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1.
In areas with topographic heterogeneity, land use change is spatially variable and influenced by climate, soil properties, and topography. To better understand this variability in the high-sediment region of the Loess Plateau in which soil loss is most severe and sediment diameter is larger than in other regions of the plateau, this study builds some indicators to identify the characteristics of land use change and then analyze the spatial variability as it is affected by climate, soil property, and topography. We build two indicators, a land use change intensity index and a vegetation change index, to characterize the intensity of land use change, and the degree of vegetation restoration, respectively. Based on a subsection mean method, the two indicators are then used to assess the spatial variability of land use change affected by climatic, edaphic, and topographic elements. The results indicate that: 1) Land use changed significantly in the period 1998-2010. The total area experiencing land use change was 42,302 km2, accounting for 22.57%of the study area. High-coverage grassland, other woodland, and forest increased significantly, while low-coverage grassland and farmland decreased in 2010 compared with 1998.2) Land use change occurred primarily west of the Yellow River, between 35 and 38 degrees north latitude. The four transformation types, including (a) low-coverage grassland to medium-coverage grassland, (b) medium-coverage grassland to high-coverage grassland, (c) farmland to other woodland, and (d) farmland to medium-coverage grassland, were the primary types of land use change, together constituting 60% of the area experiencing land use change. 3) The spatial variability of land use change was significantly affected by properties of dryness/wetness, soil conditions and slope gradient. In general, land use changed dramatically in semi-arid regions, remained relatively stable in arid regions, changed significantly in clay-rich soil, remained relatively stable in clay-poor soil, changed dramatically in steeper slopes, and remained relatively stable in tablelands and low-lying regions. The increase in vegetation coincided with increasing changes in land use for each physical element. These findings allow for an evaluation of the effect of the Grain to Green Program, and are applicable to the design of soil and water conservation projects on the Loess Plateau of China.  相似文献   

2.
The excessive expansion of urbanized areas has resulted in haphazard land utilization, immoderate consumption of superior agricultural land and water resources, significant fragmentation of agricultural landscape, and gradual deterioration of the agro-ecological environment. Combined, these factors cause poor land use efficiency. Under these circumstances, comprehensively assessing land use efficiency for urban agriculture is a key issue in land use research. Currently, evaluation methods for agricultural land use efficiency narrowly concentrate on aspects of economic input and output. However, urban agro-ecosystems can provide diverse economic, social, and ecological services and functions. In particular, the social and ecological services and functions originating from agricultural land, which have a higher value than economic services, play a significant role in ensuring regional social, ecological, and environmental security. However, recent research has rarely taken these benefits into consideration. Therefore, land use value has been greatly underestimated, which has resulted in mishandled and poor land use policies. In this study, we apply Landsat imagery and social and economic statistical data for the Xi’an metropolitan zone (XMZ) to investigate agricultural multi-functionality. We develop an evaluation framework for urban agricultural land use efficiency and identify agro-ecosystem services and functions as important outputs from agricultural land. The land use efficiency of urban agriculture is then evaluated using ecosystem services models, providing a mechanism for assessing spatial-temporal changes in land use efficiency in the XMZ from 1999 to 2015. Four important conclusions are reached from this analysis. First, the rapid urbanization and agricultural transformation from traditional cereal cultivation to modern urban agriculture has resulted in steadily increasing costs, outputs, and land use efficiency of urban agriculture. The total output value increased 41% and land use efficiency per hectare increased by 33.13% on average. Second, the spatial patterns of comprehensive output and land use efficiency were dominated by economic outputs from agricultural land. Areas near cities, which are dominated by orchard and arable land, provide more economic functions. These areas support and regulate services due to the transformation from extensive cereal production to intensive modern urban agriculture; therefore, they have higher output value and land use efficiency. In contrast, areas distant from cities, towns, and high traffic roads, namely, remote rural areas, provide more support and regulating services, but have relatively lower economic function due to inaccessibility to urban markets and slow agricultural transformation. Therefore, these areas have lower output value and land use efficiency. The spatial change in agricultural output and land use efficiency in urban areas is strongly dependent on the degree of urbanization and agricultural transformation. Third, the total output value and land use efficiency of urban agriculture measured with our approach are much higher than evaluations using traditional methods. However, the spatial patterns measured using the two approaches are in agreement. The evaluation framework integrates ecological services and economic and social functions into a comprehensive output from agricultural land. This approach is more methodical and accurate for evaluating the comprehensive efficiency of land use based on quantities and spatial scale because they are at the pixel scale. Finally, the evaluation results have important implications for enhancing current agricultural subsidies and even implementing ecological payment policies in China. Most importantly, they can be directly applied to agricultural transformation regulations, decision- making, and guidance for rational land utilization.  相似文献   

