Data associated with Lark et al. 2020: U.S. cropland conversion (2008-16)

Maps of cropland conversion classes, year of conversion, and pre- and post-conversion land cover associated with Lark et al. (2020). This repository also includes maps of 'local' and 'national' yield differentials for corn, soybeans, and wheat that are associated with the same publication. Code used to generate these data can be found here.

• Lark, T.J., S.A. Spawn, M.F. Bougie, H.K. Gibbs. Cropland expansion in the United States produces marginal yields with disproportionate costs to wildlife. Nature Communications (In review)

Cropland conversion maps are included in a zipped ESRI Geodatabase titled "US_land_conversion_2008-16.gdb". Each feature layer encompasses all of the conterminous United States at a 30m spatial resolution. Feature layers include:

• mtr = "Multi-temporal results"; Classifies land as being one of five broad land use change classes during the 2008-16 study period:
  1. "stable non-cropland" -- areas of consistent non-cropland throughout the duration of the study period.
  2. "stable cropland" -- areas of consistent cropland throughout the duration of the study period.
  3. "cropland expansion" -- areas converted to crop production between 2008 and 2016.
  4. "cropland abandonment" -- areas converted away from crop production between 2008 and 2016.
  5. "intermittent cropland/confusion" -- areas that were cropped for at least two years but show no clear trend towards or away from cropland. These could include areas under a crop-pasture rotation, fallow rotations, or simply areas with repeated classifier confusion. 
• ytc = "year to cropland"; Indicates the year in which pixels with an mtr classification of "3" (i.e. "cropland expansion") were converted from non-cropland to cropland. e.g., a value of 2009 represents land that was converted between the 2008 growing season and the 2009 growing season.
• yfc = "year from cropland"; Indicates the year in which pixels with an mtr classification of "4" (i.e. "cropland abandonment") were converted from cropland to non-cropland. e.g., a value of 2009 represents land that was still cropped in 2008 and no longer cropped during the 2009 growing season.  
• bfc = "before first crop"; Indicates the last land cover class before a non-crop pixel was converted to cropland. Pixel values correspond to the classification schema of the USDA Cropland Data Layer (CDL) as described in the lookup table here.
• fc = "first crop"; Indicates the class of the first crop planted after a non-crop pixel was converted to cropland. Pixel values correspond to the classification schema of the USDA Cropland Data Layer (CDL) as described in the lookup table here.
• bfnc = "before first non-crop"; Indicates the last cropland class of a pixel before it was abandoned to non-crop land cover. Pixel values correspond to the classification schema of the USDA Cropland Data Layer (CDL) as described in the lookup table here.
• fnc = "first non-crop"; Indicates the first non-crop class of a pixel after it was abandoned to non-crop land cover. Pixel values correspond to the classification schema of the USDA Cropland Data Layer (CDL) as described in the lookup table here.

Yield differential maps are included in the "yieldDifferentials.zip" folder as GeoTIFF rasters with a ~10km spatial resolution. Raster values represent relative (%) differences between the representative yields of new croplands (mtr = 3) and those of stable croplands (mtr = 1) planted to that crop within either (i) the larger 10km x 10km gridcell in which those fields are situated ("local" differentials) or (ii) the entire nation ("national" differentials).

• corn_relDiff_local.tif = local yield differential (%) of corn grain.
• corn_relDiff_national.tif = national yield differential (%) of corn grain.
• soy_relDiff_local.tif = local yield differential (%) of soybeans.
• soy_relDiff_national.tif = national yield differential (%) of soybeans.
• wheat_relDiff_local.tif = local yield differential (%) of wheat.
• wheat_relDiff_national.tif = national yield differential (%) of wheat.