METHOD TO IDENTIFY ECOLOGICAL CONDITION OF FORESTS

摘要

FIELD: agriculture.;SUBSTANCE: method to identify ecological condition of forests includes probing from an aerospace carrier, measurement of a spectral radiance coefficient (SRC) of a leaf canopy, using measured SRC values, calculation of vitality (g) and red lesion (r) indices, production of 2D images of brightness field I(x,y) of the leaf canopy in the green (G) and red (R) regions of the visible range, estimation of forest lands condition using measured values of SRC and I(x,y). SRC and I(x,y) of one and the same sections are synchronously measured by a spectrometre and digital cameras of G and R ranges, with matched fields of view, which are coaxially installed on a movable remotely operated platform. A vegetation index (NDVI) is calculated for a plantation on the analysed area in the near IR range. The resulting matrix (O) of the image is generated by means of pixel-by-pixel addition of (G) and (R) image matrices. Program processing of image matrices signal is carried out to calculate the average frequency of space spectra of the resulting matrix and matrix (R) accordingly F_av0, F_avR, and also the area of leaf canopies reliefs S_r0 and S_rR. The area stand characteristics are calculated: volume V₀, V_R and diametre of an average tree top D₀=1/F_av0, D_R=1/F_avR. The weight coefficient α is defined via ratios α=(V_R/V₀)(D_R/D₀)^1.2 of the weak trees stock coefficient V_RD_R ^1.2 to the total coefficient of the section stock V₀D₀ ^1.2. The extent of weakness Q of the section stand is defined using regression dependence calibrated by measurements of reference sections, of the following type: Q=0.6(gNDVI)^-1(r(l-NDVI))^1.3(V_R.V₀)(D_R.D₀)^1.2.;EFFECT: method provides for efficiency and accuracy of forest ecological condition assessment.;6 dwg, 3 tbl, 1 ex