四川盆地亚热带常绿阔叶林表层土壤氮截留与淋溶流失特征  

The Characteristics of Nitrogen Retention and Leaching of Surface Soil in the Subtropical Evergreen Broad-Leaved Forest in Sichuan Basin

作　　者：王滨[1] 吴福忠[1] 杨万勤[1] 李俊[1] 彭艳[1] 曹瑞[1] 

机构地区：[1]四川农业大学生态林业研究所,林业生态工程四川省重点实验室,高山森林生态系统定位研究站,成都611130

出　　处：《水土保持学报》2015年第6期45-52,共8页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(31270498,31200474);国家“十二五”科技支撑计划项目(2011BAC09B05);四川杰出青年学术与技术带头人培育项目(2012JQ0008,2012JQ0059)

摘　　要：以四川盆地典型桢楠（Phoebe zhennan）和马尾松（Pinus massoniana）人工林为研究对象,于2013年12月至2014年12月,采用原位培养法监测了雨季（3个时期）和旱季（2个时期）5个关键时期土壤N截留和淋溶输出特征。结果表明：马尾松人工林土壤的N截留和淋溶输出总量分别为17.82,26.95kg/（hm2·a）,桢楠人工林土壤的N截留和淋溶输出总量分别为8.90,17.98kg/（hm2·a）,2种人工林土壤均表现出明显的N截留作用,且硝态氮和水溶性有机氮的输入与输出量显著高于铵态氮和亚硝态氮（P〈0.01）。此外,2种人工林土壤N输入和输出均表现出显著的季节性差异,59.64%～77.14%的N输入过程都发生于旱季末期和雨季早期,且这2个时期的土壤N淋溶输出量分别占全年的44.86%～52.70%。2种人工林土壤在旱季主要表现为N截留效应,而雨季主要表现为N流失。相关性分析结果表明,除桢楠人工林的铵态氮和马尾松人工林的硝态氮外,2种人工林土壤N库的其余N组分淋溶输出量与降水量呈极显著正相关（P〈0.01）,土壤对可溶性无机氮的截留量则与降水量呈负相关。总体而言,桢楠和马尾松人工林土壤N输入、输出和截留作用主要发生于旱季末期,且以硝态氮和水溶性有机氮为主。In order to investigate the characteristics of soil nitrogen retention and leaching in the dry and rainy seasons in Sichuan Basin,an in situ incubation of soil cores were conducted in the Phoebe zhennan and Pinus massonianaplantations for one year（December,2013 to December,2014）,and the year can be divided into early dry season,late dry season,early rainy season,middle of the rainy season and late rainy season.The results showed that in P.massonianaplantation,the retention and leaching amount of nitrogen in soil were17.82kg/（hm2·a）and 26.95kg/（hm2·a）,respectively,and in P.zhennan plantation,they were 8.90kg/（hm2·a）and 17.98kg/（hm2·a）,respectively.Soil nitrogen retention was observed inboth plantations,and the input and output of soil nitrate nitrogen and dissolved organic nitrogen were higher than those of ammonium nitrogen and nitrite nitrogen（P〈0.001）.The input and output of nitrogen showed significant differences in5 periods in both plantations,with 59.64%—77.14% of nitrogen input and 44.86%—52.70% of nitrogen output in late dry season and early rainy season.In addition,soil nitrogen retention effect was more obvious in dry season,while soil nitrogen leaching was more significant in rainy season.The correlation analysis showed that the leaching outputs of soil nitrogen components in 2plantations,except ammonium nitrogen in P.zhennan plantation and nitrate nitrogen in P.massoniana plantation,had strong positive correlations with precipitation amount（P〈0.01）,while the retention amount of soil inorganic nitrogen was negatively correlated with precipitation.In conclusion,the input,output and retention of soil nitrogen mainly occurred in late rainy season in P.zhennan and P.massoniana plantations,and the nitrate and dissolved organic nitrogen were the main forms of soil nitrogen.

关 键 词：土壤氮截留 土壤氮输入 土壤氮淋溶 桢楠人工林 马尾松人工林 常绿阔叶林 

分 类 号：S714.8[农业科学—林学] S158.5