生态学杂志2012，Vol.31Issue(8)：1893-1902,10.
模拟氮沉降对温带阔叶红松林地土壤氮素净矿化的影响
Effects of simulated nitrogen deposition on soil nitrogen mineralization in a temperate broadleaf-Korean pine (Pinus koraiensis) forest
摘要
Abstract
Taking a broadleaf-Korean pine ( Pinus koraiensis) forest in Changbai Mountains of Northeast China as the object, an in situ experiment was conducted in 2006-2008 to study the effects of simulated nitrogen deposition on the seasonal and annual dynamics of soil net nitrogen mineralization, including net ammonification and net nitrification, in humus layer (0-7 cm) and uppermost mineral layer (0-15 cm) in the forest. The applied nitrogen forms were (NH4)2SO4, NH4C1, and KNO3, and their application rates were 0, 22. 5 , and 45 kg N · hm-2 · a-1. During the study period, the annual soil nitrogen mineralization flux in the forest was 1. 2-19. 8 kg N · hm-2 · a-1 . In the two soil layers, the net nitrogen mineralization flux was significantly higher in 2008 than in 2006 and 2007 (P < 0. 05 ). The soil net N mineralization rate was increased with nitrogen input, especially the input of (NH4)2SO4 or NH4C1 (P<0.05) , but this promotion effect decreased with the extension of years. Nitrogen deposition, especially NH4C1, had more obvious promotion effect on the net ammonification and net mineralization rates in humus layer than in the uppermost mineral layer. The previous researches on the annual fluxes of net nitrogen mineralization in forest soils in global scale also showed that the soil net nitrogen mineralization rate was increased significantly with increasing atmospheric nitrogen deposition, and the variation of atmospheric nitrogen deposition accounted for 52% of the variation of soil net nitrogen mineralization rates across the forests. In this study, nitrogen deposition (x1 ) and soil pH (x2) could explain 70% of the variation of soil net nitrogen mineralization rate (y) ( y= 0. 54x1-18. 38x2-109. 55, R2=0. 70, P<0. 0001). The previous researches only provided the annual temperature in research areas, not considered the influence of the accumulative temperature, which could be the causes of non-relationship between soil nitrogen mineralization and temperature. The future research should pay more attention to the observation of soil accumulative temperature in different regional forests.关键词
氮沉降/森林土壤/氮素转化/通量Key words
nitrogen deposition/ forest soil/ nitrogen transformation/ flux.分类
生物科学引用本文复制引用
韩琳,王鸽..模拟氮沉降对温带阔叶红松林地土壤氮素净矿化的影响[J].生态学杂志,2012,31(8):1893-1902,10.基金项目
国家青年自然科学基金项目(41105101)、中国气象局成都高原气象研究所开放实验室课题基金项目(LPM2009018和BROP201001)和成都信息工程学院校引进人才启动基金项目(KYTZ201011)资助. （41105101）
