米老排林下黄藤的生长表现和光合特征

Growth Performance and Photosynthesis of Daemonorops margaritae planted in a Mytilaria laosensis plantation

米老排林下种植6年的黄藤主茎长为0.28±0.04 m,产生萌茎的植株占48%,平均拥有萌茎1.3±0.2条,远远低于相邻间伐50%的马尾松林下的黄藤;黄藤植株晴天全天得到的有效光合辐射和相应的净光合速率最高为0.6μmol.m-2.s-1和0.05μmol CO2.m-2.s-1,远远低于空旷地上的1 539μmol.m-2.s-1和3.11μmol CO2.m-2.s-1,表明米老排林下黄藤生长缓慢,可能与其得到的有效光合辐射较低有关,若在米老林下间种黄藤需进行间伐以增加透光。

Growth performance and photosynthesis were determined for Daemonorops margaritae at 6 years after planting in a plantation of Mytilaria laosensis. Its stem length was 0.28 ±0.04 m, ca. 5 m shorter than that in a plantation of Pinus massoniana. The net photosynthesis rate was highest at 3.11 μmol CO2· m^-2 · s^-1 when leaves were lighted with a 1500 μmol · m^-2 · s^-1 of photosynthetically active radiation （PAR）. However, the PAR and the net photosynthetic rate in a sunny winter day were low for D. margaritae, ranging from 0 to 0.6 μmol·m^-2·s^-1 and - 1.1 to 0.05 μmol CO2 · m ^-2· s^-1 , respectively. It was concluded that the canopy of the planta- tion of M. laosensis shaded too much light for D. margaritae, therefore D. margaritae should be not planted in a plantation of M. laosensis if cane production was targeted.