Research On The Forest Carbon Storage In The Kanas National Nature Reserve

Kanas National Nature Reserve located in the arid area, Xinjiang province, Northwest of China. The taiga forest in southern mountain area was important vegetation in the Kanas Reserve. The main forest type was Larix sibirica Ledeb., their main associated tree species were Picea obovata Ledeb., Abies sibirica Ledeb., Pinus sibirica (Loud.) Mayr., Betula pendula Roth., Populus tremula Linn., and so on. These forest vegetation had high scientific research value on the terrestrial ecosystem. If biomass and carbon storage of the forest vegetation could be assessed properly, it would be provide basic data for forest resource management, global carbon cycle research, and carbon sink evaluation. In this paper, the biomass and its distribution of different forest type were evaluated based on the measured data using the method of relative growth and full harvest combined with the stands investigation data. Carbon storage and carbon density were calculated by biomass and their carbon content of different tree species. The characteristics of spatial distribution of carbon storage were explained based on the topographical map of forest management in the Kanas National Nature Reserve. The results show that:(1) The biomass distribution changed within different organ of P. obovata, L. sibirica, P. sibirica, and B. pendula. But the biomass of trunk was higher than the other organs. The rank of biomass of different organ of P. obovata is trunk> roots> branches> bark> leaf, L. sibirica is trunk> roots> bark> branches> leaf, P. sibirica is trunk> branches> roots> bark> leaf, and B. pendula is trunk> roots> bark> branches> leaf. There were no significant difference between the biomass of branch and root of P. obovata, and P. sibirica (p>0.05), and significant difference among the biomass of all organ of L. sibirica, and B. pendulai(p<.05).(2) There were correlationship between DBH or D2 and biomass of individual tree, and their relationship showed by power function model. The functions of 4 main forest type were as follows:W p. obovata =0.041(D2)0.99、W L.sibirica =0.151(D2)1.164、W P. sibirica =0.146(D2)1.189, and W B. pendula =0.227(D2H)1.224.(3) The rank of total biomass of six different forest types was mixed coniferous forest(221.1917 t/hm2)>L. sibirica pure forest(193.7735 t/hm2)>coniferous and broad-leaved mixed forest(172.0845 t/hm2)> B. pendula pure forest(135.4408 t/hm2)> P. obovata pure forest(128.0474 t/hm2)> P. sibirica pure forest(114.58047 t/hm2)。The vertical distribution of biomass of the six different forest types was tree layer>litter layer>herb layer>moss layer>shrub layer. The aboveground biomass of tree layer and shrub layer of 6 kinds of forest type were all higher than their underground.(4) Biomass of the mixed coniferous forest was the largest in tree layer, and the smallest was P. sibirica pure forest, with a significant difference (p<0.05) between them. Biomass of the mixed coniferous forest is the largest in the shrub layer, the smallest was L. sibirica pure forest, with a significant difference (p<0.05). Biomass of the mixed coniferous forest was the largest in its herb layer, the smallest was B. pendula pure forest, with a significant difference (p< 0.05).(5) Mean carbon content of dominant tree species in the 6 kind of forest type was 45.86%～47.26%. The average carbon content of conifer forest type was 46.24%. The average carbon content of conifer shrub was 36.08%, herb was 31.32%, and litter was 38.04%. According to the biomass weighted calculation, the carbon content of 6 kinds of forest types as follows:L. sibirica pure forest was 46.02%, P. obovata pure forest was 44.51%, P. sibirica pure forest was 44.05%, B. pendula pure forest was 45.37%, coniferous and broad-leaved mixed forest was 46.39%, and the mixed coniferous forest was 46.44%.(6) The total forest vegetation carbon storage was 291.7781 × 104 t, and mean carbon density was 72.90 t/hm2. The sequence of carbon storage and the carbon density of different forest type all were tree layer>litter layer>herb layer >shrub layer. Carbon storage of the tree layer was 288.8062 ×104 t, accounting for 97.83% of the total forest carbon storage in this area. According to weighted calculation, the total carbon storage of forest vegetation about six kinds of forest type was as follow insequence:L. sibirica pure forest> P. sibirica pure forest> P. obovata pure fores> coniferous forest> coniferous and broad-leaved mixed forest> B. pendula pure forest. The average carbon density followed the sequence of coniferous forest> L. sibirica pure forest> coniferous and broad-leaved mixed forest> B. pendula pure forest> P. obovata pure fores> P. sibirica pure forest in the Kanas National Nature Reserve.(7) From the view of regional distribution, the forest carbon storage and carbon density presented a trend of increased from northwest to southeast. Different forest vegetation carbon storage and carbon density had significant difference (p<0.05)。 The highest carbon storage located in the Lake Management Station. The highest carbon density located in Qielegente Station.