Soil sampling optimization using spatial analysis in irrigated mango fields under brazilian semi-arid conditions

Abstract

Soil sampling is a fundamental procedure in the decision making regarding the management of the soil, thus, a sampling plan should represent as accurately as possible the evaluated crop field. Therefore, the objectives of this study were to suggest a soil sampling approach and soil sampling point allocation using spatial analyses and compare to the classic statistic method in irrigated mango orchards in the Brazilian semi-arid region. The experiment was carried out in three commercial mango orchards located in the region of the São Francisco Valley, Brazil. Soil samples were collected in 0-0.2 m and 0.2-0.4 m depths following regular grids where the number of samples varied from 50 to 56. Soil texture, soil bulk density, soil total porosity, microporosity, macroporosity, pH, Ca, Mg, Na, K, Al, P, potential acidity, and the sum of basis were evaluated. Classical and geostatistical statistics were used to determine the ideal number of soil samples. Fuzzy c-means clustering technique was used to separate the areas into homogeneous zones and to allocate the sampling points. The wide method of 20 individual soil samples proved to be inefficient. On the other hand, the use of geostatistics proved to be efficient and is required for each crop field. The c-means clustering was adequate to separate the areas into homogeneous zones and, thus, to assist the sampling point allocation.

Spatial correlation between soil and leaf macronutrients in semiarid Brazilian mango (Mangifera indica L.) fields

“…It also demonstrates that the spatial variability can be related to anthropomorphic factors such as fertilization and irrigation. Therefore, as stated by Silva et al (2020), a geostatistical analysis is required for each crop field to understand and quantify the spatial variability of its variables.…”

“…The delimitation of MZs using soil maps is a viable and efficient tool for optimizing fertilization in crop fields, as reported in several studies (AGGELOPOULOU et al, 2013;FAROOQUE et al, 2012;OLDONI et al, 2019;SILVA et al, 2020). However, most of these studies did not consider leaf analysis.…”

Vis-NIR-SWIR spectroscopy in mapping of soil physical-chemical attributes in areas cultivated with irrigated mango in the Brazilian semi-arid region

“…Proper management of fertilization and irrigation is essential to achieve high yield and quality of mango fruits (Faria et al, 2016 a;Faria et al, 2016 b), and for this it is necessary to have knowledge about the physical-chemical attributes of the soil. However, the Sub-middle São Francisco Valley region is characterized by the high spatial variability of soil physical-chemical attributes, even in small areas (smaller than 10 ha) (Rodrigues et al, 2015;Rodrigues et al, 2018;Silva et al, 2020). This makes it difficult to map the physical-chemical attributes of the soil, as it is necessary to increase sampling density, resulting in higher cost and longer time of analysis (Lu et al, 2013;Silva et al, 2020), in addition to the generation of waste (Cezar et al, 2019;Lima et al, 2019) that can harm the environment.…”

A difusão de tecnologias no meio agrícola na Caatinga – a região de clima semiárido brasileiro

“…A agricultura irrigada na Caatinga tem contribuído para o fortalecimento socioeconômico por meio de práticas agrícolas diversificadas, impulso à agroindústria e exportação de produtos em larga escala (LACERDA et al, 2021). Isso se tornou possível a partir da implementação de modernos sistemas de transporte de águas do rio São Francisco ou de reservatórios até as propriedades rurais (PEREIRA; CARMO, 2014), bem como pelo uso de alta tecnologia paralelamente associada à entrada de empresas agrícolas, agroquímicas, agroindustriais, atacadistas e varejistas (OLIVEIRA; RODRIGUES, 2020), fato este que transformou áreas "marginais" em "vales" ou regiões integradas de desenvolvimento agrícola, sendo esses os principais responsáveis por produzir e exportar frutas no Brasil (CARNEIRO et al, 2019;SILVA et al, 2020a). Todavia, o setor agrícola, mesmo na Caatinga, não se comporta de forma homogênea, pois esse exemplo de maior nível tecnológico se aplica a áreas restritas, em que, na maior parte do bioma, os produtores têm de conviver com condições geográficas, institucionais e estruturais distintas (SILVA et al, 2019).…”