Reforestation can not only sequester carbon, but also change the surface albedo, which is an important means to intervene in climate change. Previous studies focused on the effect of LUCC on surface albedo, yet few studies focused on how the canopy/ understory structure of secondary forest formed after disturbance affects the seasonal variation of forest albedo, and further affects fraction of absorbed photosynthetically active radiation (FAPAR)

Li Shuangtian, a doctoral candidate of the Qingyuan Ker Towers Research Team of the Institute of Applied Ecology, Chinese Academy of Sciences, recently completed a study. They continuously observed forest albedos and FAPAR, as well as seasonal changes in canopy and understory in the temperate forests using Qingyuan Ker Towers (three flux towers in a watershed; natural mixed broadleaved forest, T1; natural Mongolian oak forest, T2; larch plantation forest, T3), and demonstrated a comprehensive analysis.

Solar radiation (SR) and near-infrared (NIR) albedo of broadleaved stands were greater than those of coniferous plantation stand. SR albedo exhibited a seasonal unimodal pattern, peaking around the summer solstice when the solar radiation was strongest. Study highlighted high contribution (>40%) of understory vegetation to the change in forest albedo, in addition to canopy. In addition, they found a co-benefit of FAPAR and albedo in the broadleaved stands (r = 0.69 and 0.93 for T1 and T2, respectively), but the co-benefit was weakened in coniferous plantation stand (r = 0.3 for T3).

Based on these findings, they recommend that understory vegetation management for increasing vegetation green biomass as well as introduction of broadleaf tree species into monocultural coniferous plantation are feasible forest management solutions to increase forest albedo and FAPAR for mitigating climate warming.

This research was funded by National Natural Science Foundation of China, Application and Demonstration Project of Network Security and Informatization Technology, Chinese Academy of Sciences, Central Government Guide the Development of Local Science and Technology Special Fund and the Major Program of Institute of Applied Ecology, Chinese Academy of Sciences. It has recently been published online in Agriculture and Forestry Meteorology entitled "Seasonality of albedo and fraction of absorbed photosynthetically active radiation in the temperate secondary forest ecosystem: A comprehensive observation using Qingyuan Ker Towers".

YUE Qian

Institute of Applied Ecology, Chinese Academy of Sciences

Tel: 86-24-83970317

E-mail: yueqian@iae.ac.cn

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