TY  - EJOU
AU  - Lu, Weiwei 
AU  - Zhang, Yirui 
AU  - Yao, Yixian 
AU  - Wu, Yuying 
AU  - Chen, Han Y. H. 
AU  - Zhang, Hailin 
AU  - Yu, Jia 
AU  - Shen, Caiqin 
AU  - Liu, Qi 
AU  - Ruan, Honghua 

TI  - Biochar-Induced Priming Effects in Young and Old Poplar Plantation Soils
T2  - Phyton-International Journal of Experimental Botany

PY  - 2020
VL  - 89
IS  - 1
SN  - 1851-5657

AB  - The priming effect (PE) induced by biochar provides a basis for 
evaluating its carbon (C) sequestration potential in soils. A 60 days’ laboratory 
incubation was conducted, which involved the amendment of biochar (1% of soil 
mass) produced from rice straw at 300ºC (B300) and 500ºC (B500) to young (Y) 
and old (O) poplar plantation soils, with the aim of studying the responses of 
biochar-induced PEs to poplar plantation ages. This incubation included six 
treatments: Y + CK (control), Y + B300, Y + B500, O + CK, O + B300, and O +
B500. Carbon dioxide (CO<sub>2</sub>) emissions were significantly increased (<i>p</i> < 0.05) in 
the B300 amended soils, while it was decreased in the B500 amended soils 
compared to the CK. The primed CO<sub>2</sub> emissions were 2.35 times higher in the Y
+ B300 than the O + B300 treatments, which was measured to be 18.6 and 5.56 
mg C·kg<sup>-1</sup> with relative PEs of 12.4% and 3.35%, respectively. However, there 
was little difference between the primed CO2 emissions in Y + B500 and O +
B500 treatments, which were measured to be -24.9 and -29.6 mg·C·kg<sup>-1</sup> with 
relative PEs of -16.6% and -17.8%, respectively. Dissolved organic carbon 
(DOC) was significantly lower in the young poplar plantation soil than that in the 
old poplar plantation soil regardless of biochar amendment throughout the 
incubation, indicating greater C-limit of soil microorganisms in the young poplar 
plantation soil. Using <sup>13</sup>C isotope tracing, neither B300 nor B500 decreased 
native soil-derived DOC, which indicated that the negative B500-induced PEs 
were not due to a reduction in the availability of native soil-derived C. In 
conclusion, the response of biochar-induced PEs to poplar plantation age 
depends on biochar types while soil available C indirectly affects biocharinduced PEs. Further studies should focus on how the interactive effects between 
soil C availability and microbial community impacts biochar-induced PEs.
KW  - Biochar; dissolved organic carbon; pyrolysis temperature; poplar  plantation age; priming effect

DO  - 10.32604/phyton.2020.09125