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When logging began in British Columbia, Canada, in the late 19th century, the overriding concern was to harvest timber in the most economical fashion. Reforestation, aesthetics and protection of fish and wildlife habitat were not issues of great concern.〔(BC Forest Practices Branch 2006 Alternatives to Conventional Clearcutting )〕 In a presentation to the Natural Resources Committee of the Canadian House of Commons in April 1994, Patrick Moore of Greenspirit, a founding member of Greenpeace, said destructive forest practices – not the concept of clearcutting – led to a high level of public concern over clearcutting and other forest management issues.〔(Greenspirit Clearcutting – Right or Wrong? . . . Both! )〕 The use of clearcutting with reserves and variable retention has increased in British Columbia since the late 1990s, and the average size of clearcuts has decreased, improving the balance of environmental and economic objectives.〔(The State of British Columbia’s Forests P. 150 )〕 == Clearcutting trends == Until the mid-1990s, most harvesting on public lands in British Columbia involved clearcutting, From 1970 to 1998, clearcutting systems were applied on 87% of the area harvested on public land, and various partial cutting systems on 13%.〔(The State of British Columbia’s Forests P. 144 )〕 Advances in knowledge and a shift in the balance of objectives towards conservation of biological diversity led to the use of clearcutting with reserves and variable retention systems. Since 1999, 44% of the area on public lands has been harvested by clearcutting, with the remaining 56% harvested with partial cutting systems.〔(The State of British Columbia’s Forests P. 144 )〕 In 2009/10, 15% of harvesting on public lands was by clearcutting; the rest used clearcuts with reserves and partial cutting systems.〔(Silvicultural Program Statistics )〕 Social concerns about large clearcuts led to a decrease in average size from 45 hectares on public lands in 1989 to 30 hectares in 2006.〔(The State of British Columbia’s Forests P. 145 )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Clearcutting in British Columbia」の詳細全文を読む スポンサード リンク
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