Study On The Biomass Of Mixed Wood At Beigou Forest Land In Hebei Province

Based on secondary mixed needle located north ditch forest farm of mulan forestryadminstration bureau as object, we carried on the the detailed investigation and study aboutthe larch and birch and aspen trees which grows in the sample, and carried on thequantitative analysis to stand structure characteristics, spatial distribution pattern ofbiomass per plant, and so on,which of the north China larch and secondary birch forestand the secondary poplar forest, and carried on the system research for the tree species ofmixed forest biomass change rule. From July2008to June2012, plantation structure, eachorgan biomass percentage of biomass per plant, root ratio, growth rule and regressionmodel of the north China larch and birch and poplar were studied.（1）Through the actual study of sample plot, the types were nine, the density were860plants per hectare. Exist in the current research of mixed needle biomass and totalbiomass of per plant in larch mixed forest change range was3.36to413.90kg, the biomasspercentage for each organ distribution: the average of trunk of58.72%（26.33%72.06%）,the average of dry branches of16.69%（7.14%32.11%）,the mean of root of17.34%（12.04%-12.04%）, the average of leaf of7.24%（2.05%26.27%）. The change range ofbirch whole plant biomass is5.51to586.23kg, the biomass of each organ allocationpercentage: the average of trunk of51.2%（31.1%62.0%）, the average of dry branches of21.0%（16.8%26.5%）, the mean of root of21.8%（17.6%29.3%）, the average of leaf of6.1%（2.0%21.6%）.The change range of aspen total plant biomass was4.1to344.16kg,the biomass percentage for each organ distribution: the average of trunk of63.03%（53.21%69.14%）, the average of dry branches of11.40%（5.26%18.12%）, the mean ofroot of20.12%（16.69%22.67%）, the average of leaf of5.44%（3.42%-8.46%）.The orderfrom big to small of biomass allocation each organ of each tree was stem> root> branch>leaf. The root-shoot rations of larch、birch and aspen which located mixed needle leaf androot respectively that birch is0.281; Larch is0.232; Aspen was0.254.（2）Based on the tree height, diameter at breast height, tree age of Larixprincipis-rupprechtii、birch and aspen in mixed forests were carried on correlation analysisbetween each organ biomass variables, we established the regression model of tree plantsand various organ biomass that D1.3, D2H, tree age （A） as the independent variable, forestplants and various organ biomass per plant as the dependent variable.The optimal model oftree species, respectively:The optimal model for Larix principis-rupprechtii: Dry trunk biomass W=-412.968+22.447（D²H）+0.001（D²H）²（R²=0.988）;Branch branch biomass W=1589.374+0.001+4.01（D²H）（D²H）²（R²=0.935）;The root biomass W=585.523+1.387（D²H）+0.000003526（D²H）²（R²=0.805）;Leaves biomass W=663.283to76.085+3.724D²（R²=0.574）;The total tree biomass W=2117.683+0.001+27.821（D²H） all （D²H）²（R²=0.984）.The optimal model for birch:Dry trunk biomass W=183506.941（D²H）1.162（0.978） or W=6.676D^3.19,（0.978）;Branch branch biomass W=64892.932（D²H）^1.014,（0.973）;The root biomass W=6.35D².894,（0.964）;Leaves biomass W=12589.131（D²H）^0.786，（0.898）；the total tree biomass W=329157.964（D²H）^1.071，（0.979）.The optimal model for aspen:Dry trunk biomass W=111.985D⁽1.702(,（0.983）;Branch biomass W=119.21（D²H）^0.578,（0.907）;Root biomass W=1/（1.205e-5+0.00191x0.77^D）,（0.973）;Leaves biomass W=1/（3.33+0.00369x0.815^D）,（0.922）;The total tree biomass W=1/（2.5e-6+0.000372x0.771^D）,（0.982）.（3） By means of the biomass of Larix principis-rupprechtii、birch and aspen inneedle in mixed needle established the optimal model of various organ biomass, D²H asindependent variables, and then total biomass can be obtained. Total biomass of larch was33490.58kg/ha, birch was41981.41kg/ha, aspen was33632.98kg/ha.