关键词: 幼虫, 分泌物, 华北大黑鳃金龟, 植物根系, 引诱作用

Abstract: In order to clarify the stability of the tree growth response to the climate and its elevation difference, this study dendrochronologically developed chronologies of spruce (Picea jezoensis var. komarovii) growing at the elevation of 1200 m (low), 1400 m (middle) and 1600 m (high) on the northern slope of Changbai Mountain, and then explored the relationship of radial growth and climate and its dynamics. The results showed that spruce generally had a low climate sensitivity (0.12-0.16). Comparatively, spruce at low altitude had higher climate sensitivity. The radial growth of spruce was significantly positively correlated with mean maximum temperature in May at the three elevations. Additionally, spruce at middle and low elevations was significantly negatively correlated with the precipitation in May. However, the correlation between spruce’s radial growth and the climate was not stable. Since 1986, mean maximum temperature in May displays a decreasing trend, which made the correlation between spruce’s growth and climate decline. The breakpoints of correlation coefficients from significant to nonsignificant occurred at 11.8 (mean temperature in May) and 19.9 ℃ (mean maximum temperature in May), respectively. The increased correlation between growth and climate was mainly affected by the increasing precipitation in May in recent years, and the breakpoint occurred at 72.2 mm. This study provides a reference date for climate reconstruction and the prediction of spruce’s growth under climate change.

Key words: root, Holotrichia oblita, exudate, larva, stimulation