Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 12

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  drzewa uszkodzone
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Research was carried out in Scots pine (Pinus sylvestris L.) stands damaged by strong wind in six locations in Poland. The aim of this study was to analyse the radial variation of compressive strength parallel to grain in the wind−broken trees and neighbouring survivors. Strength tests were conducted in moisture above saturation fibre point. There were no significant differences in the radial distribution of the compressive strength between the compression side (breakage side) and the tension side (the opposite one). Either there were no significant differences between compression strength of damaged trees and neighbouring standing trees.
The aim of the study was to evaluate the area and volume of the windthrows caused by a downburst, which occurred early morning on July 8th , 2015 in the Międzylesie Forest District (south−western Poland). The wind velocity reached 270 km/h and the phenomenon caused damages similar to those observed after the hurricane. The most affected forest ranges included: Różanka, Nowa Wieś, Lesica, Goworów, Jodłów and Smreczyna. To evaluate the area of the windthrow in particular forest stands, the remote sensing data were used, whereas to estimate the total wood volume we applied the growth model and the average volume of the particular forest stands, gathered in the State Forests Information System (SILP) database. The volume of the windthrow evaluated by the forest rangers during some local investigation equaled 103 thousands m³, while one calculated using the SILP database – 161 thousands m³ and with the growth model – 168 thousands m³. The forest service estimations were underestimated. According to the model of the wind damage risk, most of the forest stands in the Międzylesie Forest District were highly or very highly endangered by the strong winds. The presence of the windtrhow is very dangerous either for people or the surrounding forest (due to the risk of pests outbreak). Therefore it demands immediate decisions and actions from the forest service, which need reliable and quickly accessible data. The information provided with the satellite imagery, the risk model and the growth model may accelerate the decision−making process and optimize the damage disposal. Satellite imagery also enables to estimate the amount of damage on the areas, which are hardly available for the foresters and their vehicles. Due to their high usefulness, growing availability and declining prices, these tools should be introduced to local forestry as quickly as possible.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.