Nutrient Accumulation and Distribution of Mature Pinus massoniana Plantation in Northwestern Guangxi

摘要

cqvip:[Objectives]This study was conducted to reveal the characteristics of nutrient absorption and accumulation in Pinus massoniana plantations in Northwestern Guangxi.[Methods]Based on field investigation and indoor analysis,the contents,accumulation and annual net accumulation of five nutrient elements(N,P,K,Ca and Mg)in a mature P.massoniana plantation(26-year-old)in Nandan County,Guangxi Province were studied.[Results]The contents of nutrient elements in different organs of the mature P.massoniana plantation were the highest in the leaves,followed by the bark,branch and root,and the lowest in the stem.In general,among the contents of the five elements in different organs,N content was the highest,followed by K or Ca,and P and Mg were the lowest.The total accumulation of nutrient elements in the 26-year-old mature P.massoniana plantation in northwestern Guangxi was 1 384.05 kg/hm^2.Among the different structural levels of the stand,the tree layer had the highest accumulation of nutrient elements,which was 1 198.41 kg/hm^2,accounting for 86.59%of the total accumulation of nutrients in the plantation,and the accumulation of nutrients in other layers from the largest to the smallest was the litter layer(91.97 kg/hm^2),herb layer(49.86 kg/hm^2)and shrub layer(43.92 kg/hm^2),accounting for 3.17%,3.60%and 6.64%of the total nutrient accumulation of the plantation,respectively.The annual net accumulation of nutrient elements in the tree layer of the mature P.massoniana plantation was 46.09 kg/(hm^2·a),and the order of the annual net accumulation of different nutrient elements followed N>K>Ca>Mg>P;and the accumulation of 1 t of dry matter needed 6.37 kg of the five nutrients.[Conclusions]This study provides a scientific basis for the rational management of P.massoniana plantations,especially forest soil management.