摘要
本文研究了西双版纳热带季节雨林６种树种幼树在林下的光合作用。６种树种的叶单位重量面积（ＳＬＡ）为１６．０２～２８．６７ｍ２ｋｇ－１、光合作用光补偿点（ＰＡＲ）为３．８～６．５μｍｏｌｍ－２ｓ－１、光量子产率为０．０１８～０．０４４、最大净光合速率为１．９７～４．７１μｍｏｌＣＯ２ｍ－２ｓ－１（以单位叶面积表示）和４６．９９～９２．３３μｍｏｌＣＯ２ｋｇ－１ｓ－１（以单位叶干重表示）、暗呼吸速率为０．１５～０．３１μｍｏｌＣＯ２ｍ－２ｓ－１（以单位叶面积表示）和３．６～６．６μｍｏｌＣＯ２ｋｇ－１ｓ－１（以单位叶干重表示）。下层树种细罗伞（Ａｒｄｉｓｉａｔｅｎｅｒａ）的幼树叶片光补偿点、暗呼吸速率和最大净光合作用均为最低，最适应林下荫生环境；中层树种云南玉蕊（Ｂａｒｒｉｎｇｔｏｎｉａｍａｃｒｏｓｔａｃｈｙａ）和小叶藤黄（Ｇａｒｃｉｎｉａｃｏｗａ）的幼树也显示很强的耐荫能力；上层树种网脉核实（Ｄｒｙｐｅｔｅｓｐｅｒｒｅｔｉｃｕｌａｔａ）和中层树种短药蒲桃（Ｓｙｚｙｇｉｕｍｂｒａｃｈｙａｎｔｈｅｒｕｍ）的耐荫能力相对较弱；林冠树种番龙眼（Ｐｏｍｅｔｉａｔｏｍｅｎｔｏｓａ）的幼树以叶干重计算的暗呼吸速率和最大净光合?
Light response of assimilation for six species young trees were measured in the understory of a tropical seasonal rainforest in Xishuangbanna.For the six species,the specific leaf area was from 16.02 to 28.67m 2·kg -1 ,the light compensation from PAR 3.8 to 6.5 μmol·m -2 ·s -1 ,quantum yield from 0 018 to 0 044,maximum net assimilation rate(A max ) from 1 97 to 4 71μmolCO 2·m -2 ·s -1 (per unit leaf area) and from 46 99 to 92 33 μmol CO 2 kg -1 ·s -1 (per unit leaf dry mass),dark respiration rate(Rd) from 0 15 to 0 31 μmolCO 2·m -2 ·s -1 (per unit leaf area) and from 3 6 to 6 6 μmolCO 2·kg -1 ·s -1 (per unit leaf dry mass).The young trees of Ardisia tenera ,the main tree species of the lower layer in the rainforest,were shown to be the most shade tolerant with the lowest light compensation,Rd and A max ;The young trees of Barringtonia macrostachya and Garcinia cowa, the main species of the middle layer,were shown to be very shade tolerant,and the young trees of the upper layer species, Drypetes perreticulata and middle layer species, Syzygium brachyantherum showed relatively weaken shade tolerant ability;for the young trees of canopy species Pometia tomentosa, when A max and Rd expressed on the leaf dry mass,both Rd and A max were very high,the young trees through increase of specific leaf area and decrease of unit leaf area Rd adapted the understory low light environment.
出处
《植物生态学报》
CAS
CSCD
北大核心
1998年第6期499-504,共6页
Chinese Journal of Plant Ecology
基金
中国科学院九五重点项目
中国科学院生态系统研究网络项目资助
