Seasonal and long-term effects of nutrient additions and liming on the nifH gene in cerrado soils under native vegetation

iScience

Thiago de Roure Bandeira de Mello¹  Rafaella Silveira²  Mercedes Maria da Cunha Bustamante²  Carla Simone Vizzotto²  Ricardo Henrique Krüger²  Fernando Campos de Assis Fonseca²  Maria Regina Silveira Sartori³  Gabriel Sérgio Costa Alves³ 

[1]Corresponding author

[2]Cell Biology Department, Institute of Biology, University of Brasília, Brasília, DF 70910-900, Brazil

[3]Department of Ecology, Institute of Biology, University of Brasília, Brasília, DF 70910-900, Brazil

关键词: Microbiology;    Plant Ecology;    Global Nutrient Cycle;   

DOI  :  

来源: DOAJ

【 摘 要 】

Summary: Biological nitrogen fixation (BNF) represents the main input source of N in tropical savannas. BNF could be particularly important for Brazilian savannas (known as Cerrado) that show a highly conservative N cycle. We evaluated the effects of seasonal precipitation and nutrient additions on the nifH gene abundance in soils from a long-term fertilization experiment in a Cerrado's native area. The experiment consists of five treatments: (1) control, (2) liming, (3) nitrogen (N), (4) nitrogen + phosphorus (NP), and (5) phosphorus (P) additions. The nifH gene sequence was related to Bradyrhizobium members. Seasonal effects on N-fixing potential were observed by a decrease in the nifH relative abundance from rainy to dry season in control, N, and NP treatments. A significant reduction in nifH abundance was found in the liming treatment in both seasons. The findings evidenced the multiple factors controlling the potential N-fixing by free-living diazotrophs in these nutrient-limited and seasonally dry ecosystems.

【 授权许可】

Unknown