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了解土壤氮蓄积率对于计算森林生态系统中氮的临界负荷至关重要。平均蓄积率的计算是基于假定的稳定氮蓄积率,但这种假设可能不正确。本研究调查了森林土壤氮蓄积量的影响因子,即林分年龄和氮沉降;发现腐殖质层中氮的总量随着林分年龄的增加而增加,在这一层中稳定的氮蓄积率约为0.16g/m~2·a。数据还显示,在约70cm以内的土壤层中,氮的蓄积总量会随森林的演替而变化。增加氮沉降对于氮的总量影响不明显。大部分额外施用的氮可能被植物所吸收。
Understanding soil N accumulation is crucial for calculating the critical load of nitrogen in forest ecosystems. The calculation of the average accumulation rate is based on the assumption of a stable accumulation of nitrogen, but this assumption may not be correct. In this study, we investigated the influencing factors of nitrogen accumulation in forest soils, that is, stand age and nitrogen deposition. The total amount of nitrogen in humus layer increased with the increase of stand age, and the stable nitrogen accumulation in this layer was about 0.16 g / m 2 · a. The data also shows that in the soil layer within about 70 cm, the total amount of nitrogen accumulated varies with the forest succession. Increasing the nitrogen deposition has no obvious effect on the total amount of nitrogen. Most of the additional nitrogen applied may be absorbed by the plants.