| Korean pine is a valuable native tree species in northeast China. In recent decades, the temperature in Heilongjiang Province is increasing obviously and the Korean Pine has declined seriously. The human disturbance may mainly accounts for the decline, but the climate change also plays an important role in this process. Therefore, to develop the climate response analysis of Korean Pine ring and discussion on global warming to the declining of Korean Pine is of great meaning. By taking response analysis on the tree-ring from the four sample areas, Heihe, Liangshui, Wuying and Mudanjiang, of the Korean Pine distribution region in Heilongjiang Province, this thesis makes analysis on the main climate factors restricting the growth of Korean Pine in Heilongjiang and the difference of response means of old and young trees, and makes discussion on influence of global warming on growth of Korean Pine distributed in different latitudes in Heilongjiang. It correctly establishes the standard chronology in different areas through cross-dating, and separately makes response relationship analysis of climate factors, such as average monthly temperature, average monthly rainfall, monthly maximum temperature and minimum temperature, in local meteorological stations. The results show that, Heihe area is significantly correlated to the temperature of December in the previous year, Wuying area is significantly correlated to the temperature of October in the previous year and Liangshui area is significantly correlated to the temperature of July in the previous year. The lower the latitude is, the less correlated to temperature and the more correlated to rainfall. Mudanjiang area is correlated to rainfall of October in the last year and July of this year.The samples were divided into A (young) and B (old) groups according to age size(n= 15) in each sample sites, then were made into standard chronologies to do response relation analysis with local meteorological data, which compared the response difference between different ages in the same region, as well as the response difference between the four sampling places. Consequence is that the climate of the Heilongjiang Province was affected by latitude location, the monsoon circulation, and topographic factors and so on. The four sample areas are widely across long latitude, which result the heat difference both in time and spatial. For four distributions, the Korean pine in group A are all young samples which were made chronologies that have same relationship with the overall standard chronologies of climate response while group B are all old samples that have strong relationship with winter temperature in the previous year. Mudanjiang is influenced by rainfall because of its location, and all chronologies of group A and B show little difference with the general ones in four sites separately.The average temperature of four sampling sites presented obviously rising around 1984, and the speed increased approximately 1.2℃in recent 10 years compared with previous 40 years. The Korean pine of Heihe and Mudanjiang present the trend of decline while the performance of WuYing and LiangShui which belong to Yichun shows very gentle. By comparing the relationship between the result written by D'Arrigo who reconstructed the temperature of the Northern Hemisphere in 2006 with the Korean pine's growth trend of four sample sites has further proven this conclusion of the experiment that the phenomenon of Korean pine's decline happened on the edge of distributing areas (Heihe and Mudanjiang) while the other two places remained quite well accounting for their central locations. Global warming affects the marginal areas much more than the central ones since distribution of Korean pine in Heilongjian province is significantly correlated with temperature. |
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