3.
China's policy on ecological compensation (eco-compensation) in watershed eco-systems is of economic,social and environmental significance for China's ecological gov-ernance and protection of natural areas.It involves balancing the interests of regional stakeholders,coordinating the development of regional environments and establishing effec-tive cooperation models,making it a classic topic for geographical research.This study in-troduces the concept of institutional "stickiness" to the theory of politics of scale to analyze the features and mechanisms of the game behavior of government entities in the process of im-plementing watershed eco-compensation in the Xin'an River Basin.Our results show the following:government entities at various levels,including the central,provincial and municipal governments,experienced the three stages of game strategy of competition,cooperation and"coopetition";building a government community of shared interests can promote watershed eco-compensation,and "appropriate intervention" by the central govemment is key to achieving inter-provincial watershed eco-compensation;there was clear institutional stickiness during the transition from a "vertical" model of watershed eco-compensation to a "vertical-horizontal"model,with government entities using policy innovations and social participation to limit and reduce stickiness so as to reshape the watershed eco-compensation system;scalar jumping is the core mechanism that promoted eco-compensation in the study basin,and government entities shaped the discourse on watershed eco-compensation by redistributing powers and capital and creating informal constraints,which promoted the transformation of eco-compensation from a "strong state-weak society" structural model,to a "strong state-strong society" model in the Xin'an River Basin.These results can provide theoretical support for the construction of inter-regional watershed eco-compensation mechanisms,pro-vide a scientific basis for the rational evaluation and guidance of watershed eco-compensation practices,and promote the coordinated and sustainable socioeconomic development of watersheds.  相似文献   

4.
As the world’s largest developing country, the ability of China’s agricultural resource utilization to effectively support the current and future food security goals has been affected by a variety of factors (e.g., transformed supply channels, tightening international situation and frequent emergencies) in recent years and has attracted extensive attention from the academic community subject to multiple factors. This study uses literature review, statistical analysis, and spatial analysis methods to systematically explore China’s food security situation in the context of farmland resource constraints. It is found that the demand-side pressures such as demographic changes, social class differentiation, and dietary structure adjustments derived from economic growth and rapid urbanization have placed extremely high expectations on food supply. However, the quantitative restrictions, utilization ways, and health risks of farmland resources on the supply side constitute a huge hidden concern that affects the stability of food production. Although China’s farmland protection system is undergoing a transition from focusing on quantity management to sustainable use, the matching and coordinating demand pressure and supply capacity for food security is unbalanced. Therefore, facing uncertain future development scenarios, policymakers should focus on building a resilient space for China’s farmland protection to withstand the interference of major emergencies. The existing farmland protection space policy can be integrated by establishing a national farmland strategic reserve system (based on resilient space), and further development of targeted use control measures for zoning, grading, and classification will help realize sustainable China’s farmland resources use.  相似文献   

