Micromorfologia de solo em diferentes sistemas de manejo: avaliação preliminar da aplicação da microscopia de varredura

Abstract

Agriculture, driven by technological advancements, has spurred in-depth investigations into soil properties. The No-Tillage System (NTS) emerges as a viable alternative for sustainable land use, with Scanning Electron Microscopy (SEM) providing valuable insights into its efficiency. This study aims to identify soil constituents and analyze porosity relationships under different management practices, including no-tillage and conventional tillage, using SEM. The experimental design follows a randomized complete block arrangement in a factorial scheme (12 x 2) with three replications and split plots. Winter cover crop species constitute the main plots (20 x 12 m), while soil preparation systems form the subplots (6 x 20 m). Treatments include cover crop mixes: hairy vetch + emerald oat with and without an autumn mix, and lupin + hairy vetch + emerald oat + triticale with and without an autumn mix. Additional treatments involve a clean fallow system (manual weeding) and a native forest soil used as a reference. Undisturbed soil samples were collected from each plot at depths of 0–5, 5–10, 10–20, and 20–40 cm after managing the cover crops with a knife roller. These samples were homogenized, and two composite depth ranges (0–20 cm and 20–40 cm) were defined for SEM observation. After preparing the soil samples for SEM, images were analyzed electronically using machine learning-based classification and examined at magnifications of 50x, 100x, 500x, and 1000x. Results confirm that native forest soil serves as the gold standard for structural quality, while fallow soil, particularly under conventional tillage at 20–40 cm, exhibits the poorest structural quality. The proposed methodology effectively classified and differentiated soil management systems, contributing to strategies for sustainable soil management.