关键词: 氮磷沉降, 竞争作用, 微生物, 驱动机制

Abstract: Methane (CH₄),as an important greenhouse gas,played an important role in the process of global change,small variations of CH₄ may lead to large changes in climate. There were many studies on the nitrogen (N) impact on CH₄ uptake,but fewer studies on the effects of phosphorus and interaction of nitrogen-phosphorus (N-P) on CH₄ uptake in dryland. In this review,we summarized the current status of the N,P effects and their interaction on CH₄ uptake in dryland,and identified out that the effect of N on CH₄ have already gone through three stages:first,uncertainty about the conclusions about that effect (inhibitory,enhancing,and neutral),followed by some primary mechanisms investigation (e.g.,environmental factors:temperature,moisture,pH,Eh,etc.),then the basic conclusion of the “low-promotion and high-inhibition” for N effect on CH₄ oxidation,and the insights into microbial driving mechanism on this phenomenon. It was also found out that the inhibitory effect of N on CH₄ uptake was mainly due to the competition between NH⁺₄ and CH₄. While P effect on CH₄ had been less studied and that effect remains uncertain. The interaction of N and P on CH₄ uptake was even less studied,especially whether the P would induce the change of N effect on CH₄ has not been studied yet. Based on the review of previous studies,the knowledge gaps about the effects of P and interaction of N and P on CH₄ in arid and semi-arid grassland ecosystem were identified,and the latest research progresses in the recent decades were briefly introduced and summarized up. It has been concluded the phosphorus deposit alleviate the N-suppression on CH₄ uptake in semi-arid grassland ecosystems,and that alleviative effect exists on global scales as well. Finally,the possible research directions and hot issues in this field were put forward for coming days.

Key words: N and P deposition, Competition, Microbes, Driving mechanisms