析哈萨克斯坦草地生态系统与承载状态的格局变化。结果表明:(1)2003–2017年,哈萨克斯坦牲畜养殖数量呈现持续平稳增长的趋势,受冻害影响,在2011年数量有所减少,牲畜养殖结构空间差异不明显。(2)哈萨克斯坦草地供给量波动上升,而畜牧业生产消耗量持续增加,导致草地承载压力不断增加。(3)2003–2017年间,哈萨克斯坦整体的草地承载状态一直呈现富余状态,但草地承载压力指数呈现平稳上升趋势,草地承载压力较大的地区主要位于草地生产力低下的克孜勒奥达尔州、耕地集中的南哈萨克斯坦州和北哈萨克斯坦州,并逐渐向农牧交错区和半荒漠带推进。  相似文献   

2.
水资源短缺是制约北京市经济社会可持续发展的关键因素。本研究基于水量平衡方程从市域、主体功能区、重点区县的多个尺度分析北京市水源涵养服务的时空格局,明确北京市不同土地覆被类型的水源涵养量差异,探究水源涵养量时空格局差异的原因。结果表明:(1)与2005年相比,2010年北京市水源涵养量明显增加,但是总体上水源涵养能力较低;(2)北京市各土地覆被类型中,湿地、林地、草地、耕地、裸地、人工表面的平均水源涵养能力依次降低;(3)北京市各主体功能区的平均水源涵养量差异较大,只有生态涵养发展区的平均水源涵养量为正值;(4)北京市生态涵养发展区内各区县的水源涵养功能也存在明显差异,密云区、怀柔区、平谷区的森林水源涵养贡献率最高。北京市水源涵养的时空格局变化是地表覆被和气象条件变化综合影响的结果。本研究对于实现北京市水资源的可持续利用具有重要的借鉴意义。  相似文献   

3.
新冠肺炎疫情爆发后,全球旅游业面临着巨大挑战,亟需探索一条有效的恢复振兴路径。随着疫情发生的常态化趋势,旅游目的地会愈发关注对疫情的防范预警和应对策略,疫情后期旅游目的地的恢复力研究也必将得到重视。目前学术界已有部分关于旅游疫情危机和旅游恢复力的研究,但是较少将其综合起来研究疫情后期旅游目的地恢复力,尚未有研究提出系统的研究思路和方法。文章以恢复力理论为基础,梳理了总体研究思路,构建了适合城市旅游目的地的疫情危机恢复力模型。在此基础上,提出了一套基于指标体系的疫情后期旅游目的地恢复力及其时空动态分析的研究方法,并从研究内容、数据来源、研究方法三个方面具体阐述了研究体系,即:首先从理论上构建疫情后期旅游目的地恢复力的概念模型和评价体系;其次选择案例地进行实证分析,测算旅游目的地的恢复力,分析时空差异特征及影响因素;最后构建旅游目的地应对疫情危机的适应性管理机制,指导旅游业疫后恢复政策的制定。  相似文献   

4.
自然资源要素综合观测平台的建设,将为研究各种自然资源的动态变化提供数据支持,有效服务于全球变化下自然资源管理和生态文明建设。黑河流域作为西北地区第二大内陆河流域,处于丝绸之路经济带的核心地段,迫切需要在黑河流域开展试点研究。本文依托黑河流域现有观测研究基础,采用融合共建、改建升级和空白添建三种方式,分流域、分级别布设观测台站13个,基本覆盖了黑河流域草原、森林、河流、湖泊、荒漠、湿地、农田等主要地表资源类型,初步构建起黑河流域自然资源要素综合观测网络。通过长期、连续、稳定的观测,获取资源间耦合作用过程、变化趋势和速度等关键数据,对提高黑河流域自然资源认知能力、科学管理和战略决策具有十分重要的意义,对其它流域开展自然资源观测研究也具有重要的借鉴和示范意义。  相似文献   

