Checking for non-preferred file/folder path names (may take a long time depending on the number of files/folders) ...

Spatiotemporal variability of gas transfer velocity in a tropical high-elevation stream using two independent methods
Authors:
Owners: This resource does not have an owner who is an active HydroShare user. Contact CUAHSI (help@cuahsi.org) for information on this resource.
Type: Resource
Storage: The size of this resource is 6.5 MB
Created: Aug 28, 2025 at 7:17 p.m. (UTC)
Last updated: Sep 17, 2025 at 1:15 a.m. (UTC)
Published date: Sep 17, 2025 at 1:15 a.m. (UTC)
DOI: 10.4211/hs.75a62c0ee4d942d995c96d44bae20a53
Citation: See how to cite this resource
Content types: CSV Content 
Sharing Status: Published
Views: 23
Downloads: 0
+1 Votes: Be the first one to 
 this.
Comments: No comments (yet)

Abstract

Streams in high-elevation tropical ecosystems known as páramos may be significant sources of carbon dioxide (CO2) to the atmosphere by transforming terrestrial carbon to gaseous CO2. Studies of these environments are scarce and estimates of CO2 fluxed are poorly constrained. In this study, we use two independent methods for measuring gas transfer velocity (k), a critical variable in the estimation of CO2 evasion and other biogeochemical processes. The first method, ‘Kinematic k600’ (k600-K), is derived from an empirical relationship between temperature-adjusted k (k600) and the physical characteristics of the stream. The second method, ‘Measured k600’ (k600-M), estimates gas transfer velocity in the stream by in situ measurements of dissolved CO2 (pCO2) and CO2 evasion to the atmosphere, adjusting for temperature. Measurements were collected throughout a 5-week period during the wet season of a peatland-stream transition within a páramo ecosystem located above 4,000m in elevation in northeastern Ecuador. We characterized the spatial heterogeneity of the 250-m reach on five occasions, and both methods showed a wide range of variability in k600 at small spatial scales. Values of k600-K ranged from 7.42 to 330 m d-1 (mean =116 ± 95.1 m d-1), whereas values of k600-M ranged from 23.5 to 444 m d-1 (mean = 121 ± 127 m d-1). Temporal variability in k600 was driven by increases in stream discharge caused by rain events, whereas spatial variability was driven by channel morphology, including stream width and slope. The two methods were in good agreement (less than 16% difference) at high and medium stream discharge (above 7.0 L s-1). However, the two methods considerably differed from one another (up to 73% difference) at low stream discharge (below 7.0 L s-1). Our study provides the first estimates of k600 values in a high elevation tropical catchment across steep environmental gradients and highlights the combined effects of hydrology and stream morphology in co-regulating gas transfer velocities in páramo streams.

Subject Keywords

Coverage

Spatial

Coordinate System/Geographic Projection:
WGS 84 EPSG:4326
Coordinate Units:
Decimal degrees
North Latitude
-0.3229°
East Longitude
-78.1943°
South Latitude
-0.3286°
West Longitude
-78.2003°

Temporal

Start Date:
End Date:

Content

README.md

Spatiotemporal Variability of Gas Transfer Velocity in a Tropical High-Elevation Stream Using Two Independent Methods

Authors: Keridwen M. Whitmore, Nehemiah Stewart, Andrea Encalada, Esteban Suarez, Diego Riveros-Iregui

These authors in italics contributed equally to this work

This repository serves to host data and analyses used in the research supporting the work in:

Whitmore, Keridwen M., et al. "Spatiotemporal variability of gas transfer velocity in a tropical high‐elevation stream using two independent methods." Ecosphere 12.7 (2021): e03647.

Purpose

To provide access to the data and make analyses reproducible for others. All figures presented in the paper were created using R statistical software. Scripts and data files for creating our figures are provided within this repository.

Instructions to run this code

This code was written and run with R version 3.6.2 and R Studio version 1.2.5001. You can download this repository to your local computer and open the project file Whitmore_et_al_2021.Rproj. We use the here package to ensure that the code will run on any computer without having to change any file paths.

