关键词: 主林层, 更新层, 梭梭人工林

Abstract: To reveal the coupling effects of regional temperature and precipitation on the radial growth of trees in mountainous forests at different elevations, we collected tree cores of typical sample woods from Larix principis-rupprechtiiplantations with similar conditions across four elevations in the Xiaowen Forest Farm of Guandishan forest region and the Pangquangou National Nature Reserve. We established chronology to obtain the annual ring width index and conducted correlation analysis and singleyear analysis combined with regional temperature and precipitation. The results showed that radial growth ofLarix principis-rupprechtii was closely related to regional temperature and precipitation on the four elevations, but with different response mechanisms. At the altitude of 1600 m, annual ring width index was significantly negatively correlated with temperature in April, and positively correlated with precipitation in September. At 1800 m, annual ring width index was significantly negatively correlated with temperature and positively correlated with precipitation in June of last year. At 2000 m, annual ring width index was significantly negatively correlated with temperature in September and precipitation in March. At 2200 m, annual ring width index was significantly positively correlated with temperature and negatively correlated with precipitation in August of last year. With increasing altitude, the temperature decreased and precipitation increased. Moreover, the coupling effect of temperature and precipitation on the radial growth ofLarix principis-rupprechtii was changing. When the altitude reached 2000 m, the increase in precipitation in the growing season altered the coupling effects.

Key words: Haloxylon ammodendron plantation, main stand layer, regeneration layer.