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This dataset contains species abundance data of epilithic diatoms collected from the Upper Kuparuk River, Alaska (USA), spanning from 1997 to 2022. The dataset is part of a long-term study aimed at understanding the ecological impacts of phosphorus enrichment in Arctic freshwater ecosystems. Samples were collected annually from the river to examine if physical, chemical, biological, weather, and climate variables influence diatom community composition over time. The dataset includes detailed records of diatom species identified and their relative abundances ins the reference reach only. Analyses of this dataset using permutational multivariate analysis of variance (PERMANOVA), canonical correspondence analysis (CCA), and partial canonical correspondence analysis (pCCA) . Analyses reveal significant shifts in diatom community composition over time, closely linked to changes in alkalinity, nitrate + nitrite, total dissolved phosphorus, dissolved organic carbon, and wind speed. We identify specific diatom taxa as bioindicators, highlighting their sensitivity to shifts in alkalinity, nitrate + nitrite, and wind speed. This dataset provides valuable insights on how climate change is reshaping the structure and function of Arctic rivers, underscoring the importance of diatoms as bioindicators in Arctic ecosystems. It serves as an important resource for researchers studying nutrient dynamics, ecological monitoring, and the impacts of climate change on Arctic freshwater systems.
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Species Abundance Counts of Benthic Diatoms in Response to Phosphorus Fertilization: Data from the Upper Kuparuk River Experiment (UKRE), Alaska, 1997-2022
This dataset contains species abundance data of epilithic diatoms collected from the Upper Kuparuk River, Alaska (USA), spanning from 1997 to 2022. The dataset is part of a long-term study aimed at understanding the ecological impacts of phosphorus enrichment in Arctic freshwater ecosystems. Samples were collected annually from both phosphorus-fertilized and reference reaches of the river to assess the influence of nutrient enrichment on diatom community composition. The dataset includes detailed records of diatom species identified and their relative abundances in the phosphorus reach only. Analyses of this dataset using permutational multivariate analysis of variance (PERMANOVA) and Redundancy Analysis (RDA) revealed significant shifts in diatom communities attributable to phosphorus enrichment. Indicator Species Analysis identified key diatom species that are reliable indicators of phosphorus-enriched conditions. This dataset provides valuable insights into the long-term responses of diatom communities to nutrient enrichment and the ecological interactions with mosses that colonized the fertilized reach. It serves as an important resource for researchers studying nutrient dynamics, ecological monitoring, and the impacts of climate change on Arctic freshwater systems.
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- Award ID(s):
- 2220863
- PAR ID:
- 10573993
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Arctic Diatoms Species Abundance Upper Kuparuk River Phosphorus Enrichment Long-Term Ecological Resarch
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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