济源太行山区鼠类对三种林木种子的扩散和贮藏

Seed dispersal and hoarding of three species by rodents in the Mt. Taihangshan Area, Jiyuan,China

对取食种子的动物而言,种子的选择、扩散以及随后的处理是一个复杂的过程。为了解济源太行山区鼠类对不同种林木种子的选择和扩散策略的差异,于2011年9月10日至11月8日,选取山杏、桃和栓皮栎3种林木种子,将种子标记后,释放于次生林中,以5d间隔,调查并记录种子命运。结果表明:(1)大林姬鼠和岩松鼠是该地区主要的种子取食者和扩散者;(2)3种种子的扩散速率明显不同,栓皮栎种子扩散速率最快(中位存留时间8.6d),其次为山杏种子(中位存留时间20.9d),桃种子扩散速率最慢(中位存留时间37.5d);(3)鼠类倾向于取食栓皮栎种子(55.0%),埋藏山杏种子(62.0%),但忽略桃种子(原地存留率99.0%);(4)88.6%的山杏和78.8%的栓皮栎种子被贮藏在灌丛下方、树干基部周围和石块旁边等生境中,而仅有4.3%的山杏和9.1%的栓皮栎种子被贮藏于裸地中;(5)鼠类将山杏种子搬运到更远(3.4±2.1m,mean±SE,n=63)处贮藏;而栓皮栎种子的搬运距离则相对较近(2.5±2.4m,n=57)。结果显示:鼠类对不同种植物种子具有明显的取食、贮藏偏好和不同的贮藏策略。

Seed hoarders, such as small rodents, may adopt different eating and hoarding strategies for seeds of different plant species, and resulting in different plant seed dispersal patterns. At here, we tracked the seeds of three sympatric tree species ： Quercus variabilis, Prunus armeniaca, Prunus persica, dispersed by small rodents in the Yugong State-owned For- estry Station, Jiyuan, Henan Province, Mt. Taihangshan area from September lOth to November 8th in 2011. We aimed to determine differences in harvest rates, seed fates, dispersal distances, cache sites and cache size among these seeds and understand the influence of rodents on seed dispersal of these sympatric tree species. The results showed that： 1 ） Apode- mus peninsulae and Sciurotamias davidianus were mainly responsible for the consumption and hoarding of the tested seeds; 2） Seed harvest rates varied significantly among different seed species, Q. variabilis （ median survival times （MST） ： 8.6 d） 〉P. armeniaca （MST： 20.9 d） 〉 P. persica （MST： 37.5 d） ; 3） A total of 55.0 % of Q. variabilis acorns were consumed, 62. 0 % of P. armeniaca seeds were scatter-hoarded （ buried in soil）, whereas almost all of P. persica seeds （99. 0 % ） remained in situ; 4） Majorities seeds of P. armeniaca （88, 6% ） and Q. variabilis （78.9%） were hoarded either under shrubs, near the tree stems or near rock edges, whereas a few seeds of P. armeniaca （4. 3% ） and Q. variabilis （9. 1% ） were hoarded in the microhabitat of bare ground ; 5 ） P. armeniaca seeds were dispersed farther from the seed sources （3.4 ± 2. 1 m, mean ＋ SE, n = 63 ） than were Q. variabilis acorns （2. 5±2.4 m, n = 57）. These results suggest that small rodents are likely to adopt different hoarding strategies for sympatric plant seeds, and subsequently result in different plant seed dispersal patterns.