【摘要】 球囊霉素相关土壤蛋白（Glomalin-related soil protein,GRSP）的变化情况是评价和指示土壤碳（C）库动态变化的重要指标。了解大气氮（N）沉降增加背景下GRSP的变化机制对于阐明土壤C循环的驱动因素具有重要意义。于2011年5月开始,在大兴安岭进行野外N沉降试验,共设置4个水平N添加处理,分别为对照(Control,0 g·m^-2·a^-1)、低N(LN,2.5 g·m^-2·a^-1)、中N(MN,5 g·m^-2·a^-1)和高N(HN,7.5 g·m^-2·a^-1)处理,探索GRSP对N沉降的影响机制。结果表明,（1）对于易提取球囊霉素（EE-GRSP）,所有施N水平都增加了其在土壤中的含量;对于总球囊霉素（T-GRSP）,LN和MN表现为显著促进作用（P<0.05）,HN表现为抑制作用。（2）T-GRSP与EE-GRSP含量与SOM均表现出显著正相关关系（P<0.05）。施N使GRSO对土壤有机质（SOM）的贡献率增加了0.59%-1.07%。低中水平N沉降（LN和MN）显著促进了土壤有机质（SOM）的积累（P<0.05）,高水平N沉降（HN）处理则表现为抑制。此外,大兴安岭兴安落叶松林GRSP对SOM的贡献率相对较低。（3）在气候变化背景下,低中水平N沉降能通过提高GRSP的量促进SOM的累积,而高水平N沉降则通过减少GRSP的量从而降低土壤总SOM。低中水平N沉降可以增加GRSP和SOM含量,进而提高生态系统固C潜力,减缓大气CO₂浓度升高带来的压力。更多还原

【Abstract】 The changes of glomalin-related soil protein（GRSP） are important indicators for evaluating and indicating the dynamic changes of soil carbon（C） pool. Understanding the GRSP change mechanism under the background of increasing atmospheric nitrogen（N） deposition is of great significance to elucidate the driving factors of soil C cycle. Therefore, this study conducted field control experiments on the experimental sample site located in Greater Khingan Mountains to explore the influence mechanism of GRSP on N deposition. In the test sample, the N addition treatment was started in May 2011, and a total of four levels of N addition treatment were set, which were control(Control, 0 g·am^-2·a^-1), low N(LN, 2.5 g·m^-2·a^-1), medium N(MN, 5 g·m^-2·a^-1) and high N(HN, 7.5 g·m^-2·a^-1) treatment. The results showed that,（1） Easy extract glomalin（EE-GRSP） increased in soil of all N levels, and total glomalin（T-GRSP） in LN and MN treatment was significantly promoted（P<0.05）, but it showed inhibition in HN treatment.（2）There was a significant positive correlation between the contents of T-GRSP and EE-GRSP and soil organic matter（SOM）（P<0.05）.The contribution rate of GRSO to SOM increased by 0.59%-1.07% with N application. Low and medium level N deposition（LN and MN） significantly promoted the accumulation of SOM（P<0.05）, while high level N deposition（HN） was inhibited. In addition, the contribution rate of GRSP to SOM of deciduous pine forest in Greater Khingan Mountains was relatively low. And（3） in the context of climate change, low and medium level N deposition could increase the accumulation of SOM by increasing the amount of GRSP,while high level N deposition could reduce the total SOM of soil by reducing the amount of GRSP. This indicates that the low and medium level N deposition can increase GRSP and SOM content, thereby improving the potential of solid C in the ecosystem and alleviating the pressure caused by the increase of atmospheric CO₂ concentration.更多还原