New Label Style!

Some recent updates to SoilWeb. New visualizations will be incorporated into SoilWeb soon.

Users of our Google Earth interface to USDA-NCSS soils information will now see links to soil-landscape block diagrams listed within map unit descriptions.

Automated Linking to NCSS Block Diagrams

A map depicting the spatial distribution of a given soil series can be very useful when working on a new soil survey, updating an old one, or searching for specific soil characteristics. We have recently added a soil series query facility to SoilWeb, where results are returned in the form of a KML file. Two modes are currently supported:

1. map unit based querying- only map units named for the given soil series are returned
2. component based querying- map units containing components named for the given series are returned

For example, if someone was interested in the spatial distribution of the Amador soil series, they could use the Series Extent Mapping tool to get a quick description of which survey areas contain (and how many corresponding acres of) this series. For an even more detailed description of where the Amador series is mapped, one could use our new soil series query like this:

http://casoilresource.lawr.ucdavis.edu/soil_web/reflector_api/soils.php?what=soil_series_extent&q_string=amador

 
This is a preliminary version, and a subsequent post will contain links to a Google Earth file that can be used to simplify the query process. In most cases queries take about 1-5 seconds, which is quite fast considering: 1) either 730k component names or 275k map unit names are searched, 2) 35 million map unit polygons are filtered for the series in question, and, 3) bounding boxes for matching polygons are merged together-- all on-the-fly. Full text searches for map unit/component names are very fast thanks to advanced text indexing and searching algorithms implemented in PostgreSQL and spatial processing functions implemented in PostGIS. In the final version, the location of the official series description (OSD) will be included in query results.

Attached at the bottom of the page is a KMZ demo showing sample output from the two query modes. Screen shots from the demo are posted below.

Soil Series Query Results: Amador Series: blue regions: map units dominated by the Amador series; red regions: map units that contain at least one component of the Amador series.

SoilWeb is an interactive, multifaceted interface to USDA-NCSS soil survey information. Our SoilWeb application for Google Earth streams soil map units and point data as you navigate across the lower '48 states. Currently, our system imposes a 30,000 ac. limit (defined by the Google Earth viewport) for streaming detailed soil survey (SSURGO) map unit boundaries. This limit, combined with a 2 second delay before streaming is initiated, helps to reduce CPU load on our server. When viewing landscapes from directly overhead the 30,000 ac. limit is usually sufficient for most soils investigations. However, tilting the camera for oblique views of the landscape (an excellent way of visualizing soil-landscape relationships) causes the viewport to encompass much larger areas, usually exceeding SoilWeb's limit for detailed linework. The solution to this problem is summarized below, and can also be used to save "chunks" of detailed soil survey information for later use or offline browsing.

 
Core Functionality

• sync SSURGO data with recent snapshot from SDM
• sync STATSGO data with recent snapshot from SDM

Working on some new ideas on how map unit data can be summarized on small screens-- particularly for our mobile version of SoilWeb. The distance from the nearest map unit polygon boundary is now printed above mini soil profile sketches. This gives the user a little more information that can be used to judge a relative degree of confidence in the returned soils data; the closer you are to the boundary the less likely you are actually standing in displayed map unit.

 
Here is an example:

I found some of the original notes on what I envisioned our online soil survey interface would someday look like.

GE SoilWeb Demo

The folks in Lincoln recently changed the links to the OSDs from http:// to https:// style URLs... which seems to cause problems for new versions of Google Earth. I have noticed that when clicking on soil profile sketches an error is returned (something about an SSL handshake problem). This can be fixed by asking Google Earth to use an external browser for displaying data. Here are some instructions: