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.
英文摘要:
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 RCP_(2.6),RCP_(4.5) and RCP_(8.5) scenarios,respectively,while the annual precipitation would have no significant change under climate scenarios except RCP_(4.5),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 RCP_(8.5) scenario. The NPP under the RCP_(8.5) scenario was the highest,followed by the RCP_(4.5) and RCP_(2.6) 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 RCP_(2.6) and RCP_(4.5) scenarios,respectively,implying that this area has the potentiality to be carbon source.