北京西山老龄树记载的森林干扰历史

张启, 程雪寒, 王树芝

History of forest disturbance recorded by old trees in Xishan Mountain, Beijing

ZHANG Qi, CHENG Xue-Han, WANG Shu-Zhi

图1 北京气象站1952-2020年间的气象资料。P, 降水量; PDSI, 帕尔默干旱指数; T, 平均气温。

Fig. 1 Meteorological data of the Beijing meteorological station from 1952 to 2020. P, annual precipitation; PDSI, palmer drought severity index; T, mean air temperature.