Dr Amanda Tadini1, Dr. Ladislau Martin-Neto1, Dr. Débora M.B.P. Milori1, Dr. Alberto C. C. Bernardi2
1Embrapa Instrumentação, São Carlos, SP, Brazil, São Carlos, Brazil, 2Embrapa Pecuária Sudeste, São Carlos, SP, Brazil, São Carlos, Brasil
The current challenge in Brazilian agriculture is to maintain and advance the productive capacity of soils by using green technologies that are capable of promoting the sustainable growth of agricultural production. Soil organic matter (SOM) plays an important role in environmental sustainability and it is a central component in the Brazilian Low Carbon Agriculture Plan. This plan has seven main eligible agricultural practices including adoption of Integrated Crop-Livestock-Forest Systems (ICLF). In this study were compared data from ICLF and native forest areas from a dystrophic Red-Yellow Latosol (Oxisol) in an experimental field of Embrapa, in São Paulo State, Brazil. After 5 years of experiment soil carbon content was determined by CHN analysis, and structural aspects analysis of SOM performed, as humification degree, detected by Laser Induced Fluorescence Spectroscopy (LIFS) with whole soil samples measurements, and aromaticity degree of soil humic acids obtained by 13C Nuclear Magnetic Resonance (NMR) analysis. An increase of around 20% in soil C content in ICLF comparatively to native forest areas was determined, indicating soil carbon sequestration. SOM humification degree, determined by LIFS, from whole soil samples indicated an increase with soil depth (until 1m) and higher values in areas under ICLF comparatively to native forest. Aromaticity degree measurements of humic acids, determined by 13C NMR, indicated similar pattern results obtained with SOM humification degree, detected by LIFS, with the Pearson correlation R= 0.86, showing consistent SOM structural aspects. So current field experiment aligned with spectroscopic analysis permitted to identify soil carbon sequestration in ICLF areas, with relatively higher organic matter chemical stability, compared to native forest areas. These are additional evidences that ICLF in tropical regions is an agricultural sustainable intensification practice.