5.
6.
Sustainable development has always been a hotspot in Chinese geographical research. Herein, we conduct a systematic statistical analysis of the contribution of Chinese geographers to sustainable development research using bibliometric methods. Based on the review of a vast amount of literature, we identify the main research teams, research funding sources, journals, and key research fields. The findings are as follows:(1) the resources and environmental institutes of the Chinese Academy of Sciences have a significant influence on sustainable development research;(2) China's central government foundations(the National Natural Science Foundation of China and National Social Sciences Fund) are the main research funding sources;(3) most of the highly cited articles are published in journals sponsored by the Geographical Society of China; and(4) sustainable development theory and its research areas are being constantly enriched and perfected. Based on the statistics of keywords, the theory, research methods, research regional scales, and key research areas are summarized and expounded.  相似文献   

7.
中国生态交错带(英文)   总被引:2,自引:0,他引:2  
生态交错带(Ecotone)是指两个群落或两类生态系统之间的过度带,具有脆弱、敏感和易变等特性。20世纪70年代以来,在典型生态系统研究的基础上,生态交错带逐步成为生态学研究的重点。中国地域广阔,地质、气候、植被等生态类型复杂多变,蕴育了不同类型、不同尺度和不同规模的多种生态交错带,不仅为科学研究奠定了广阔空间,而且对我国经济、社会发展,以及文化多样性保护具有重要支撑作用。本文根据我国大尺度下生态交错带的地理分布及其生态环境特点,构建了以土地利用类型、自然气候特征和农业经济发展"三位一体"指标体系,并以此为依据对中国典型生态交错带进行了划分和空间分布范围的界定;在此基础上,分别对北方森林草原交错带、北方农牧交错带、西北荒漠绿洲交错带、西南川滇农林牧交错带和东部海陆交错带的动态变化、基本特征和存在问题进行了研究,对全面认识我国生态交错带自然演变规律,促进区域生态环境保护和优化经济发展具有重要意义。  相似文献   

8.
In Southwest China, five Nature Reserves(NRs)(Mangkang, Baimaxueshan, Yunling, Habaxueshan, and Yunlongtianchi) play a key role in protecting the endemic and endangered Yunnan snub-nosed monkey(YSM)(Rhinopithecus bieti). However, increasing human activities threaten its habitats and corridors. We used a GIS-based Niche Model to delineate potential core habitats(PCHs) of the YSMs and a Linkage Mapper corridor simulation tool to restore potential connectivity corridors(PCCs), and defined five scenarios. A normalized importance value index(NIVI) was established to identify the protection priority areas(PPAs) for the YSMs for five scenarios. The results indicated that locations of the habitats and corridors were different in the five scenarios, thereby influencing the distribution of the PPAs and protection network of the YSMs. The NIVI value of Baimaxueshan nature reserve was 1 in the five scenarios, which implied the maximum importance. There were only 7 PCHs and 16 PCCs(with the longest average length of 223.13 km) which were mainly located around 5 NRs in scenario III. The protection network of the YSMs was composed of 16 PCHs, 18 PCCs, and 5 NRs. Under each scenario, most of the PCHs and the PCCs were located in the south of the study area. The five NRs only covered 2 PPAs of the YSMs. We suggest that the southern part of the study area needs to be strictly protected and human activities should be limited. The area of the five NRs should be expanded to maximize protection of the YSMs in the future.  相似文献   

9.
The expansion and upgrading of Chinese industries have accompanied with the spatial restructuring process across the country. This paper provides a literature review on China's industrial geography, paying special attention to industrial agglomeration and industrial clusters. The increasing industrial agglomeration and development of industrial clusters have been the prominent characteristics of dynamics of industrial landscape in China. The major driving forces of China's industrial geography include economic globalization, decentralization and regional competition and rebuilding of regional advantages. This paper concludes with a discussion of future research focus.  相似文献   

