Ecological Studies On Rodent Predating And Dispersing Seeds Of Camellia Pitardii And Dendrobenthamia Hongkongensis In The Forest Of Kuankuoshui Nature Reserve

Many animals, such as birds and rodents, eat and disperse seeds and sarcocarp of plants, which affect the natural regenerate processes of plants. Different animals play different roles in the process and the mutual action among animals affect the renew process of plant community as well. From June to November in 2007, the paper study the dynamic of seed rain and seed bank of Dendrobenthamia hongkongensis and Camellia pitardii , and the influence of rodents eating and dispersing their seeds in the subtropical forest of Kuankuoshui National Reserve of Suiyang county, Guizhou province. At the same time the paper study the potential influence on the seed characteristic of the two kinds of plants due to rodents'choice action. The main results and conclusions are as follows:(1) Seed rain and seed yield are different among different individuals of Dendrobenthamia hongkongensis and Camellia pitardii. Although the huge diversity among different individuals, the rodents eating and dispersing seed is the main influence factor to the fate of the seed in the seed bank.(2)In the research area, the two kinds of animals, rodents and birds, are main animals eating the seeds of Dendrobenthamia hongkongensis and Camellia pitardii. Rattus edwardsi and Rattus fulvesces usually spead seeds in the forest. Leiothrix lutea usually pecks the sarcocarp and plays little role in the spreading seeds process. The behaviors of the rodents collecting and depositing seeds may contribute to the large-scale distribution of Dendrobenthamia hongkongensis and Camellia pitardii.(3) Collecting different size and age fruit at the root, middle and edge of the tree crown of the original arbor woods, Fargesia spathacea Franch and shrubs, the paper study rodents'behavior function of eating and collecting seeds of Dendrobenthamia hongkongensis and Camellia pitardii. The result indicates that the types of seeds Dendrobenthamia hongkongensis and Camellia pitardii collected by rodents are significant different. Rodents are inclined to store nut. The time of Rodents storing the fruit of Dendrobenthamia hongkongensis is shorter than that of the Camellia pitardii. This shows that rodents are inclined to eat flesh fruit as soon as possible and store nut. Rodents took away all placed fruit in less than 10 days. The influence of lack of food and uneven distribution in the forest are bigger than that of the habitat types on the rodents eating seeds.(4) Through observing the fate of the fruit, which marked with metal label, of Dendrobenthamia hongkongensis and Camellia pitardii, the paper discusses whether rodents spread seeds by means of scattered storage seeds. The study imply that rodents deposit dispersedly sarcocarp, after eating, the seeds were spitted near the storage area. Reversely, they deposit nut in a area, namely the crevice of the rock in the forest. The distance between store seeds area and seeds dispersed position is 0.3 to 6.7 meters.In conclusion, rodents not only as predator, but as disseminator, they buried in the superficial soil or under the defoliation to spread seeds, thereby, affect the natural renewed process of plant community.