鸟类对山黄麻种子的传播及其生态作用

在云南西双版纳的勐宋和勐仑地区观察和研究了传统山黄麻种子的鸟类。在野外持网捕获摄食山黄麻果实的鸟类，称量后分别放在布袋内，让其自然排泄，然后标志释放，观察和网捕共记录到摄食山黄麻果实的鸟类36种，其中26种挂网捕获并从排泄物得到种子。用鸟类排泄物中的山黄麻种子、山黄麻树上采摘的成熟果实及人工分离山黄麻种子播种，进行萌发对比实验，实验结果表明，直接播种成熟果实，在阳光充足的空旷地、林冠下或用树叶覆盖遮光等条件下都未萌发，种子容易霉烂或被虫蚀；从山黄麻果肉中分离出来的种子具有萌发能力；而经鸟类摄食、消化后从果肉中分离的种子，具有较好的萌发活力。在不同条件下山黄麻种子萌发情况差异明显，林冠下条件对种子有抑制作用，阳光作用下种子显示出很好的萌发及成活率。鸟类排泄物种子放在林上或用树叶覆盖遮光，经过较长时间便可萌发，而人工分离种子不能萌发。鸟类摄食及消化过程对山黄麻种子的处理表现出很好的生态互惠关系，观察萌发后的山黄麻幼苗的生长情况还表明，幼苗生长也需要光照和较开阔的生境条件，鸟类取食山黄麻果实及其将种子远距离传播适宜生境，正好具有这样的生态作用。

Trema orientalis Seeds Dispersed by Birds and Its Ecological Role

Trema orientalis seeds dispersing by birds were studied at Mengsong and Menglun areas, Xishuangbanna, Yunnan Province. It was observed and recorded that species of birds eating T.orientalis fruits in the field. Different types of mist nets were employed at forest edges and gapes, as well as near the ripe fruit trees. Birds to eat the T.orientalis fruits were mist netted in field, each bird was placed in a separate cloth bag, its excreted feces was collected, and the seeds in bird feces were checkuped. 36 species of birds have been recorded to consume the T.orientalis fruits, and fecal samples from 26 species by mist netted were gotten. Germinating experiments were conducted through sowing a kind of ripe fruit and two kind of seeds of T.orientalis in 4 conditions. The ripe fruits of T.orientalis were directly sowed, they could not germinate and were easily decay. The seeds separated by handwork from the fruits could germinate. The seeds excreted by nature from birds had a very high rate of germination. It is suggested that the seeds had changed from dormancy into activity while the T.orientalis fruits consumed by the birds. Birds took the seeds to the forest edges and newly cut areas that more suitable for germination and seedling growth. There are ecology reciprocal role between birds and T.orientalis .