CO_2倍增和气候变化对北京山区栓皮栎林NPP影响研究

应用生物地球化学过程模型BIOME-BGC估算了1977—1992年北京妙峰山栓皮栎（Quercus variabilis）林的净第一性生产力（NPP）,并分析气候对NPP年际变化的影响以及未来气候变化情景下对NPP的影响。结果表明：1977—1992年15年间栓皮栎的NPP（以C计）平均值为340.17g·m-2·a-1,NPP（以C计）变化在143.56～431.56g·m-2·a-1之间,并无明显的整体变化趋势,但表现出明显的年际变化,年际变动率达18%。在这段时间内降水量成为控制栓皮栎林NPP年际变化的主要气候因子。通过设置18种不同未来气候方案进行栓皮栎林NPP模拟表明,CO2浓度加倍会降低栓皮栎林的NPP但降低幅度较小。在CO2浓度不变的情况下,温度升高2.0℃和降水的协同增加以及单个因子的增加都有利于NPP的积累,但协同增加不如单个因子的增加对NPP的积累效应明显;在CO2和气候同时改变的情况下,CO2浓度加倍、温度升高2.0℃和降水的协同增加有利于NPP的积累且协同增加比单个因子的增加对NPP的积累效应明显,但各因子之间交互作用较弱。

The study of the impact of elevated CO2 concentration and climate change on net primary productivity of Quercus variabilis forest in Beijing Mountain Area

A biogeochemical model, BIOME-BGC, was used to estimate NPP（Net Primary Productivity） of Quercus variabilis forest in the Miaofeng mountain and the climate change effect on them during the period of 1977-1992 and climate change scenario in the future. The result showed that the average annual NPP was 340.17 gC·m-2·a-1, Changes in annual total NPP was between 143.56 and 431.56 gC·m-2·a-1, Shows no significant overall trends but significant interannual variation, The precipitation was the key en-vironmental factor controlling the NPP variations during this period of time. By setting eighteen different variations scenario to simulate NPP（Net Primary Productivity）, The result showed that double CO2 would not benefit for NPP. When CO2 concentration fixed,temperature increased by 2.0 ℃w hile precipitation increase and NPP responded positively to them all, However synergistic increased was less favourable than single factor increasesd; When CO2 concentration doubled and climate changed, CO2 concentration doubled、temperature increased by 2.0 ℃ while precipitation increase and NPP responded positively to them all, and synergistic increased was more favourable than single factor increasesd.However, weak interactions between the various factors.