Timberline ecosystems react very markedly to human impacts. Such impcts have lastet for hundreds of even several thousands of years, andtheir results ca exceed those of primary climatic and geodynamic effects. Human impacts at the timberline, involving changes in forest areas, structures and site conditions, can cause timberline depressions and degradation of the remaining stand, with local to refional consequences: shift in the natural distribution of vegetation, a decrease in the forests capacities for protecstion and production, the disruption of the water cycle and hydrologic budget, and an increased probability of natural catastrophes. Extensive land use for technical over-development for purposes of tourism are a current burden on the timberline ecosystems too. Increasing air pollution also effects timberline ecosystems.
