崇明东滩围垦芦苇生长、繁殖和生物量分配对大气温度升高的响应

应用开顶式生长室(OTCs)模拟增温试验，研究了上海市崇明岛东滩湿地围垦区芦苇的生长、繁殖和生物量分配对温度升高的响应。结果表明：温度升高使株高显著增加，但对茎粗的影响不明显。与对照相比，升温显著增加了叶长、叶宽、叶面积；但却显著减少了叶面积比率(LAR)和比叶面积(SLA)，对叶长/叶宽，叶质比(LMR)无显著影响。研究发现，升温使开花个体数、开花率、花序高、花颈长、花数以及种子数量均显著减少，对芦苇的繁殖起到抑制作用。此外，升温时地上部分各层生物量显著增加，而且从下到上增加程度逐渐增大；根、茎、叶的生物量显著增加；花的生物量显著减少。升温对根各层生物量影响不同，上层生物量显著增加，中层显著减少，下层变化不明显。进一步研究表明，升温使根和花生物量占总生物量的比例显著下降，茎和叶生物量所占比例显著升高。

EFFECTS OF ATMOSPHERIC ELEVATED TEMPERATURE ON THE GROWTH, REPRODUCTION AND BIOMASS ALLOCATION OF RECLAMATION PHRAGMITES AUSTRALIS IN EAST BEACH OF CHONGMING ISLAND〖

A total number of 8 open top chamber (OTC) experiments were carried out in East Beach of Chongming Island of Shanghai in March 2008.The effects of elevated temperature (ET) on the growth,reproduction and biomass allocation of reclamation Phragmites australis were examined in November 2008.The results showed that plant height increased significantly,but the stem diameter did not change significantly in response to the ET.Leaf length,leaf width and leaf area increased significantly,the leaf length width ratio and the leaf mass ratio (LMR) did not change significantly,and the leaf area ratio (LAR),the specific leaf area (SLA) decreased significantly under the ET compared with the control.We found that the individual number of flower,flowering rate,height of inflorescence,length of flower stalk,flower number and seed number deceased significantly under ET.Meanwhile,the ET inhibited 〖WTBX〗P.australis reproduction.In addition,the biomass of different layers in aerial part,root,stem and leaf increased significantly,but the biomass of flower reduced significantly under the ET.But the effects of the ET on the biomass of different layers of root were different.The biomass of upper layer increased significantly,the middle layer decreased significantly,and the lower layer did not change significantly.We further found that the proportion root biomass and flower biomass decreased significantly,but the proportion of stem biomass and leaf biomass rose significantly under the ET.