Autoria: PIMENTEL, M. L.; TENELLI, S.; ANDRADE, N.; NASCIMENTO, A. F. do; CARVALHO, J. L. N.; CHERUBIN, M. R.; BORDONAL, R. O.

Resumo: Abstract: Brazil’s agricultural expansion can lead to changes in activity of soil microorganisms, thus affecting soil conservation and carbon (C) sequestration in the Amazon biome. This study aimed to explore the interactions among glomalin-related protein, soil aggregation, and C accrual in anthropized soils under long-term adoption of different land use systems in southern Amazon, Brazil. A field experiment was conducted in a randomized block design with four replications and four treatments: Crop succession (CS) - annual production of soybean (Glycine max L.) followed by corn (Zea mays); Integrated crop-livestock system (ICL) - a rotation system of four years with soybean/corn production in the first year, soybean/corn + brachiaria (Brachiaria brizantha cv. Marandu) in the second year, followed by two years of pasture associated with cattle production; Pasture (MP) – continuous cultivation of brachiaria with cattle production; and Integrated crop-livestock-forest system (ICLF) – similar to ICL system, with the eucalyptus as additional forest component. Soil samples were collected to a 0.3 m depth, and the total C and glomalin-related soil protein (GRSP) contents and the soil structural quality from the mean weight diameter (MWD) of aggregates were analyzed. The data were submitted to analysis of variance, and the treatments means were compared using the Tukey test (p<0.05). Regression analyses were performed to understand the relationship between GRSP and MWD. Our findings revealed that MP increased C by 26%, GRSP by 21% and MWD by 10% as compared to CS. Regression analyses indicated that enhanced MWD was triggered by the increase in GRSP and soil C, especially in MP and ICL, indicating improved soil aggregation in these systems. This study suggests that ICL and MP systems play a crucial role in enhancing microbial activity, soil C, and soil aggregation.

Ano de publicação: 2024

Tipo de publicação: Resumo em anais e proceedings

Unidade: Embrapa Agrossilvipastoril

Palavras-chave: Carbono, Conservação do Solo, Uso da Terra