Mismatch in elevational shifts between satellite observed vegetation greenness and temperature isolines during 2000–2016 on the Tibetan Plateau

作者：Shuai An, Xiaolin Zhu, Miaogen Shen, Yafeng Wang, Ruyin Cao, Xuehong Chen, Wei Yang, Jin Chen, Yanhong Tang · 发表于：Global Change Biology · 年份：2018 · DOI：10.1111/gcb.14432 · 被引用次数：93 · 研究领域：Remote Sensing in Agriculture、Species Distribution and Climate Change、Plant Water Relations and Carbon Dynamics

Climate warming on the Tibetan Plateau tends to induce an uphill shift of temperature isolines. Observations and process-based models have both shown that climate warming has resulted in an increase in vegetation greenness on the Tibetan Plateau in recent decades. However, it is unclear whether the uphill shift of temperature isolines has caused greenness isolines to shift upward and whether the two shifts match each other. Our analysis of satellite observed vegetation greenness during the growing season (May-Sep) and gridded climate data for 2000-2016 documented a substantial mismatch between the elevational shifts of greenness and temperature isolines. This mismatch is probably associated with a lagging response of greenness to temperature change and with the elevational gradient of greenness. The lagging response of greenness may be associated with water limitation, resources availability, and acclimation. This lag may weaken carbon sequestration by Tibetan ecosystems, given that greenness is closely related to primary carbon uptake and ecosystem respiration increases exponentially with temperature. We also found that differences in terrain slope angle accounted for large spatial variations in the elevational gradient of greenness and thus the velocity of elevational shifts of greenness isolines and the sensitivity of elevational shifts of greenness isolines to temperature, highlighting the role of terrain effects on the elevational shifts of greenness isolines. The mismat...