JOURNAL OF NATURAL RESOURCES ›› 2018, Vol. 33 ›› Issue (1): 27-36.doi: 10.11849/zrzyxb.20161109

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Impacts of Aerosol Direct Radiative Effect on Carbon Cycle in Global Terrestrial Ecosystem

SHAO Si-ya1, 2, ZHANG Jing1, 2, *, ZHOU Li-hua1, 2, QIAO Yan1, 2   

  1. 1. College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China;
    2. Joint Center for Global Change Studies, Beijing 100875, China
  • Received:2016-10-17 Revised:2017-02-23 Online:2018-01-20 Published:2018-01-20

Abstract: The biogeochemical processes in global terrestrial ecosystem are studied using the Community Land Model (CLM), and the impacts of aerosol radiative effects on the carbon cycle in global terrestrial ecosystem are analyzed. Calculations show that the aerosol direct radiative effects caused the global averages of terrestrial gross primary productivity (GPP), net primary productivity (NPP), heterotrophic respiration (RH), autotrophic respiration (RA), and net ecosystem productivity (Reco) to increase in 2007, with significant spatial variations however. For instance, the GPP increased in the mid-west of Africa, the mid-east of China, the southeastern US and the mid-south of Europe, and decreased in the Amazonia of South America and the southeastern Asia. The NPP and RA showed similar spatial pattern as GPP did. The average changes of GPP, NPP, NEP, RA, RH and Reco in 2007 were +6.47 g C·m-2 (+1.13%), +2.23 g C· m-2 (+0.98%), +0.34 g C·m-2 (+4.04%), +4.24 gC m-2 (+1.25%), +1.89 g C·m-2 (+0.86%), +6.13 g C·m-2 (+1.13%), respectively. Simulations of canopy photosynthesis found that the photosynthetic carbon sequestration by sunlit and shaded leaves was also impacted by aerosols. The photosynthetic carbon sequestration by shaded leaves exhibited similar trend as GPP did, and its global average increased by 23.93 g C·m-2. The carbon sequestration by sunlit leaves decreased by a global average of -17.47 g C·m-2. Examinations of the carbon fluxes show that the aerosol direct radiative effects influence the carbon cycle in terrestrial ecosystem via the following two ways: first, the diffuse fertilization effect, i.e. more diffuse radiation being absorbed by shaded leaves of vegetation (photosynthetic active radiation, PAR) results in higher photosynthetic rates; second, the radiation changes lead to changes in temperature and humidity, thereby changing the rates of the plant biophysical and chemical processes.

Key words: aerosol, carbon cycle, diffuse fertilization, direct radiative effect, terrestrial ecosystem

CLC Number: 

  • X513