Soil quality in the black oat and soybean succession system irrigated with treated slaughterhouse effluent

• Autor(a) principal: Brichi, Lisiane
• Data de Publicação: 2023
• Tipo de documento: Tese
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: https://www.teses.usp.br/teses/disponiveis/11/11152/tde-05022024-170735/
• topic: Crop succession; Indicadores; Indicators; Reúso de água; Saúde do solo; Soil health; Sucessão de culturas; Water reuse

The increasing demand for food has led to the search for alternatives that do not generate environmental pressure and align with sustainable agricultural practices. In this context, the reuse of treated slaughterhouse effluent (TSE) emerges as an environmentally and economically viable, as well as socially responsible strategy. Additionally, it presents an excellent option for the restoration of soil health due to its high nutrient content and organic matter. Thus, the objectives of this thesis were to map, through bibliometric evaluations, how this research topic has been assessed in recent years and the relevance of the subject (Chapter 1), as well as to evaluate the impacts of this type of effluent on a crop succession system (black oats/soybean) concerning soil quality/health aspects (Chapters 2, 3, and 4). To accomplish this, the experiment was designed in randomized blocks, with five treatments and four replications, namely: T1 - 0%, T2 - 100%, T3 - 75%, T4 - 50%, and T5 - 25% of the recommended nitrogen (N) doses for crops through TSE irrigation. In treatment T1 - 0%TSE, the required N doses were supplied using nitrogen fertilizer in the form of urea, through sprinkler irrigation. For the comparison of soil quality indicators, a sixth treatment, T6 - NV, was studied, corresponding to an area of native vegetation (seasonal semideciduous forest). The results from the first chapter demonstrate that although not extensively studied, TSE can positively impact soil chemical quality, and other indicators related to soil physical and biological quality require further investigation. Meanwhile, the results from Chapters 2 and 3 showed that the 75% TSE dose (T3) appears suitable concerning soil physical and chemical quality. However, in Chapter 4, there was no evidence that different doses of TSE impacted the soil quality indices studied. It is essential to highlight that the application of TSE was not detrimental to soil quality, indicating the potential for effluent reuse. It is hoped that this study will inspire future research to conduct more measures like this one, directly aligned with the concept of a circular economy.