10.
Geomorphometry,the science of digital terrain analysis(DTA),is an important focus of research in both geomorphology and geographical information science(GIS).Given that 70% of China is mountainous,geomorphological research is popular among Chinese scholars,and the development of GIS over the last 30 years has led to significant advances in geomorphometric research.In this paper,we review Chinese progress in geomorphometry based on the published literature.There are three major areas of progress:digital terrain modelling methods,DTA methods,and applications of digital terrain models(DTMs).First,traditional vector-and raster-based terrain modelling methods,including the assessment of uncertainty,have received widespread attention.New terrain modelling methods such as unified raster and vector,high-fidelity,and real-time dynamic geographical scene modelling have also attracted research attention and are now a major focus of digital terrain modelling research.Second,in addition to the popular DTA methods based on topographical derivatives,geomorphological features,and hydrological factors extracted from DTMs,DTA methods have been extended to include analyses of the structure of underlying strata,ocean surface features and even socioeconomic spatial structures.Third,DTMs have been applied to fields including global climate change,analysis of various typical regions,lunar surface and other related fields.Clearly,Chinese scholars have made significant progress in geomorphometry.Chinese scholars have had the greatest international impact in areas including high-fidelity digital terrain modelling and DTM-based regional geomorphological analysis,particularly in the Loess Plateau and the Tibetan Plateau regions.  相似文献   

11.
农牧结合是高寒牧区放牧系统的一项重要的实践,具有实现农业和牲畜业可持续生产的重大潜力。然而,目前青藏高原的农牧业分离已经导致集约化农业、草地退化和饲料短缺的问题产生。因此,为探索高山放牧系统中农牧结合的潜力,本研究以中国普兰县为例,基于多数据源,分析了牧草生产潜力和牲畜产量,并从饲草供给角度评估了农牧结合的潜力。结果表明:普兰县可用于人工种草的潜在边际土地约560公顷,基本位于环境条件较好的普兰镇周边。而积温是牧草种植的主要环境限制因子,今后牧草种植应注重品种的抗寒性和生长周期,同时也要注意人工草地建立后的退化和沙化问题。另外,虽然2012–2016年普兰县牲畜数量明显下降,但高寒草地放牧牲畜数量依然高于农牧景观的牲畜放牧数量。该地区目前放牧牲畜数量一般维持在约11万只羊单位,而人工草地和作物秸秆能够提供约1.1万只羊单位的饲料,约占农牧景观中牲畜数量的一半。普兰县农牧结合可以适当补充放牧条件下牲畜饲料的缺额,尤其是在农牧区的普兰镇。本研究结果对未来牧草生产和发展农牧结合具有重要的指导意义。  相似文献   

12.
Geographical circumstances are the fundamental background for all kinds of geopolitical events. The geopolitical environment system(GES) refers to a system that combines both physical and anthropogenic subsystems. Research on the geopolitical environment system simulation is a key to understanding the international geopolitical phenomenon. The theory of GES arose from the integration of the traditional geopolitics and earth system sciences. As an interdisciplinary system composed of many different fields, integrated reviews and a metadata study of GES are urgently needed. This paper presents a comprehensive view into the origination and advance of the GES theory. The conceptual framework of the GES is described in detail. The methodology for simulating and forecasting geopolitical events is also provided. It is proposed that the core topics of the GES science may include, but are not limited to, issues as data acquisition technologies; principles on the interactions between multiple subsystems(or factors) at different scales; evaluating and mitigating the global geopolitical risks, including the political risks, economic risks, the social risks, the environmental risks and the technological risks; and forecasting the geopolitical events with machine learning and artificial intelligence techniques.  相似文献   

13.
As an important branch of human geography, transportation geography has experienced three periods of evolution: foundation, systematization, and rapid development of the discipline. It has gradually become a relatively mature discipline. During the period 1930– 1980, the development of transportation geography consisted mainly of the publication of theoretical texts. During 1980–2000, it gradually became a systematic discipline. Since the start of the 21 st century, transportation geography has focused mainly on exploring the impacts of transportation on socio-economic development. Currently, studies on transportation geography have led to significant developments in a number of areas, including transportation theory, facility distribution and planning, transportation flows and network analysis, evaluation of transport modes, transportation planning, and simulation and assessment of urban transportation. Such studies have also enriched human geography research, provided a wider geographical overview and elucidated the development mechanism of transportation, as well as helped to understand the impacts of transport development on socio-economic systems. Some findings obtained by geographers have been widely used in transportation geography and related fields, including the four basic laws of transportation generation, the hub–spoke mode of transport organization, the subordinating and guiding functions of transportation on socio-economic development, regional transport dominance measures, accessibility measures, and spatial organization of port systems.  相似文献   

