Population Ecology Of Abies Fargesii In Shennongjia Area

The dissertation focuses on characteristics of population of Abies fargesii in Shennongjia Natural Nature Reserve. Abies fargesii, an evergreen arbor endemic to China, is an important forest species in Qinling mountain and Bashan mountain. The studies primarily deal with population ecology of this species, including community structure, population structure and dynamics, distribution pattern of main species of the community, etc. in order to provide theoretic evidence for culturing and protecting Abies fargesii forest.The Abies fargesii forest was typical temperate evergreen coniferous forest. Abies fargesii was the outstanding dominant species in the community, especially in the tree layer, its importance value reached 54.30%. The appearance of the communities was characterized by the evergreen coniferous microphyll with coriaceous phanerophytes. There were 74 species of vascular plants belonging to 63 genera and 34 families in the plot of 1.0 hm2. The floral composition could be divided into 12 areal-types and 3 subtypes, and the temperate elements took a major part. The structure of the community was integrated with obvious tree layer, shrub layer, herb layer and developed moss layer. Herb layer comprised abundant plant species, while majority of them belonged to Compositae, there were also many species of Oxalidaceae and Polygonaceae.The Abies fargesii population was plentiful in seedlings, which accounted for 90.4%, while there were only 5 saplings above 3 m high. Strong competition of light resource caused many saplings died. It was found that saplings were established more frequently in the gap than under the close canopy, which indicated a pattern of gap...