Chin J Plan Ecolo ›› 2017, Vol. 41 ›› Issue (11): 1177-1189.DOI: 10.17521/cjpe.2017.0098

• Research Articles • Previous Articles     Next Articles

Effects of biochar addition on dynamics of soil respiration and temperature sensitivity in a Phyllostachys edulis forest

Xiao-Gai GE1,2, Ben-Zhi ZHOU1,2,*(), Wen-Fa XIAO3, Xiao-Ming WANG1,2, Yong-Hui CAO1,2, Ming YE4   

  1. 1Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China

    2Qianjiangyuan Forest Ecosystem Research Station, State Forestry Administration, Hangzhou 311400, China

    3State Forestry Administration Key Laboratory of Forest Ecology and Environment;Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China

    4Shouchang Forest Center of Jiande, Shouchang, Zhejiang 311600, China
  • Received:2017-04-10 Accepted:2017-08-29 Online:2017-11-10 Published:2017-11-10
  • Contact: Ben-Zhi ZHOU

Abstract:

Aims Recent studies have shown that artificial addition of biochar is an effective way to mitigate atmospheric carbon dioxide concentrations. However, it is still unclear how biochar addition influences soil respiration in Phyllostachys edulis forests of subtropical China. Our objectives were to examine the effects of biochar addition on the dynamics of soil respiration, soil temperature, soil moisture, and the cumulative soil carbon emission, and to determine the relationships of soil respiration with soil temperature and moisture.
Methods We conducted a two-year biochar addition experiment in a subtropical P. edulis forest from 2014.05 to 2016.04. The study site is located in the Miaoshanwu Nature Reserve in Fuyang district of Hangzhou, Zhejiang Province, in southern China. The biochar addition treatments included: control (CK, no biochar addition), low rate of biochar addition (LB, 5 t·hm-2), medium rate of biochar addition (MB, 10 t·hm-2), and high rate of biochar addition (HB, 20 t·hm-2). Soil respiration was measured by using a LI-8100 soil CO2 efflux system.
Important findings Soil respiration was significantly reduced by biochar addition, and exhibited an apparent seasonal pattern, with the maximum occurring in June or July (except LB in one of the replicated stand) and the minimum in January or February. There were significant differences in soil respiration between the CK and the treatments. Annual mean soil respiration rate in the CK, LB, MB and HB were 3.32, 2.66, 3.04 and 3.24 μmol·m-2·s-1, respectively. Compared with CK, soil respiration rate was 2.33%-54.72% lower in the LB, 1.28%-44.21% lower in the MB, and 0.09%-39.22% lower in the HB. The soil moisture content was increased by 0.97%-75.58% in LB, 0.87%-48.18% in MB, and 0.68%-74.73% in HB, respectively, compared with CK. Soil respiration exhibited a significant exponential relationship with soil temperature and a significant linear relationship with combination of soil temperature and moisture at the depth of 5 cm; no significant relationship was found between soil respiration and soil moisture alone. The temperature sensitivity (Q10) value was reduced in LB and HB. Annual accumulative soil carbon emission in the LB, MB and HB was reduced by 7.98%-35.09%, 1.48%-20.63%, and -4.71%-7.68%, respectively. Biochar addition significantly reduced soil carbon emission and soil temperature sensitivity, highlighting its role in mitigating climate change.

Key words: biochar addition, soil respiration, Phyllostachys edulis, temperature sensitivity, soil temperature, soil moisture