Geostatistical estimator for forest yield prediction at stand level.

Abstract

The estimate wood volumetric per stand, in forest plantation, is made through the before felling inventory. For accomplishing the inventory a larger number of plots is established in the stand. Therefore, besides the cost of measuring the plots of the Continuous Forest Inventory, it is added the cost of the before felling forest inventory. The analysis of the information of the before felling inventory is made using classic statistics concepts, not considering the spatial continuity structure. One way of getting the volumetric information per stand would be to use a method of estimating the volume per stand using the information of the Continuous Forestry Inventory. Block Krigage is a geostatistic prediction method capable of predicting volume per stand. This method predicts the volume, considering the hole forest population spatial continuity to which the stands belong. This research compared the estimates made by stand using classic estimators and geoestatístic estimators. Data were collected in five Eucalyptus grandis stands, belonging Votorantim Pulp and Paper. Total volume with bark of the fixed plots and the information of the before felling inventory were obtained. The statistics of the before felling inventory and those of the geoestatístic estimator were compared. The average difference among the total volume, generated by the classic estimator and the geostatístic estimator was 1%. The sampling error, per stand, of the geostatístic estimator varied less than that of the classic estimator. The use of the geoestatístic estimator for volume estimates, per stand, is recommended, because it cost less and is more precise than the classical before felling forestry inventory.