Abstract: Soil microbial community plays a crucial role in ecological sustainability in response to different land use patterns. In this paper, soil samples were collected from the cropland, naturally restored forestland, and tea garden on the red soil sloping land at the Taoyuan Agro-ecosystem Research Station (110°
72″E, 28°52″N) under Chinese Academy of Sciences to study the effects of different land use patterns on the soil microbial diversity and nitrification potent
ial. T-RFLP technique was adopted to study the diversity of bacteria, ammonia-oxidizing bacteria (AOB), and ammonia-oxidizing archaea (AOA), and aerobic culture method was used to study the nitrification potential. Under the three land use patterns, the diversity index of soil bacteria, AOB, and AOA showed the same variation trend, i.e., cropland = tea garden > naturally restored forest land (P<0.05). RDA analysis showed that the variations of soil physical and chemical properties under different land use patterns determined the community structure of soil AOB and AOA. Cropland soil had the highest nitrification potential, followed by tea garden soil, and naturally restored forestland soil. There was a significant positive correlation between the diversity index of soil bacteria, AOB, and AOA and the soil potential nitrification rate, especially for AOA, suggesting that AOA might play an important role in red soil nitrification.

Key words: Mikania micrantha, Volatile oil, Insects, Biological activity