Crown biomass and increment in mid-young-aged Pinus elliottii plantation from Qianyanzhou

To increase future forest research efficiency and management,a model of branch biomass and growth increment for mid-young-aged Pinus elliottii was determined.Estimates were made using the branch analysis method with regression models of crown biomass and increment-established.Results showed a significant power correlation existed between branch biomass(WB) and branch diameter(DB)(WB=0.017 8 D3.006 1B) with r2=0.840 8(P0.01).Correlation between area of the total branch section(ATB) and diameter at breast height(DBH) was well fitted by ATB=1.850 2 D1.541 8BH with r2=0.750 9(P0.01).A significant power correlation also existed between crown biomass(WC) and DBH(WC=7.105 9 D2.596 5BH) with r2=0.920 5(P0.01).Parameter evaluation and group test results showed that the crown biomass model could satisfy the practical requirements well with a prediction exactness of about 90% and with the total relative standard error within permitted limits.Correlation between crown increment(y) and DBH increment(x) was also well fitted by y=29.354 1x0.255 4 with r2=0.956 6(P0.01).[Ch,3 fig.1 tab.23 ref.]