哈巴雪山高山松径向生长对气候变化的响应

Radial Growth Responses of Pinus densata to Climate Change in Haba Snow Mountain,Southwest China

基于树木年轮学方法,在哈巴雪山海拔上、下限采集高山松年轮样本,建立差值年表并分析其与气候因子关系,以揭示影响该区域高山松(Pinus densata)径向生长的主要气候因子。结果表明:海拔上限高山松径向生长主要受上年8月水热状况影响,还与当年3月平均最高温呈显著正相关、与5月平均温和6月降水均呈显著负相关;海拔下限高山松径向生长主要受当年5月水热状况影响,还与上年12月降水呈显著正相关;哈巴雪山高山松径向生长与气候因子关系较为稳定。通过对横断山区树轮研究的补充,可为未来气候变化下森林保护提供理论依据。

Based on the dendrochonological method,we collected tree ring samples at upper and lower distributional limits of Pinus densata in Haba Snow Mountain to reveal the key climatic factors affecting tree radial growth by studying the relationship between residual chronologies and climatic factors.The results showed that radial growth of P.densata at the upper distributional limits was mainly affected by the hydrothermal condition in previous August,its growth was also significantly correlated with monthly maximum temperature in current March (positive),monthly mean temperature in current May (negative),and precipitation in current June (negative). At lower distributional limits,hydrothermal condition in current May was the main factor affecting its radial growth,while precipitation in December of previous year also promoted its growth.The relationship between the radial growth of P.densata and climate factors was stable.This study is a favorable supplement to the tree ring research in Hengduan Mountains,and it can also provide a theoretical basis for forest protection under future climate change.