Estimating of the Volume of Eucalyptus with Kriging and Cokriging in Semi-arid of Pernambuco

ABSTRACT The volumes of 1875 eucalyptus plantation trees were strictly cubed by Smalian process, thus knowing the total volume of planting of 166.14 m3, the trees were located on a plane (X, Y) and two geostatistical techniques were applied, kriging and cokriging. For cokriging was used as the secondary variable (DBH) diameter at breast height of the entire population, variable with high correlation with the volume of Eucalyptus wood. Three sizes of samples were taken - 200, 100 and 50 - and the estimates of the volumes were performed for each sample using both geostatistical techniques. The sample size did not affect the estimates of the total volume of planting. The cokriging provided better results than kriging for the smaller samples. The maps of spatial distribution volume were constructed.