5.
Scientifically assessing the economic impact of major public health emergencies,containing their negative effects,and enhancing the resilience of an economy are important national strategic needs.The new coronavirus disease (COVID-19) has,to date,been effectively contained in China,but the threat of imported cases and local risks still exist.The systematic identification of the virus's path of influence and intensity is significant for economic recovery.This study is based on a refined multi-regional general equilibrium analysis model,which measures the economic and industrial impacts at different epidemic risk levels in China and simulates development trends and the degree of damage to industries and the economy under changes to supplies of production materials and product demand.The results show that,at the macroeconomic level,China's GDP will decline about 0.4% to 0.8% compared to normal in 2020,with an average drop of about 2% in short-term consumption,an average drop in employment of about 0.7%,and an average increase in prices of about 0.9%.At the industry level,the epidemic will have the greatest short-term impact on consumer and laborintensive industries.For example,the output value of the service industry will fall 6.3% compared to normal.Looking at the impact of the epidemic on the industrial system,the province most affected by the epidemic is Hubei,which is the only province in China in the level-1 risk category.As the disease spread outward from Hubei,there were clear differences in the main industries that were impacted in different regions.In addition,simulation results of recovery intensity of regional economies under the two epidemic response scenarios of resumption of work and production and active fiscal stimulus policies show that an increase in fiscal stimulus policies produces a 0.3% higher rate of gross regional product growth but it causes commodity prices to rise by about 1.8%.Measures to resume work and production offer a wider scope for industrial recovery.  相似文献   

6.
The world is currently undergoing profound changes, with a shift in global power centers and reordering of international power spaces, assigning new theoretical tasks as well as providing new opportunities for geopolitics research in China. Despite the peripheral nature of geopolitics research within their discipline, geographers have played a fundamental role in its origins and revival, from classical geopolitics (i.e., the German school of geopolitics and the Anglo-American school of geo-strategy), to internal geopolitics (i.e., electoral geography and administrative geography), to the new geopolitics (i.e., formal geopolitics), and to recent critical geopolitics (i.e., popular geopolitics). Although only few of these researchers were from China, great strides have been made in geopolitics and political geography research in China, with useful results being obtained. After demonstrating the importance of geopolitics research for the rising China, this review provides an overview of geopolitics papers led by China’s geographers in the past few decades, describing their achievements, the problems they have faced, and the directions they have taken. Twenty-five years of geopolitics have produced a range of accomplishments, with a growth in the quality and size of research groups and institutions, an expanding literature, and some geo-strategic break-throughs. Obviously, geographers have successfully reclaimed geopolitics, but some crucial topics are still absent or weak in the geopolitical research agenda, and need to be pursued vigorously. Most of the attention, from a positivistic perspective, has been paid to reflecting Western geopolitical thoughts, describing patterns of international power relations, and offering foreign policy advice (in a problem-focused orientation), rather than determining mechanisms and performing theoretical analyses (in a theoretical orientation), resulting in a lack of independent value judgments and of a theoretical basis for the subject. Moreover, in comparison with other disciplines, in terms of its academic community, research output, and status as a discipline, geopolitics research is very different from how it was three or four decades ago, when it was mainly the property of geographers, rather than political scientists and diplomats. For now, whether to support national geo-strategies or to enhance the diversity of the discipline, the involvement of geographers in geopolitics needs to become both more intensive and more extensive. The top priority is to strengthen theoretical, methodological, and problem- oriented research, including studies of geopolitical philosophy and methodology, the theoretical framework of the subject, global geopolitical evolution and shifts in power space, the roles of major powers and their geo-strategies, as well as China’s surrounding geopolitical environment.  相似文献   

