摘要
广西龙胜县里骆林区25-28年生杉木林乔木层平均每年吸收10种营养元素的总量为139.278kg/ha,其中19.5%存留在立木上,48.1%通过凋落物、32.4%通过降水淋溶归还土壤。N、Mg、S、Mn、Zn、B的归还比都超过0.8;P、K、Ca的归还比加0.72-0.74;Cu的则低于0.7。影响杉木林乔木层营养元素循环的主要因素是土层厚度、土壤养分的浓度和林分测树因子。
The total uptake of the ten nutrient elements of 25-28 years old Cu-nninghamia lanceolata in Guangxi Longsheng county Lilao forest region we-re 139.278 kg/ha·a, 19.5% of which was retained by the tree layer, and48.1% and 32.4% of which were returned to the soil through-litter andrain leaching respectively. The ratio of annual return to annual (?)uptakeof N, Mg, S, Mn, Zn, B was more than 0.8 for N, Mg, S, Mn, Zn andB, was 0.72-0.74 for P, K, Ca, and was under 0.7 for Cu. The main factors which affect the biocycling of nutrient elements onthe tree layer of Cunninghamia lanceolata plantations were the soil depthand the nutrient concentration in soil, and the diameter and height of thetree, etc.
关键词
杉木成熟林
乔木层
生物循环
Cunninghamia lanceolata mature plantation
Tree layer
Biocycling
Ratio of annual return to annual uptake
