Under field condition, soil respiration consists of heterotrophic respiration from soil microbe and autotrophic respiration from plants. Temperature sensitivity (Q10) is a common method for describing proportional changes in soil heterotrophic respiration in response to warming. However, it remains unclear how the available substrate and the soil microbial community regulate the Q10 of soil microbial respiration under natural warming conditions.
In a study published in Science of The Total Environment, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) and Anhui Academy of Agricultural Sciences presented the first study focusing on the community thermal adaptation to the Q10 of soil respiration based on the niche breadth of the microbial community composition.
The researchers conducted a long-term field experiment consisting of two years of soil respiration observations, combined with a soil available substrate and microbial community thermal adaptation analysis under seasonal warming conditions.
They firstly analyzed the contribution of microbial properties and soil water content, NH4-N, NO3-N, dissolved organic carbon (DOC), and dissolved organic nitrogen (DON), temperature to soil respiration. They found that soil respiration under changing temperature was mainly caused by soil microbe and soil available substrate variation.
They also analyzed the contributions of soil water content, temperature, DON, DOC, NH4-N and NO3-N to bacterial and fungal community structure to characterize the community thermal adaptation as temperature changing under field condition. They found that temperature was the primary factor in structuring soil bacterial and fungal community.
The results indicated that the available substrate contributed more to regulating the Q10 of soil heterotrophic respiration than microbial community thermal adaptation. Fertilization management had a stronger effect on soil available substrate than temperature.
"We can say that changing available nitrogen and DOC primarily caused by fertilization management contributed more in regulating the Q10 of soil microbial respiration than microbial community thermal adaptation,” said LIU Changan of XTBG.
Contact
LIU Changan Ph.D
Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun 666303, Yunnan, China
E-mail: liuchangan@xtbg.ac.cn
First published: 6 December, 2023
