DOI: 10.5061/dryad.mgqnk994c
title: Carbon sequestration in degraded intermountain west rangelands, USA

description: Rangelands are often ignored in the discussion of using management to
 sequester carbon but demonstrating that restoration of vast degraded
 rangelands might pay for itself through carbon credit markets would be a
 significant conservation contribution. The additional amount and
 cost of carbon sequestered was quantified by simulating seeding perennial
 grass and shrub species in sagebrush shrublands dominated by non-native
 annual grass and forb species (NNAGF) compared to doing nothing in a
 485,623 km2 Area Of Interest (AOI) centered around Nevada, USA. Using
 Sentinel-2 satellite imagery, NNAGF cover was mapped across the AOI to
 locate areas dominated by NNAGFs. Spatial state-and-transition simulation
 models with a carbon stock-and-flow sub-model simulated the seeding of
 perennial species in NNAGF-dominated sagebrush shrublands in the Columbian
 Plateau ecoregion (IL Ranch, Nevada), north-central Great Basin ecoregion
 outside the North American Monsoon (TS-Horseshoe Ranch, Nevada), and the
 southeastern Great Basin ecoregion within the North American monsoon (PVMH
 landscape, Utah). The net biome productivity (NBP) and cost per unit area
 of sagebrush shrublands was quantified by simulating restoration of NNAGF
 to perennial vegetation over a 25-year period. The unseeded PVMH
 landscape, IL Ranch, and TS-Horseshoe Ranch were sinks of carbon (i.e.,
 positive NBP) at 84, 9, and 11 g C∙m-2∙yr-1, respectively. About 58% to
 90% of NBP was stored in the soil. The IL Ranch required only small levels
 of seeding and was a small sink of C at 0.71 ± 0.65 g C∙m-2∙yr-1, whereas
 the additional NBP for the seeded PVMH landscape was 19.9 ± 10.6 g
 C∙m-2∙yr-1. When extrapolated to the AOI, the most and least carbon
 stored, respectively, was in Utah (136,132 metric Ton∙yr-1, cost: $287M)
 and the central Great Basin (3,196 metric Ton∙yr-1, cost: $23M). Positive
 NBP values reported here showed that carbon sequestration in sagebrush
 shrublands compares favorably with those of more productive systems in the
 USA and worldwide.
description: To quantity carbon sequestration and the cost of seeding, three
 products were required that formed this study’s three parts: (1) an NNAGF
 cover index map for the Area of Interest (AOI) that allowed the
 identification of areas dominated by NNAGFs that could be seeded; (2)
 estimated net amount of carbon stored per unit area of sagebrush
 shrublands through restoration of NNAGF to perennial vegetation, and (3)
 estimated cost of storing net carbon through restoration of sagebrush
 shrublands per unit area. Achieving the components of the methods required
 that we innovatively bring together past state-and-transition simulation
 models focused on management scenarios from different and widely
 distributed Intermountain West landscapes created by The Nature
 Conservancy and apply carbon stock-and-flow modeling within each of these
 simulation models.  Overview of archived
 data: There are three folders in the archived data:
 <br>(A)  "<strong>AnnSpp_Estimation</strong>"
 is a raster map created in Google Earth Engine from several Sentinel 2
 satellite imageries. This raster map (tiff format) and supporting GIS
 files were rendered in ESRI ARC PRO after download from Google earth
 Engine. <br>(B) (i) 
 "<strong>Carbon_IL&TSHS</strong>" folder
 primarily contains the simulation database
 "<strong>Newmont.ssim</strong>," which requires the
 freeware Syncrosim (Version 2.3.12 or later; downloaded from www.apexrms.com )
 and packages ST-Sim and stsimsf (obtained remotely from within Syncrosim)
 and the input (<strong>Newmont.ssim.input</strong>) and output
 (<strong>Newmont.ssim.output</strong>) folders. The Syncrosim
 database and input and output folders are massive (&gt;6 GB of memory
 compressed). Both input and output folders were created and managed by
 Syncrosim during simulations and should not be tampered with as all
 parameters and data to run the simulations are contained within. The
 Authors have never worked within these folders. The
 <strong>Newmont.ssim</strong> contains simulation scenarios
 for the distinct IL Ranch and TS-Horseshoe Ranch (i.e., the same
 simulation library contains both independent projects. (ii) In addition to
 the simulation database, two folders contain all geotiff rasters (no other
 GIS files) that were uploaded in the Syncrosim database (i.e., already
 uploaded). Geotiff rasters were provided for the IL Ranch project
 (<strong>GIS_IL Ranch</strong>) and the TS-Horseshoe Ranch
 (<strong>GIS_TSHS Ranch</strong>). These geotiff rasters might
 be needed for upload if the simulation is conducted on a server with
 different directory pathway organization than the Cloud server used by
 this project. (iii) A "Results" folder contains all the MS Excel
 files of results and there analyses that were exported from the Syncrosim
 database (i.e., Syncrosim-trained users can reproduce our results and
 never open these files).<br>(C) (i) 
 "<strong>Carbon_PV-MH+IP</strong>" folder primarily
 contains the simulation database
 "<strong>IP+PVMH.ssim</strong>," which requires the
 freeware Syncrosim (Version 2.3.12 or later; downloaded from www.apexrms.com )
 and packages ST-Sim and stsimsf (obtained remotely from within Syncrosim)
 and the input (<strong>IP+PVMH.ssim.input</strong>) and output
 (<strong>IP+PVMH.ssim.output</strong>) folders. Both input and
 output folders were created and managed by Syncrosim during simulations
 and should not be tampered with as all parameters and data to run the
 simulations are contained within. Authors have never worked within these
 folders. The <strong>IP+PVMH.ssim</strong> contains simulation
 scenarios for the PVMH landscape, a single landscape. (ii) In addition to
 the simulation database, a GIS folder named
 "<strong>GIS</strong>" contains all geotiff rasters
 (no other GIS files therein) that were uploaded in the Syncrosim database
 (i.e., already uploaded). These geotiff rasters might be needed for upload
 if the simulation is conducted on a server with different directory
 pathway organization than the Cloud server used by this project. (iii) A
 "<strong>Results</strong>" folder contains all the
 MS Excel files of results and their analyses that were exported from the
 Syncrosim database (i.e., Syncrosim-trained users can reproduce our
 results and never open these files).  
description: Compression software to unzip files.
 ESRI ARC Pro to view/process:  Shapefile of
 the project area Training data points
 The python script Final raster result of
 annual species % cover 
 <em>ST-Sim </em>and<em> stsimsf </em>packages in
 SyncroSim freeware to open and simulate models  (at least Version 2.3.12;
 Daniel et al., 2016; www.apexrms.com). Training and support from www.apexrms.com are
 highly recommended.