PS 29-168 - An environmental DNA (eDNA) analysis of microscopic communities of freshwater ponds to uncover drivers of community composition

Tuesday, August 8, 2017
Exhibit Hall, Oregon Convention Center
Seth Wollney, Biology, College of Staten Island - CUNY, Staten Island, NY and Eugenia Naro-Maciel, New York University, New York, NY
Background/Question/Methods

Freshwater ponds provide important ecosystem services such as nutrient cycling and pollution capture, especially in altered urban landscapes. Despite the value of ponds, the drivers of community membership and structuring, which control ecosystem function and services, within this habitat remain understudied using the powerful new tool offered by environmental DNA (eDNA). eDNA allows censusing of formerly undetected microscopic organisms which allow ecologists to gain a better understand of the impacts of human activities on pondss. The objectives of this work are to test how factors such as season (spring v summer), water quality parameters (nitrate and phosphate, pH and temperature) and physical habitat (sediment type, pond age, surface area) impact community composition. A second objective is to test if constructed but passively restored ponds at Freshkills Park (formerly Fresh Kills Landfill) differ from nearby natural ponds. This study uses two genetic markers, 16S and 18S, to census microscopic biodiversity in seven ponds on Staten Island, NY during spring and summer seasons. Two liters of water were filtered from each pond and genetic material isolated with MoBio PowerWater kits. Samples sequencing on Illumina MiSeq and analyzed with the QIIME pipeline. OTUs were assigned at the 3% dissimilarity threshold.

Results/Conclusions

PERMAVONA test were used to test for compositional difference between sites and identify the influence of associated environmental parameters leading to community dissimilarities. Preliminary results suggest that physical attributes such as location, pond age and sediment type have stronger influence on structuring microscopic organism communities than season and water quality parameters. Future research should aim to include a greater number of ponds with a wider range of environmental variables and gradients of these factors to uncover the drivers of compositional and functional differences of freshwater ponds in urban landscapes.