美国红木林与红木国家公园

Redwood forest and redwood national park of the USA

美国红木指生长在美国西北海岸的北美红杉Sequoia sempervirens与巨杉Sequoiadendron giganteum的统称。前者称海红木,分布北加州海岸绵延至俄勒冈州南部州界;后者称山红木,分布加州中北部内华达山脉西坡沟谷。它们分别为世界最高和体积最大的长寿植物。红木林是原始复杂的生物群落。红木在史前是北美地区代表植物,后因环境变迁,至目前仅剩一个小的生存区域。美国政府为保护现有红木林,建立了多个红木国家公园和红木州立公园。联合国教科文组织亦将红木国家公园与附近3个红木州立公园列入世界遗产和国际生物圈保护区中心。红木有多种用途,树形壮丽,是城市绿化的优良植物。红木公园的巨树与幽谷,吸引无数游客,游客绝大部分能自觉遵守有关保护法规。

American redwood is the general name of both Sequoia sempervirens and Sequoiadendron gigantuem because both of them belong to the family of Taxodiaceae, a reddish brown woods. The first one, S. sempervirens, sometime is called ＂ocean-redwood＂, whose native habitat is only in the Northern California coastal forests ecoregion, on the Northern California Coast and several miles into Oregon. The second one, S. gigantuem, is also called ＂mountain- redwood＂, whose native habitat is only on the western slopes of the Sierra Nevada Range in central eastern California. The trees live in warm, humid and foggy environment. They grow fast with strong environmental resistant capability. The trees in Sequoioideae hold the record for the tallest and largest trees in the world. Redwood is the main plant in Northern America during the prehistorical time. Due to environmental change, now they live only in a small area. To protect the redwoods, USA government established numerous redwood national parks and redwood state parks. UNESCO （United Nations Educational Scientific ＆ Cultural Organization） also listed redwood national parks and its nearby three state parks in the World Heritage and International Biosphere Reserve Center. With gorgeous and beautiful shapes, redwood has many uses and also is an excellent plant for metropolitan greenbelt. The gigantic trees and thick valley attract countless tourists to the redwood parks and most visits follow the guidance of the parks.