关键词: 山地, 冠层光合作用, 净生态系统交换, 辐射表, 坡面平行安装, 直角双曲线

Abstract: During the process of sexual reproduction of plants, volatile compounds emitted by flowers play an important role in attracting pollinators who prompt pollination and fertilization of flowers. Amomum villosum is one of the four most famous traditional medicines in south China. The low set rate is the bottleneck of production of A. villosum. Here, the head space dynamic method was used to collect the floral scents from A. villosum before and after pollination. The chemical compositions were analyzed and identified by gas chromatography and mass spectrometry (GC-MS). The results showed that total 22 volatile compounds were found from the floral scents before and after pollination, which were mainly classified into aliphatic, terpenoids and aromatic compounds. The components of volatiles obviously differed before and after pollination. Compared with floral scents before pollination, seven chemical compounds (isopropymyristate, diethyl phthalate, nonanal, bicyclogermacrene, 2,3-dihydro-4-methyl, α-farnesene and tridecane) disappeared, while γ-elemene, β-phellandrene, D-limonene, α-pinene and 2-undecanone compound decreased after pollination. Three chemical compounds \[2-cyclohexen-1-one, 2-methyl-5-(1-methylethenyl), 1,6-octadien-3-ol,3,7-dimethyl, and bicyclo \[3.1.0\] hexane 4-methylene-1-(1-methylethyl)\] newly appeared, and benzoic acid, hexyl ester, β-myrcene, butylated hydroxytoluene and undecane, 4,7dimethyl increased after pollination. These compounds with dramatical changes before and after pollination should be the main active compounds causing the pollinator’s behavioral response. The flowers of A. villosumreleased multiple chemical compounds with different component ratios to attract potential pollinators, which performed the chemical communication of “generalization” strategy. Furthermore, screening active compounds that can effectively attract pollinators may improve the pollination and seed production ofA. villosum.

Key words: canopy photosynthesis, montane, rectangular hyperbola function, net ecosystem exchange, radiometer, slope-parallel installation