Abstract
In the context of global efforts to reduce carbon (C) emissions, several studies have examined the effects of agricultural practices such as straw returning and fertilization on C sequestration by microorganisms. However, our understanding of the specific microbial groups and their roles in long-term C increase remains limited. In this study, a 36-year (1984–2020) farmland experiment was conducted to investigate the impact of bacterial C metabolism on the augmentation of organic C in a Typic Hapludoll (Mollisol) in the black soil region of Jilin Province, Northeast China. Our results demonstrated a noteworthy increase in the diversity of microorganisms in the farmland as a result of long-term straw returning and application of mixed chemical fertilizers. However, by examining the functions of microorganisms involved in C metabolism, it was observed that the effects of fertilization on C metabolism were relatively consistent. This consistency was attributed to a deterministic competitive exclusion process, which minimized the differences between treatment groups. On the other hand, the influence of straw addition on C metabolism appeared to follow a more random pattern. These changes in microbial activity were closely linked to the downregulation of core metabolic pathways related to C metabolism. Notably, long-term fertilization had a negative impact on soil organic C levels, while long-term straw returning plus fertilization resulted in a positive increase in soil organic C. These findings have important implications for enhancing soil organic C and grain yield in the regions with typical black soil.
Original language | English |
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Pages (from-to) | 853-864 |
Number of pages | 12 |
Journal | Pedosphere |
Volume | 34 |
Issue number | 5 |
Early online date | 26 Sept 2024 |
DOIs | |
Publication status | Published - Oct 2024 |
Keywords
- community assembly
- metabolic pathway
- microbial activity
- Mollisol
- soil organic C
- straw addition