在气候暖干化趋势下,进行森林经营树种对气候变化的响应研究,有助于适宜的经营技术构建以及森林经营对气候变化的应对。选取围场县龙头山林场天然华北落叶松,建立年轮宽度年表,应用相关分析、Mann-Kendall检验、逐步回归等方法,研究华北落叶松径向生长对气候变化的响应。结果表明:1)近60年来,本地区气温显著升高,在1980年发生升高突变;降水量有减少趋势,但变化趋势不明显。2)华北落叶松径向生长受气温与降水的双重影响,与多数气温因子呈显著负相关,与多数降水因子呈显著正相关,当年3,4月份降水是树木径向生长的重要限制因素。3)生长季极端高温与径向生长呈显著负相关,湿润指数与径向生长呈极显著正相关。4)利用当年生长季平均温度及3,4月份降水量和湿润指数模拟华北落叶松径向生长,发现在暖干化趋势下,研究区华北落叶松的生长将呈现减缓趋势。

Under the trend of climate warming and drying,the study on response of forest management tree species to climate change helps contribute to the development of adaptive management technologies and to the reaction to climate change.Natural Larix principis-rupprechtii trees were selected to establish the tree ring width chronology at Longtoushan Forest Farm in Weichang County.Correlation analysis,Mann-Kendall test and stepwise regression were used to analyze the response of radial growth of Larix principis-rupprechtii to climate change.The results indicated that:(1)The temperature in the region has increased significantly with an abrupt change in 1980,and the precipitation has decreased with an unobvious trend for nearly 60 years.(2)The radial growth of Larix principis-rupprechtii was jointly affected by temperature and precipitation,and had significantly negative correlation with most temperature factors and significantly positive correlation with most precipitation factors.The precipitation in March and April was an important limiting factor for radial growth in this region.(3)There was significant negative correlation between extreme high temperature and radial growth in the growing season.The wetness index was significantly positively correlated with radial growth.(4)The prediction model of tree ring width growth was constructed using average temperature of current growing season,total precipitation in March and April,and wetness index as independent variables.It was found that the radial growth of Larix principis-rupprechtii would become slower with the warmer and drier climate.