The Economist(Hitting the Slopes-12/28/09) is a master at scrolling thru scientific journals and condensing important, interesting data so the non-scientist can read and understand it.
In a recent article they compared the construction and administration of ski slopes in the US to those in Europe as far as their environmental friendliness.
-That ski slopes may be inherently bad for the environment since,"Trees are chopped down to make way for trails that skiers can use. This breaks up forest habitat and stresses local species that are disturbed not only by the construction but also by the skiers themselves during the day and the maintenance crews at night."
-Many of the European slopes are above the tree line and do not require tree removal whereas the US slopes are below the tree line and involve clearing for trail manufacture either by total clear cutting with machines or by more sporadic cutting by man
-Two UCal-Davis scientists did a study on the two types of US clearing and found, "that the way in which the trails had been constructed accounted for nearly all the difference in the number of plants and the diversity of species present. Ski runs that were machine-graded and cleared of boulders and stumps tended to have small herbaceous plants growing on them and little else. Such growth is typical in regions of great environmental disturbance and usually represents the first steps in a region towards ecological recovery. The trails that had simply been cleared of trees were dominated by shrubs, which usually indicate terrain that is ecologically well developed."
The UCal scientists decided that," ski runs cleared of only trees offer some ecological benefits because they locally increase native species diversity and habitat variety without creating harsh boundaries that leave species near the forest edge exposed."
and that,"Instead, any new ski runs on either side of the Atlantic Ocean and elsewhere should be created at relatively low altitudes and by tree clearance rather than machine-grading, a lesson that also holds true for firebreaks, power line rights-of-way and temporary access roads.
It reminds us of golf courses which we have a lot of in Florida where we live.
We assume that golf courses are better than total clear cutting of habitat and building parking lots but they do absolutely change the habitat from the way it was before and with the drainage required certainly hurt native swamps.
Sadly any human recreational involvement leaves a mark on any habitat that is changed