14.
Land surface is of spatial-temporal heterogeneity. Terrestrial system(TS) comprehensively studies on land surface and physical regionalization objectively describes geographical zonation of the system. China has a vast area with apparent spatial variations in resources and environmental conditions, which highly influence on socio-economic development. In this paper, progress of the TS studies in China is overviewed and research priorities in the near future are prospected. Since the 1950 s, China has paid great attention to the TS study as its socio-economic development, and conducted research on physical geographical regionalization, eco-geographical regionalization and comprehensive regionalization. Along with the deepening of global change research, dynamics of TS have been highly concerned. During the studies, methodology has been developed from qualitative research of integration of experts' brainpower gradually to quantitative research based on field observation and experiments of the natural processes, including physical, chemical and biological processes, as well as application of information technology and mathematical simulation. In the near future, TS would combine with the ideology, objectives and key researches of Future Earth program, to focus on the mechanism and regional effects of interaction among land surface elements, the response of TS to global change, the quantitative recognition on regional unit boundary, and the application to TS in sustainable socio-economic development.  相似文献   

15.
Economic geography in China's mainland has developed in a different way from that in many other countries. On the one hand, it has been increasingly active in participating in academic dialogues and knowledge development led by Anglophone countries; on the other hand, it takes practice-based and policy-oriented research, i.e. satisfying the demands from the Chinese government and society, as the linchpin of research. Since there has been a lot of literature reviewing the development of economic geography in the country before the new millennium, this paper will make a comprehensive analysis of the discipline in 2000–2015, based on a bibliometric survey and research projects done by Chinese economic geographers. The analysis indicates that(1) economic geography research in China's mainland is unevenly distributed but concentrated in several leading institutions;(2) traditional research fields like human-nature system, regional disparity, industrial location and transportation geography remain dominant while new topics such as globalization, multinational corporations and foreign direct investments, information and communication technology, producer services, climate change and carbon emission emerge as important research areas;(3) Chinese economic geography is featured by policy-oriented research funded by government agencies, having considerable impacts on regional policy making in China, both national and regional. To conclude, the paper argues that the development of economic geography in China's mainland needs to follow a dual track in the future, i.e. producing knowledge for the international academic community and undertaking policy-oriented research to enhance its role as a major consulting body for national, regional and local development.  相似文献   

16.
Evolution of river systems under the background of human activities has been a heated topic among geographers and hydrologists. Spatial and temporal variations of river systems during the 1960s–2010s in the Yangtze River Delta(YRD) were investigated based on streams derived from the topographic maps in the 1960 s, 1980 s and 2010 s. A list of indices, drainage density(Dd), water surface ratio(WSR), ratio of area to length of main streams(R), evolution coefficient of tributaries(K) and box dimension(D), were classified into three types(quantitative, structural, and complex indices) and used to quantify the variations of stream structure. Results showed that:(1) quantitative indices(Dd, WSR) presented decreasing trend in the past 50 years, and Dd in Wuchengxiyu, Hangjiahu and Yindongnan have decreased most, about 20%. Structurally, the Qinhuai River basin was characterized by significant upward R, and K value in Hangjiahu went down dramatically by 46.8% during the 1960s–2010s. Decreasing tendency in D was found dominating across the YRD, and decreasing magnitude in Wuchengxiyu and Hangjiahu peaks for 7.8% and 6.5%, respectively in the YRD.(2) Urbanization affected the spatial pattern of river system, and areas with high level of urbanization exhibited least Dd(2.18 km/km2), WSR(6.52%), K(2.64) and D(1.42), compared to moderate and low levels of urbanization.(3) Urbanization also affected the evolution of stream system. In the past 50 years, areas with high level of urbanization showed compelling decreasing tendency in quantitative(27.2% and 19.3%) and complex indices(4.9%) and trend of enlarging of main rivers(4.5% and 7.9% in periods of the 1960s–1980s and the 1980s–2010s). In the recent 30 years, areas with low level of urbanization were detected with significant downward trend in Dd and K.(4) Expanding of urban land, construction of hydraulic engineering and irrigation and water conservancy activities were the main means which degraded the river system in the YRD.  相似文献   

