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Abstract Temperate lakes experience variation in mixing and stratification that affects the distributions, activities, abundances, and diversity of plankton communities. We examined temporal and vertical changes in the composition of planktonic microorganisms (including Bacteria and Archaea) in oligotrophic Flathead Lake, Montana. Using a combination of approaches that included 16S rRNA gene sequencing and flow cytometric determination of cell abundances, we found that the microbial community was responsive to variations in stratification and mixing at time scales ranging from episodic (scale of days) to seasonal. However, the impact of such physical dynamics varied among taxa, likely reflecting taxa‐specific responses to environmental changes that coincide with stratification and mixing (e.g., light availability and nutrient supply). During the early spring, periods of relatively short‐term (< 7 d) intermittency in stratification and mixing influenced the vertical distributions of specific microbial taxa, notably including the cyanobacteria. These events highlight time scales of biological responses to high‐frequency variations associated with lake stratification and mixing, particularly during the transition to the growing season in the early spring.
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Phenological shifts in lake stratification under climate change
Abstract One of the most important physical characteristics driving lifecycle events in lakes is stratification. Already subtle variations in the timing of stratification onset and break-up (phenology) are known to have major ecological effects, mainly by determining the availability of light, nutrients, carbon and oxygen to organisms. Despite its ecological importance, historic and future global changes in stratification phenology are unknown. Here, we used a lake-climate model ensemble and long-term observational data, to investigate changes in lake stratification phenology across the Northern Hemisphere from 1901 to 2099. Under the high-greenhouse-gas-emission scenario, stratification will begin 22.0 ± 7.0 days earlier and end 11.3 ± 4.7 days later by the end of this century. It is very likely that this 33.3 ± 11.7 day prolongation in stratification will accelerate lake deoxygenation with subsequent effects on nutrient mineralization and phosphorus release from lake sediments. Further misalignment of lifecycle events, with possible irreversible changes for lake ecosystems, is also likely.
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- Award ID(s):
- 1759865
- PAR ID:
- 10338055
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41467-021-22657-4
