Produção e avaliação da qualidade de composto orgânico à base de esterco ovino e seu uso no cultivo de estacas da planta ornamental Costela-de-Eva (Monstera adansonii)

Abstract

The relevance of this research lies in the pursuit of more sustainable and efficient agricultural practices, using organic waste from sheep farming to promote the healthy development of an ornamental plant used in landscaping—a sector that has been steadily growing, as has sheep farming. The main objective was to reuse waste generated by sheep farming activities through composting, evaluating the quality of the resulting compost and testing its effectiveness in the cultivation of cuttings of the plant Costela-de-Eva (Monstera adansonii, Schott, 1830). The methodological procedures adopted in the research involved four main stages. In the first stage, a literature review was conducted to gather information related to the topic. The second stage consisted of the composting process of two piles (compost 1 and compost 2), which began with the collection of waste, selection of an appropriate location, assembly of the compost piles, and monitoring of the composting process. In the third stage, the quality of the produced composts was assessed and compared with reference samples (commercial substrate and raw sheep farming waste) through laboratory analyses that quantified nutrient contents such as calcium, magnesium, aluminum, nitrogen, phosphorus, potassium, and carbon. Additional analyses included pH, organic matter, water retention capacity, electrical conductivity, and moisture. Furthermore, as part of the quality assessment, a respirometry test was carried out by measuring CO₂ and NH₃ emissions to evaluate sample stability. In the fourth stage, the cultivation of M. adansonii cuttings was evaluated using different proportions of the produced compost (CO), sand (AR), and commercial substrate (SC). The experimental design was a randomized block design, consisting of 9 treatments with 10 replications, totaling 90 plots, with one cutting per plot: T1 (100% AR); T2 (75% AR + 25% CO); T3 (50% AR + 50% CO); T4 (25% AR + 75% CO); T5 (100% CO); T6 (75% AR + 25% SC); T7 (50% AR + 50% SC); T8 (25% AR + 75% SC); T9 (100% SC). The following criteria were evaluated: survival, growth, root dry mass, leaf area, number of leaves, and time to emergence of the first leaf. Descriptive statistical analyses were conducted, as well as additional analyses in RStudio with a significance level of 5% (α = 0.05). The results showed that organic compost 1 surpassed the commercial substrate in potassium, magnesium, organic matter, and organic carbon, while organic compost 2 surpassed it in potassium, organic matter, and organic carbon. Both organic composts presented low CO₂ and NH₃ emissions in the respirometry test, indicating the importance of the composting process for organic matter stability. In the cultivation of M. adansonii, treatments T3, T4, and T5 stood out in growth, root dry mass, leaf area, number of leaves, and time to emergence of the first leaf, demonstrating the viability of using organic compost based on sheep manure as a substrate.