Guide to Folders

data

  • File Name: "KatStn1_df.csv"

*these data are used to create figures 3 & 4 *

Column Name: Description

  • DateTime: Date and Time of collection
  • Flux_1: Carbon dioxide flux, unit no 1 (umole per meter squared per sec)
  • airTemp_c: Air Temperature (c)
  • tempC_421: Temperature (c) at station 1
  • stn1_Q: Discharge at station 1 (m3s-1)
  • air_pressure_kPa: Air pressure (kPa)
  • V1_adjusted: partial pressure of CO2 adjusted for temperature and pressure at Station 1 (ppm)
  • CO2_air_ppm: estimated partial pressure of atmospheric CO2 (ppm)
  • air_pressure_atm: Barometric pressure (atm)
  • VaporPressure_atm: Vapor pressure (atm)
  • TotalAir_atm: air pressure as dry air (atm)
  • Total_air_MolperL: air pressure as dry air (moles per Liter)
  • CO2_air_MolesPerLiter: CO2 concentration in air (moles per Liter)
  • CO2_air_gCO2asCPerLiter: CO2 concentration in air (grams of CO2 as C per Liter)
  • WaterTemp_K: water temperature (kelvin)
  • KH_mol.L.atm: Henry's constant (moles per Liter per atm)
  • CO2_water_gCO2asCPerLiter: CO2 concentration in the water (grams of CO2 as C per Liter)
  • deltaCO2_gCO2asCperM3: difference between CO2 concentration in the air and dissolved CO2 concentration (grams of CO2 as C per Liter)
  • Flux_gCO2asCperM2perDay: Carbon dioxide flux, unit no 1 (grams per meters squared per day)
  • k_m.d: gas transfer velocity (meters squared per sec)
  • Sc: Schmidt number
  • K600.effective: measured k600 at station 1 (meters squared per sec)
  • kkin: kinematic K600 label
  • K600.eq1: kinematic k600 at station 1 (meters squared per sec)

__________

  • File: "KatStn4_df.csv"

*these data are used to create supplementary figure 3 *

Column Name: Description

  • DateTime: Date and Time of collection
  • Flux_2: Carbon dioxide flux, unit no 2 (umole per meter squared per sec)
  • airTemp_c: Air Temperature (c)
  • tempC_421: Temperature (c) at station 1
  • stn1_Q: Discharge at station 1 (m3s-1)
  • air_pressure_kPa: Air pressure (kPa)
  • V4_adjusted: partial pressure of CO2 adjusted for temperature and pressure at Station 4 (ppm)
  • CO2_air_ppm: estimated partial pressure of atmospheric CO2 (ppm)
  • air_pressure_atm: Barometric pressure (atm)
  • CO2_air_gCO2asCPerLiter: CO2 concentration in air (grams of CO2 as C per Liter)
  • WaterTemp_K: water temperature (kelvin)
  • KH_mol.L.atm: Henry's constant (moles per Liter per atm)
  • CO2_water_gCO2asCPerLiter: CO2 concentration in the water (grams of CO2 as C per Liter)
  • deltaCO2_gCO2asCperM3: difference between CO2 concentration in the air and dissolved CO2 concentration (grams of CO2 as C per Liter)
  • Flux_gCO2asCperM2perDay: Carbon dioxide flux, unit no 2 (grams per meters squared per day)
  • k_m.d: gas transfer velocity at station 4 (meters squared per sec) |
  • Sc: Schmidt number
  • K600.E.stn4: measured k600 at station 4 (meters squared per sec)

__________

  • File name: PrecipitationData.csv

*these data are used to create Supplimentary figure 1 *

Column Name: Description

  • DateTime: Date and Time of collection
  • ppt_mm: precipitation accumulation at 15 min intervals (mm)
  • ppt24Tot: 24-hour total precipitation (mm)
  • stn1_Q: Discharge at station 1 (m3s-1)

