陕西省油松林生产力动态及对未来气候变化的响应

Dynamic change of Pinus tabuliformis forest productivity and its response to future climate change in Shaanxi Province,China

本研究利用LPJ-GUESS模型,分析了陕西省油松林在未来时期(2015—2100年)不同气候情景下净初级生产力(NPP)的变化趋势.结果表明:在未来时期,研究区温度在RCP_(2.6)、RCP_(4.5)和RCP_(8.5)情景下将分别以0.12、0.23和0.54℃·10 a^(-1)的速率显著升高;降水在RCP_(2.6)和RCP_(8.5)情景下无显著变化,在RCP_(4.5)情景下将以14.36 mm·10 a^-1的速率显著增加.与历史时期(1961—1990年)相比,研究区油松林的NPP在未来时期将升高1.6%~29.6%;在RCP_(8.5)情景下21世纪末期(2071—2100年)油松林NPP将会升高45.4%;不同情景下油松林NPP表现为RCP_(8.5)>RCP_(4.5)>RCP_((2.6)).在未来时期,陕北地区油松林NPP在RCP_(2.6)和RCP_(4.5)情景下将分别以41.00和21.00 g C·m-2·10 a^(-1)的速率下降,该区油松林有变为碳源的可能.

This study analyzed the dynamics of net primary productivity （NPP） of Pinus tabuliformis forest under future climate scenarios in Shaanxi Province during 2015-2100, using a dynamic vegetation model （LPJ-GUESS）. The results showed that in the 2015-2100 period, annual mean temperature of this region would significantly increase by 0.12, 0.23 and 0.54 ℃ . 10 a-1 under RCP2.6, RCP4.5 and RCP8.5 scenarios, respectively, while the annual precipitation would have no significant change under climate scenarios except RCP4.5, under which it would significantly increase by 14.36 mm. 10 a-1. Compared with the NPP of P. tabuliformis forest in the historical period （1961-1990）, it would increase by 1.6%-29.6% in the future period, and the enhancement could reach 45.4% at the end of this century （2071-2100） under RCP85 scenario. The NPP under the RCP85 scenario was the highest, followed by the RCP45 and RCP2.6 scenarios. During 2015-2100, the NPP in the northern Shaanxi region would significantly decrease with the rate of 41.00 and 21.00 g C . m-2 . 10 a-1 under the RCP2.6 and RCP45 scenarios, respectively, implying that this area has the potentiality to be carbon source.