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Wound healing rate in oriental beech trees following logging damage

Tavankar Farzam, Picchio Rodolfo, Lo Monaco Angela, Nikooy Mehrdad, Venanzi Rachele, Bonyad Amir Eslam

Drewno : prace naukowe, doniesienia, komunikaty

2019

vol. 62, nr 203

5--22

Beech is the most important commercial species in the Caspian forests of Iran. Selective cutting and harvesting methods may adversely impact the quality of the residual trees, as the injuries make the trees prone to future disease, insect infestations or timber defects. Although attempts to better understand how wounds affect the residual trees have been made in many different contexts, there are still few investigations on uneven-aged forests. In this study the key objectives were to determine and model the healing rate for different wound parameters (width, length, and area of wound); to analyse the relationship between wound healing rate (WHR), tree diameter growth and tree height growth; to analyse the WHR in relation to wound position on the stem; and to analyse the relationship between WHR, width and area of wound in DBH classes and social classes, with the aim of enabling the prognosis of logging wounds. Wounded beech trees were examined immediately after selective logging and after a 5-year period. The WHR was 31.2 ±7.7 cm2 year-1. The wound width healing rate (18.4 ±3.4 mm·year-1) was significantly higher than the wound length healing rate (4.5 ±1.6 mm·year-1). Only 12% of wounds were completely closed after a 5-year period, and 15 years are necessary for the complete closure of 80% of total wounds. The ratio of wound area to stem area at wound height (RWS) showed a more pronounced effect on diameter than on height. Regression analysis showed that WHR was correlated negatively with wound area and width and positively with tree diameter growth, but no significant relationship was found between height growth and WHR parameters. The WHR was significantly higher at an upper position than at a lower one, and statistical tests showed that the tree vertical layering classes had a significant effect on WHR. Finally, it was shown that WHRs in upper-storey trees are significantly higher than in the middle and lower storeys.

Conversion of instable primary forests in the lusatian post-mining landscape

Ertle C., Bartelt D.

Zeszyty Naukowe. Inżynieria Środowiska / Uniwersytet Zielonogórski

2007

nr 133 (13)

84-94

In the federal state Brandenburg in Germany about 464 000 ha of mainlymiddle aged Scots pine stands are planned to be converted. In addition, instable broad leaved forests like disintegrating monocultural birch and poplar stands on dumps of lignite mining need conversion. Forest owners feel unsure regarding the silvicultural treatment in these stands. Therefore, research is needed to develop strategies for a forest conversion practice in primary forests on dumps within the mining landscape. The urgency of conversion of primary dump stands with regard to the tree species exists in the decreasing order: poplar, birch and Scots pine. While conversion of young primary pine forests into mixed broad-leaved forests is not advisable because of unfavourable site conditions, suitable timber stands on dumps represent favourable pioneer crops appropriate for conversion. Derived from investigations practical advises are given about kind, strength and time of preparatory thinning for under planting and ongoing thinning. The nutrition potential of the soil substrate has to be considered. Furthermore, height growth and leave mass of under planted oaks are indicators for the forest treatment.