摘要
近年来,河岸带植被的分布及其生物多样性的维持机制成为研究热点,然而目前对河岸带雌雄异株濒危植物的生态适应机制的研究较少。以河岸带专性濒危树种连香树(Cercidiphyllum japonicum)为研究对象,比较不同河岸距离下雌雄植株的数量、形态、叶片N、P重吸收效率及土壤水分、全N、全P的差异及相关性。结果表明:河距的增加显著降低了雌株的数量,而对雄株的数量影响不大,进而降低了种群的性比(雌/雄)。离河岸带远的地方,连香树种群性比显著偏雄(雌雄性比为0.289;χ^(2)=4.57,P<0.05),且雄株株高、成熟叶N含量、叶P重吸收效率均显著高于雌株,而在距河岸近的地方以上指标在性别间均无显著差异。雄株叶N重吸收效率、雌株的叶P重吸收效率与其叶片养分、土壤因子相关性较强。且连香树(尤其是雌株)的株高与叶片N、P重吸收效率均呈显著正相关。这些结果表明,连香树对河距的适应性响应具有性别差异,且雌雄植株叶片的N和P重吸收效率对其植物、土壤因子的响应不同。雌株对河岸生境的依赖可能限定了该种群的分布。
Vegetation distribution and biodiversity maintain in riparian zone have been a hot topic recently,however,few studies have been conducted on the ecological adaptation of the endangered riparian dioecioustrees.We explored the sex-related difference of Cercidiphyllum japonicum adults in number,morphology,leafnitrogen(NRE)-and phosphorus-(PRE)resorption efficiencies,soil contents of water,nitrogen and phosphorusand the relationships of NRE or PRE with leaf N and P,soil contents of water,N and P or plant morphology.The number of females significantly decreased rather than males with increasing distance to riverside,resultingin a decrease in the sex ratio(females/males).In long distance,the sex ratio was significantly male-biased(female/male=0.289;χ^(2)=4.57,P<0.05),N content of green leaves and PRE of males were higher than that ofmales,while these traits were similar both sexes near riverside.In addition,male NRE or female PRE wasrelated to green leaf,soil water and nutrient,and height of C.japonicum(especially for males)were positivewith NRE and PRE.Our results showed that there were sex-specific adaptive responses to river distance in C.japonicum,and female and male leaf NRE and PRE differently respond to leaf nutrient or soil factors.Therequirement of near riparian habitat for females might limit its population distribution.
作者
黄雪梅
马永红
董廷发
HUANG Xue-Mei;MA Yong-Hong;DONG Ting-Fa(Key Laboratory of Southwest China Wildlife Resources Conservation,Ministry of Education,Institute of Plant Adaptation and Utilization in Southwest Mountains,College of Life Sciences,China West Normal University,Nanchong 637009)
出处
《植物研究》
CAS
CSCD
北大核心
2021年第5期789-797,共9页
Bulletin of Botanical Research
基金
西华师范大学英才基金(17YC323,17YC339)。
关键词
雌雄异株
河岸带
濒危植物
养分重吸收效率
dioecy
riparian zone
endangered plants
nutrient resorption efficiency