Advanced search
Start date

Long-term land use in Amazon influence the dynamic of microbial communities in soil and rhizosphere

Full text
Merloti, Luis Fernando ; Pedrinho, Alexandre ; Mendes, Lucas William ; Gontijo, Julia Brandao ; da Fonseca, Mariley de Cassia ; Chaves, Miriam Goncalves ; Chaves, Siglea Sanna de Freitas ; de Camargo, Plinio Barbosa ; Tsai, Siu Mui
Total Authors: 9
Document type: Journal article
Source: RHIZOSPHERE; v. 21, p. 14-pg., 2022-03-01.

Brazil has become the world leader in soy production, leading to an increase in the conversion of the Amazon rainforest into cropland. These actions had consequences for Forest's biodiversity, including the soil. In this sense, a better understanding of how long-term land use affects soil microbial communities, and their functions is urgent. This study aimed to evaluate the long-term land-use effects over bacterial and archaeal communities in soil and soybean rhizosphere in the Amazon region. For this, mesocosms experiments were carried out with Amazon soils with a history of 2-, 8-, and 20-years of agricultural use. We then assessed the bacterial and archaeal communities based on the 16S rRNA sequencing and real-time PCR. Our results showed a distinct bacterial community structure in soils with 20-years of land use. For both, bulk soil and soybean rhizosphere with 20-years of use, there was an increase in the abundance of Gemmatimonadetes, Chloroflexi, Firmicutes, and Planctomycetes. Interestingly, the niche occupancy analysis revealed an increase of specialist microbes in these soils. Also, these soils with 20-years of use showed a more complex network for both bulk and rhizosphere samples, highlighting the importance of Actinobacteria and Chloroflexi phyla to soil network structure. Our analysis also revealed an increased abundance of total bacteria, N-fixers, and ammonia-oxidizers bacteria in rhizosphere soil with 20-years of use. In addition, based on the potential functional analysis, nitrification processes increased in those soils. However, we noticed a homogenization in the abundance of the genes between rhizosphere and bulk soil with 20-years of use. In general, the differences were associated with changes in soil chemical characteristics such as pH, Ca2+, Mg2+, and organic matter, which are a consequence of liming and no till practices over time. Our findings demonstrate that long-term agriculture in Amazon soils affects microbial community composition and functions, bringing new insights to better understand anthropogenic actions over the soil microbiome. (AU)

FAPESP's process: 20/12890-4 - Rhizosphere microbiome of the drought tolerant common bean
Grantee:Lucas William Mendes
Support Opportunities: Scholarships in Brazil - Research Program on Global Climate Change - Young Investigators
FAPESP's process: 14/50320-4 - Dimensions US-BIOTA - São Paulo: collaborative research: integrating dimensions of microbial biodiversity across land use change in tropical forests
Grantee:Tsai Siu Mui
Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
FAPESP's process: 19/19145-5 - Ammonium-oxidizers dynamic in Atlantic Forest soils: impact of forest-to-pasture conversion and nitrogen fertilization
Grantee:Luis Fernando Merloti
Support Opportunities: Scholarships in Brazil - Doctorate