气候变化背景下的晋中柏树响应分异研究

Study on Response Differentiation of Cypresses in Jinzhong under Climate Change Background

摘要: 森林作为重要的水源涵养区以及碳循环的主要发生地，对全球气候变化具有较高的敏感度。自上个世纪下半叶以来，全球气候变暖导致了树木生长与气候响应之间的差异，出现了树木生长与气候响应之间的分异和不稳定现象。分异的发现对传统的树轮重构技术和成果提出了挑战，打破了以往对于“均一性”原理的认识。本文以山西晋中地区的林中柏树为样本，运用树轮生态学的方法，对树轮生长特征、树轮生长与主要气候因子之间的相关性进行了研究，并以此为依据，分析树木生长如何响应气候变化，并对其成因进行了深入探讨。结果表明：以温度开始显著上升的1995年为界，树木年轮与气候关系的稳定性变差。晋中地区柏树树轮宽度与当年5，6月份的平均气温存在显著的负相关性，与当年春季的降水量显著正相关，且这两种相关性在1995年以后不断加强，说明气候变暖所导致的春季“干旱胁迫”对树木生长造成很大影响。在1995~2012时段轮宽与4月份相对湿度相关性由负变正，与1月份平均气压负相关增强，与1，2月份日照时数的负相关性减弱，但与4月，12月的负相关性增强。

Abstract: As an important water conservation area and the main place for carbon cycle, forest is one of the important natural resources for human survival, and has a high sensitivity to global climate change. Since the second half of the last century, the phenomenon mainly characterized by global warming has changed the response relationship of tree growth to climate change. The discovery of the divergence phenomenon challenges traditional tree-ring reconstruction methods and results, and affects the global carbon cycle and carbon stock estimation research. In this paper, the cypress trees in the Jinzhong area of Shanxi are taken as samples, and the method of tree-ring ecology is used to study the correlation between tree-ring growth characteristics, tree-ring growth and main climatic factors. How tree growth responds to climate change and its causes are explored in depth. The results showed that the stability of the relationship between tree rings and climate became worse in 1995, when the temperature began to rise significantly. There is a significant negative correlation between the cypress tree ring width and the average temperature in May and June of that year, and a significant positive correlation with the precipitation in the spring of that year, and the two correlations have been strengthened since 1995, indicating that the climate is warming. The resulting “drought stress” in spring had a big impact on tree growth. During the period from 1995 to 2012, the correlation between wheel width and relative humidity in April changed from negative to positive, and the negative correlation with the average air pressure in January increased. Negative correlation increases.