Collaborative Research: PurSUiT: Aquatic nematodes of the Nebraska Sandhills: Accelerating taxonomic discovery through experiential learning

University Of Nebraska-Lincoln, Lincoln NE

Investigators

Abstract

The Sandhills Region of Nebraska is one of the largest intact temperate grasslands in the world. The landscape of the Sandhills consists of grass-covered sand dunes overlaying the Ogallala Aquifer, a vast underground reservoir that supports diverse communities of plants and animals. The most diverse and abundant animals in the Sandhills are the little known and seldom observed microscopic nematodes. Nematodes have adapted to a wide range of Sandhills habitats, from pristine groundwater-fed streams to alkaline lakes with a water chemistry that restricts most other forms of life. It is unknown what allows nematodes to survive in these extreme environments. However, given the combined effects of climate change and groundwater depletion, the Nebraska Sandhills provide a natural experiment to study the forces that drive diversity and adaptations in this ubiquitous group of organisms. This research will provide insights into how nematodes respond to environmental shifts resulting from the changing climate. Graduate and undergraduate students will engage with a multidisciplinary team of researchers to address these topical questions. Of specific interest to this research are freshwater nematodes in three families (i.e., Tobrilidae, Plectidae, and Monhysteridae) representing three evolutionarily distinct lineages known for their physiological and morphological plasticity but also critical to understanding nematode evolution and phylogeny. There are three main research objectives: 1) describing new species from three targeted nematode families, 2) determining their spatial distributions across the Sandhills, and 3) establishing their taxonomic and ecological context. To accomplish these objectives, three Sandhills regions will be sampled including Alkaline Lakes in Year 1, Sheridan and Cherry Counties in Year 2, and the eastern Sandhills in Year 3 for a total of 128 samples. Samples will be collected from a wide range of aquatic habitats such as lakes, fens/wet meadows, and streams/rivers. Each sample will be split into four aliquots and subsequently used for archiving, individual nematode specimen morphological and barcoding analyses, community metabarcoding and mitochondrial metagenomics, and biochemistry. These data will then be analyzed phylogenetically, and other analyses will include species delimitation, phylogenetic endemism, and multiple regression models and co-occurrence networks. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.