Stoichiometric regulation of priming effects and soil carbon balance by microbial life strategies

Carbon and nutrient inputs are required to stimulate the formation and mineralization of soil organic carbon (SOC) through processes related to microbial growth and priming effects (PEs). PEs are thought to affect microbial life strategies, however, the mechanisms underlying their role in SOC formation and microbial dynamics remain largely unknown, particularly in paddy soils. Here, we examined the underlying strategies and response mechanisms of microorganisms in regulating PEs and C accumulation in flooded paddy soil. Levels and stoichiometric ratios of resources were evaluated over a 60-day incubation period. Low (equivalent to 50% soil microbial biomass C [MBC]) and high (500% MBC) doses of 13C-labeled glucose were added to the soil, along with mineral N, P, and S (NPS) fertilizers at five concentrations. Glucose mineralization increased linearly with NPS concentration under both low and high glucose inputs. However, glucose addition without nutrients induced the preferential microbial utilization of the readily available C, leading to negative PEs. Under high-glucose input, the intensity of negative PEs increased with increasing NPS addition (PE: from −460 to −710 mg C kg−1 soil). In contrast, under low-glucose inputs, the intensity of positive PEs increased with increasing NPS addition (PE: 60–100 mg C kg−1 soil). High-glucose input with NPS fertilization favored high-yield microbial strategists (Y-strategists), increasing glucose-derived SOC accumulation. This phenomenon was evidenced by the large quantities of 13C detected in microbial biomass and phospholipid fatty acids (PLFAs), increasing the soil net C balance (from 0.76 to 1.2 g C kg−1). In contrast, low levels of glucose and NPS fertilization shifted the microbial community composition toward dominance of resource-acquisition strategists (A-strategists), increasing SOC mineralization. This was evidenced by 13C incorporation into the PLFAs of gram-positive bacteria, increased activity of N- and P-hydrolases, and positive PEs for acquiring C and nutrients from soil organic matter. Consequently, the soil net C balance decreased from 0.31 to 0.01 g C kg−1 soil. In conclusion, high C input (i.e., 500% MBC), particularly alongside low N:P:S ratios, increases SOC content via negative priming and microbial-derived C accumulation due to the shift toward Y-strategist communities which efficiently utilize resources. This study highlights the importance of mineral fertilization management when incorporating organic supplements in paddy soils to stimulate microbial turnover and C sequestration. © 2022 Elsevier Ltd

Авторы
Zhu Z.1, 2 , Fang Y.3 , Liang Y.1 , Li Y. 1, 4 , Liu S.1 , Li Y. 1, 4 , Li B.1 , Gao W.1 , Yuan H.1 , Kuzyakov Y. 2, 5, 6 , Wu J.1 , Richter A.7 , Ge T. 1, 2
Издательство
Elsevier Ltd
Язык
Английский
Статус
Опубликовано
Номер
108669
Том
169
Год
2022
Организации
  • 1 Changsha Research Station for Agricultural and Environmental Monitoring & Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan410125, China
  • 2 State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
  • 3 NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, MenangleNSW 2568, Australia
  • 4 State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China
  • 5 Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, University of Göttingen, Göttingen, 37077, Germany
  • 6 Peoples Friendship University of Russia (RUDN University), Moscow, 117198, Russian Federation
  • 7 Centre for Microbiology and Ecosystem Science, University of Vienna, ViennaA-1090, Austria
Ключевые слова
13C isotope; Microbial community composition; Microbial life strategy; Microbial phospholipid fatty acid; Nutrient stoichiometry; Soil organic carbon
Дата создания
06.07.2022
Дата изменения
06.07.2022
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/83596/
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