Soil temperature and biotic factors drive the seasonal variation of soil respiration in a maize (Zea mays L.) agricultural ecosystem |
| |
Authors: | Guangxuan Han Guangsheng Zhou Zhenzhu Xu Yang Yang Jingli Liu Kuiqiao Shi |
| |
Institution: | (1) Laboratory of Quantitative Vegetation Ecology, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, P.R. China;(2) Graduate School of the Chinese Academy of Sciences, Beijing, 100039, P.R. China;(3) Institute of Atmospheric Environment, China Meteorological Administration, Shenyang, 110016, P.R. China;(4) Meterological Bureau of Jinzhou, Jinzhou, 121001, P.R. China |
| |
Abstract: | The diurnal and seasonal variation of soil respiration (SR) and their driving environmental factors were studied in a maize
ecosystem during the growing season 2005. The diurnal variation of SR showed asymmetric patterns, with the minimum occurring
around early morning and the maximum around 13:00 h. SR fluctuated greatly during the growing season. The mean SR rate was
3.16 μmol CO2 m−2 s−1, with a maximum of 4.87 μmol CO2 m−2 s−1 on July 28 and a minimum of 1.32 μmol CO2 m−2 s−1 on May 4. During the diurnal variation of SR, there was a significant exponential relationship between SR and soil temperature
(T) at 10 cm depth:
. At a seasonal scale, the coefficient α and β fluctuated because the biomass (B) increased α, and the net primary productivity (NPP) of maize markedly increased β of the exponential equation. Based on this, we developed the equation
to estimate the magnitude of SR and to simulate its temporal variation during the growth season of maize. Most of the temporal
variability (93%) in SR could be explained by the variations in soil temperature, biomass and NPP of maize. This model clearly
demonstrated that soil temperature, biomass and NPP of maize combined to drive the seasonal variation of SR during the growing
season. However, only taking into account the influence of soil temperature on SR, an exponential equation over- or underestimated
the magnitude of SR and resulted in an erroneous representation of the seasonal variation in SR. Our results highlighted the
importance of biotic factors for the estimation of SR during the growing season. It is suggested that the models of SR on
agricultural sites should not only take into account the influence of soil temperature, but also incorporate biotic factors
as they affect SR during the growing season. |
| |
Keywords: | Biomass Net primary productivity Soil respiration Soil temperature Temporal variation |
本文献已被 SpringerLink 等数据库收录! |
|