在最近一期的《Science》研究论文中，美 国蒙大拿大学的赵茂盛博士（北京师范大学地理学与遥感科学学院1995届本科毕业生）与Steven Running等科研人员报告说，全世界陆地生态系统净初级生产力（NPP）在过去10年（2000-2009）中有所下降，从而逆转了过去20年 （1982-1999）的趋势。该研究基于MODIS卫星遥感数据，并结合了相关的气候资料，调查了从2000-2009年的全球陆地净初级生产力和气候 的变化。研究发现全球NPP在过去10年中略有下降，而大尺度的区域性干旱是导致NPP降低的重要原因。
Drought-Induced Reduction in Global Terrestrial Net Primary Production
from 2000 Through 2009
Maosheng Zhao* and Steven W. Running
Terrestrial net primary production (NPP) quantifies the amount of atmospheric carbon fixed by plants and accumulated as biomass. Previous studies have shown that climate constraints were relaxing with increasing temperature and solar radiation, allowing an upward trend in NPP from 1982 through 1999. The past decade (2000 to 2009) has been the warmest since instrumental measurements began, which could imply continued increases in NPP; however, our estimates suggest a reduction in the global NPP of 0.55 petagrams of carbon. Large-scale droughts have reduced regional NPP, and a drying trend in the Southern Hemisphere has decreased NPP in that area, counteracting the increased NPP over the Northern Hemisphere. A continued decline in NPP would not only weaken the terrestrial carbon sink, but it would also intensify future competition between food demand and proposed biofuel production.
Fig. 1 Interannual variations from 2000 through 2009 in anomalies of annual total global terrestrial NPP (green circles) and inverted global atmospheric CO2 annual growth rate [red squares and (14)]. Global average annual total NPP is 53.5 Pg C/yr.
Fig. 2 Spatial pattern of terrestrial NPP linear trends from 2000 through 2009 (SOM text S1) (8, 10).
摘编人：周涛
