In Bulgaria, the species is in danger due to habitat loss caused by selective logging, human settlements and natural causes like acid rain and soil pollution.
42.
The company introduced innovative and progressive practices to the British Columbia forest industry such as selective logging, reforestation, improvements in workplace safety and better wages and benefits.
43.
But selective logging leaves the forest floor littered with less valuable trees knocked down accidentally, and they quickly dry out and turn into eventual fuel for fires.
44.
Bischel cited the Quincy Library Group plan, a forestry initiative developed by small Sierra communities that emphasizes selective logging to reduce fire danger, as a better approach.
45.
His research supports the use of intentionally set small fires and selective logging as ways to eliminate small trees and return the forest to a more natural condition.
46.
Nepstad says there has been so much selective logging _ something not visible from satellite photos _ in the Amazon that official deforestation figures are far too low.
47.
But scientists acknowledge that selective logging can actually help a forest grow and provide room for some animal species, like elephants and bongo, to forage, socialize and reproduce.
48.
Some habitat is threatened by expansion of the agricultural and pastoral frontier, gold mining, and selective logging that erodes the genetic diversity of a few valuable timber species.
49.
Selective logging and clearing the forest for farmland sets the stage for ever more frequent and fierce fires in forests that until recently were thought to be nearly fireproof.
50.
Researchers are also finding that in some species, when the number of flowering trees in an area is reduced, as through selective logging, this long-distance mating can be disrupted.
