The Model Of Biomass And Carbon Of Shrub And Herb Under Three Forest Types

In the study, The understory vegetation of Cunninghamia Lanceolata and Pinus massoniana of three forest types in Jiangle country,Fujian Province as the research object, constructed the organs and the whole plant biomass models, with plant height(H), base diameter (D), crown(C) of shrub and herb as the independent variable to estimate the biomass and carbon storage by containing carbon rate. In the final,we analysis the distribution of biomass and carbon storage of understory vegetation in different forest types and different ages for providing a reasonable and scientific basis of forest ecosystem productivity and carbon storage in future system, a comprehensive study. The main results are as follows:(1) Eight kinds of shrubs and four kinds of herbal components and whole plant optimal biomass model to base diameter (D) for the variable power function, followed by base diameter(D), plant height(H) or crown(C), plant height(H) as two independent variables power function and a minimum of height(H) to the variable power function. As the R2 (judging coefficient) and P%(prediction accuracy) of the model are relatively high, the results are better than others. Through the optimal biomass model to calculate the biomass of the understory vegetation in different forest types,the understory vegetation, shrub layer, the shrub layer is 2.130t-hm"2,0.890 t·hm-2,1.240t·hm-2 under Chinese fir pure forest; the understory vegetation, shrub layer, the shrub layer is 3.270t·hm-2,1.210 t·hm-2,2.060t·hm-2 under Pinus massoniana pure forest; the understory vegetation, shrub layer, the shrub layer is 6.060t·hm-2,2.110 t·hm-2,3.950t·hm-2 under the mixed forest of Chinese fir and Pinus massoniana.(2) Carbon density of forest vegetation layer:According to biomass model for estimating components and total biomass and carbon density of the understory vegetation, by multipling the corresponding containing carbon rate (shrub leaves, stems, roots containing carbon rate were 48.93%,47.32%,44.75%, herb layer (stem and leaf) and root containing carbon rates were 42.12%,40.20%). The carbon density of understory vegetation in different forest types is 1.010tC·hm-2 under Chinese fir forest,1.386tC·hm-2 under Pinus massoniana pure forest,2.637tC·hm-2 under the mixed forest of Chinese fir and Pinus massoniana. And the annual storage carbon is 0.0605 tC·hm-2·yr-1 under Chinese fir forest,0.0807 tC9hm-29yr-1 under Pinus massoniana pure forest,0.1392 tC9hm-29yr-1 under the mixed forest of Chinese fir and Pinus massoniana.(3) To simplify the workload of carbon reserves of estimating understory vegetation biomass through shrub and herb biomass model, established the regression equation of the forest age factor and the understory vegetation carbon. Except the optimal model is power function (Y=aAb) for the carbon model of shrub layer under masson pine and the mixed forest of Chinese fir and Pinus massoniana,the remaining carbon storage model of he understory vegetation are cubic curve model (Y=a+bA+cA2+dA3) in different forest type,and the results of model showed that R2 (coefficient of judgment)=1, P (estimation accuracy)= 1, see (residual standard deviation)< 0.151, average relative error (E)= 0, average absolute value of relative error (E) is less than or equal to 0.187, so the model fitting effect is excellent (Note:when R2, P is close to 1, and SEE, E, e closer to 0,the model is well).