17.
本文在界定生态技术概念和生态技术识别需求的基础上,梳理了现有的技术识别的方法。目前应用于技术辨识的方法主要有德尔菲法、技术路线图、层次分析法、专利计量法和文本挖掘法。其中"德尔菲法+层次分析法"把生态技术纳入到社会经济系统中进行系统化的识别,主要是构建生态技术识别的指标体系模型,分别从技术特性、技术水平和性能、经济、社会和生态效益视角进行识别;专利计量法从客观角度出发,依据生态技术自身的特点和发展规律,对其进行识别。本文认为"德尔菲法+层次分析法"和专利计量法这两种方法结合了定性和定量技术识别的优点,应该成为开展生态技术识别的首选。  相似文献   

18.
生态系统为人类提供了必要的服务,其中大部分是没有市场价格的,因此被认为是"自然的免费赠品"而被大量使用。近年来由于快速的工业化和城市化,不断增长的人口已经使人们认识到生态系统服务也是有限的。环境退化是用来描述生态系统服务的损失或损害的常用指标,而移民往往是环境恶化的后果。那么,生态系统服务退化到什么程度才足以导致人们搬迁?本文通过对移民和环境退化相关文献的综述,力求寻求及时监测生态系统退化状况、避免人类承受生态移民痛苦、探求不同环境下人类更好地生存与发展的途径。  相似文献   

19.
Unimpeded trade is one of the cooperation priorities in the Belt and Road Initiative proposed by China. On 15 May 2017, the Joint Communique of the Leaders Roundtable of the Belt and Road Forum for International Cooperation reaffirmed the participants' shared commitment to build an open economy and ensure free and inclusive trade. The Belt and Road Initiative(BRI) is not only China's new action to drive its open and global development, but also a platform for an increasing number of countries to explore free and inclusive trade and promote a universal, rule-based, open, non-discriminatory, and equitable multilateral trade system. It is therefore important to examine the topological relationship between the BRI and global trade networks. More specifically, this article first analyzes the community structure of trade networks using a community detection algorithm, and then estimates the topological relationship between different trade communities. The findings of this article are as follows. First, this research identified three trade communities and two sub-communities in the BRI trade network, in which China is the core, Russia is the sub-core of the biggest trade community, and India, United Arab Emirates, and Saudi Arabia are cores of the second trade community(South Asia-West Asia). Second, it identified five trade communities in the global trade network, centred on China, USA, Russia, India-United Arab Emirates, and Germany-Netherlands-France-Britain and other European developed countries. Third, the topological analysis indicated that in the global trade network, most BRI countries are attracted by the core nodes of the BRI regions, such as the China, Russia and India-United Arab Emirates core nodes, and have strong trade contacts with BRI countries. Most Central-East European countries are mainly attracted by Germany-Netherlands-France-Britain and other developed European countries with a low penetration of BRI trade. Although some Southeast Asian countries are incorporated into the Asia-Australia-South Africa community with China as the core, they still need to strengthen trade linkages with BRI countries.  相似文献   

20.
With the implementation of the "Going out" strategy and the Belt and Road Initiative, China's investments have become increasingly influential in the global market. The contemporary literature has revealed how overseas Chinese networks and communities have actively promoted foreign investments into China over the past four decades. Whether this factor can help Chinese capital flow out once again is still ambiguous. This study examines this question by investigating Chinese corporate investments in Southeast Asia from 2001 to 2016. Through the discrete-selection logistic regression model, the study analyzes the correlation between overseas Chinese social networks and the location choices of Chinese corporate investments. The results show the following:(1) overall, there is a significant positive correlation between the population of overseas Chinese in Southeast Asian countries and the location choices of Chinese corporate investments;(2) in terms of the time sequence, the significance of the correlation is increasing, which implies that overseas Chinese have positive impacts on promoting the location choice of Chinese enterprises and that the impact is potentially increasing; and(3) in terms of the industrial structure and corporate functions, the impacts vary and are only significant in some industries and corporate segments.  相似文献   

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