By Lori Armstrong
The World Water Online (WWO) group in the ArcGIS Resource Center has 12 new web map applications based on the SSURGO soil survey database. These apps show soil characteristics that are useful for hydrologic modeling, such as drainage class, available water storage, water table depth, and ponding frequency. The hydrologic group code, which classifies soils based on infiltration rate, can be used to calculate curve number and model how much rain falling in an area will become runoff.
by Rich Nauman, Product Engineer, Esri. Do you need to use soil data in your analysis? Simply open the SSURGO Downloader Application, navigate to your project area, click the map to open a pop-up and then click the download link … Continue reading
by Johnny Sullivan, Graduate Research Assistant, Center for Research in Water Resources, The University of Texas at Austin, email@example.com It is unclear at present exactly how climate change will affect global precipitation patterns on a long-term time scale. The Intergovernnmental … Continue reading
by Michael Dangermond, Senior Digital Cartographer, Esri
The Soil Hydrology of the United States Web Map Application brings some of the most important hydrologic soil properties together in one map. Find hydrologic group codes for hydrologic and hydraulic models. Find hydric soil information to determine wetland land classification. Find depth to the water table for groundwater analysis and well drilling operations.
What is SWAT?
A sophisticated basin-scale computer model that predicts impacts of weather, soils, land use and land management on water supplies and pollution as well as soil erosion, fertility and crop production.
This model contributes to understanding the complex ecosystem and its service to water availability, water quality; food vulnerability and food production; as well as socioeconomic demography issues worldwide.
The Soil and Water Assessment Tool, or SWAT model, is a public domain model developed by a group of scientists from the USDA-Agricultural Research Service; USDA-Natural Resources Conservation Service, and Texas A&M University.
Let’s say you’re a farmer or farm real estate broker, and you are evaluating whether or not to buy a piece of land. Your business and your livelihood depends completely on the land and its capability to produce income.
How do you tell the difference between a bad piece of land and a piece of land that has good potential but hasn’t been managed well or has otherwise been neglected? What can the piece of land do, and what is it really worth?
In a time of great uncertainty and volatility in financial markets and real estate valuation, the inherent capability of a piece of land’s soil asset has just become a lot easier to estimate. Image credit: USDA
To help answer these questions, esri has produced two new maps and map layers on arcgis.com. Both are planning-level maps of the economic capability of the United States’ soils. One map shows the economic capability when the soil is irrigated and the other when the soil is not irrigated. These maps are entitled Irrigated Land Capability Class and Non-Irrigated Land Capability Class, respectively.
Both maps are made directly from the SSURGO planning level soil dataset from NRCS. For the more technical among us, we used the MUAGGATT table fields ICCDCD and NICCDCD from SSURGO. Both maps cover the entire USA including Hawaii, Alaska, and Puerto Rico.
At 1:24,000 scale, each part of the United States falls into one of eight broad land capability classes.
The first four classes (1-4) are useful for growing crops, where each class from one to four needs more management or treatment, and has more limitations than the previous class. For example, classes 3 and 4 require more management or treatment than classes 1 and 2.
The last four land capability classes (5-8) are not useful for crops. NRCS recommends these lands be used for things other than crops, like rangeland, forestland, or wildlife habitat. Class eight isn’t even good for forestry, pasture or rangeland, and so instead NRCS recommends those lands be used for recreation, wildlife habitat, watershed, or aesthetic purposes.
These maps feature a color scheme (shown here in 50% transparency) that matches an image of a sample landscape that you see when you click on each soil map unit. This graphic may then be used like a second legend, displaying the eight classes for you on a replica landscape.
Land Capability Class is one of the most important concepts in the US soil dataset SSURGO. Land Capability Class is even used in some states for property tax assessment. In the State of Ohio, for example, the tax code prescribes specifically how to use this map to determine property tax.
Esri plans to release more land capability maps, specifically Land Capability Subclass. We will let you know as soon as these maps are complete and online, and rest assured that the subclasses will be in a format that is easily mashed up with either the Irrigated or Non-Irrigated Capability Class maps.
Special thanks to Michael Dangermond for providing this post. Questions for Michael: firstname.lastname@example.org
The Soil Survey Map, a new specialty map service available on ArcGIS Online, shows the Soil Survey Geographic (SSURGO) by the United States Department of
Agriculture’s Natural Resources Conservation Service. Learn more about this detailed soils map on the ArcGIS Online Blog.
A new specialty map service, the Soil Survey Map (Soil_Survey_Map), was published recently on ArcGIS Online (services.arcgisonline.com, server.arcgisonline.com). This detailed map shows the
Soil Survey Geographic (SSURGO) by the United States Department of
Agriculture’s Natural Resources Conservation Service. This level of mapping is designed for use by
landowners, townships, and county natural resource planning and management.
user should be knowledgeable of soils data and their characteristics. Farmland class, hydrologic, drainage, and
irrigation data can also be queried on the largest scale soil data layer. The soil units are symbolized by Esri to show
the dominant condition order for the 12 soil orders according to Soil
Taxonomy. These orders include Alfisols,
Andisols, Aridisols, Entisols, Gelisols, Histosols, Inceptisols, Mollisols,
Oxisols, Spodosols, Ultisols, and Vertisols.
There are three
different scale-specific layers in the map service. The largest scale data is derived by SSURGO
as stated above. The mid scale data
layer shows the U.S. General Soil Map of general soil association units by the
United States Department of Agriculture’s Natural Resources Conservation
Service (USDA/NRCS). It was developed by
the National Cooperative Soil Survey and supersedes the State Soil Geographic
(STATSGO) dataset published in 1994. The
small scale data layer shows the Global Soil Regions map also by the United
States Department of Agriculture’s Natural Resources Conservation Service.
If you have questions or feedback, please post them in the ArcGIS