tailieunhanh - Báo cáo lâm nghiệp: "Environmental risk assessment based on semi-quantitative analysis of forest management data"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài: Environmental risk assessment based on semi-quantitative analysis of forest management data. | JOURNAL OF FOREST SCIENCE 57 2011 3 89-95 Environmental risk assessment based on semi-quantitative analysis of forest management data L. Kulla1 R. Marusák2 ỵ Forest Research Institute in Zvolen National Forest Centre Zvolen Slovakia 2Faculty of Forestry and Wood Sciences Czech University of Life Sciences Prague Prague Czech Republic ABSTRACT The paper deals with environmental risk assessment in prevailingly unnatural spruce Picea abies L. Karst. forests in three regions with different patterns of forest damage in the Slovak part of the West Carpathians. Logistic regression was used to estimate the effect of 7 site-related 5 stand-related and 2 anthropogenic factors on the probability that critical forest damage will occur. The results show that regression models can describe cause-effect relationships in regions with different regimes of forest decline. Stand age proportion of spruce and distance from the focus of biotic agent activity predicted decline in two regions with generally lower elevation in northern Slovakia Kysuce and Orava . In a mountain region Low Tatras the importance of factors contributing to the static stability of trees and position towards dangerous winds increased significantly. The quality of the derived models and prospects for their usefulness in risk assessment are discussed. Keywords ecological factors forest damage forest management logistic regression Norway spruce risk assessment The general forest management scheme in Europe primarily aims to achieve high-quality and large-dimension timber production which depending on site conditions and tree species growth characteristics usually requires a growing period of about 100 years or longer. A wide range of disturbances typically occurs during this period. Because a profit is expected at the end of the forest production cycle rotation period each aspect or incidence of damage causes a loss in value. Therefore one of the main tasks of forest management is to reduce such damage by the proper