林业科学2016，Vol.52Issue(5)：45-54,10.DOI:10.11707/j.1001-7488.20160506
杨树人工林连作与轮作对土壤氮素细菌类群和氮素代谢的影响
Effects of Different Continuous Cropping and Rotation of Poplar Plantation on Soil Nitrogen Bacteria Community and Nitrogen Metabolism
摘要
Abstract
[Objective]Nitrogen is the most important element for poplar plantation productivity. Studies on the dynamic changes of nitrogen cycle bacteria community in continuous cropping and rotation of poplar plantation and the structure features of nitrogen metabolism will help to reveal the obstacle mechanism of continuous cropping to nitrification bacteria in poplar plantation in terms of nutrient cycling.[Method]In this study,the Metagenome sequencing technology was used to study the soil nitrogen cycling bacteria community and the evolvement pattern of nitrogen metabolism along with the continuous cropping generation and different rotation patterns in generation Ⅰ of poplar plantation,continuous cropping generation Ⅱ of poplar plantation,rotated peanut field and the abandoned land after poplar clear cutting.[Result]There were 11 bacteria from 4 genera related to nitrogen cycle,among which Azotobacter had genera of Beijerinckia,Bradyrhizobium,Rhizobium,and Frankia; Nitrobacteria had Nitrobacter,and Nitrosospira; Denitrifying bacteria had Pseudomonas,Ralstonia,Burkholderia,Bacillus,and Streptomyces; Ammonifying bacteria had Bacillus,and Pseudomonas. After the first continuous cropping of poplar plantation,the total number of nitrogen cycling bacteria in the soil increased by 4. 73%,and the type of nitrogen cycle bacteria in the soil remained unchanged. The relative abundance of nitrogen fixing bacteria increased by 53. 44%,nitrification bacteria was no change,denitrification bacteria increased by 0. 14%,and ammonifying bacteria increased by 1. 33%. Compared with generation Ⅱ of poplars,there was no increase or decrease in the type of nitrogen cycle bacteria in the rotated peanut soil. The relative abundance of nitrogen fixing bacteria reduced by 71. 14%,nitrifying bacteria,denitrifying bacteria and ammonifying bacteria increased by 120%, 15. 63% and 20. 76%,respectively. Compared with generation Ⅱ of poplars,species of nitrogen cycle bacteria in the abandoned land soil reduced and the abandoned land was lack of nitrification bacteria. The relative abundance of nitrogen fixing bacteria reduced by 79 . 10%, while denitrifying bacteria and ammonifying bacteria increased by 17 . 39%, 24. 56%,respectively. After the first continuous cropping of poplar plantation,the metabolic activity of soil azotobacteria enhanced,Nitrobacter weakened,Nitrosospira enhanced,and ammonifying bacteria weakened. Compared with generationⅡ of poplars,only the metabolic activity of nitrification bacteria increased,while the other three kinds of nitrogen metabolism function bacteria decreased in rotated peanut field. The metabolic activities of all nitrogen cycling bacteria in the abandoned land were lower than that in generation Ⅱ of poplar plantation. [Conclusion]After the first continuous cropping of poplar plantation,the total number of nitrogen cycle bacteria increased in the soil,but the metabolic activity decreased. After the rotation of peanuts,the most of nitrogen cycle bacteria increased significantly,but only the metabolic activity of the nitrification bacteria increased significantly. Thus,rotation could improve the adverse effects of continuous cropping of poplar plantation on the growth and metabolic activity of nitrification bacteria.关键词
杨树人工林/连作障碍/宏基因组测序技术/细菌类群/氮素代谢Key words
poplar plantation/continuous cropping obstacle/metagenome sequencing technology/bacteria community/nitrogen metabolic分类
农业科技引用本文复制引用
王文波,王延平,王华田,马雪松,伊文慧..杨树人工林连作与轮作对土壤氮素细菌类群和氮素代谢的影响[J].林业科学,2016,52(5):45-54,10.基金项目
国家自然科学基金项目(31270670，31070550) （31270670，31070550）
教育部高等学校博士学科点专项科研基金(20133702110009)。 （20133702110009）
