摘要
为了解短期（两年）氮添加对土壤物理结构的影响,采用野外调查取样和室内分析结合的方法,对盐城市东台林场中不同龄级杨树人工林进行施氮试验,分析土壤表层（0-10cm）水稳态土壤团聚体直径以及细根生物量的变化。结果表明：1）不同林龄杨树人工林土壤团聚体粒径受细根生物量影响显著增大,对于氮素输入的响应规律各不相同,5年生林土壤对氮添加的响应比9年生和16年生林反应明显;2）轻度氮添加（每年5g/m^2）有利于土壤物理结构改善,而中等浓度氮添加（每年10g/m^2）会造成大直径团聚体质量百分比减少,导致土壤团聚体平均直径下降;3）细根生物量与大直径土壤团聚体的质量百分比呈线性正相关。因此,林龄与氮添加导致的细根生物量的增大有利于大直径土壤团聚体的形成。
The water-stable aggregates＇ diameter and fine roots＇ biomass in different surface soil layers（0-10cm）of poplar plantations with different stand age applied with different nitrogen level were determined by field survey and indoor analysis to study the effect of nitrogen addition（during two years）on soil physical structure.The results showed that：1）The biomass of fine roots has the significant effect on water-stable aggregates＇ diameter of poplar plantations with different stand age,and soil response of Poplar plantations with 5-year age to nitrogen addition is higher than Poplar plantations with 9-year age and 16-year age obviously;2）Mild nitrogen addition（5g/m^2· y）can improve the soil physical structure.but medium nitrogen addition（10g/m^2· y）can reduce mass percentage of water-stable aggregates with larger diameter,which results in decrease of average diameter of soil aggregates;3）There is a positive correlation between fine roots＇ biomass and mass percentage of soil aggregates with larger diameter.Therefore,the increase of fine roots＇ biomass caused by stand age and nitrogen addition is beneficial to formation of soil aggregates with larger diameter
出处
《贵州农业科学》
CAS
北大核心
2014年第12期129-133,共5页
Guizhou Agricultural Sciences
基金
国家重点基础研究发展计划项目"我国主要人工林生态系统的结构
功能与调控研究"(2012CB416904)
江苏省基础研究计划(自然科学基金)青年基金项目"氮沉降对杨树人工林SOC同位素效应的影响"(BK20130973)
江苏高校优势学科建设工程资助项目"南京林业大学生物学优势学科建设工程资助项目"(PAPD)
关键词
氮添加
杨树人工林
水稳态团聚体
细根
nitrogen addition
poplar plantation
water-stable aggregate
fine root
作者简介
邢玮（1981-），女，博士，助理研究员，从事森林生态学研究。E—mail：nerring@163．com
通讯作者：葛之葳（1981-），男，博士，讲师，从事森林生态学、土壤生态学研究。E-mail：nerrynor@163．com
