VARIABILIDADE ESPACIAL DA CAPACIDADE DE CAMPO E PONTO DE MURCHA PERMANENTE EM ARGILOSO AMARELO COESO

Abstract

The knowledge of the spatial variability of field capacity and permanent wilting point is important for decision making in the management of irrigation, in order to meet properly the crop water requirement. The objective of this study was to evaluate the spatial variability of field capacity and permanent wilting point in a Cohesive Yellow Argisol cultivated with Conilon coffee in Norte Capixaba. For reviews of field capacity (CC) and permanent wilting point (PMP), undisturbed soil samples were taken on the line and leading culture, with four points, equidistant in relation to the culture (0, 50, 100 and 150 cm) five depths 0-20, 20-40, 40-60, 60-80 and 80-100 cm, with four replications. All samples were tensions of 10 to 1500 kPa, a CC and PMP, respectively. The results were submitted to descriptive statistical analysis and spatial dependence was assessed by variograms settings. For all events, the mean and median value is presented, close to each other, showing symmetrical distribution, which can be confirmed by the skewness coefficient zero and near zero kurtosis. The spatial dependence index for CC and PMP was strong for all models, but the Gaussian was the best set. The spatial dependence was strong for CC and PMP, with a range of 240 cm (CC) and 250 cm (PMP). The field capacity and the permanent wilting point showed a moderate spatial variability can be interpolated through kriging methods with very small errors.