Biomass and Nutrient Accumulation Characteristics of Young Stands of Alnus cremastogyne

摘要

To investigate plant biomass and nutrient distribution and accumulation in organs of Alnus cremastogyne at different ages from 1 to 4 years,the biomass,N,P,K,Ca,Mg,Fe and Zn were tested. The results showed that the average biomass of the whole tree and the biomass of leaf,branch,stem,and root were in positive correlation with tree age,but the growth rate of biomass had a decreasing trend with the tree age increasing,and only the biomass proportion of the trunk in the whole individual plant showed an increasing trend with age. The contents of nutrient elements in organs showed an order of N > Ca > K > Mg > P > Fe > Zn;and the contents of N,P and K were higher in the leaf than in other organs,and the contents of Ca,Mg and Fe in the root were higher than in other organs. The accumulations of N,P,K,Ca,Mg and Zn were the highest in the trunk,and that of Fe was the highest in the root. The annual net accumulations of N,P,K,Ca and Mg in the average trees from 1 to 4 years old were 17. 07,40. 79,95. 82 and 106. 71 g,respectively,and the annual net accumulations of microelements( Fe and Zn) were 335. 04,577. 26,1267 and 1525. 27 mg,respectively.