METHOD OF ANALYSIS OF COMPOSITION OF MEADOW GRASS ON HEIGHT OF TEST PLOT OVER EDGE OF SMALL RIVER

摘要

FIELD: agriculture.;SUBSTANCE: method comprises allocation on the small river or its tributary visually on the map or in-situ of plot of floodplain meadow. Then, on this plot downstream the small river or its tributary in specific areas at least three cross-sections of measurement in the transverse direction are marked. Along each cross-section at least three test plots are marked on each side of the small river or its tributary. After marking the height of location of the centre of each test plot is measured from the surface of the small river or its tributary, and then patterns of influence of the height of location of the test plots above the water edge on the performance of samples of grass are identified. Also assessment is made of the impact of the distinctive orographic features of relief and natural and man-made objects located inside and outside the selected plot. At each cross-section of measurements the specific sites are determined on changing the altitude. Then, using a level unit the altitude differences are measured between the centres of the test plots and the river edge. For the analysis of the species composition of the grass at a characteristic place of cross-section of measurements a peg is placed and then a square frame is stacked to form the peg as the centre. And without cutting grass the test plot becomes virtual. Then, on the virtual test plot inside a square frame the number of species of grass is counted, and recorded in the table with a common list on the rows of this table of all kinds of grass and herbaceous plants that at least once are found on the allocated plot of the small river. In the columns under the numbers of virtual test plots the unit is put in case of the presence of this species of grass and herbaceous plant and leave the cell of the table empty in case of the absence of the plant species, so the measurements are performed consistently of the presence of grass species in all virtual test plots. After that the units are summarised on the columns of the table and the number of species of plants in each virtual test site is calculated, and then by dividing the present number of plant species on the total number of species for all rows in the table the relative occurrence of species of grass on each virtual plot is calculated. Then the wave patterns of change in the relative occurrence of species are identified depending on the height of the virtual test site above the water edge by statistical modelling.;EFFECT: method enables to improve the accuracy of accounting the presence of species of grass and herbaceous plants, taking into account the measurement with the level unit of height of location of the plots without cutting the grass.;5 cl, 5 dwg, 3 tbl, 1 ex