| Section 1 | Overview | |||
| Originator | Minnesota Board of Water and Soil Resources | |||
| Title | waterosion100 | |||
| Abstract | This data layer represents a general risk score for potential soil erosion on a 0-100 point scale, 100 being the highest risk. Larger values indicate soils that have a higher potential to erode if no conservation practices were in place and overland sheet or rill runoff was present.
A subset of the Universal Soil Loss Equation (USLE) was used to determine potential erosion values. The USLE is a multiplicative equation using the formula A =R x K x LS x C x P where: " A = potential long term average annual soil loss in tons/acre/year. " R = rainfall and runoff factor " K = soil erodibility factor " LS = slope length-gradient factor " C = crop/vegetation and management factor " P = support practice factor The R (Rainfall), K (Soil Erodibility), and LS (Length/Slope) factors were used and calculated based on NRCS spatial and tabular SSURGO soils data, statewide county based climate maps, as well as mathematical formulas based on standard USLE calculations. SSURGO stands for Soil Survey Geographic Database. The crop/vegetation and management factor and support practice factor were not used. This is because there are no reliable statewide spatial data that represent these factors. Although there exist statewide data depicting current cropping practices, there are no statewide data representing current tillage methods (e.g. fall plow, ridge tillage, no-till) or support practice (e.g. cross slope, contour farming, strip cropping) that are required for these calculations. Furthermore these factors are temporal and will therefore shift over time. Since only non-management factors were used, the resulting data layer should be viewed as a "worst-case" scenario, i.e. highest potential soil erosion of bare soil with no mitigating land use practices in place. Although quantitative soils loss numbers (tons/acre/year) may be exaggerated under this model, the resulting data layer is used here in a qualitative, comparative capacity in order to compare the relative differences in soil loss risk between various parts of the landscape. | |||
| Purpose | This layer is one portion of an Environmental Benefits Index with the original intention to rank CRP and other critical lands on multiple ecological benefits simultaneously. | |||
| Time Period of Content Date | 05/01/2009 | |||
| Currentness Reference | Data was calculated from 2009 SSURGO soil polygons | |||
| Progress | Complete | |||
| Maintenance and Update Frequency | None Planned | |||
| Spatial Extent of Data | ||||
| Bounding Coordinates | -97.269142 -91.017070 49.404062 43.438097 | |||
| Place Keywords | Minnesota | |||
| Theme Keywords | ||||
| Theme Keyword Thesaurus | ||||
| Access Constraints | ||||
| Use Constraints | ||||
| Contact Person Information | Aaron Spence,
GIS specialist Minnesota Board of Water and Soil Resources St. Paul, MN Phone: 651.296.0660 Email: aaron.spence@state.mn.us | |||
| Browse Graphic | None available | |||
| Associated Data Sets | EBI300, waterqual100, wildlife100 | |||
| Section 2 | Data Quality | |||
| Attribute Accuracy | Calculated for SSURGO soil polygons (minimum mapping unit of 2-5 acres) | |||
| Logical Consistency | ||||
| Completeness | Statewide where SSURGO polygons exist as of May 2009 | |||
| Horizontal Positional Accuracy | ||||
| Lineage | Dataset copied. | |||
| Section 3 | Spatial Data Organization (not used in this metadata) | |||
| Section 4 | Coordinate System | |||
| Horizontal Coordinate Scheme | ||||
| Horizontal Datum | NAD83 | |||
| Horizontal Units | Meters | |||
| Cell Width | 30.000000 | |||
| Cell Height | 30.000000 | |||
| Section 5 | Attributes | |||
| Overview | ||||
| Detailed Citation | ||||
| Table Detail: | ||||
| Section 6 | Distribution | |||
| Publisher | Minnesota Board of Water and Soil Resources | |||
| Publication Date | ||||
| Contact Person Information | Aaron Spence,
GIS Specialist Minnesota Board of Water and Soil Resources St. Paul, MN Phone: Email: aaron.spence@state.mn.us | |||
| Distributor's Data Set Identifier | Downloadable Data | |||
| Distribution Liability | THE GIS DATA ARE PROVIDED TO YOU AS IS AND WITHOUT ANY WARRANTY AS TO THEIR PERFORMANCE, MERCHANTABILITY, OR FITNESS FOR ANY PARTICULAR PURPOSE. The Minnesota Board of Water and Soil Resources does not represent or warrant that the GIS Data or the data documentation are error-free, complete, current, or accurate. You are responsible for any consequences resulting from your use of the GIS Data or your reliance on the GIS Data. You should consult the data documentation for this particular GIS Data to determine the limitations of the GIS Data and the precision with which the GIS Data may depict distance, direction, location, or other geographic features. If you transmit or provide the GIS Data (or any portion of it) to another user, the GIS Data must include a copy of this disclaimer. | |||
| Ordering Instructions | ||||
| Online Linkage | None available | |||
| Section 7 | Metadata Reference | |||
| Metadata Date | 05/12/2011 | |||
| Contact Person Information | ,
, Phone: Email: | |||
| Metadata Standard Name | Minnesota Geographic Metadata Guidelines | |||
| Metadata Standard Version | 1.2 | |||
| Metadata Standard Online Linkage | http://www.gis.state.mn.us/stds/metadata.htm | |||