automated water sampling

Knowledge graph centered on automated water sampling with 75 nodes and 168 connections. Top connected: climate change, snowpack persistence, groundwater storage dynamics, air temperature, Gothic.

Method synopsis

Autonomous sampling system using osmotic pumps to continuously collect water samples over extended periods for chemical analysis. Tubing inlets placed at different depths collect time-integrated samples that can be sectioned to provide temporal resolution.

Synthesized from method descriptions across 4 papers using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Hidden Processes During Seasonal Isolation of a High-Altitude Watershed (2021), Frontiers in Earth Science. Implementations in other papers (listed below) may differ.

1. Deploy OsmoSamplers in river
   Four OsmoSamplers were placed in the river with tubing inlets sampling different depths: river water (RW) column, sediment water interface (SWI) 4 cm into the hyporheic zone, and at 12 cm into the hyporheic zone. OsmoSamplers contained copper small-bore tubing excluding the inlet placed in the water column which contained Teflon tubing. The sample inlets were fitted with 0.2 μm rhizon filters to exclude detritus or microbes that may alter the chemistry during long-term storage within the sample tubing.
   Quantities: 4 OsmoSamplers total, sampling depths at surface, 4 cm, and 12 cm into hyporheic zoneDuration: November 2017 to September 2018Conditions: Deployed during accessible conditions, operated through winter isolation period
   Equipment: OsmoSamplers, copper small-bore tubing, Teflon tubing, 0.2 μm rhizon filters
2. Collect and preserve water samples
   Water collected and preserved along the tubing retains its authentic chemistry because diffusion is minimal in the small inner diameter tubing and filters at the inlet restrict microbial alteration. The time stamp can be determined because the pumping rate, tubing diameter, external temperature, and strength of osmotic gradient are known. Upon recovery, the tubing is cut into increments and liquid content collected to give a time-integrated sample.
   Quantities: Samples sectioned into 4.5 and 1.5 m lengths to obtain ~5 day resolutionDuration: Continuous sampling over 10-month deploymentConditions: Temperature correction applied based on external conditions
   HOBO Data Logger, sample collection vials

Typical Equipment

• OsmoSamplers
• copper small-bore tubing
• Teflon tubing
• 0.2 μm rhizon filters
• HOBO Data Logger

Output Measurements

• dissolved methane concentrations
• sulfate concentrations
• chloride concentrations
• stable water isotopes

Papers Using This Protocol (4)

Species Studied With This Protocol

Places Where Used