Método para definir e calcular área de influência amostral em mapeamento de cafezal (Coffea arabica L.) de montanha em Viçosa, MG.

Abstract

A problem to map agricultural crop, mainly of cultures with irregular spacing, it is to define and to calculate the cells area of the crop mesh. A method was proposed to define and to calculate the sample area of influence (AIA) for coffee plantation mapping in a mountainous region of Viçosa, MG, Brazil, during the 2002/3 harvest. The studied area consisted of about one ha and it was cultivated with Coffea arabica L. cv. Catuaí Vermelho in a 1 x 2.5 m spacing and it was not irrigated. The coffee trees had age between 5 and 12 years and height between 0.5 and 4 m. The method consisted of three phases. In the phase before crop the area was divided in sections. An outline polygon for that area and one coffee tree for each section were referenced with DGPS. The GPS carrier signal was tracked and post-processed with differential correction. Each referenced coffee tree was codified and labeled with an alphanumeric code. In the harvest phase the position of bags was identified with this code. In the phase after harvest the referenced coffee trees were mapped. An AIA was defined for each bag and two average distances between lines and the AIAs were calculated. The proposed method considered part of the spacing variation and part of the crop mesh regularity along the area, and displays that Agriculture of Precision can be applied in mountainous area.