Wyniki wyszukiwania - Biblioteka Nauki

Ten serwis zostanie wyłączony 2025-02-11.

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

1 Sylwan

1 2017

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Dokładność wybranych metod określania miąższości drewna sosnowego wyrabianego w kłodach

100%

Giedrowicz A. , Staniszewski P.

nr 11

In 2015, approximately 38.5 million m³ of round wood was harvested in Poland, and this volume is constantly growing. Scots pine (Pinus sylvestris L.) occupies about 58.5% of the forest area in Poland and is the species of the most economic importance. Along with the changes in the timber market, mainly due to the development of technology for the harvesting and processing of wood raw materials, the consumers interest in stem wood has increased. The State Forests in Poland have developed their own system for timber volume calculation that is based on the measurement of the under−bark diameter at the thinner end of the log. The aim of the study was to evaluate the accuracy of three methods of determining the harvested timber volume: Huber's and Smalian's dendrometric formulas and the method currently used by the State Forests. The study was conducted in the Choczewo Forest District (N Poland). In total, 193 logs collected from five forest ranges and from two forest habitats (fresh mixed broadleaved and fresh mixed coniferous forest) were measured. The relative error calculated as the relative difference between log volume obtained by the dendrometric formula and the real volume determined with section−wise method was statistically analysed. Mean errors obtained with all tested methods of volume determination differ significantly from zero, which indicates the systematic error of volume determination. The greatest errors are generated by the method used by the State Forests. The volume obtained with this method is underestimated on average by over 14%.