Primary Research On The Soil Seed Bank And The Distribution Of Young Seedlings Of Semi-tropical Evergreen-broadleaf Forests In Southwest Edge Of Sichuan Basin

The soil seed banks, seed rain and seedlings are the main constructive parts of the forestry eco-system, which make an indispensable part to the vegetation regeneration, succession and diffusion., playing a very important role for human's learning more about the natural regeneration ability and approach .However, there are few semi-tropical evergreen- broadleaf forests existing nowadays in china caused by the human's disruption .Hence ,to quest for the succession dynamics and the stability of semi-tropical evergreen-broadleaf forests are the keystone for the protection of natural forestry. Muchuan semi-tropical evergreen-broad leaf forests as one of the well-protected secondary evergreen forests were studied in this article. The study of its soil seed banks, seed rain and the distribution of the seedlings is to investigate the constitution of its soil seed bank, density and fate, furthermore, the obstructive factors influencing the forests and the direction of natural forest regeneration, which all can be used as the reference for the protection of natural forests in the similar areas and the establishment of regeneration countermeasure.Field investigation, germination in the greenhouse and physical separation methods were used to research the soil seed bank, seed rain and the distribution of the seedlings .the result shows:1. The plantation of the sites are the typical semi-tropical evergreen-broadleaf forests community, the species of vegetation are abundant and flourished. Reproducing species input an average of 261.2-ind/ m~2 to the soil seed bank every year in seed rain, the viable seeds contributing to community regeneration were 142.3 ind/ m~2. The density of the seed banks including 22 leading species arranges 692.8ind/m~2~929.2ind...