【作者】 姜庆彪；

【导师】 赵秀海；

【作者基本信息】 北京林业大学 ， 生态学， 2012， 硕士

【摘要】 在树轮学研究中通常使用去趋势方法移除非气候因子的影响。因此,树轮宽度与气候的相关被认为不受树木径级的影响。然而大量生理学研究表明树木生理过程与径级密切相关,而气候因子正是通过作用于树木的生理过程对树木生长产生影响。该文通过建立黑里河(HL)、克旗(KQ)、松山(SS)及宁夏(NX)四个样点的两个径级油松(Pinus tabulaeformis)年表,研究了不同径级油松敏感度的差异,建立了年表与气候因子的相关关系并探讨了干旱对不同径级油松径向生长的影响。油松气候—生长相关关系是通过相关与响应分析建立的,干旱对油松径向生长的影响是通过Superposed Epoch Analysis (SEA)方法建立的。主要结果如下：1)随取样地点的不同,平均敏感度与胸径的相关关系不同。在HL与KQ样点,平均敏感度与胸径呈线性负相关(P<0.001),而在NX与SS样点二者无显著相关关系。同一地点不同径级油松年轮宽度年表均达到极显著相关(P<0.01)。2)取样地点油松径向生长与降水呈正相关而与夏季温度呈负相关。春夏季的气候是影响油松径向生长的主要因子。温暖湿润的春季及凉爽多雨的夏季会形成宽轮。降水对油松径向生长的影响具有明显的“滞后效应”。3)在干旱年份,HL与KQ油松的径向生长量表现出显著的降低(P<0.01),在干旱后1年径向生长量恢复正常。在HL,干旱年小径级油松的生长降低量显著高于大径级油松(P<0.01),且干旱后的生长恢复量显著高于大径级油松(P<0.01)。在KQ,干旱年不同径级油松的径向生长的降低量及干旱后的生长恢复量无显著差异。从结果可以得出：1)在HL与KQ,油松敏感度与胸径显著相关且小径级油松具有更高的敏感度,而在SS及NX则不具有显著相关。2)油松对干旱响应敏感,在干旱年份油松径向生长显著降低,且在1年的时间恢复生长。在HL油松对干旱的响应具有显著差异而在KQ则无差异。不同径级油松的敏感度及其对干旱的响应均受到当地水热条件的影响。油松的气候—生长关系受到径级的影响,因此在树轮学取样中应该考虑径级因素以得到更全面的结果。更多还原

【Abstract】 In dendrochronological studies, the effect of non-climatic signals is always removed from the series of tree-ring widths. Therefore it is generally assumed that the climate-growth relationship is class diameter independent. However intensive physiology studies have shown that tree’s physiological process is related to diameter, while tree’s growth is affected by climatic factors via physiological process. In this paper we built chronologies of two diameter classes of Pinus tabulaeformis from4sample sites:Heilihe(HL), Keqi(KQ), Songshan(SS) and Ningxia(NX). We analyzed differences of sensitivity between two groups of trees, built climate-growth relationships and discussed whether drought differentially affected the ring-widths in these groups. Climate-growth relationships were analyzed using the correlation and response functions and the effect of drought on trees’growth was evaluated by superposed epoch analysis (SEA) using nine drought years. The results showed that:1) The relationship between mean sensitivity and DBH were different in different sites. The relationship was a significantly negative correlation in sites HL and KQ while there were no significant correlation in sites NX and SS. Chronologies of different diameter classes in the same site were significantly correlated(P<0.01).2) Growth of P. tabulaeformis in all sites were positively correlated to precipitation and negatively correlated to temperature in summer. Climate in spring and summer were most important factors that affecting growth of P. tabulaeformis. A warm-wet spring and cool-wet summer enhanced radial growth. There were hysteresis effects of precipitation to radial growth. The ring-widths were significantly positive correlated to September in last year(HL and SS), October in last year(KQ).3) SEA revealed significant growth reduction during drought years as compared to non-drought years (P<0.01) in both tree groups(HL and KQ) and recovered to the level of pre-drought years in one year after drought, indicating drought sensitivity of Chinese pine. In HL, the reductions of small DBH trees were significant higher than the large DBH trees(P<0.01). In KQ, there were no significant differences between the groups. It can be concluded from the results that:1) in the sites HL and KQ, the relationship between sensitivity and DBH was significantly correlated and the sensitivity of small DBH trees were higher. While in site NX and SS there were no significant correlation.2) P. tabulaeformis is drought sensitive species, showed significant reduction in drought years and recovered to normal in one year. The response of radial growth to drought was significant different in site HL while there were no differences in site KQ. The mean sensitivity and responses to drought of different classes were affected by the local climate. The growth-climate relationship were not stable among diameter class, therefore DBH should be considered in sampling procedure to produce unbiased results.更多还原