7.
From 2020 to 2030, accelerating the “citizenization” of the migrant population is key to promoting urbanization and achieving common prosperity. The urbanization rate of the registered population in China is roughly 18% lower than that of permanent residents. The pressure of the ageing population and the lack of a labor force have caused big cities to introduce relevant policies to attract talent, and the citizenization process needs to be improved urgently, with a particular focus on megacities. The transformation in the number of registered residents in megacities varies greatly, and there is a lack of research on this topic, which makes it an important academic issue. Using both natural and social perspectives, we selected concise indicators and combined the possibility-satisfiability model to estimate the urbanization transformation gap of annual household registration. Further, we constructed a panel data model to empirically analyze the different factors leading to the gap of household registration in megacities. The main factors affecting the transformation of the registered population in megacities are medical services, as well as educational resources and the urban water supply. It is urgent for urban and rural administrators to change the current passive and rigid institutional mechanisms and to ensure flexible, normal governance.  相似文献   

8.
普惠金融对降低贫困和促进发展成果分享具有重要意义,是国际金融地理学的重要研究议题。论文基于2005—2021年中国知网CNKI数据库3421篇核心期刊论文,利用知识图谱可视化技术分析了中国普惠金融研究的基本特征和热点演化,结果表明:(1)学术成果经历缓慢增长、快速增长、加速增长3个阶段,研究热点经由金融排斥、普惠金融到数字普惠金融的演化,其中农村、区域差异、空间格局及发展效应是各阶段的共同关注;(2)国内普惠金融研究具有学科交叉性、包容性、开放性,多学科的参与推动着普惠金融研究的蓬勃发展,在学科交叉融合过程中,不同学科又有各自的关注点;(3)基于金融地理学视角,提出普惠金融发展的空间过程、地方普惠金融发展的文化经济因素与关系网络、普惠金融的发展效应、金融科技的空间性及其潜在影响等未来研究议题。  相似文献   

9.
Since the implementation of the economic reform and opening up policy in 1978,China has miraculously created long-term high-speed economic growth,but has also had to face the problem of excessive consumption of resources as well as an intensification of en-vironmental pollution.As a result,China is now facing a slowdown in development.China must maintain a certain speed of development to realize its goal of being a powerful nation,and becoming a developed country by 2050.To this end,China is facing a transformation of its economic development.There is a need to agree on an expected economic growth rate,along with the corresponding development modes or means of regulation in the medium-and long-term periods.This study developed a systematic-dynamic model to simulate the cou-pling relationship between economic growth,development modes,and the environmental supply system,and explored the possible options for future economic growth as well as the resource use and environmental protection requirements (the main factors).The results showed that to achieve the development goal of becoming a developed country by 2050,while maintaining a good ecological environment,the suitable growth rate for China's econ-omy is 3.8%-6.3%.Within this range,a growth rate of 3.8%-4.4% was found to be relatively safe,while a growth rate of 4.4%-6.3% required further technical progress.This study pro-vides an early warning in regard to China's environmental and development status.The study was a response to the "Future Earth" framework document and,in terms of development speed,it developed a theoretical system for the determination of resource and environmental carrying capacity (RECC).  相似文献   

10.
《Urban geography》2012,33(10):1443-1466
ABSTRACT

Set against the wider background of global suburbanization, this paper contributes to the emerging literature on the formation of technoburbia in China, and more importantly, the potential “urban contradictions” accompanying this process. Through a bottom-up empirical exploration of the Future Sci-tech City Corridor in Hangzhou and its embedded Featured Town initiative in particular, we observe how the future of technoburbia in China is by no means free from similar challenges in housing affordability and labor stratification. However, these contradictions are managed entirely differently in China. Nevertheless, the highly planned nature of China’s technoburbia also rubs up against political decentralization, demographic change and economic upgrading, implying significant trials and tribulations along the way.  相似文献   

