title: Nitrogen mass balance in a constructed wetland treating piggery wastewater effluent.
abstract: The nitrogen changes and the nitrogen mass balance in a free water surface flow constructed wetland (CW) using the four-year monitoring data from 2008 to 2012 were estimated. The CW was composed of six cells in series that include the first settling basin (Cell 1), aeration pond (Cell 2), deep marsh (Cell 3), shallow marsh (Cell 4), deep marsh (Cell 5) and final settling basin (Cell 6). Analysis revealed that the NH(+)4-N concentration decreased because of ammonification which was then followed by nitrification. The NO(-)2-N and NO(-)2-N were also further reduced by means of microbial activities and plant uptake during photosynthesis. The average nitrogen concentration at the influent was 37,819 kg/year and approximately 45% of that amount exited the CW in the effluent. The denitrification amounted to 34% of the net nitrogen input, whereas the accretion of sediment was only 7%. The biomass uptake of plants was able to retain only 1% of total nitrogen load. In order to improve the nutrient removal by plant uptake, plant coverage in four cells (i.e., Cells 1, 3, 4 and 5) could be increased.
authors: Water Environment Research Dept., National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, 404-708, Korea. Electronic address: leeso1018@korea.kr.
authors: Soyoung
authors: S
authors: Lee
authors: Department of Civil and Environmental Engineering, Kongju National University, 275 Budaedong, Seobukgu, Cheonan, Chungnamdo, 331-717, Korea.
authors: Marla C
authors: MC
authors: Maniquiz-Redillas
authors: Department of Civil and Environmental Engineering, Kongju National University, 275 Budaedong, Seobukgu, Cheonan, Chungnamdo, 331-717, Korea.
authors: Jiyeon
authors: J
authors: Choi
authors: Department of Civil and Environmental Engineering, Kongju National University, 275 Budaedong, Seobukgu, Cheonan, Chungnamdo, 331-717, Korea. Electronic address: leehyung@kongju.ac.kr.
authors: Lee-Hyung
authors: LH
authors: Kim
mesh_terms: D000818:Animals; D019015:Geologic Sediments / Q000737:chemistry; D009584:Nitrogen / Q000032:analysis*; D010944:Plants / Q000737:chemistry; D013552:Swine; D062065:Wastewater / Q000032:analysis*; D018508:Water Purification; D053833:Wetlands
chemical_list: D009584:Nitrogen; D062065:Wastewater
keywords: constructed wetland; livestock wastewater; nitrogen mass balance; plant uptake; sediment