Estimativas de biomassa acima do solo de Piper mikanianum por métodos indiretos

Abstract

This study aimed to evaluate regression models to estimate the biomass of rush and leaves of Piper mikanianum. For this purpose, in the municipality of Silveira Martins - RS, in secondary formations of the Seasonal Deciduous Forest, three sample locations were selected, from where they were collected, of soil for color identification using a Munsell chart, as well as the biomass above the soil, composed of stems and leaves. In the Laboratory, the plants were sectioned into two components: a leafy part, composed of a stem with leaves, and a stem without leaves. The leafy part was measured in ply length (CF), which is the sum of the length of each branch with leaves. Linear measurements of the leaves were taken, such as length (L) and width (L), and then the number of leaves (NF) was counted. From the stem, its length and diameter at the median height (D) was taken. These leaves and stems were weighed and called green biomass by the direct method and dry biomass using an air circulation oven at 50°C until constant weight was obtained. The biomass of the green stem (BHV) and dry stem (BHS) and the green leaf (BFV) and dry leaf (BFS) biomass. These were evaluated using GLM regarding the influence of the measured variables and the effect of the location. Soil color differed between locations, however, in most cases the location did not interfere in the dry biomass estimate. Using the analysis of covariance, it was confirmed that only the variable ply length (CF) was not a good estimator, the other variables tested are capable of estimating the average biomass of Piper mikanianum, highlighting the combined variables resulting from the product of dimensions and quantities, CLNF for plywood and D²C for stem. As a result, it was found that the dry and green leaf biomass can be estimated as a function of leaf laminar measurements and their number, with the models: BFV= 1.0518 + 0.0089 * CLNF and BFS= 0.2741 + 0.0031 * CLNF, and stem biomass can be estimated using length and diameter measurements, using models BHV = 0.3330 + 0.0086 * D²C and BHS = 0.4018 + 0.0014 * D²C.