Study On The Effeects Of Controlled Burning On Ecological Process Of Vegetation In Choerospondias Axillaris Plantations

Controlled burning is always used to clean the felling blank of plantation insouth china, but it always causes many environmental problems such as serious soil erosion and ecological environment depravation and so on. Controlled burning is considered as important cause of soil fertility degration of plantation after successive plantings.Choerospondias axillaris is an excellent and fast growing timber tree and share wide management prospect. So research on the influence of controlled burning on ecological process of vegetation in Choerospondias axillaries plantation has both theoretic significance and practical valueThe species composition of controlled burning Choerospondias axillaris plantation and non-burning plantation was analyzed. The results show that the dominant species in shrub layer, herb layer and liana layer were different in the four communities, and the importance value of the same dominant species were different. In the view of species composition, the number of species in the controlled burning Choerospondias axillaris plantation was less than in the non-burning Choerospondias axillaris plantation, and intend to increase with the time, but the increasing extent was different from the non-burning Choerospondias axillaris plantation. Whether three years plantation or six years plantation, the number of family and gena in the controlled burning Choerospondias axillaris plantation was less than in non-burning Choerospondias axillaris plantation and the extent of increasing was less than in non-burning Choerospondias axillaris plantation. All this showed that controlled burning may went against the growth and development of undergrowth. The average individuals of various layer in controlled burning Choerospondias axillaris plantation were less than in non-burning community, but the individual of some shrub species such as Rhus chinensis in the controlled burning Choerospondias axillaris plantation was greater than in non-burning community. Litsea cubeba only appear in the controlled burning Choerospondias axillaris plantation.All this showed that controlled burning may contribute to growth of some species.The a diversity indexes and B diversity indexes were used to study the species diversity of undergrowth plants in the Choerospondias axillaris plantation. The results showed that the species richness of shrub layer, herb layer and liana was less in the controlled burning Choerospondias axillaris plantation than in the non-burning Choerospondias axillaris plantation. In the prophase, the diversity indexes and evenness indexes of shrub layer were greater in the controlled burning Choerospondias axillaris plantation than in the non-burning Choerospondias axillaris plantation, the diversity indexes of the herb layer were less in the controlled burning Choerospondias axillaris plantation than in the non-burning Choerospondias axillaris plantation, the diversity indexes and evenness indexes of liana plant in the controlled burning Choerospondiasaxillaris plantation were also less in the controlled burning Choerospondias axillaris plantation than in the non-burning Choerospondias axillaris plantation. In the anaphase, the diversity indexes and evenness indexes of shrub layer were less in the controlled burning Choerospondias axillaris plantation than in the non-burning Choerospondias axillaris plantation, and the a diversity index of herb layer and liana plant greater in the controlled burning Choerospondias axillaris plantation than in the non-burning Choerospondias axtllaris plantation other than the richness index. In the aspect of dynamics, the increasing extent of a diversity indexes was less in the controlled burning Choerospondias axillaris plantation than in the non-burning Choerospondias axillaris plantation, and the a diversity indexes (except the richness index )of herb layer and liana tended to increase in the controlled burning Choerospondias axillaris plantation whereas the a diversity indexes (except the richness index) of herb layer and liana tended to decrease in the non-burning Choe...