Google

Yahoo! JAPAN



sualgifti LINK集

The term subalpine refers to the biotic zone immediately below tree line around the world. Species that occur in this zone depend on the location of the zone on the Earth.Trees in subalpine zone often become krummholz (crooked wood, stunted and twisted). At treeline, tree seedlings may germinate on the lee side of rocks and grow only as high as the rock provides wind protection. Further growth is more horizontal than vertical, and additional rooting may occur where branches contact the soil. The resulting low growth of dense trees is called krummholz. Snow cover may protect krummholz trees during the winter, but branches higher than wind-shelters or snow cover are usually destroyed. Well-established krummholz trees may be several hundred to a thousand years old.[

The oldest single living organisms known are bristlecone pines, though some plants such as creosote bush or aspen form clonal colonies that may be many times older. Recently, Swedish researchers discovered a self-cloning spruce in Dalarna that has been dated to just under 10,000 years old[1] [2]. The existing growth in clonal colonies sprang as shoots from older growth so there is an unbroken chain of life that sometimes dates back several tens of thousands of years. However, the original ancient growth in these colonies is long dead. The oldest bristlecone pines are single plants that have been alive for a little less than 5,000 years. These very old trees are of great importance in dendrochronology or tree-ring dating.The oldest (acknowledged) living organism known is a bristlecone pine tree nicknamed "Methuselah" (after Methuselah, the longest-lived person in the Bible). Methuselah is located in the Ancient Bristlecone Pine Forest in the White Mountains of eastern California, however its precise location is undisclosed by the U.S. Forest Service to protect the tree from vandalism.[1] The age of Methuselah was measured by core samples in 1957 to be 4,789 years old.In the Snake Range of eastern Nevada Donald R. Currey, a student of the University of North Carolina, was taking core samples of bristlecones in 1964. He discovered that "Prometheus" in a cirque below Wheeler Peak was over 4,000 years old. His coring tool broke, so the U.S. Forest service granted permission to cut down "Prometheus". 4,844 rings were counted on a cross-section of the tree, making "Prometheus" at least 4,844 years old, the oldest non-clonal living thing known to man.

出典：フリー百科事典『ウィキペディア（Wikipedia）』




Copyright (C) 2009　sualgifti LINK集　All Rights Reserved.

リンク集１　リンク集２　リンク集３　リンク集４