I surveyed macroinvertebrate assemblages in ponds in three grazing regimes (ungrazed, rotationally grazed, and continuously grazed) in spring and summer of 2019 on the Osage Plains ecoregion of Missouri. Total suspended solids, turbidity, and organophosphates were lower in ungrazed ponds than in both grazed treatments, and water transparency and aquatic macrophyte cover was significantly higher. Richness was positively correlated with average depth, deepest depth, and water transparency and negatively correlated with turbidity and organophosphate levels. Overall, ungrazed ponds supported higher taxa richness and diversity across all taxa, as well as higher Diptera: Chironomidae, Odonata, and Trichoptera richness. Ungrazed ponds contained 29 unique genera and three unique families compared to two unique genera and two families in rotationally grazed ponds, and one 6 unique genera and one family in continuously grazed units. PerMANOVA results confirmed differences in habitat variables between ungrazed treatments and both grazed treatments; PCA analysis indicated that decreased taxa abundances were mostly associated with nitrate, bank slope, temperature, and pH and, while transparency and vegetation (emergent and cattails) were associated with increased abundances. PerMANOVA results confirmed seasonal differences in ungrazed ponds and continuously grazed treatments for total taxa and families. Chironomid communities differed between treatments and between seasons for ungrazed ponds and both grazing treatments. Fish presence reduced abundance of total taxa across seasons and in spring and Chironomidae taxa across seasons.
| Identifer | oai:union.ndltd.org:unt.edu/info:ark/67531/metadc2356233 |
| Date | 07 1900 |
| Creators | Mittelhauser, Jennifer |
| Contributors | Atkinson, Sam, Goven, Art, Tiwari, Chetan, Poulton, Barry |
| Publisher | University of North Texas |
| Source Sets | University of North Texas |
| Language | English |
| Detected Language | English |
| Type | Thesis or Dissertation |
| Format | Text |
| Rights | Public, Mittelhauser, Jennifer, Copyright, Copyright is held by the author, unless otherwise noted. All rights Reserved. |
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