Analysis And Technology Application Of Phyllostachys Heterocycla Cv.pubescens Crown Structure

Phyllostachys heterocycla cv.pubescens is the most widely planted bamboo species with the highest economic and ecological benefit,which plays a very important role in the development of bamboo industry in our country.The experimental ground is located in Suichang,Longquan and the area is about600m2,We measured diameter at breast height,height,crown length,crown width and branch length of Phyllostachys heterocycla cv.pubescens,then use path analysis and regression analysis to study.the results showed that:1.Length of bamboo's long and short branch in different canopy has same distribution regularity,it is longer at the bottom of the canopy,and be the longest at the 2/6 canopy,then decreases with the increase of canopy until at the top of the canopy.Average length of long and short branch in different canopy increases with the increase of diameter at breast height(DBH),and it increases rapidly in small diameter(7?DBH<11cm),slowly in large diameter(DBH?11cm).Age has small influence on branch length.2.Angle of branch becomes largest at the bottom of the canopy,and decreases with the increase of canopy height until at the top of the canopy,then decreases slowly with the increase of canopy height.Angle of branch from 1/6 to 4/6 canopy decreases with the increase of diameter at breast height(DBH),and it decreases rapidly in small diameter(7 ? DBH<11cm),slowly in large diameter(DBH ? 11cm);Angle of branch at 5/6 canopy increases with the increase of diameter at breast height(DBH)in small diameter(7?DBH<11cm),then decreases.Age has small influence on angle of branch.3.The equation which show the best allometric growth relationship between diameter at breast height(DBH)and crown length(CL),diameter at breast height(DBH)and crown width(CW),diameter at breast height(DBH)and volume of crown(VC)is power-function equation,and the coefficient of determination of DBH and VC is the largest,it is 0.401.4.I(high density),II(medium density),III(low density)have no influence on crown width(CW),length and angle of branch,the height of CL and volume of crown(VC)decrease with the increase of densities.The height of CL increases fastest in I(high density),then followed by II(medium density),III(low density);Size of CW and VC increases fastest in III(low density),then followed by II(medium density),I(high density).CL in high density influences VC more than DBH,and in contrast with the decrease of density.5.Average height(H),crown length(CL)and crown width(CW)decreases with altitude(300,600,900)increasing,average volume of crown(VC)increases with altitude(300,600,900)increasing,and the range of CW and VC increases with altitude increasing.Crown ratio has different distribution in different altitude,it means that the relationship of CL and H is changing with altitude increasing.6.CL at low altitude(300m)influence CW(crown width)and crown ratio more than DBH.But DBH at altitude(600m,900m)influence CW and crown ratio more than CL;CL at three altitude influence VC more than DBH.