Study On Sprout Regeneration Of Mytilaria Laosensis Plantation

Mytilaria laosensis is a fast-growing tree species in southern China;it has strong capacity of coppice regeneration.For a long time,we used seedlings for planting new forests in China,which was costly and might cause erosion problems.Nowadays,the objective of forest management is changed from the high cost,high production but low benefit way to a comprehensive way achieving economic,ecological and environmental benefits.Coppice regeneration is one of the approaches which can reduce the planting cost,and avoid the problems caused by land preparation.However,there is little research about coppice regeneration of Mytilaria laosensis plantation.The thesis studied the first coppice regeneration of Mytilaria laosensis plantation,focusing on a comparative test between seedling planting and coppice regeneration,the effect of burning on coppice plantation,and the effect of coppice shoots on the regeneration.The results show that:(1)Bycomparison of the number and the growth of the coppice shoot on 4 different diameterrangestump.The number of coppice shoot is largest,and the growth of coppice shoot is beston 20-25cmstump.(2)Through comparing the numberand the growth of the coppice shoot on5different heightstump,the stump close to the ground had the largest number and the best growth coppice shootwith respect to other height of stump.(3)Through the comparative test between seedling planting and coppice regeneration,results showed that the BDH,height,crown,stem straightness and biomass of the coppice regeneration was significantly higher than those of the seedling planting forest.Therefore,we suggest strongly that coppice regeneration rather than seedling planting,especially on a Mytilaria laosensis cut-over land.(4)We studied the number of coppice shoots on the cut-over stem and found that,keeping one sprout achieved the best in DBH and height.As the number of coppice shoots increased,the growth of DBH and height reduced.In practice,we recommend keeping two sprouts in case of man-made destruction or natural disasters(e.g.wind,storm).(5)A burning test on a Mytilaria laosensis cut-over land showed that,there is no significant effect on the BDH,height,crown and biomass of the coppice regeneration between BURN and NO BURN lands.However,burning has bad effects on erosions,nutrients and environments,we suggest NO BURN on Mytilaria laosensis cut-over land.