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The primary factor controlling C/C relative abundance in terrestrial ecosystem since the Last Glacial has been widely debated. Now more and more researchers recognize that climate, rather than atmospheric CO concentration, is the dominant factor. However, for a specific area, conflicting viewpoints regarding the more influential one between temperature and precipitation still exist. As temperature and precipitation in a specific area usually not only vary within limited ranges, but also covary with each other, it is difficult to get a clear understanding of the mechanism driving C/C relative abundance. Therefore, systematic analysis on greater spatial scales may promote our understanding of the driving force. In this paper, records of C/C relative abundance since the Last Glacial on a global scale have been reviewed, and we conclude that: except the Mediterranean climate zone, C plants predominated the high latitudes during both the Last Glacial and the Holocene; from the Last Glacial to the Holocene, C relative abundances increased in the middle latitudes, but decreased in the low latitudes. Combining with studies of modern process, we propose a simplified model to explain the variations of C/C relative abundance in global ecosystem since the Last Glacial. On the background of atmospheric CO concentration since the Last Glacial, temperature is the primary factor controlling C/C relative abundance; when temperature is high enough, precipitation then exerts more influence. In detail, in low latitudes, temperature was high enough for the growth of C plants during both the Last Glacial and the Holocene; but increased precipitation in the Holocene inhibited the growth of C plants. In middle latitudes, rising temperature in the Holocene promoted the C expansion. In high latitudes, temperature was too low to favor the growth of C plants and the biomass was predominated by C plants since the Last Glacial. Our review would benefit interpretation of newly gained records of C/C relative abundance from different areas and different periods, and has its significance in the understanding of the driving mechanisms of C/C variations on longer timescales (e.g., since the late Miocene) with reliable records of temperature and atmospheric CO concentration. [ABSTRACT FROM AUTHOR]

This paper reports a study on reconstructing temperature series for ten regions of China over the last 1000 years with a time resolution of 10 a. The regions concerned are: Northeast, North, East, South China, Taiwan, Central, Southwest, Northwest China, Xinjiang and Qinghai-Tibet Plateau. A variety of proxy data, such as ice core, tree-rings, stalagmites, peat, lake sediments, pollen and historical records, were validated with instrumental observations made in the last 120 years, and applied in the reconstruction of the temperature series. A temperature series for whole China is then established by aver- aging the ten regional series with a weighting proportional to the area of each region. Finally, temperature variations for the last 1000 years are examined, with special focus placed on the characteristics of the Medieval Warm Period (MWP), the Little Ice Age (LIA), and Modern Warming (MW). [ABSTRACT FROM AUTHOR]