Chen Zhi
Synthesis Research Center of Chinese Ecosystem Research Network, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
Ying Yong Sheng Tai Xue Bao. 2019 May;30(5):1625-1632. doi: 10.13287/j.1001-9332.201905.033.
Understanding changes in vegetation productivity and carbon use efficiency and their responses to climate change is significant to accurately assess and predict regional carbon budget in Northeast forest area, a region being an important carbon sink and sensitive to global change. Based on MODIS monitoring data and vegetation type distribution data, I analyzed the spatiotemporal varia-tions of ecosystem productivity (net primary productivity (NPP), gross primary productivity (GPP)) and carbon use efficiency (NPP/GPP) of Northeast forest from 2000 to 2015. Results showed that the average NPP and GPP were 346.4 and 773 g C·m·a, respectively, and the average NPP/GPP was 0.45 during 2000 and 2015. NPP and GPP of different forest types were following the order: coniferous and broad-leaved mixed forests > deciduous broad-leaved forests > coniferous forests, while the difference in NPP/GPP was not significant among different forest types. NPP and GPP were high in Southeast part and low in Northwest part. From 2000 to 2015, the NPP, GPP and NPP/GPP of Northeast forest showed a fluctuating increase, suggesting the carbon sequestration capacity was gradually enhanced. However, the trends and rates of NPP, GPP and NPP/GPP showed spatial variation. NPP, GPP and NPP/GPP increased significantly in the southern part of the Daxing'anling while decreased significantly in the northern part of the Daxing'anling, and showed a weak increasing trend in the rest of Northeast forest. The increase of annual precipitation was the main factor driving the fluctuating increase of NPP, GPP and NPP/GPP in Northeast forest.
了解植被生产力和碳利用效率的变化及其对气候变化的响应，对于准确评估和预测东北林区的区域碳收支具有重要意义。东北林区是重要的碳汇地区，对全球变化较为敏感。基于MODIS监测数据和植被类型分布数据，我分析了2000年至2015年东北森林生态系统生产力（净初级生产力（NPP）、总初级生产力（GPP））和碳利用效率（NPP/GPP）的时空变化。结果表明，2000年至2015年期间，平均NPP和GPP分别为346.4和773 g C·m·a，平均NPP/GPP为0.45。不同森林类型的NPP和GPP排序为：针阔混交林＞落叶阔叶林＞针叶林，而不同森林类型之间NPP/GPP的差异不显著。NPP和GPP在东南部较高，在西北部较低。2000年至2015年，东北森林的NPP、GPP和NPP/GPP呈波动增加趋势，表明其碳固存能力逐渐增强。然而，NPP、GPP和NPP/GPP的变化趋势和速率存在空间差异。大兴安岭南段的NPP、GPP和NPP/GPP显著增加，而大兴安岭北段则显著下降，东北森林其他地区呈微弱增加趋势。年降水量增加是驱动东北森林NPP、GPP和NPP/GPP波动增加的主要因素。
