title: Impact of plant harvest management on function and community structure of nitrifiers and denitrifiers in a constructed wetland.
abstract: Plant harvest is one of the most important management practices in constructed wetlands. In this study, we evaluated the impact of harvesting Phragmites australis (Cav.) Trin. ex Steudel on the activity and community structure of nitrifiers and denitrifiers in a free-water surface constructed wetland. The nitrifiers were targeted using bacterial and archaeal-amoA that encode ammonia monooxygenase, and the denitrifiers were targeted using nirK and nirS that encode the nitrite reductase. The community structures were evaluated using denaturing gradient gel electrophoresis. The potential nitrification and nitrate reduction rates were shown to be significantly higher in the harvested plant rhizosphere than in a non-harvested control plot. The potential nitrification rate positively correlated with the potential nitrate reduction rate and influenced the community structure of nirK. In addition, plant canopy developed differently after harvest and simultaneously changed the microclimate beneath the plant community. These results suggest that plant harvest management could change subsequent plant development and associated microenvironments, thereby affecting the function and community structure of nitrifiers and denitrifiers. Our study highlights the importance of plant harvest management within constructed wetlands to regulate the functions of nitrification and denitrification.
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 Jingming Road (South), Chenggong New District, Kunming, Yunnan 650500, China Graduate School of Agriculture, Kyoto University, Oiwake Kitashirakawa Sakyo, Kyoto 606-8502, Japan.
authors.forename: Takashi S T
authors.initials: TS
authors.lastname: Tanaka
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 Jingming Road (South), Chenggong New District, Kunming, Yunnan 650500, China irbis.chagan@gmail.com.
authors.forename: Chagan
authors.initials: C
authors.lastname: Irbis
authors.affiliation: Kunming Agrometeorological Station, Kunming, Yunnan 650228, China.
authors.forename: Pengyun
authors.initials: P
authors.lastname: Wang
authors.affiliation: Graduate School of Agriculture, Kyoto University, Oiwake Kitashirakawa Sakyo, Kyoto 606-8502, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Inamura
mesh_terms: D001105:Archaea / Q000201:enzymology / Q000235:genetics; D001419:Bacteria / Q000201:enzymology / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D058440:Denitrification; D009566:Nitrates; D058465:Nitrification; D009572:Nitrite Reductases / Q000235:genetics; D010088:Oxidoreductases / Q000235:genetics; D006109:Poaceae / Q000382:microbiology*; D058441:Rhizosphere; D053833:Wetlands
chemical_list: D009566:Nitrates; D010088:Oxidoreductases; D009572:Nitrite Reductases; C045582:ammonia monooxygenase
keywords: PCR-DGGE; denitrification; harvesting reed; nitrification