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regional features of pollen R-values in China

Science China Earth Sciences 2024年第1期67卷 295-308页

作者： Jie XIA Jian NI College of Life Sciences Zhejiang Normal UniversityJinhua 321004China Jinhua Mountain Observation and Research Station for Subtropical Forest Ecosystems Jinhua 321004China

Establishing a quantitative relationship between modern pollen and vegetation remains a pivotal but intricate pursuit within the field of Quaternary *** R-value,a well-established and traditional metric characterized by its simplicity and direct applicability,serves to calibrate the nonlinear disparities between surface pollen and modern *** study entails the construction of a comprehensive pollen R-value dataset for China derived from R-values published between 1987 and *** dataset,compiled after rigorous screening,calibration,and standardization processes,encompasses 898 modern pollen sampling sites and 2115 pollen R-value data entries,encapsulating 152 pollen taxa spanning 65 families and 113 *** the extracted R-values yielded the following insights:(1)A macrospatial analysis validates previously established knowledge at a site-specific ***,pollen R-value variations across China are statistically *** two-thirds of pollen taxa exhibit underrepresentation(e.g.,Taxodiaceae,Corylus,Nitraria,Tamarix,Cyperaceae,Poaceae,and Fabaceae),while the remaining one-third display overrepresentation(e.g.,Pinus,Picea,Betula,Ephedra,Chenopodiaceae,and Artemisia).The degree of underrepresentation surpasses that of overrepresentation,and the representation patterns of Castanea,Quercus,Polygonaceae,and Asteraceae are contingent upon vegetation types.(2)Pollen R-values follow distinct spatial distribution patterns within *** the woody vegetation region of eastern China,R-values progressively decline from north to south,correlating with rising temperatures and ***,in herbaceous vegetation regions of northern and western China,R-values decrease from east to west and from northeast to southwest,corresponding to increased ***,pollen R-values manifest variation contingent on pollen taxa,vegetation types,and climatic regions,even differing for the same taxa across varying

关键词： Pollen R-value Modern pollen-vegetation relationship regional pattern Variability Paleovegetation reconstruction

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The changing regional distribution of grain production in China in the 21st century

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Journal of Geographical Sciences 2006年第4期16卷 396-404页

作者： YIN Peihong FANG Xiuqi TIAN Qing MA Yuling School of Geography Beijing Normal University Beijing 100875.China National Disaster Reduction Center of China Beijing 100053 China

This paper examines the changing regional distribution of grain production in China. Based on the analysis of data from county statistics for the period 2000-2003, major differences in the main grain-output regions in China can be observed. The main grain-producing areas have shifted from the south to the north of China. New grain production regions have been also added to westem China since the late 1990s. The per capita grain consumption in one third of China＇s main grain-producing counties has fallen below 400 kg; most of these areas are located in southern China. In the new millennium, Northeast China, the central-south North China, and the add and semi-arid regions of Northwest China produced three quarters of the surplus grains. Most of these areas are located in regions susceptible to environmental change. The amount of grain production in these regions shows high fluctuations. It is argued here that *** studies of recent environmental changes as well as a risk assessment of China＇s food security in main grain-output regions are needed.

关键词： grain production main grain-output regions regional pattern regional differences China

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Historical Evolution of Relationship between China and the Gulf Region

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Asian Journal of Middle Eastern and Islamic Studies 2016年第1期10卷 1-25页

作者： LIU Zhongmin Middle East Studies Institute Shanghai International Studies University

The Gulf region is in unique geo-political *** relationship between China and the Gulf region is deeply impacted by the international system and regional patterns,as well as the adjustments of China’s own diplomatic *** article tries to analyze the historical evolution of the relationship between China and the Gulf Region from these three *** present,this study is very important for China to rightly understand the strategic environment of the“One Belt and one Road”constructions in the Gulf *** the period of Cold War,the relationship between China and the Gulf region is deeply affected by the Cold War system,which can be proved by the fact during that time,China’s policies toward the Gulf region depended on the relationship between China and the US and the Soviet *** in regional patterns in the Gulf Region and China’s own strategic adjustments also have influence on China’s policies toward the *** the end of the Cold War,many factors,including the changes in the international system,changes in the situation of the Gulf region and the adjustments of China’s development and diplomatic strategies,had influenced the relationship between China and the ***,in this period,the mutual interdependence between China and the Gulf,and the impact of the adjustments of China’s diplomatic strategies on China’s Gulf policies are *** the future,jointly building the“One Belt and One Road”initiative will be the mainstream of the cooperation between China and the Gulf countries.

关键词： Gulf Region International System regional pattern Chinese Diplomacy “One Belt One Road”Initiative

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中国实体经济空间格局优化研究*

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区域与城市经济 2018年第8期

作者：马燕坤陈耀

当前，中国经济“脱实就虚”的问题突出，实体经济发展不仅存在全国性问题，而且存在区域性问题。这些问题主要包括中西部和东北地区较低的市场化水平、中西部地区实体产业盈利空间收窄、实体中小企业融资难、东部地区生产成本上升、区... 详细信息

当前，中国经济“脱实就虚”的问题突出，实体经济发展不仅存在全国性问题，而且存在区域性问题。这些问题主要包括中西部和东北地区较低的市场化水平、中西部地区实体产业盈利空间收窄、实体中小企业融资难、东部地区生产成本上升、区域分割造成的重复建设和产能过剩。优化中国实体经济空间格局，要多渠道降低实体企业的经营成本，推进全国市场一体化，有重点地推动中西部地区新的战略性区域工业化发展，坚定不移地推进供给侧结构性改革和加强实体经济运行监测，从而促进中国实体经济健康可持续发展。

关键词：实体经济区域格局市场一体化 Real Economy regional pattern Market Integration

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