A Study of the Distribution and Accumulation of Major Nutrient Elements in Different Densities of Eucalyptus grandis

In this paper,studies were made of the distribution and accumulation of major elements of 5-year old Eucalyptus grandis forest with the densities of 556 trees per hectar and 1667 trees per hectar.The results showed that:①The distribution of major nutrient element content in different organs of 2 kinds of densities was nearly the same.And the ranked order was leaf > tree trunk > big branch or branchlet > fruit > bark; ②From the distribution of nutrient elements and organic matter in the trunk,P,K,Mg and Ca content presented basically increasing along with the trunk height.And the organic matter content increased with the trunk height in low density stand,while the result was opposite in high density stand.At the same time,N content increased witn the trunk height in low density stand,but the content in high density increased after the decrease and increased at the last.③From the ditribution of biomass,the ranked ordered was tree trunk > bark or big branch > branchlet > leaf > fruit.④The accumulation of major nutrient element content in different organs of 2 kinds of densities was nearly same.Ca content was the highest in two kinds of piantations,followed by N,K,Mg and P content.Ca content was 601.78 kg per hectare in low density stand and 1 204.43 kg per hectare in high density stand.