__________

  • File: Synoptic_Kin600.csv

these data are used to create figures 5 & 6

Column Name: Description

  • Date: Date of collection
  • transect: synoptic transect
  • dist.m: distance from outlet (meters)
  • elev.m: elevation (meters)
  • slope.unitless: slope (unitless)
  • depth.m: water depth (meters)
  • velocity.m.s: velocity (meters per sec)
  • Discharge.m3.s: discharge (cubic meters per sec)
  • K600.eq1: kinematic k600 (meters squared per sec)

__________

  • File: Synoptic_Kin600.csv

these data are used to create figures 5 & 6

Column Name: Description

  • DOY: Day of year of collection
  • slope.unitless: slope (unitless)
  • depth.m: water depth (meters)
  • velocity.m.s: velocity (meters per sec)
  • dist.m.AVE: distance from outlet (meters)
  • CO2_ppm: dissolved CO2 concentration (ppm)
  • ave.time: median time of collection during synoptic collection date
  • Synoptic_no: synoptic location sampled
  • Flux_ave_umol_m3_s: Average of 3 Flux measurments collected at sample location (umol per cubic meters per sec)
  • Flux_StdDev: Standard deviation of 3 Flux measurments collected at sample location (umol per cubic meters per sec)
  • WaterTemp_c: water temperature (celcius)
  • Q_m3perS: Average discharge during sample period (cubic meter per sec)
  • air_pressure_kPa: Air pressure (kPa)
  • Date: Date of collection
  • K600.eq1: kinematic k600 (meter squared per sec)
  • air_pressure_atm: Air pressure (atm)
  • VaporPressure_atm: Vapor pressure (atm)
  • CO2_air_MolesPerLiter: atmospheric CO2 (moles per liter) |
  • CO2_air_gCO2asCPerLiter: atmospheric CO2 (grams of CO2 as C per liter)
  • WaterTemp_K: water temperature (kelvin)
  • KH_mol.L.atm: Henry's constant (moles per Liter per atm)
  • CO2_water_gCO2asCPerLiter: CO2 concentration in the water (grams of CO2 as C per liter)
  • deltaCO2_gCO2asCperM3: difference between CO2 concentration in the air and in the water (grams of CO2 as C per m^3)
  • Flux_gCO2asCperM2perDay: Carbon dioxide flux, unit no 1 (grams of CO2 as C per meters squared per day)
  • k_m.d: gas transfer velocity (meters squared per sec) |
  • Sc: Schmidt number
  • K600.effective: measured k600 (meters squared per sec)

__________

__________

scripts

  • Fig3.R R code figure 3
  • Fig4.R R code figure 4
  • Fig5.R R code figure 5
  • Fig6.R R code figure 6
  • SuppFig1.R R code supplementary figure 1
  • SuppFig2.R R code supplementary figure 2
  • SuppFig3.R R code supplementary figure 3

__________

Points of contact

Direct questions about the paper to Dr. Diego Riveros-Iregui: diegori@email.unc.edu

Direct questions about the code to Kriddie Whitmore: kriddie@email.unc.edu

Related Resources

This resource is described by Whitmore, K. M., Stewart, N., Encalada, A. C., Suárez, E., & Riveros‐Iregui, D. A. (2021). Spatiotemporal variability of gas transfer velocity in a tropical high‐elevation stream using two independent methods. Ecosphere, 12(7), e03647.

Credits

Funding Agencies

This resource was created using funding from the following sources:
Agency Name Award Title Award Number
U.S. National Science Foundation 1847331

How to Cite

Whitmore, K. M., D. Riveros-Iregui, N. Stewart, A. C. Encalada, E. Suárez (2025). Spatiotemporal variability of gas transfer velocity in a tropical high-elevation stream using two independent methods, HydroShare, https://doi.org/10.4211/hs.75a62c0ee4d942d995c96d44bae20a53

This resource is shared under the Creative Commons Attribution CC BY.

 http://creativecommons.org/licenses/by/4.0/
CC-BY

Comments

There are currently no comments

New Comment

required