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Abstract Tree-derived dissolved organic matter (DOM) comprises a significant carbon flux within forested watersheds. Few studies have assessed the optical properties of tree-derived DOM. To increase understanding of the factors controlling tree-derived DOM quality, we measured DOM optical properties, dissolved organic carbon (DOC) and calcium concentrations in throughfall and stemflow for 17 individual rain events during summer and fall in a temperate deciduous forest in Vermont, United States. DOC and calcium fluxes in throughfall and stemflow were enriched on average 4 to 70 times incident fluxes in rain. A multiway model was developed using absorbance and fluorescence spectroscopy to further characterize DOM optical properties. Throughfall contained a higher percentage of protein-like DOM fluorescence than stemflow while stemflow was characterized by a higher percentage of humic-like DOM fluorescence. DOM absorbance spectral slopes in yellow birch (Betula alleghaniensis) stemflow were significantly higher than in sugar maple (Acer saccharum) stemflow. DOM optical metrics were not influenced by rainfall volume, but percent protein-like fluorescence increased in throughfall during autumn when leaves senesced. Given the potential influence of tree-derived DOM fluxes on receiving soils and downstream ecosystems, future modeling of DOM transport and soil biogeochemistry should represent the influence of differing DOM quality in throughfall and stemflow across tree species and seasons.
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This content will become publicly available on September 17, 2026
Controls on the apparent quantum yield for photomineralization of dissolved organic matter in arctic freshwaters
Sunlight breaks down dissolved organic matter (DOM) in lakes and streams to produce carbon dioxide (a greenhouse gas). The efficiency of this process depends on light exposure, the aromatic content of DOM (i.e., Ar–C), and dissolved iron (Fe).
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- Award ID(s):
- 1754835
- PAR ID:
- 10643559
- Publisher / Repository:
- Environmental Science: Processes & Impacts
- Date Published:
- Journal Name:
- Environmental Science: Processes & Impacts
- Volume:
- 27
- Issue:
- 9
- ISSN:
- 2050-7887
- Page Range / eLocation ID:
- 2755 to 2769
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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