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Abstract. Air–water gas exchange is essential to understanding and quantifying many biogeochemical processes in streams and rivers, including greenhouse gas emissions and metabolism. Gas exchange depends on two factors, which are often quantified separately: (1) the air–water concentration gradient of the gas and (2) the gas exchange velocity. There are fewer measurements of gas exchange velocity compared to concentrations in streams and rivers, which limits accurate characterization of air–water gas exchange (i.e., flux rates). The National Ecological Observatory Network (NEON) conducts SF6 gas-loss experiments in 22 of their 24 wadeable streams using standardized methods across all experiments and sites, and publishes raw concentration data from these experiments on the NEON data portal. NEON also conducts NaCl injections that can be used to characterize hydraulic geometry at all 24 wadeable streams. These NaCl injections are conducted both as part of the gas-loss experiments and separately. Here, we use these data to estimate gas exchange and water velocity using the reaRate R package. The dataset presented includes estimates of hydraulic parameters, cleaned raw concentration SF6 tracer-gas data (including removing outliers and failed experiments), estimated SF6 gas-loss rates, normalized gas exchange velocities (k600; m d−1) and normalized depth-dependent gas exchange rates (K600; d−1). This dataset provides one of the largest compilations of gas-loss experiments (n=339) in streams to date. This dataset is unique in that it contains gas exchange estimates from repeated experiments in geographically diverse streams across a range of discharges. In addition, this dataset contains information on the hydraulic geometry of all 24 NEON wadeable streams, which will support future research using NEON aquatic data. This dataset is a valuable resource that can be used to explore both within- and across-reach variability in the hydraulic geometry and gas exchange velocity in streams. The data are available at https://doi.org/10.6073/pasta/18dcc1871ee71cf0b69f2ee4082839d0 (Aho et al., 2024), and the reaRate R package code is available at https://doi.org/10.5281/zenodo.12786089 (Cawley et al., 2024).
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TIERRAS Tracer Injection Experiments in RiveRs And Streams
The TIERRAS project is an open-access platform that compiles a database of more than 400 tracer injection experiments in rivers and streams, sourced from previously published studies and reports. It also includes interactive features that allow users to explore, download, and contribute new data. The goal is to provide a centralized and accessible repository for researchers, environmental managers, and anyone interested in water quality, hydrological modeling, and stream solute dynamics. These experiments were collected from various sources, including published studies, unpublished data, and technical reports from different authors. The original data were in diverse formats and units; all data were curated and standardized to a consistent format and to the Imperial (U.S. customary) units. Visit TIERRAS at https://www.tierras.org/ Cite: Rodríguez, L., Tunby, P., Abusang, A., Tartakovsky, A., Carroll, K., Ginn, T., & González-Pinzón, R. (2025). TIERRAS Tracer Injection Experiments in RiveRs And Streams (2.0) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.15794259
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- Award ID(s):
- 2142691
- PAR ID:
- 10620843
- Publisher / Repository:
- Zenodo
- Date Published:
- Subject(s) / Keyword(s):
- Hydrology Water Quality
- Format(s):
- Medium: X
- Right(s):
- Creative Commons Attribution Non Commercial 4.0 International; Copyright (C) 2025 Lina Rodriguez. Licensed under CC BY-NC 4.0.
- Sponsoring Org:
- National Science Foundation
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