Reducing Sampling Bias Through Continuous Monitoring of CO2 Efflux at NSZD Sites

Recent research has shown that soil carbon dioxide (CO2) efflux can be used to quantify the rate of contaminant degradation – either natural or enhanced – occurring at petroleum hydrocarbon impacted sites. Point sampling programs with traditional flux chambers are currently the status quo for measuring carbon dioxide effluxes in the field, but this approach is problematic for gaining a thorough understanding of Natural Source Zone Depletion (NSZD) rates.  READ MORE

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Evaluating Gas Emission Measurements Using Minimum Detectable Flux (MDF)

Traditional vial-and-syringe-type measurements of closed chamber trace gas fluxes have provided researchers with massive amounts of insight into ecosystems ranging from old growth forests to heavily managed agricultural fields. However, anyone who has ever collected these types of gas samples knows that you can easily compromise your carefully collected samples in the blink of an eye, or with a trip down the stairs. Even if you’re careful, and get your vials back to the lab in one piece, data can still be lost during extraction and analysis. READ MORE

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Sampling using a static flux chamber. Photo: Brett Sattazahn

Biases of Temporally Sparse Data and Measurement Scheduling on Flux Estimates

Estimates of baseline and event-driven greenhouse-gas (GHG) emissions from soils play an increasingly important role in numerous areas, including improving our understanding of ecosystem processes, climate change mitigation and agricultural yields. These emissions vary substantially in their temporal variability, spatial variability and response to periodic and episodic events, not only between different gas species but also across field sites and seasons for a single gas. Despite considerable research on the techniques and best practices for obtaining accurate gas emission estimates, comparatively few studies have examined the effects and possible biases that result from when and how often these measurements are collected. READ MORE

Creelman, C., 2015. Biases of Temporally Sparse Data and Measurement Scheduling on Flux Estimates. ResearchGate. DOI: 10.13140/RG.2.1.3797.1280

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Example of static soil flux chamber (USDA)

Sizing Solar Power for Off­-grid Field Studies

Selecting a solar panel, charge controller, and battery suited to supply power to a remote data collection site can be a challenging task, even for an experienced user. One of the problems is that most of the guides available for selecting photovoltaic (PV) solar power options assume that it is a permanent installation for a home or business rather than a temporary, unmanned installation. With this article, we hope to present some of the challenges and solutions to providing reliable power for autonomous field stations. READ MORE

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Reading sun angles -

Reading sun angles from