金花茶组植物种群生态的初步研究

A Preliminary Study on the Population Ecology of Camellia sect.nitidissima

关键词:  金花茶组  种群生态

Key words:  Camellia sect  nitidissma  population ecology

摘要:

金花茶组23种属常绿阔叶小高位芽植物,为广西季雨林、沟谷雨林的种群。分布于沟谷、溪边、圆洼地底部和湿度及荫蔽度较大的坡面.林内光照度一般在320~600勒克司,湿度77%~94%。岩溶地貌上13个种的种群叶片灰分和钙元素含量分别比常态侵蚀地貌上7个种的种群高0.8~1倍和3~5倍。凹脉金花茶、金花茶、东兴金花茶、显脉金花茶种群对湿度条件要求最高,小瓣金花茶种群较耐旱。成熟的群落,其种群能达到第三层林木的空间,是一种稳定型的连续型构造种群;在单层林内,一般退居到灌木层,是一种增长型的连续型构造种群,但上层消失,其种群也消失。一般100m²有7m以下各级个体25~30株,成团分布.从幼苗到小树存活率6.67%~9.09%。其种群表现出生态型和生态体型的变异。

Abstract:

Twenty-three species of Camellia sect.nitidissima are all evergreen broad-leaved microphanerophyte,and are the population of the monsoon forest or ravine forest of Guangxi.They are distributed in ravine,along mountain brook,circular low-lying land and on slope with higher moisture and shade degree. The intensity of illumination is usually 320 to 600 Lux,and the relative air humidity is from 77% to 94% in forest.On karst landform,the contents of ash and calcium element in the leaves of the population of 13 species are respectively from 0.8 tol and from 3 to 5 times higher than 7 species on erosional landform. The population of Camellia impressinervis,C.nitidissima,C.tunghinensis and C.euphlebia require the highest humidity in the 23 species.C.parvipetala is more drought-resistant.The population of Camellia sect.nitidissima are usually able to get into the space of third sublevel of tree in mature community,and it is a stable and consecutive structural population type.In single-storeyed forest,they usually fall back to shrub layer, and it is a increasing and consecutive structural population type,but if the overwoods disappear,they will vanish.Usually,there are 25 to 30 of the various scales individuals under 7 metres hight in each 100m² sample plot. They always appear in clumped disposal.The survival rate of population from seedling to young tree is from 6.67% to 9.09%.These populations also exhibit the variation of ecotype and ecophene.