我国金花茶组植物的地理分布

世界产金花茶组植物22种,其中我国20种,特有18种,仅产广西。其分布区在北纬21°30′—23°40′,东经106°40′—108°35′,北界基本上与广西北热带半常绿季雨林、湿润雨林地带北界吻合。该组植物分布于石灰(岩)土的13种,红壤的7种。它们出现的地段比较固定,天然林下,沟谷或溪边处,相对高度10—15米;峰丛圆洼地底部和荫蔽的坡面下部。该组植物个体最多的地区(几何中心)一个在防城县,一个在龙州县;种类最多的地区(最大变异中心)一个也在龙州县,9种,一个在扶绥县,7种。该分布区从南到北分化成六个小分区。其垂直分布一般在海拔700米以下。水平分布种的更替表现为:北纬21°31′为小瓣金花茶等五种;北纬22°10′—22°45′为鼻岗金花茶等八种更替;北纬22°50′为顶生金花茶等三种更替;北纬23°40′为平果金花茶更替。金花茶分布幅度最宽,可由北纬21°31′到22°55′。在土山,东西以东经107°30′为界,以东为金花茶等四种,以西为小瓣金花茶等二种。

GEOGRAPHIC DISTRIBUTION OF CAMELLIA SECTION CHRYSANTHA FROM CHINA

There are tweenty two species of Camellia Section Chrysantha throughout the world,tweenty of them in China,among them eighteen species are endemic to China and confined to Guangxi.The range of this section is between latitude 21°30'to 23°40' N to the border of north tropic zone and longitude 106°40' to 108°35' E.There are thirteen species in calcareous soil and seven species in red soil.They are distributed quite regular and generally occur under natural forest along the streams in the valley with relative elevation of 10-15 meters,or at the bottom of the limestone hill peaks and depression at the foot on the shady limestone hill slope.The regions of the section with abundant individuals(the geometric centre)appear in Fangchen Xian and Longzhou Xian;one of the regions with plentiful species(the greatest variable centre)appears in Longzhou Xian with 9 species,and the other in Fusui Xian with seven species.The floral regions of this section in China may be divided into six subregions.In vertical distribution,species of the section generally appear at the elevation of below 700 meters.In horizontal distribution,the successive replacement of the species has revealed as follows:Camellia parvipetala and four species are distributed at latitude 21°31' N;C.longganensis and seven species northwards between latitude 22°10'-22°45' N;C.terminalis and ten species at latitude 22°50' N;C.pinggouensis at latitude 23°40' N.While C.chrysantha,the widely dispersed species,appears between latitude 21°31'-22°55' N.In the range of the red soil,the longitude 107°30' E is the boundary line,in the east of this line there are C.hrysanthac and othe forur species,in its west,the species are replaced by C.parvipetala and one species.There are tweenty two species of Camellia Section Chrysantha throughout the world,tweenty of them in China,among them eighteen species are endemic to China and confined to Guangxi.The range of this section is between latitude 21°30'to 23°40' N to the border of north tropic zone and longitude 106°40' to 108°35' E.There are thirteen species in calcareous soil and seven species in red soil.They are distributed quite regular and generally occur under natural forest along the streams in the valley with relative elevation of 10-15 meters,or at the bottom of the limestone hill peaks and depression at the foot on the shady limestone hill slope.The regions of the section with abundant individuals(the geometric centre)appear in Fangchen Xian and Longzhou Xian;one of the regions with plentiful species(the greatest variable centre)appears in Longzhou Xian with 9 species,and the other in Fusui Xian with seven species.The floral regions of this section in China may be divided into six subregions.In vertical distribution,species of the section generally appear at the elevation of below 700 meters.In horizontal distribution,the successive replacement of the species has revealed as follows:Camellia parvipetala and four species are distributed at latitude 21°31' N;C.longganensis and seven species northwards between latitude 22°10'-22°45' N;C.terminalis and ten species at latitude 22°50' N;C.pinggouensis at latitude 23°40' N.While C.chrysantha,the widely dispersed species,appears between latitude 21°31'-22°55' N.In the range of the red soil,the longitude 107°30' E is the boundary line,in the east of this line there are C.hrysanthac and othe forur species,in its west,the species are replaced by C.parvipetala and one species.