森林土壤吸收人为氮源的能力  

The Capacity of Forest Soil to Absorb Anthropogenic N

作　　者：Trine A. Sogn Arne O. Stuanes Gunnar Abrahamsen 何萍 

机构地区：[1]挪威农业大学土壤与水科学系 [2]中国环境科学院环境生态研究所

出　　处：《AMBIO－人类环境杂志》1999年第4期346-349,共4页

摘　　要：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。Knowledge of the N accumulation rate in soil is crucial for the calculation of 'critical loads' of N in forest ecosystems. Calculations of an average rate is based on an assumed constant rate of N accumulation, which may not be correct. In the present study, variations in N accumulation in forest soil due to i) stand age; and ii) N deposition have been investigated. An increase in total amount of N in the mor layer with increasing forest stand age was observed, indicating a constant N accumulation rate of approximately 0.16 g N m-2y r-1 in this layer. However, the data showed that the total accumulation of N in the soil down to about 70 cm may vary during the forest succession. No significant effect of increased N deposition on the total amount of N was observed. Most of the extra N applied seemed to be taken up by the plants.

关 键 词：森林土壤 氮蓄积量 氮沉降 土壤肥力 

分 类 号：S714.8[农业科学—林学]