11.
Ma  Bin  Zhang  Bo  Jia  Lige 《地理学报(英文版)》2020,30(9):1387-1400
In this paper,meteorological industry standard,daily mean temperature,and an improved multiple regression model are used to calculate China's climatic seasons,not only to help understand their spatio-temporal distribution,but also to provide a reference for China's climatic regionalization and crop production.It is found that the improved multiple regression model can accurately show the spatial distribution of climatic seasons.The main results are as follows.There are four climatic seasonal regions in China,namely,the perennial-winter,no-winter,no-summer and discernible regions,and their ranges basically remained stable from 1951 to 2017.The cumulative anomaly curve of the four climatic seasonal regions clarifies that the trend of China's climatic seasonal regions turned in 1994,after which the area of the perennial-winter and no-summer regions narrowed and the no-winter and discernible regions expanded.The number of sites with significantly reduced winter duration is the largest,followed by the number of sites with increased summer duration,and the number of sites with large changes in spring and autumn is the least.Spring advances and autumn is postponed due to the shortened winter and lengthened summer durations.Sites with significant change in seasonal duration are mainly distributed in Northwest China,the Sichuan Basin,the Huanghe-Huaihe-Haihe(Huang-Huai-Hai) Plain,the Northeast China Plain,and the Southeast Coast.  相似文献   

12.
IntroductionFlood disasters have been serious since the ancient bines. AJthough we have Strengthened the harnessingofbig rivers since the founding of new Chin4 the threat still edeStS (see FigUre l). The Yellow myer hasbeen well known for its flood disasters since long time %o in China. There more than 1500 river burstShappened to the Yellow hiver in the paSt 2000 or 3000 years. Whereas floods of the Changjiang caverwere comparatively not serious in history, but its flood disasters have …  相似文献   

13.
14.
Progress in China’s climate change study in the 20th century   总被引:2,自引:0,他引:2  
Studies on the 20th century climate change in China have revealed that under the background of global warming over the past century, climate in China has also experienced significant change with mean annual temperature increased by about 0.5 °C. More reliable results for the latter part of the 20th century indicate that the largest warming occurred in Northwest China, North China and Northeast China, and the warming in winter is most significant. Although no obvious increase or decrease trends were detected for mean precipitation over China in the past half century, regional differences are very distinct. In the middle and lower reaches of the Yangtze River, precipitation increased, while that in the Yellow River Basin markedly decreased. Studies suggest that climate change in China seems to be related not only with the internal factors such as ENSO, PDO, and the others, but also with the anthropogenic effects such as greenhouse gas emissions, and land use. The future climate change studies in China seem to be important in narrowing understanding the nature of China’s climate change and its main causes, since it is significant for projection and for impact assessment of climate change in the future.  相似文献   

15.
Progress in China’s climate change study in the 20th century   总被引:4,自引:0,他引:4  
IPCC (2001) pointed out that the earth's climate was undergoing a remarkable change with characteristics of global warming over the past 100 years. The latest research showed that the global mean surface temperature has increased by about 0.6 oC since 1861. It is very likely that the last 20 years in the 20th century was the warmest decades. The Northern Hemisphere temperatures in the 20th century appeared to have been unprecedented during the past millennium. The research also indicates th…  相似文献   

16.
The Resourcing Future Generations (RFG) program is a global strategy proposed by the International Union of Geological Sciences to meet global demand for natural resources. The Belt and Road (B&R) initiative of China provides a great opportunity for promoting the RFG across much of the Eurasian continent. The countries covered by the B&R initiative are mostly low-income economies. With rapid developments of economy and infrastructure construction, these countries are set to have huge demands for mineral resources in the future. However, the proven mineral reserves in this region are too limited, and the region’s overall level of metal recycling is far from optimistic. These countries are expected to have obstacles in meeting future demands. However, the regional Tethyan metallogenic domain and Central Asia metallogenic district are key areas for new discoveries of mineral resources, possessing a variety of mineral resources with a positive prospecting potential. The B&R initiative of China provides favorable opportunity for mutual beneficial cooperation to improve regional exploration and prospecting through geological mapping, inter-comparison study on Tethyan metallogenic domain, joint assessment of mineral resource potentials, joint training of geological engineers and workers and building information systems.  相似文献   

