Abstract: Based on the 1961-2008 daily meteorological data from 273 stations, and in combination with the simulated temperature and precipitation data under future climate scenario (SRES A2), the climate adaptability of citrus in subtropics of China was studied by using crops climate adaptability model. The variation of citrus climate adaptability was dominated by temperature, and its spatial pattern was basically consistent with the variation of temperature adaptability. Under the future climate scenario, the variation of citrus climate adaptability was approximately in latitudinal distribution, appearing as the turn from descending to ascending with increasing latitude, and could be divided into four types, i.e., high descending type, low descending type, low ascending type, and high ascending type. On the whole, the line of Wenzhou-Jinhua-Pucheng-Leping-Yingshan-Wuhan-Shimen-Jishou-Wugang-Tongdao-Dushan-Wangmo-Guangnan-Pingbian-Lancang could be served as the boundary for the descending and ascending of citrus climate adaptability. In the south of the line, the adaptability was somewhat descending; in the north of the line, the adaptability was somewhat ascending. In addition, there was a greater ascending in the citrus climate adaptability in the west subtropics.

Key words: Straw returning, Microbial characteristics, Soil fertility, Tibet