Assessing the hierarchy of long-term environmental controls on diatom communities of Yellowstone National Park using lacustrine sediment records

Abstract

Chraïbi VLS, Fritz SC. 2020. Assessing the hierarchy of long-term environmental controls on diatom communities of Yellowstone National Park using lacustrine sediment records. Lake Reserv Manage. 36:278–296.

An ecosystem’s ability to maintain structure and function following disturbance, defined as resilience, is influenced by a hierarchy of environmental controls, including climate, surface cover, and ecological relationships that shape biological community composition and productivity. This study examined lacustrine sediment records of naturally fishless lakes in Yellowstone National Park to reconstruct the response of aquatic communities to climate and trophic cascades from fish stocking. Sediment records of diatom algae did not exhibit a distinct response to fish stocking in terms of assemblage or algal productivity. Instead, 3 of 4 lakes underwent a shift to dominance by benthic diatom species from 1935 to 1950, which suggests lower lake levels resulting from warmer, drier climatic conditions. The lake that did not undergo such a shift is fed by groundwater rather than snowmelt, suggesting a buffering effect by water source. Dissimilarity analysis shows that the diatom assemblages in all 4 lakes have become increasingly dissimilar since circa 1955, suggesting that communities have not yet stabilized from the first-order influence of climate. Thus, climate likely had a more prominent influence on diatom community structure than did manipulation of the fish community. Understanding the relative importance and interplay among abiotic and biotic stressors and the resultant resilience of an ecosystem provides implications for the adaptive management of lakes.

Keywords:

• Climate change
• diatoms
• fish stocking
• paleolimnology
• resilience
• trophic cascade
• Yellowstone National Park

Acknowledgments

Dr. Robert Gresswell and Dr. Cathy Whitlock provided valuable insight into study site selection. We also thank Dr. Gresswell for providing historical records of fish stocking and giving valuable feedback on the article. Dr. D. Marie Weide, James Benes, and Dave Mosicki assisted with field sampling. Sediment ²¹⁰Pb dating was done under the supervision of Dr. Daniel Engstrom at the St. Croix Watershed Research Station. Snow water equivalent data are courtesy of Dr. Greg Pederson. The site map was produced by Dr. Xavier Benito.

Additional information

Funding

This research was funded by National Science Foundation 10.13039/10000 (NSF) grant EAR-0816576 to S. Fritz and an NSF-IGERT fellowship (0903469), Geological Society of America10.13039/100005720 grants, and a Paleontological Society10.13039/100010841 grant to V. Chraïbi.