The Research On Growth Law And Productivity Of Cyclobalanopsis Glauca

Cyclobalanopsis glauca is China's precious timber and landscape trees.Its wood material is hard,structure,and has the ability to purify the air,inhibit harmful substances,suitable for cultivation and management in the subtropical regions of china.But the current domestic Research on productivity and growth law of Cyclobalanopsis glauca is less studied,the lack of theory to guide the cultivation of Cyclobalanopsis glauca plantation,so in order to fill this gap,find the best mode of cultivation technology of artificial Cyclobalanopsis glauca,now in Meihua village,Daoxian County,Yongzhou city,Hunan province,take the 50a Cyclobalanopsis glauca plantations as the object,based on standard survey,study its growth law,plantation biomass and productivity.The results are as follows:(1)50a of the total growth of Cyclobalanopsis glauca,tree height,DBH and volume were increased with age growth.In section 50a,tree height growth,DBH growth and the total volume and growth increment of Cyclobalanopsis glauca were 12.4m,17.00cm and 0.3260m3.In 50a,the average tree height growth of Cyclobalanopsis glauca was first increased and then decreased in the range of 0.28m?0.4m,the 15a reached the peak;the average growth of DBH of Cyclobalanopsis glauca is first increased and then decreased in the range of 0.29cm?0.44cm,the 20a reached the peak;the average growth of Cyclobalanopsis glauca has been slowly rising,reaching 50a 0.0065m3/a.Successive growth of Cyclobalanopsis glauca high first increased and then decreased in the range of 0.15m?0.45m,the 12a reached the peak;successive growth diameter is increased first and then decreased,the range is 0.09cm-0.56cm,the 15a reached the peak;annual growth volume is increased first and then decreased,1he range is 0V0004m3?0.0100m3,the 40a reached the peak.Successive growth of Cyclobalanopsis glauca volume and average growth in the intersection of 50a,said the number of Cyclobalanopsis glauca plantations reached maturity in volume,can determine the Cyclobalanopsis glauca plantations the felling age is 50a.(2)The growth of Cyclobalanopsis glauca regression equation fitting,The regression model of tree height at breast height is optimal in the Korf model,The regression model of DBH at breast height is optimal in the Richard model,The regression model of volume at breast height is optimal in the Gompertz model.The correlation coefficient R2 of the 3 optimal models are all above 0.999,and the Residual sum of squares is very small.The model has high precision and can be used in production practice.(3)The average biomass per individual was 936.22kg in 50-year-old Cyclobalanopsis glauca plantation.The aboveground biomass and underground biomass were 757.18kg and 179.04kg,aboveground biomass accounting for 80.88%of individual total biomass.Plant biomass of Cyclobalanopsis glauca were arranged from large to small:trank,limb,Root skeleton,bark,leaf,coarse root,medium root and fine root;the largest of these is the trunk,the total biomass ratio was 45.60%,secondly limb accounted for 27.14%,the smallest is fine,accounted for only 0.29%.(4)The total biomass of Cyclobalanopsis glauca plantation arbor layer is 595.11 t/hm2,accounting for 98.33%of the total biomass.The aboveground of arbor layer biomass is 481.32t/hm2,accounting for 79.53%of total biomass and The underground of arbor layer biomass is 113.80t/hm2.The biomass of tree layer accounted for the proportion of biomass of tree layer was 45.60%trunk,27.14%limbs,14.33%root stump,4.40%bark,3.74%leaves,3.46%coarse roots,1.04%medium root and 0.29%fine root.Cyclobalanopsis glauca plantation in the lower total biomass is 10.11t/hm2,accounted for 1.67%of forest biomass.(5)The productivity of 50-year-old Cyclobalanopsis glauca plantation is 18.57t · hm-2 · a-1.The order of three different layer:tree layer 15.91t · hm-2 · a-1,shrub layer 1.85t · hm-2 · a-1,herb layer 0.82t · hm-2 · a-1,accounting for 85.65%?9.94%and 4.41%respectively.The productivity of each organ in the arbor layer was:trank 5.43t ·hm-2·a-1(29.22%),leaf 4.45t hm-2a-1(23.97%),branch t hm-2·a-1(17.41%),root t · hm-2 · a-1(12.23%),bark t · hm-2 · a-1(2.81%).