原始红松林及其次生林土壤游离氨基酸季节动态变化

Seasonal Dynamics of Soil Free Amino Acids in Virgin Forest and Secondary Forest of Korean Pine in Xiaoxing’an Mountains

以凉水国家自然保护区内原始红松林及其次生林土壤为研究对象,测定了土壤游离氨基酸(TFAA)的质量分数,并分析了其与土壤铵态氮NH4+—N、硝态氮NO3-—N、有机质、全氮、水解氮的质量分数及含水率的关系。结果表明:原始红松林及其次生林的游离氨基酸质量分数都在7、8、9月呈现"V"型变化趋势;在同一月份中,TFAA、NH4+—N、NO3-—N之间具有相同的差异性关系,不同月份差异性不同。对土壤A层各形态氮素的质量分数及土壤基本性质指标进行相关分析可知:土壤游离氨基酸的质量分数与铵态氮、硝态氮、有机质、全氮、水解氮质量分数及含水率之间均不相关。对土壤A0及A层各指标进行相关分析可知:土壤游离氨基酸质量分数与铵态氮、硝态氮、全氮、水解氮质量分数以及含水率均相关性极显著(p<0.01),与有机质质量分数不相关。

Content of soil total free amino acids （TFAA） was measured in virgin forest and secondary forest of Korean pine in Liangshui National Nature Reserve.The relationships between TFAA and soil ammonium nitrogen,nitrate nitrogen,moisture content,organic matter,total nitrogen and hydrolysable nitrogen were also analysed.The variation in TFAA content in both the virgin forest and the secondary forest of Korean pine could be described as a V-shaped curve from July to September.TFAA,NH4^＋-N,NO3^--N in the virgin forest showed the same variation with those in the secondary forest in the same month,but various in different months.A correlation analysis was made for content of different forms of nitrogen and the basic characteristics of soil in 0-15 cm（A） layer between the two forests.Results show that there is no correlation between TFAA content and ammonium nitrogen,nitrate nitrogen,water content,organic matter content,total nitrogen content,hydrolysable nitrogen content.A correlation analysis between A layer and A0 layer（litter layer） indicates that TFAA content is significantly correlated with ammonium nitrogen,nitrate nitrogen,water content,total nitrogen content and hydrolysable nitrogen content（p〈0.01）,while it is not related with organic matter content.