Study On Biomass And Carbon Absorption Of Apple Economic Forest In The Residual Gully Area Of Shaanxi Province

This paper takes the apple economic forest in the juvenile,early fruit,fruity and senescent stages of the stagnation and gully region of Shaanxi Province as the research object.The biomass and distribution characteristics of apple economic forest in different growth periods were analyzed by constructing the equation of apple tree organs biomass and total biomass in the residual tableland and gully region of Shaanxi province.By calculating the annual net increase of apple tree biomass,the annual biomass,annual litter amount and fruit yield of the same year were investigated,and the annual carbon sequestration of apple orchard ecosystem in different growth periods was obtained,and the carbon density of apple economic forest is obtained by the economic biomass,carbon content and soil carbon density of apple economic forest.The main research results are as follows:(1)The equation of apple tree biomass suitable for the gully region of the loess plateau in Shaanxi province was fitted,in which:WTrunk=0.019(D0.22H)0 962?WBranch=0.009(D0.22H)1.086?WLeavws=0.005(D0.22H)0.865?WRoot=0.015(D0.22H)0.976?WTotal=0.044(D0.22H)1009,The R2of the equation is between 0.971 and 0.991,and the prediction accuracy is between 80.03%and 88.07%.(2)The total biomass of apple economic forest in juvenile,early fruit,fruit and senescence stages were 10.92 t·hm-2,8.96 t·hm-2,17.43 t·hrm-2 and 37.16 t·hm-2,respectively.As the age of apple trees continues to increase,the forest biomass allocation characteristics of apple economic forests are:The biomass of the arbor layer of the apple economy forest is constantly growing,accounting for between 3.75%and 96.53%.With the stop of intercropping and the change of intercropping type and area,the biomass of the lower layer of apple economic forest is continuously decreasing,accounting for 96.25%?3.47%.(3)The net primary productivity of the apple orchard ecosystem in infancy,early fruiting,full fruit period,and senescence period are respectively 5.167 t·hm-2·a-1,2.508 t·hm-2·a-1,4.632 t·hm=2·a-1,3.991 t·hm-2·a-1,the absorption amount converted into CO2 is respectively 18.948 t·hm-2·a-1,9.197 t·hm-2·a-1,16.984 t·hm-2·a-1,1.637 t·hm-2·a-1.The magnitude of net primary productivity in different periods is:infancy>full fruit period>senescence period>early fruiting.The carbon density of apple economic forest in the early,early fruit,fruit and senescence periods was 103.36 t·hm-2,89.8 t·him-2,95.36 t·hm-2,and 67.81 t·hm-2.