НОРМАТИВНО-ДОВІДКОВІ МАТЕРІАЛ ДЛЯ ТАКСАЦІЇ ДЕРЕВ І ДЕРЕВОСТАНІВ ЛИПИ СЕРЦЕЛСТО

Abstract

STANDARDS AND REFERENCE MATERIALS FOR LINDEN
TREES AND TREE STEAMS MENSURATIONS

O. Soshenskyi, V. Svynchuk, E. Khan.

System of normative and reference materials for mensuration of linden trees and tree stands

 The scientific article deals with quantity and quality characteristics of volume stock of linden tree stands, peculiarities of their biometric structure and developing of corresponding standards for forestry.

Statistical analysis of availability of the linden stands has been performed on the base of the latest inventory data base with characteristics of Ukrainian forests. The verification of mensuration normative of linden tree stands has been done, and the necessity of developing of a number of forest estimation standards for the linden tree stands was proved on its basis. A sufficient amount of research material has been collected and statistical analysis has been performed. The results of research of the basic forest mensuration indicators of linden trees and stands are presented. Methods of developing appropriate forest mensuration standards are outlined.

Analysis of existing in Ukraine forest estimation standards showed that normative-informational support for linden, practically, is non-available, in particular, hitherto there are no tables of linden trunks volume, distribution of merchantable trees volume by size-quality categories and industrial assortment, bit scales and assortment tables for young and middle-aged stands, commodity and standard tables etc.

Statistical analysis of forest estimation characteristics of linden tree stands of Ukraine and justification of the necessity of forest estimation research of this species with further development of forest estimation standards was carried out.

Studying of height-diameter ratio of tree trunks is a very important issue in forest valuation. The previous experience of scientists affirms that there is a connection between these two indicators, thus the research of regularity data during the development of forest evaluation standards is required. During the research of height-diameter ratio of linden tree trunks the materials of 40 sample areas laid in stands of different age groups (17 in immature and middle-aged stands, 23 in premature, mature and overmature stands) were used. Sample areas were laid in the most typical for the wood species under study types of site indexes. Studying of height -diameter ratio of tree trunks of linden stands was conducted with the help of method developed by Forest Mensuration and Forest Inventory Department of the National University of Life and Environmental Science of Ukraine. According to this method the above mentioned ratio was analyzed in relative quantities, because it makes easier the process of modeling of relative heights. According to the results of research mathematical models of relative heights of different age (1 – immature and middle-aged stands; 2 –premature, mature and over mature stands) linden stands were developed. During the development of discharge tables numeration of discharges and interval between them were conformed to the current assortment tables. In the result the limits of discharge heights according to the thickness level were received. Discharge tables for immature and middle-aged linden stands was developed for the first time.

During the research of the linden tree trunks form factor the materials of 218 model trees were used. The research data collection was conducted in the pure and mixed stands including linden ones in Ukrainian forest-steppes, particularly in Kyiv, Vinnytsia, Sumy, Cherkasy, and Chernivtsi regions. Before the development of mathematical model of a form factor the dependence of this index on other trunks indexes was investigated with the help of correlation analysis. It turned out that the index of nontaperity of linden trunks is generally characterized by inverse connection both with height and tree diameter (therefore, pair coefficient of correlation is -0,41 and-0,47 and the multiple one is 0,47). Generally speaking, the specified dependency is rather weak, but it is statistically significant at the 5% level (r_крит.=0,14).  Therefore, further the established relationships were taken into consideration. The next step was to determine the difference between the form factors of small-leaved linden trunks, which is growing in different regions, especially in the Western forest-steppe and Dniester-Dnieper forest- steppe forestry districts (according to A. Hensiruk). Using Fisher’s F-test and Student's t-test, the statistical hypothesis concerning the difference between the tree trunks form factors in different regions was checked. Since the calculated values of F- and t-tests don’t exceed the tabular values, at the 5% level of significance it is necessary to reject the hypothesis concerning the difference between both variances and average values of a form factor of linden’s trunks in different forestry districts. According to the results of research mathematical models of relative heights of linden stands was developed. On the basis of the developed model of a form factor, a project of tables of trunks’ volume depending on their diameter and height was developed.

During field researches of size-quality structure of linden tree trunks well-known in the forest estimation methods were used. Tree trunk estimation and its assortment distribution were conducted on the throws of main use as well as on temporary sample areas. Assortment distribution of tree trunks was done in accordance with the GOST 9462-88. During the modeling of size-quality structure of linden tree trunks the method based on the rules of trunk volume distribution on separate categories in relative values was used. As a result, mathematical models of size-quality structure of linden tree trunks were obtained. According to the results of conducted researches the statistical analysis of experimental data was done, mathematical models of height, tree density, and size-quality structure were developed, on the basis of which height scale, volume and assortment tables were studied. The comparison of developed assortment tables with the current ones shows significant differences between them, for most thickness levels the deviation of production of merchantable timber makes up more than 10%.

The results of research of biometrics structure of linden tree stands according to the diameter were given. On the basis of β-distribution mathematical model of distribution series of trees according to diameter and categories of technical competence was studied. The tables of merchantability structure of premature and mature linden tree stands were made.

A system of standards for the valuation of linden stands has been developed –discharge tables for linden stands, tables of the volume of linden tree trunks, tables assortment of size-quality structure, category assortment tables for the linden tree stands different age, tables of merchantability structure of premature and mature linden tree stands were developed. The statistical verification and substantiation of the adequacy of the developed mathematical models has been carried out.