【作者】 朱琼琼；

【导师】 鲁长虎；

【作者基本信息】 南京林业大学 ， 野生动植物保护与利用， 2007， 硕士

【摘要】 本文以迁地状态下和原生状态下的不同红豆杉(Taxus)种群做为研究对象，通过调查红豆杉天然更新种群的分布格局、观察鸟类取食红豆杉种子行为、记录红豆杉落果命运，分析和阐明了食果鸟类在红豆杉种群天然更新过程中的作用。中山植物园的红豆杉天然更新种群分布于距母树10m以外的坡上，共统计幼树和幼苗213棵，主要分布于中下坡，空间格局符合聚集分布特征，种群为纺锤形结构，存活曲线呈凸型，为衰退型种群。仙寓山的天然更新种群共统计幼树和幼苗1329棵，其中母树下更新有一定数量的实生苗，但存活率几为零，幼苗和幼树主要分布于中下坡，空间格局为聚集分布，种群为金字塔结构，存活曲线为典型的凹型，为增长型种群。红豆杉“果实”成熟后，除了一小部分掉落母树下，主要被鸟类直接在树上取食。食果鸟类整吞“果实”，消化果肉(假种皮)后，种子经消化道随粪便排出，以此过程传播种子。经过对结实母树的定点、连续观察，在中山植物园共记录到7种鸟类取食红豆杉“果实”，以红嘴蓝鹊(Urocissa erythrorhyncha)、白头鹎(Pycnonotus sinensis)、灰喜鹊(Cyanopica cyana)为主要取食者，根据鸟类的取食路径和取食时在各方向的进出频次分析，确定红嘴蓝鹊为主要传播者；仙寓山共记录到8种鸟类，主要取食者和传播者为红嘴蓝鹊、栗背短脚鹎(Hemixos castanonotus)、绿翅短脚鹎(Hypsipetes mcclellandii)。食果鸟类对红豆杉天然种群的更新意义如下：(1)通过取食，将种子传播至新的生挠，对种群扩散、占据新的生境具有重要意义；(2)这种传播往往将种子散布至种子成活率特别高的地方，在中山植物园中，红嘴蓝鹊取食后多飞向对面的坡上，而坡上有一定的阴蔽、土壤湿润、排水良好这些都能满足红豆杉的萌发和生长，使得迁地状态下的红豆杉种群得到更新扩散；(3)这种远距离的鸟传播方式，减少了种子和幼苗的竞争和死亡，在仙寓山，由于母株附近由于刻度竞争的影响，种子和幼苗的死亡率都较高，通过鸟类取食传播扩散，减少了幼苗间的竞争，提高了幼苗存活率。更多还原

【Abstract】 Field work was carried out in Nanjing Botanical Garden Mem. Sun Yat-Sen and Xianyu Mountain in Anhui province. The spatial pattern of yews’ population, fruit drop fate, frugivorus birds’ preying behaviour were studied. In Botanical Garden Mere. Sun Yat-Sen, there was no seedlings or younglings under the parent trees, and all 213 younglings and seedlings were found on the hillside which was about 10m away from the parent trees. The younglings and seedlings distributed on the mesoslope and downgrade principally, the characteristic of spatial pattern was clumped, and the population’s survival curve was Deevey I type, and its age structure was declining. There were 1329 younglings and seedlings found on the hillside, including some seedlings under the parent tree. The characteristic of spatial pattern was clumped, and the population’s survival curve was DeeveyⅡtype, and its age structure was increasing. When the fruits were ripen, they principally eaten by frugivorus birds. They mostly devoured the whole fruit, and digested the red aril, then defecated the seed. There were seven frugivorus birds preying yew’s fruits in Nanjing Botanical Garden Mem. Sun Yat-Sen, of which the Red-billed Blue Magpie (Urocissa erythrorhyncha), Light-vented Bulbul (Pycnonotus sinensis) and Azure-winged Magpie (Cyanopica cyana) were the most important predators, and the Red-billed Blue Magpie was the disperser. There were eight frugivorus birds preying yew’s fruits in Xianyu Mountain, of which the Red-billed Blue Magpie, Chestnut Bulbul (Hemixos castanonotus) and Mountain Bulbul(Hypsipetes mcclellandii) were the most important predators and dispersers. Frugivorus birds play an important role in yews regeneration, first they dispersed the yew’s seeds which had advantages to yew’s population to colonize new habitat patches. Second frugivorus birds often distribute the seeds to the site which is adequate for germination and survival, and in our investigation the Red-billed Blue Magpie often dispersed yew’s seeds to the hillside in Botanical Garden Mere. Sun Yat-Sen, on which the circumstance is beneficial for yews to germinate and survive. Third in our investigation the seedlings near around parent tree showed higher mortality rate in Xianyu Mountain, and the seed dispersal by frugivorus birds was declining the density-depedent of the seedings and youngling and improve the livability.更多还原