SOCMA: Soil Organic Carbon in MA

Massachusetts now has statewide land cover-adjusted soil organic carbon (SOC) maps that support carbon-informed land use decisions.

See the Final Report

Download the desktop GIS-ready layers below to view current SOC stocks and compare them with potential SOC under an optimal land cover scenario.

Download GIS Layers [ZIP]
via Google Drive

Last updated: January 2, 2026

What’s included

This download includes:

  • The SOCMA Final Report [PDF]
  • Landcover SOC Conversion Table [CSV]
  • Map Unit Landcover SOC Result Metadata [GPKG]
  • Readme GIS data Soil Organic Carbon SOCMA 251203 [PDF]
  • Desktop GIS-ready layers for:
    • Current SOC (estimated under existing land cover)
    • Potential SOC (estimated under optimal land cover)
    • Three depth intervals: 0–30 cm, 0–100 cm, and full soil profile

How to use the layers

In ArcGIS Pro / QGIS:

  1. Download and unzip the file
  2. Drag the layer file into your map, or use Add Data

Example view: current vs potential SOC outputs across three depths (Northampton oxbow region). Values shown in metric tons per acre.

About the dataset

These layers were developed for Land Cover-Adjusted Soil Organic Carbon Mapping for Massachusetts, funded by the Massachusetts Healthy Soils Initiative. The maps integrate USDA-NRCS SSURGO soils data with 2016 Massachusetts land cover to estimate SOC density at 1-meter resolution across the state.

Use notes and limitations

Please note:

  • These layers represent modeled estimates, not direct field measurements at each location.
  • The analysis uses SSURGO data collected across multiple decades combined with 2016 land cover, which introduces temporal uncertainty.
  • Conversion factors may not apply in every context (for example, wetlands are treated as a special case).

Contact

Questions or troubleshooting help: Contact Regenerative Design Group

Massachusetts Healthy Soils Initiative

This project was funded by the Massachusetts Healthy Soils Initiative, which is administered by the Massachusetts State Commission for Conservation of Soil, Water & Related Resources, the coordinating body for soil and water conservation programs throughout the Commonwealth, and staffed by EEA’s Division of Conservation Services.