ESTIMATES OF THE LEAF AREA INDEX (LAI) USING LAI-2000 AND HEMISPHERICAL PHOTOS IN Eucalyptus PLANTATIONS

The objective of this study was to estimate the Leaf Area Index (LAI) by indirect methods in plantations of Eucalyptus clones in two distinct physical-climatic sites, during the dry and rainy periods. The study was performed in four young and adult Eucalyptus stands, located in Rio Doce basin, eastern Minas Gerais state (Brazil) situated in areas of lower and higher altitudes. Nine plots were allocated in each stand. Experimental data were collected in months representing the driest and the wettest periods. LAI indirect measurements were performed using the LAI-2000 equipment and cameras with hemispherical lens. To verify the accuracy of estimation, a destructive analysis was also performed. The LAI measurements by the LAI-2000 was the one which best correlated with the observed LAI (R =0.90), although the hemispherical photos had presented good potential use. It is verified that the LAI of stands in the higher altitudes region, surpassed those of lower altitudes, which was also observed by the indirect methods. The destructive analysis indicates lower values of LAI measured in the dry season although this variation is only significant for higher altitudes. This behavior is also observed for estimates with the LAI-2000, different from the hemispherical photographs which did not identify seasonality of LAI.