LEAF AREA DETERMINATION IN POPULUS ALBA L. BY NON-DESTRUCTIVE METHOD BASED ON LEAF PARAMETERS. PUBLISHEDSimona ROȘU, F. SALA None email@example.com
The study aimed to determine the leaf area of poplar by non-destructive methods, based on foliar parameters. The biological material was represented by the Populus alba L. species, from the Protected Area Cenad Forest. Leaves were taken, randomly from the crown of trees, from mature branches. The values of the parameters leaf length (L) and leaf width (w) were obtained by measuring with a ruler, with an accuracy of ± 0.5mm. The leaves were scanned in a 1: 1 ratio. From the imaging analysis of the images, the values of the scanned leaf area (SLA) and the leaf perimeter (Per) were obtained with a high precision. To determine the values of the measured leaf area (MLA), as a non-destructive method, a relation of type MLA = L · w · CF was used, where CF is the correction factor and its value influences the accuracy in finding the MLA values. The ANOVA single factor test confirmed the data safety and the presence of variance in the experimental data set. The value CF = 0.66, at which the minimum value of the mean error (MEM) between SLA and MLA was obtained, was considered as the optimal value of the correction factor (CF). According the optimal CF value, the measured leaf area (MLA) values were determined. A high degree of matching was found between MLA and SLA values, and the relationship was described by a linear equation, statistically safe, according to R2=0.963, p<0.001. The correlation analysis highlighted the existence of very strong correlations between MLA and SLA (r = 0.981); between MLA and foliar parameters L (r = 0.919), w (r = 0.954), Per (r = 0.961); between SLA and Per (r = 0.952); between SLA and w (r = 0.951); between Per and w (r = 0.935). Strong correlations were recorded between SLA and L (r = 0.888) and between Per and L (r = 0.882), and moderate correlation was recorded between L and w (r = 0.771). The regression analysis facilitated the evaluation of the variation between SLA, respectively MLA and studied leaf parameters. From the analysis of the values of the coefficients of the regression functions, it was appreciated that the width of the leaves (w) had a stronger influence in the description of the leaf area, compared to L and Per.
foliar parameters, leaf area, model, Populus alba