DASIG

Data Automation Software for Calculation of Greenhouse Gas Emissions for Agricultural Crops

The DASIG model is a user-friendly computer application for the calculation and modeling of greenhouse gas (GHG) emissions from agricultural crops. It analyzes, calculates, and verifies the accuracy of nitrous oxide (N₂O), methane (CH₄), and carbon dioxide (CO₂) emissions using air samples collected from vented flux chambers installed in the field.  Air samples collected from multiple chambers at predefined time intervals are processed using a trace gas analyzer, such as a gas chromatograph (GC), so that time series of GHG concentrations can be determined, from which GHG fluxes are estimated.

The DASIG model provides a well-defined workflow that automates and simplifies the calculation of GHG fluxes, allowing non-experts to produce high quality data.  In each step, the model enforces strict quality control procedures defined and periodically updated by the Global Research Alliance on Agricultural Greenhouse Gases.  The model also summarizes both gas sample and analysis data, providing a documented database of results that comply with world-class quality control standards.

DASIG is the Filipino word for Acceleration, in reference to its goal of simplifying and expediting time-consuming GHG emission calculations that require manual data entry and are usually performed with the help of large electronic spreadsheets.

DASIG Purpose and Features

The DASIG model is being developed as a modular software package that employs data analytics techniques, data quality control, and statistical analyses for the calculation of emission fluxes from time series of GHG concentrations.  In its first public release, it supports the data processing pipeline for the static (closed) chamber method coupled with gas concentration data.  DASIG aims at providing convenient tools for:

• Processing of data streams originating from gas analyzer instruments.
• Automated instrument performance verification using standard gases of known concentration.
• Generation and validation of batch-specific GHG concentration calibration curves for increased accuracy.
• Quality control and quality assurance procedures according to the newest scientific standards.
• Calculation and summarization of gas concentrations for emission flux calculations, with enforcement of instrument detection limits.
• Computation of GHG fluxes based on Fick’s law of diffusion using time series of gas concentrations.
• Support of multiple flux calculation models for linear and non-linear concentration-time curves from close chamber measurements.

The DASIG Software

In its initial release, it contains two submodels: the Dasig-Flux model and the Dasig-GWP model, both developed to support GHG measurements in flooded rice using the chamber method.

Dasig-Flux processes data files containing time series of GHG concentrations (determined through gas analyzers) and chamber and environmental parameters to helps users with the identification of gas samples and determination of calibration curves for standard gases. It performs data quality and assurance tests using detection limits and control values and calculates gas fluxes using linear and non-linear equations.

The Dasig-GWP Global Warming Potential module estimates the climate impact of CH₄, N₂O and CO₂ from cropland using data generated by the Dasig-Flux module. It calculates daily, cumulative, and total GHG emissions for given crop growth periods or annual cycles. Emissions are reported in terms of CO₂ equivalents (CO₂ eq) using the latest GWP factors as reported by the Intergovernmental Panel on Climate Change for 20 and 100-year horizons. Dasig-GWP also calculates area-scaled summaries for different crop treatments.

Several other modules are currently under development. The Dasig-Kasoku module processes raw data generated by Shimadzu GC instruments (Models 2014, 2030) and creates a database for further analysis. A first version will soon be added to the DASIG application that will process chromatogram data streams from Shimadzu GC systems.

Other software components are being developed to facilitate data management and analyses of GHG emission measurement campaigns, including a fully integrated user interface, a comprehensive database system, and additional data analysis and quality control procedures. DASIG is entirely programmed in Python, so it can easily integrate with existing data analytic, visualization, and report generation tools. Future versions will gradually introduce new capabilities, such as data sharing and data integration with organization databases.

DASIG Scientific Development 

The scientific development for DASIG’s sampling design, gas concentration determination, emission flux calculations, and quality control protocols were developed to support field research on GHG emissions from flooded rice crops in northeastern Arkansas. Research was directed by the USDA – Agricultural Research Service, in collaboration with the Arkansas State University and the University of Arkansas Division of Agriculture.

For more information on current and planned DASIG’s capabilities or for inquiries about ongoing GHG emission research in cropland, please contact Dr. Arlene Adviento-Borbe, Research Agronomist, USDA-ARS Delta Water Management Research Unit.

DASIG is being developed by

Dr. Arlene Adviento-Borbe, Scientific lead and principal investigator, USDA-ARS.

Soichiro Takahashi, Software Design and Development, Lead programmer, University of Arkansas.

Dr. Dalmo A. N. Vieira, Software System Architecture, Software Design and Data Analytics, Arkansas State University.

DOWNLOAD DASIG

The DASIG application for Windows is available for download from this page. (Coming Soon)