Interdependent Dynamics of LAI-ET across Roofing Landscapes:the Mongolian and Tibetan Plateaus

基于不同景观的LAI-ET时空协同效应研究——以蒙古高原和青藏高原为例（英文）

The Mongolian and Tibetan Plateaus have experieneed warming higher than the global average in recent decades, resulting in many significant changes to ecosystem structures and functions. Among items that show change are the leaf area in dex (LAI) and evapotranspirati on (ET), both of which play a fun dame ntal role in shapi ng many causes and conseque nces of la nd surface processes and climate. This study examines the spatiotemporal changes of the LAI and ET and their relationships on these two roofing Iandscapes. Based on the MODIS products from 2000 through 2014, we found that there existed a gen era I positive relationship betwee n LAI and ET on the Mongolia Plateau (MP), while synergy did not exist on the Tibetan Plateau (TP). Overall, 49.38%(50.62%) of land areas on the TP experieneed significant increases (decreases) in LAI, while on the MP the percentages of increase and decrease were 94.92%(5.09%). For ET, the increased land area was 21.70%(124100 km^2) on the TP and 88.01%(341600 km^2) on the MP. More importantly, the relationships varied substantially across space and over time, with mismatches found in some parts of the Iandscapes. Additional observational investigations and/or experime ntal research are n eeded to explore the relati on ships, including the in flue nces of vegetation characteristics and disturbances.

近几十年来,蒙古高原和青藏高原的增温速度高于全球变暖的平均水平,导致生态系统的结构和功能发生了显著变化。叶面积指数(LAI)和蒸散发(ET)在塑造陆地表面过程和气候方面发挥着重要作用。在文中,我们重点关注LAI和ET的时空变化及其相互关系。基于2000-2014年的MODIS产品,我们发现蒙古高原的LAI和ET之间存在普遍的正相关关系,而青藏高原则没有协同作用。总体而言,青藏高原LAI的显著增加(减少)区域占总面积的49.38%(50.62%),蒙古高原则为94.92%(5.09%);青藏高原ET增加区域面积占总面积的21.70%(124.10×10~3 km^2),蒙古高原为88.01%(341.60×10~3 km^2)。更重要的是,随着时间的推移,这种关系在整个空间中发生了很大的变化,并且在景观的某些部分发现了不匹配。需要通过观测和/或实验研究来探讨这些关系,包括植被特征及其干扰的影响。