Ocena efikasnosti različitih sistema rada na poslovima seče i izrade drvnih sortimenata

Abstract

Seča stabala i izrada drvnih sortimenata u Srbiji se u preko 90% slučajeva obavlja motornim testerama. U literaturi se navodi da je posao radnika koji rukuje motornom testerom jedan od najtežih, ali i najopasnijih. Osnovni cilј ovog istraživanja je bila ocena efikasnosti i izbor odgovarajuće organizacione forme rada u seči stabala i izradi drvnih sortimenata u različitim uslovima rada, istovremeno uvažavajući više faktora. Ovo istraživanje obavljeno je na 7 oglednih površina (5 u ravničarskom i 2 u brdsko-planinskom predelu), gde su seča stabala i izrada drvnih sortimenata obavljene motornim testerama Stihl i Husqvarna, koje su se razlikovale po snazi. Istraživane su tri različite forme rada (1M (radnik koji rukuje motornom testerom) +0R (pomoćni radnik), 1M+1R i 2M+0R) u sastojinama različitih vrsta drveća i različitim vrstama seče (čista seča u zasadima topole, proredna seča u sastojini hrasta i prebirna seča u sastojini bukve i jele). Utvrđeno je da postoje statistički značajne razlike u ostvarivanju učinaka između organizacionih formi rada, ali i između vrste drveća. Potrošnja goriva najviše zavisi od prečnika stabla na prsnoj visini, zatim od vrste drveća, a tek onda od snage motorne testere i organizacione forme rada. Utvrđeno je da je se najmanja potrošnja goriva i maziva, ali i potrošnja energije kao i emisija štetnih gasova ostvaruje kombinacijom dve motorne testere u sastojini bukve (jedne veće i jedne manje snage), u organizacionoj formi rada 2M+0R. Utvrđeno je da na štete na preostalim stablima u seči stabla izradi drvnih sortimenata najveći uticaj imaju prečnik posečenog stabla, zatim nagib terena i sklop sastojine, dok na štete na podmlatku najveći uticaj ima veština rukovaoca. Ukupno opterećenje dvojice radnika koji rukuju jednom većom i jednom manjom testerom u proseku je za 11% manje u odnosu na grupu radnika koji rukuju dvema testerama veće snage, pa je i sa ergonmskog aspekta povoljnija varijanta kombinacije veće i manje testere (kao i kod potrošnje goriva i maziva).

Felling and processing of wood assortments in Serbia is performed with chainsaws in over 90% of cases. It is stated in the literature that the job of a chainsaw operator is one of the most difficult but also the most dangerous ones. The main goal of this research was to evaluate the efficiency and choose the organizational form of work in tree felling and wood assortments processing under different operating conditions, while taking into account several factors. This research was carried out in 7 sample plots (5 in a lowland area and 2 in a hilly-mountainous area), where the felling of trees and wood assortments processing were performed with Stihl and Husqvarna chainsaws, of different powers. Three different forms of work (1 worker with chainsaw (C), without assistant (A) – 1C+0A, 1C+1A and 2C+0A) were investigated in stands of different tree species and different types of felling (clear felling in poplar plantations, thinning in oak stands and selection cutting in a beech and fir stand). It was established that there are statistically significant differences in the achievement of results between the analyzed organizational forms of work, but also among the tree species. Performance increases with an increase in diameter class in all organizational forms of work. Fuel consumption mostly depends on the diameter at breast height, after that on the tree species, and only then on the power of the chainsaw and the organizational form of work. It was found that the lowest fuel and oil consumption, as well as energy consumption and emission of harmful gases, are achieved when two chainsaws in beech forest (one of higher and one of lower power) are combined, in the organizational form of work 2C+0A. It was established that the diameter of the felled tree, the slope of the terrain and the composition of the stand have the highest impact on the damage to the remaining trees in felling and wood assortment processing, while damage to the regeneration is most influenced by the operator's skill. The load of two workers who handle one larger and one smaller saw is on average by 11% lower compared to the group of workers who handle two saws of higher power, so from an ergonomic point of view (as well as in terms of fuel consumption and lubricants), the combination of a larger and a smaller saw is more favourable.