浙江天童山鼠类对栲树种子的捕食和扩散

在浙江天童山国家森林公园,研究了鼠类在常绿阔叶林、马尾松林和灌丛几种生境内对栲树（Castanopsis fargesii）种子的捕食和扩散的影响.结果表明,社鼠（Niviventer confucianus）和针毛鼠（N.fulvescens）是栲树种子的主要捕食者.种子在刚布下后的几天内消失的最快,随后其日消失率便逐渐降低,在不同生境中,其日消失率也有所不同,在灌丛中日消失率最高（7.54%）,其次是马尾松林（7.29%）,而常绿阔叶林中3条样带的日消失率较低.在损失的种子中,各种种子命运所占比例在样带中存在着差异,灌丛中失踪的种子比例最高,占97.77%,而样带2的则最低,只占8.91%.这与不同样带中的植被组成密切相关.同时,鼠类对栲树种子扩散的距离比较近,观察到的最远扩散距离为12.7 m.

Seed predation and dispersal of Castanopsis fargesii by rodents in Tiantong Mountain, Zhejiang Province

This paper studied the effects of rodents on the seed predation and dispersal of Castanopsis fargesii in Tiantong Mountain,a National Forest Park in Ningbo City of Zhejiang Province.In this Mountain,evergreen broad-leaved forest is the major forest type,while C.fargesii is the dominant species.For seed release,five transects are located in three types of habitats: three in evergreen broadleaved forest,and other two in Pinus massoniana forest and shrub land,respectively.The results showed that rodents Niviventer confucianus and Niviventer fulvescens were the main seed predators.The loss rate of C.fargesii seed was high during the beginning of observation period,and then decreased gradually.The daily seed disappearance rate(DSDR) varied in different habitats,which was the highest(7.54%) in shrub land,and the lowest(4.47%) in evergreen broad-leaved forest.Among the lost seeds,three categories of their fate were defined:(1) the seeds were consumed by rodents,and the fragments of the seeds were within the tags;(2) the seeds were cut from the tags by rodents,and their fate was unknown;(3) both the seed and the tag disappeared.The proportion of the three categories in these habitats was differed.In shrub land,the third category was the highest(97.77%),while at the second transect of evergreen broad-leaved forest,it was the lowest(8.91%).The difference was related to the vegetation composition and density in the habitats.The dispersal distance of the seeds by rodents was quite short,with the maximum of 12.7 m.