|Ibekwe, Abasiofiok - Mark|
|Ma, J. - Jilin University|
|Murinda, Shelton - California Polytechnic State University|
|Reddy, G - North Carolina Agricultural And Technical State University|
Submitted to: Hydrology: Current Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2017
Publication Date: 6/10/2017
Citation: Ibekwe, A.M., Ma, J., Murinda, S., Reddy, G.B. 2017. Microbial diversity of bacteria, archaea, and fungi communities in a continuous flow constructed wetland for the treatment of swine waste. Hydrology: Current Research. 8(2):1-8. doi: 10.4172/2157-7587.1000277.
Interpretive Summary: Constructed wetlands can offer significant benefits such as water-quality improvement, water reclamation, habitat for species conservation, flood control, recreational and education activities for human populations in both developed and developing countries. In the swine production system, wastes are traditionally flushed into an anaerobic lagoon and then later sprayed on agricultural fields. The lagoon and spray field system is the most commonly used method to dispose of liquid waste from swine houses. In this study, a continuous marsh constructed wetland was used to remove contaminants from swine waste. We employed pyrosequencing, an advanced DNA sequencing method to assess bacterial, archaeal, and fungal composition within a surface flow constructed wetland to determine their spatial dynamics and contaminant removal within the wetland. We determined that a substantial population of bacteria and archaea in the midsection of the wetland were associated with nitrogen removal. This information will be of interest to swine farmers, water quality agencies, government agencies, and researchers.
Technical Abstract: Contaminant removal in constructed wetlands may largely be a function of many microbial processes. However, information about bacterial, archaea, and fungi communities in constructed wetlands for the removal of swine waste is limited. In this study, we used 454/GS-FLX pyrosequencing to assess bacterial, archaeal, and fungal composition within a surface flow constructed wetland to determine their spatial dynamics and contaminant removal within the wetland. The results were analyzed using UniFrac coupled with principal coordinate analysis (PCoA) to compare diversity, abundance, community structure, and specific functional groups of bacteria, archaea, and fungi in different sections of the wetland. PCoA analysis showed that bacterial, archaeal, and fungal composition were significantly different (P < 0.001) for the influent compared to the final effluent. Our results showed that the wetland system contained relatively higher proportions of bacteria and fungi than archaea. Most of the bacteria and archaea that are associated with nitrogen removal were affiliated with Nitrosomonas which are ammonia oxidizing bacteria (AOB), Candidatus Solibacter, an anaerobic ammonia oxidizing bacteria (Anammox), as well as Nitrosopumilus, ammonia oxidizing archaea (AOA). The detection of AOB, Anammox, and AOA in this wetland using pyrosequencing shows a spatial display of both abundance and diversity of these groups of bacteria and archaea that are responsible for most of the nitrification processes in constructed wetlands.