5 Year Old Tectona Grandis Plantation In Southern Sutropical Region

Teak (Tectona grandis Linn F.), belonging to the family of Verbenaceae, positive, and pioneer species, naturally distributes in tropical India, Burma, Thailand and Laos and other countries or regions. Teak is recognized as one of the precious timber species. In this paper, the growth, biomass and productivity of the 5 year old teak plantation were researched, the storage and distribution of carbon and nutrient elements content was also discussed, in order to reveal the growth, carbon storage and nutrient cycling characteristics of teak plantation, providing theoretical basis and technical support. The results showed that:(1) Growth:Tree height, DBH and Volume of 5 year old teak plantation increased with stand age; the continual annual increment of tree height and DBH in fourth years was the fastest, and the growth of teak plantation in the southern subtropical region was good.(2) Stand biomass and productivity:The biomass of 5 year old teak plantation tree layer was 21.05 t/hm2, accounting for 91.68%, the understory vegetation was 0.44 t/hm2, accounting for 1.92%, the litter layer was 1.47 t/hm2, accounting for 6.41%. The order of organs was: Stem> Branch>Root pocket> Bark> Leaf> Coarse root> Middle root> Fine root. The productivity of tree layer was 4.21 t/hm2.a, the net primary productivity in various organs as orders:Stem> Branch>Root pocket> Bark> Leaf> Coarse root> Middle root> Fine root(3)Carbon storage:In 5 year old teak plantation, the average carbon contents of various organs in tree layer were between 426.1-504.8 g/kg, the tree layer carbon content in different organs was the highest in the trunk. The carbon content of the soil decreased with soil depth. The ecosystem carbon storage of 5 year old teak plantation was 46.40 t/hm2, as the Soil layer> Tree layer> Litter layer> Shrub and grass layer.(4)Nutrient accumulation:In 5 years old teak plantation, the major nutritional contents were as orders:Ca (9.49 g/kg)> K(6.23 g/kg)> N (6.13 g/kg)> Mg (1.68 g/kg)> P (1.39 g/kg), showing that the growth of teak plantation mostly needed calcium, potassium, nitrogen. Various nutrients storages were as orders:Ca>K>N>P> Mg, as 104.45 kg/hm2,111.58 kg/hm2,28.77 kg/hm2,200.40kg/hm2,24.89 kg/hm2, respectively. The total nutrition reserves of various organs were as the orders:Bark> Stem> Branch> leaf> Root pocket> Coarse root> fine root> middle root. In the fast-growing stage, per It dry matter production of teak plantation required 5 kinds of nutrient elements as a total of 22.33 Kg. comparing to other species, the nutrient use efficiency of teak plantation is low.