Title : Soil quality in different agroecosystems: A chromatographic analysis
Abstract:
This study investigated soil health and quality in different agroecosystems within the Rio Seco Agroecology Center (CEARIS), located in the municipality of Amélia Rodrigues, Bahia. The main objective was to analyze how agroecological management influences soil vitality, using a comparative approach that integrates conventional scientific methods and agroecological techniques. The methodology involved soil sampling in three areas: secondary forest, an Agroforestry System (AFS), and a fallow area. The samples were subjected to laboratory chemical analysis and Pfeiffer Chromatography. For the chromatographic technique, the soil was solubilized in a caustic soda solution (1% NaOH), followed by the impregnation of a circular filter paper previously sensitized with silver nitrate (0.5% AgNO3). The capillary rise of the soil solution on the paper allowed the development of color patterns and radial zones (central, inner, intermediate, and outer), reflecting the integration of minerals, organic matter, and microbiological activity. The comparison between the two analyses was fundamental to this study, as laboratory analysis provides quantitative data on the isolated availability of nutrients, while chromatography reveals the biological quality and the level of organization of these elements within the ecosystem. This comparative approach enables a comprehensive reading of soil fertility, linking laboratory data to real vitality and the dynamism of biological processes observed in the field. The synthesis of the results reveals a strong connection between the two techniques. While laboratory analysis quantified high levels of phosphorus (P) and potassium (K) in the AFS compared to the other areas, Pfeiffer Chromatography made it possible to visualize the integration of these minerals with organic matter and microbial activity. The chromatograms of the AFS showed well-defined radial zones and vibrant colors, indicating a biologically active soil undergoing regeneration. In contrast, the fallow area and the forest, although exhibiting good structural characteristics, showed chromatographic patterns suggesting lower immediate nutrient availability or reduced mineral integration, thereby validating the numerical laboratory data. Finally, the study highlights the importance of chromatography as a technique of peasant biopower. As a visual, low-cost, and practical method, it democratizes access to technical information. This tool makes soil diagnosis accessible and understandable for family farmers, restoring their autonomy over land management and strengthening technological sovereignty in rural areas.
