Terrestrial carbon cycle and the global atmospheric CO2 budget are important foci in global climate change research. Simulating net primary productivity （NPP） of terrestrial ecosystems is important for carbon cycle ...Terrestrial carbon cycle and the global atmospheric CO2 budget are important foci in global climate change research. Simulating net primary productivity （NPP） of terrestrial ecosystems is important for carbon cycle research. In this study, a plant-atmosphere-soil continuum nitrogen （N） cycling model was developed and incorporated into the Boreal Ecosystem Productivity Simulator （BEPS） model. With the established database （leaf area index, land cover, daily meteorology data, vegetation and soil） at a 1 km resolution, daily maps of NPP for Lantsang valley in 2007 were produced, and the spatial-temporal patterns of NPP and mechanisms of its responses to soil N level were further explored. The total NPP and mean NPP of Lantsang valley in 2007 were 66.5 Tg C and 416 g？m-2？a-1 C, respectively. In addition, statistical analysis of NPP of different land cover types was conducted and investigated. Compared with BEPS model （without considering nitrogen effect）, it was inferred that the plant carbon fixing for the upstream of Lantsang valley was also limited by soil available nitrogen besides temperature and precipitation. However, nitrogen has no evident limitation to NPP accumulation of broadleaf forest, which mainly distributed in the downstream of Lantsang valley.展开更多
森林净初级生产力(NPP)是衡量陆地碳源/汇的重要参数,准确地估算森林生态系统的NPP,同时通过引入干扰因子以期更加完整地描述生态学过程及其响应是目前森林生态系统碳循环研究的重点。因此,该研究基于北方生态系统生产力(BEPS)模型,结...森林净初级生产力(NPP)是衡量陆地碳源/汇的重要参数,准确地估算森林生态系统的NPP,同时通过引入干扰因子以期更加完整地描述生态学过程及其响应是目前森林生态系统碳循环研究的重点。因此,该研究基于北方生态系统生产力(BEPS)模型,结合遥感数据和气象数据等模拟2003年东北林区NPP;将BEPS模型模拟的结果作为整合陆地生态系统碳收支(In TEC)模型的参考年数据,模拟东北林区1901–2008年的NPP,并在In TEC模型中加入林火干扰数据,模拟大兴安岭地区1966–2008年的森林NPP。结果显示:在1901年,东北林区NPP平均值仅为278.8 g C·m–2·a–1,到了1950年,NPP平均值增加到338.5 g C·m–2·a–1,2008年NPP平均值进一步增加到378.4 g C·m–2·a–1。其中长白山地区的NPP平均值始终最高,大兴安岭次之,小兴安岭始终最低。到了2008年,大、小兴安岭和长白山地区的NPP平均值都有较大涨幅,其中涨幅最高的是长白山地区,达到200–300 g C·m–2·a–1;东北三省中,黑龙江和吉林的NPP平均值和总量都比较高,辽宁相对较低,但相比于1901年的涨幅最高,达到70%;重大火灾(100–1000 hm2)对NPP的影响不是很大,而特大火灾(>1 000 hm2)的影响比较大,使NPP下降幅度达到10%左右,其他火灾年份,NPP增长迅速并保持在较高水平;对火灾面积在100 000 hm2以上的4个年份的NPP进行分析,发现NPP平均值都大幅度下降,其中1987年下降幅度最大,为11%以上。展开更多
基金supported by the National Natu-ral Science Foundation of China (No.40771172 No. 40901223)+1 种基金the Innovative Program of the Chinese Academy of Sciences (No. kzcx2-yw-308)the State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, CAS (SKLLQG0821)
文摘Terrestrial carbon cycle and the global atmospheric CO2 budget are important foci in global climate change research. Simulating net primary productivity （NPP） of terrestrial ecosystems is important for carbon cycle research. In this study, a plant-atmosphere-soil continuum nitrogen （N） cycling model was developed and incorporated into the Boreal Ecosystem Productivity Simulator （BEPS） model. With the established database （leaf area index, land cover, daily meteorology data, vegetation and soil） at a 1 km resolution, daily maps of NPP for Lantsang valley in 2007 were produced, and the spatial-temporal patterns of NPP and mechanisms of its responses to soil N level were further explored. The total NPP and mean NPP of Lantsang valley in 2007 were 66.5 Tg C and 416 g？m-2？a-1 C, respectively. In addition, statistical analysis of NPP of different land cover types was conducted and investigated. Compared with BEPS model （without considering nitrogen effect）, it was inferred that the plant carbon fixing for the upstream of Lantsang valley was also limited by soil available nitrogen besides temperature and precipitation. However, nitrogen has no evident limitation to NPP accumulation of broadleaf forest, which mainly distributed in the downstream of Lantsang valley.
文摘森林净初级生产力(NPP)是衡量陆地碳源/汇的重要参数,准确地估算森林生态系统的NPP,同时通过引入干扰因子以期更加完整地描述生态学过程及其响应是目前森林生态系统碳循环研究的重点。因此,该研究基于北方生态系统生产力(BEPS)模型,结合遥感数据和气象数据等模拟2003年东北林区NPP;将BEPS模型模拟的结果作为整合陆地生态系统碳收支(In TEC)模型的参考年数据,模拟东北林区1901–2008年的NPP,并在In TEC模型中加入林火干扰数据,模拟大兴安岭地区1966–2008年的森林NPP。结果显示:在1901年,东北林区NPP平均值仅为278.8 g C·m–2·a–1,到了1950年,NPP平均值增加到338.5 g C·m–2·a–1,2008年NPP平均值进一步增加到378.4 g C·m–2·a–1。其中长白山地区的NPP平均值始终最高,大兴安岭次之,小兴安岭始终最低。到了2008年,大、小兴安岭和长白山地区的NPP平均值都有较大涨幅,其中涨幅最高的是长白山地区,达到200–300 g C·m–2·a–1;东北三省中,黑龙江和吉林的NPP平均值和总量都比较高,辽宁相对较低,但相比于1901年的涨幅最高,达到70%;重大火灾(100–1000 hm2)对NPP的影响不是很大,而特大火灾(>1 000 hm2)的影响比较大,使NPP下降幅度达到10%左右,其他火灾年份,NPP增长迅速并保持在较高水平;对火灾面积在100 000 hm2以上的4个年份的NPP进行分析,发现NPP平均值都大幅度下降,其中1987年下降幅度最大,为11%以上。
