Dataset

Database Code

CF016

Title

Solute dynamics in the hyporheic zone of a headwater stream in Watershed 1 at the Andrews Experimental Forest, 2016-2018

Abstract

This project examined the interactions between stream water and subsurface sediment to quantify how these interactions influenced organic C respiration and dissolved inorganic C (DIC) production in the hyporheic zone of a high-gradient headwater mountain stream draining a forested catchment at the H. J. Andrews Experimental Forest, Oregon, USA. The study used six 2-m long hyporheic mesocosms which were packed with streambed sediment in the spring of 2016. The mesocosms are located at the Watershed 1 (WS1) stream gage and stream water from WS1 has been pumped through the mesocosms continuously since they were first packed through the end of (and beyond) this study in autumn of 2018. The mesocosms were designed around 1-m long 20-cm diameter aluminum pipe segments with sample ports located each meter along the flowpath through each mesocosm – thus sampling at the inlet, at 1 m, and at the outlet which represents the full 2-m long flow path. Sampling was conducted on seven dates between Oct 23 2016 and Aug 27 2018. On two of these dates, only background samples were collected. On the remaining 5 dates, sampling was designed around continuous-injection tracer experiments using both a conservative tracer (salt) and a reactive tracer (various dissolved organic substrates). For background sampling events, samples were generally only collected once. The tracer experiments involved 4 discreet sampling times: 1. pre-injection (under background conditions); 2. early plateau; 3. late plateau, and 4. post-injection (and in one injection experiment, a 5th sample at late-post-injection time). For each round of samples, the mesocosm water temperature, pH, EC, and DO were measured with sensors in a small flow-through cell. Then water samples were collected for laboratory analysis for both DOC and DIC. The median travel time of water through each pipe segment of the 2-m mesocosms was also calculated from the conservative tracer break-through curves.

Keywords

biogeochemistry; hyporheic; carbon cycling

Date begin

2016-10-23

Date end

2018-09-10

Principal Investigator

Steven M. Wondzell

Entities

1. Hyporheic Mesocosm - DOC and DIC concentrations in stream and hyporheic water

1. Hyporheic Mesocosm - DOC and DIC concentrations in stream and hyporheic water - Attribute list

Attribute definitions

COMMENT

Notes from field, laboratory, or QA/QC process for any unusual condition or event

DBCODE

FSDB Database Code

DIC

Dissolved inorganic carbon of collected water sample

DO

Dissolved oxygen concentration in water at time of collection

DOC

Dissolved organic carbon of collected water sample

DUPLICATE

a field duplicate water sample

EC

specific conductance (electrical conductivity) of water at time of collection

ENTITY

Entity number

INJNUM

ID code for each injection experiement or background sample

INJTIME

sample time based on breakthrough curve from injection experiment

LAB_DUPE_DOC

Dissolved organic carbon in a laboratory duplicate from the collected water sample

MESOCOSM

Name of hyporheic mesocosm

MESODISTANCE

water tavel distance through the mescocosm

PH

pH (hydrogen concentration) of water at time of collection

RUN

injection experiment name or background sample

SAMPLE_DATETIME

date and time of sample collection (some times are estimated)

SAMPLE_ID

Unique identifier for every sample (a concatenation of injnum, injtime, mesocosm, mesodistance, duplicate)

SITECODE

Gaging station site code

TEMP

Temperature of water at time of collection

TRAVELTIME

Median travel time of solutes through each pipe segment comprising each hyporheic mesocosm

TREATMENT_TYPE

type of injectate used in the injection experiment

Enumerated domains

Enumerated domain for attribute: DBCODE

Enumerated domain for attribute: SITECODE

Enumerated domain for attribute: RUN

Enumerated domain for attribute: INJNUM

Enumerated domain for attribute: INJTIME

Enumerated domain for attribute: MESOCOSM

Enumerated domain for attribute: TREATMENT_TYPE