无瓣海桑幼苗对不同遮光度的生理生态响应  

Eco-physiological responses of Sonnerratia apetala seedlings to different levels of shading

作　　者：刁俊明[1] 曾宪录[1] 陈桂珠[2] 

机构地区：[1]嘉应学院生命科学学院,广东梅州514010 [2]中山大学环境科学与工程学院,广州510275

出　　处：《生态学杂志》2010年第7期1289-1294,共6页Chinese Journal of Ecology

基　　金：联合国环境规划署/全球环境基金项目(GF/2730-02-4340);广东省科技计划资助项目(2009198)

摘　　要：依据实地测定人工无瓣海桑红树林不同环境下的光照强度,研究了无瓣海桑幼苗在不同遮光度环境中的生理生态响应。结果表明,随着遮光度的增大,无瓣海桑的种子萌发、幼苗的生理生态指标水平均呈下降趋势。在80%和40%全光照下,幼苗的茎高、基径、节数和叶片数下降。当光强为全光照的20%即遮光过度时,幼苗就表现出生长严重受阻的响应。弱光环境下无瓣海桑种子的发芽率很低,无瓣海桑幼苗叶片的叶绿素含量、净光合速率、可溶性总糖含量和硝酸还原酶活性等生理参数均呈下降趋势,且各处理间差异显著。试验表明,弱光条件是造成无瓣海桑幼苗生理指标水平低下和死亡率较高的主要原因,并对无瓣海桑的天然更新与自然扩散和人工造林技术进行了讨论。An in situ measurement of light intensity was conducted in the Sonnerratia apetala plantations under different environmental conditions,and the eco-physiological responses of the S.apetala seedlings to different light intensities were studied.The seed germination rate and the seedling’s eco-physiological parameters of S.apetala all decreased with the increasing level of shading.At 80% and 40% of full light,the stem height,basal diameter,node number,and lamina number of seedlings decreased to some extent;while at 20% of full light,the seedling’s growth was seriously restricted.At weak light intensity,the germination rate was very low,and the eco-physiological parameters such as chlorophyll content,net photosynthetic rate,soluble sugar contents,and nitrate reductase activity decreased,with significant differences to those at strong light intensity.Therefore,low light intensity could be the main reason for the low level eco-physiological parameters and high death rate of S.apetala seedlings.The natural regeneration and dispersal of S.apetala and the techniques for S.apetala forestation were also discussed.

关 键 词：无瓣海桑 遮光环境 生理响应 自然扩散 

分 类 号：Q945[生物学—植物学]