我国特有植物银杉的资源、分布及其环境

我国银杉自1955年发现以来,陆续发现了它的新分布,至今已知在四省、区7个分布区的30多个分布点上,自然生长着银杉3200余株。它们是:广西花坪林区(越城岭南部)6个点有银杉1040抹,其中高5米以上的68株,1～5米的49株,1米以下的923株,最高21.1米,最大胸径83厘米;广西大瑶山4个点有银杉143株,其中高10米以上的94株,1～3米的3株,1米以下的46株,最高30米,最大胸径79.2厘米;湖南罗汉洞(越城岭北部)2个点有银杉58株,5米以上的有45株,最高18米,最大胸径43厘米;湖南罗霄山脉八面山有银杉707株,高1米以上的334株,最高24米,最大胸径46厘米;四川南川金佛山(大娄山东段北部)6个点有银杉527株,其中成年树400余株,最高17米,最大胸径50厘米;百枝山有银杉52株,最高8米,最大胸径27厘米;贵州道真沙河林区(大娄山东段南部)3处12个点有银杉729株,其中高5米以上的105株,2～5米的209株,1～2米的111株,1米以下的304株,最高18.8米,最大胸径48厘米;贵州桐梓白菁有银杉10株,高4～5米的2株,1～3米的6株,1米以下的2株。 银杉分布区范围自北纬24°5′～29°13′14″,东经107°10′～113°40′。其垂直分布自海拔940～1840米,金佛山银杉分布最高,为1600～1840米;罗汉洞银杉分布最低,为940～1060米。分布区内,年均温8.2°～17℃,绝对最低温

CATHAYA ARGYROPHYLLA, AN ENDEMIC TREE OF CHINA, ITS RESOURCES, DISTRIBUTION AND ENVIRONMENT

After the initial discovery in Guangxi Province, South China, of Cathaya argyrophylla in 1955, new records have been reported one after another, especially in recent years. Up to now over 3266 wild Cathaya trees have been found and they are distributed at about thirty points in 7 subregions, extending into 4 provinces. The trees are at: Huaping (花坪) forest region of Guangxi (south part of Yuechcng Range越城岭) , 1040 Cathaya trees dispersed at 6 points, among them are 68 trees over 5 m, 49 trees 1-5 m, 923 young trees under 1 m; the tallest one is 21.1 m, the biggest trunk diameter at breast height is 83 cm; Dayaoshan (大瑶山) in Guangxi, 143 trees dispersed at 4 points, 94 trees over 10 m, 3 young trees 1-3 m, 46 trees under 1 m, the tallest one is 30 m, the biggest trunk diameter at breast height is 79.2 cm; Luohandong (罗汉洞) Cave in Hunan Province (north part of Yuecheng Range), 58 Cathaya trees dispersed at 2 points, 45 trees over 5 m, the tallest one is 18 m, the biggest trunk diameter at breast height is 43 cm; Luoxiao (罗霄) Range in Hunan Province, 707 Cathaya trees at one point, 334 trees over 1 m, the tallest one is 24 m, the biggest trunk diameter at breast height is 56 cm; Nanchuan (南川) Jingfushan (金佛山) in Sichuan Province, 527 Cathaya trees dispersed at 6 points, 400 adult trees, the tallest one is 17 m, the biggest trunk diameter at breast height is 50 cm; Baizhishan (百枝山) in Sichuan Province, 52 Cathaya trees at one point, the tallest one is 8 m, the biggest trunk diameter at breast height is 27 cm; Daozhen (道真) forest region in Guizhou Province, 729 Cathaya trees dispersed at 12 points, 105 trees over 5 m, 209 trees of 2-5 m, 111 trees of 1-2 m, 304 young trees under 1 m; the tallest one is 18.8 m, the biggest trunk diameter at breast height is 48 cm; Tongzi (桐梓), Guizhou Province, 10 Cathaya trees at one point, 2 trees of 4-5 m, 6 trees 1-3 m, 2 trees under 1 m.Cathaya grows at latitudes 24 °9'-29°13'14" N and longitudes 107°10' - 113°40' E, at elevations of 940-1840 m; 1600-1840 m in Jingfushan at the highest level, 940-1060 m in Luohandong at the lowest level. Over its whole range, the average annual temperature varies from 8.2-17℃. the absolute temperature minimum varies from -5--15℃, and annual rainfall is usually over 1400 mm.Cathaya trees usually grow in extremely exposed environments such as narrow, high and precipitous ridges or summits. The rock strata of its area are almost always that of pre-Cambrian age.Within its range, Cathaya is frequently associated with other important plants. In Huaping, they are Pinus kwangtungensis, Fokienia hodginsii, Schima argentea, Nyssa sinensis etc. In Dayaoshan, they are Tsuga longibrocteata, Pinus kwangtungensis, Lithocarpus chrysocoma etc. In Jingfushan they are Schima superba, Quercus stewardi-ana, Cornus controversa etc. In Luoxiao Range, they are Tsuga tchekiangensis, Fokienia hodginsii etc. In Luohandong, they are Tsuga longibracteaia, Quercus stewardi-ana, Castanopsis eyrei etc. In Daozhen, they are Cunninghamia lanceolata, Pinus tai-wanensis var. damingshanensis, Quercus glandulifera, Q. glauca,Q. engleriana, Lithocarpus hancei. In Tongzi they are Pseudotsuga sinensis, Liquidambar formosana, Castanopsis eyrei etc.