大气增温对长白山林木直径生长的影响

Effect of rise in air-temperature on tree ring growth of forest on Changbai Mountain.

为研究全球性增温对温带森林生态系统的影响，在长白山采集了１３个树种１５５３株１９８２—１９９１年的年轮样品，对照有关气象资料进行了整理分析．结果表明年轮宽度的变化与气温指标的年际变化之间很难找出一一对应的关系．但与１９８２—１９８６年相比，１９８７－１９９１年年平均气温增加０．４８℃，年轮平均宽度增加６．１％．与海拔下降１７６ｍ相应增温１℃，则使相应的年轮宽度增加５０％．以此计算，年均温增加１℃将使阔叶红松林的材积生长增加０．６—３．１ｍ３ｈａ－１·ｙｒ－１．年轮生长的加快可能主要和夜间增温有关．鉴于阔叶树对增温更加敏感，增温还可能使红松林中阔叶树比例增加．

To study the effect of global warming on temperate forest ecosystem, 1553 tree ring samples of 13 tree species planted in 1982 - 1991 on Changbai Mountain are. drilled and theirwidths are analyzed in relation to meteorological data. The results show that few significant relationships can be detected between annual ring width and corresponding annualtemperature regime. However, as compared with the period of 1982-1986, the averageannual air temperature and ring width are increased by 0. 48℃ and 6. 1 %, respectively in1987-1991. When average annual air temperature is increased by 1℃ in corresponding to176m lower elevation, the annual ring width is increased by 50%. Accordingly, 1℃ increment in average annual temperature results in an increase of 0. 6-3. 1m3ha-1· yr-1 in woodvolume growth rate. It is found that the accelerated growth is positively related to thetemperature rise at night rather than at day time. Deciduous tree species responds to temperature rise more sensitively than conifer, and hence, its proportion in the standing composition of deciduous-Korean pine forest will increase accordingly.