versão On-line ISSN 1809-4430
OLIVEIRA, Rone B. de et al. Comparison between soil sampling methods for conilon coffee liming and fertilization recommendation. Eng. Agríc. [online]. 2008, vol.28, n.1, pp. 176-186. ISSN 1809-4430. http://dx.doi.org/10.1590/S0100-69162008000100018.
This study aimed to evaluate the soil sampling conventional methodology with spatial analysis for liming and fertilization with nitrogen, phosphorus and potassium on soil cultivated with conilon coffee. The trial was carried out during the 2004/2005 - 2005/2006 harvests in a 1.0 ha area with samples collected at 0-0.20 m depth. Fifteen sub samples in zigzag were collected for the conventional method forming a compound sample; as for the spatial method, 109 georeferenced points formed a sample grid. After the analysis results, the liming and fertilization needs were calculated based on the function of the element content in the soil and on the plant expected yield. Data were analyzed by both the classical statistics (descriptive and exploratory) and spatial analysis, using geostatistics techniques (modeling of the spatial variability structure and inferences) and geoprocessing (map algebra). Except for phosphorus in 2005 and potassium in 2006, every other recommendation showed spatial dependence. Data analysis by the spatial method provided the identification of zones with deficient or excessive liming and fertilization which could not be defined by the conventional sampling method (zigzag).
Palavras-chave : geostatistics; geoprocessing; soil management.