恐龙河自然保护区元江苏铁种群结构

对恐龙河自然保护区礼社江流域元江苏铁的生境、种群结构调查发现：该保护区内元江苏铁分布于礼社江右岸海拔1100—1400m区域，主要生长在河谷季雨林下，阴坡数量较多，占总株数的92．5％；调查区域元江苏铁种群密度较高，平均11株／100m2；其种群的年龄结构呈金字塔状，Ⅱ龄级苏铁比例最大，占总数的32．94％；由于人为采挖，Ⅳ龄级以上的苏铁数量较少，占到总数的21．57％。目前，该种群面临的威胁主要是人为采挖和生境破坏等，应加大对元江苏铁野生资源的科学、合理保护。

Study on Population Structure of Cycas parvulus in Dinosaur River Nature Reserve

The biotope and population structure of Cycas parvulus in Lishejiang watershed of Dinosaur River Nature Reserve Area in Yunnan Province was surveyed. The results showed that 92.5% of the C. parvulus plants grew on the shady bank of Lishe River under the deciduous seasonal forest at an elevation between 1 100 m and 1 400 m. The population density of C. parvulus was about 11 plants per 100 m2. The age structure of C. parvulus population showed to be in pyramid shape, in which the proportion of II age class was the largest, accounting for 32. 94% of the total. Resulting from human disturbance, the number of the plants older than 1V age class only counted for 21.57% of the total. At present, the C. parvulus population is mainly endangered by human gathering and biotope destruction. It was proposed to reinforce conservation measures in order to protect the C. parvulus re- source scientifically and rationally.