Establishment of recommendation domains for the fertilization of Arabica coffee plantations in the province of Manabí, Ecuador

Abstract Aims To determine the nutrient contents, organic matter, and acidity levels in soil samples from various coffee-growing localities in the province of Manabí, Ecuador, and to identify the critical chemical elements that allow for the differentiation of Arabica coffee soils to determine recommendation domains according to similarities of these soils. Methods A total of 251 soil samples were analyzed, taken from producing coffee plantations in seven cantons and 16 parishes of the province. The factors studied were: acidity level (pH), organic matter (%), and nutrient contents. The chemical variables were: pH, organic matter, N, P, K, Ca, Mg, S, Fe, Cu, Mn, Zn, and B. Using acidity level as the primary classification criterion and multivariate statistical methods, the coffee plantations were grouped. Results Deficiencies in nitrogen, sulfur, zinc, and boron prevail in most of the farms studied, and farms were grouped on these bases and the acidity of soils, according with the recommended for coffee plantations. From these groupings, seven recommendation domains were established for the fertilization of coffee plantations. Conclusions These criteria can be applied to the implementation of orderly and fair fertilization plans, which would help achieve more efficient fertilizer management based on the actual needs of the plantations, causing less harm to the environment.