SOILS – The regolith or surface materials of the landscape support the growth of plants. Soil maps are perhaps the most serviceable in beginning GIS applications.
The attribute tables for soil information is generally clear, and have a structure that can easily be directed in GIS to produce very practical maps such as:
Value added depth to bedrock maps are estimates of soil thickness above bedrock affecting:
- The cost of building foundation construction.
- The cost of roadbed construction.
- The vegetative diversity.
The indirect visual character.
Value added depth to watertable map estimate the soil thickness above ground wholly saturated with water affecting:
- The cost of building construction.
- The cost of road construction.
- The vegetative vigor and diversity.
Value added soil texture (soil class) maps incorporate the unified soil classification system by segregating soil components into sand, silt, clay divisions. This classification system is useful in determining:
- Appropriateness for building materials.
- Material incorporation potential within the construction process.
Value added engineering constraints maps delineate negative characteristics of land and water features that can / might / will affect the planning phase of engineering. Engineering constraints maps influence the construction process and help determine the relative difficulty associated with the actual construction costs.
Value added availability for construction materials sources of on-site (or nearby) construction materials such as topsoil, sand & gravel, and road fill. These maps help reduce overall costs and provide for secondary opportunities in visual amenities, recreational opportunities, and wildlife habitat.
Value Added Soil Association Maps
The USDA (SCS) Soil Surveys include many useful Soil Attribute Tables that can be directly organized and coded to reveal a number of important characteristics about the land in the area.
Example characteristics are color coded to demonstrate:
- Locations for Septic Tank Fields
- Conditions are favorable for Septic Drain Fields
- Soil moisture is retained longer in these areas.
- Areas where flooding is possible (or probable).
Depth to Water Table
- Depth to seasonally average ground water.
Web Soil Survey (WSS) provides soil data and information produced by the National Cooperative Soil Survey. It is operated by the USDA Natural Resources Conservation Service (NRCS) and provides access to the largest natural resource information system in the world. NRCS has soil maps and data available online for more than 95 percent of the nation’s counties and anticipates having 100 percent in the near future. The site is updated and maintained online as the single authoritative source of soil survey information.
These days the information we need is provided digitally – https://websoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx
Rapides Parish, Louisiana – Township 1 N, Range 2 W, Section 28