17.
ABSTRACT

Existing theory of urban transformation under neoliberalization describes cities as the institutional arena in and through which neoliberal strategies of urbanism emanate and are contested. Emphasis is placed on the interaction between state and market without paying adequate attention to their internal dynamics. This study of urban transformation in the Beijing metropolis identifies a distinct trajectory whereby commodification of urban land has been actively pursued in response to the decentralization of developmental responsibilities and recentralization of tax revenue collection instituted by the central state. An urban development strategy is practiced whereby land commodification, city planning, and mega event hosting are integrated and mutually reinforcing. The research shows a pattern of land commodification and development dominated by newly developed construction land in the near suburbs, and reveals a picture of increased spatial inequality and intensified social discontent as a consequence of city-centered land development. Contrary to popular perception of the state and market as diametrically opposed principles of political organization, the Chinese state is found to have transformed and reshuffled itself to embrace and take advantage of the market for its developmental agenda.  相似文献   

18.
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   

19.
In this study, we developed a theoretical framework to analyze the provincial differences in eco-compensation and selected appropriate measurement methods to investigate these differences in the operation of the eco-compensation framework. Via the use of the coefficient of variation, Atkinson index, and Gini coefficient, we investigated the overall differences in Chinese provincial eco-compensation time series data from 2004 to 2014 and studied the driving mechanism underlying these differences. The results showed that: (1) The provincial eco-compensation standard has geographical features. For example, the provinces crossed by the “HU Huanyong Line”, or located to its northwestern side, have obtained extensive eco-compensation. (2) There was a trend for differences in eco-compensation to increase over time, but with some fluctuations in 2006, 2009, and 2014 as shown by the coefficient of variation, in 2005, 2007, 2011, 2013, and 2014 as shown by the Gini coefficient, and in 2007, 2008, 2011, and 2012 as shown by the Atkinson index. (3) Time series curves indicated that while the signals from the three metrics (coefficient of variation, Atkinson index, and Gini coefficient) differ in a short-term analysis, they show the same tendency in the longer term. The results indicate that it is necessary to evaluate the differences in eco-compensation at the provincial level over a long period of time. (4) Via the calculation of the virtual Gini coefficient, we found that among the factors that influence provincial differences in eco-compensation, the economic value of eco-resources played the decisive role, explaining more than 73% of the difference. The cost of environmental pollution abatement was the second most important factor, accounting for more than 19% of the difference. The input to environmental pollution abatement had the least influence, accounting for less than 8% of the difference. The results agreed with those obtained from other studies, and could be used as a reference by policy makers.  相似文献   

20.
The influence of monsoon climatic characteristics makes the tropics of China different from those of other parts of the world. Therefore, the location of the northern boundary of China’s tropical zone has been one of the most controversial issues in the study of comprehensive physical regionalisation in China. This paper introduces developments in the study of the northern boundary of China’s tropical zone, in which different scholars delimit the boundary with great differences based on different regionalisation objectives, indexes, and methods. The main divergence of opinion is found in different understandings of zonal vegetation, agricultural vegetation type, cropping systems, tropical soil type and tropical characteristics. In this study, we applied the GeoDetector model, which measures the spatial stratified heterogeneity, to validate the northern boundaries of the tropical zone delimited by six principal scholars. The results show that the mean q-statistic value of the higher latitude boundary delimited by Ren Mei’e is the largest (q=0.37), suggesting that, of the rival views, it best reflects the regional differences between China’s tropical and subtropical zones, but it is not necessarily suitable for guiding the development of tropical agriculture. The mean values of the q-statistics of Zheng Du’s line and Yu Xianfang’s line around the Leizhou Peninsula at a lower latitude were smaller, at 0.10 and 0.08 respectively, indicating that the regional differences were smaller than those of Ren Mei’e’s boundary. Against the background of global climate change, the climate itself is changing in fluctuation. It is, thus, worth our further research whether the northern boundary of the tropical zone should not be a fixed line but rather should fluctuate within a certain scope to reflect these changes.  相似文献   

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