About Isee 

The Integrating Spatial Educational Experiences (Isee) web site allows anyone anywhere to access information about the soils, landscapes, and natural and man-made features of Indiana. Isee was originally conceived to support the soil, crop, and environmental science teaching program in the Agronomy Department at Purdue University. Anyone interested in Earth Science, however, is likely to find Isee interesting.

One of the focuses of Isee is on the spatial aspects of soil properties, in other words, how soil properties are distributed over large areas. In the past, soil science has focused primarily on how soil properties vary with depth at specific points in the landscape. Although the concept that soils vary in patterns across landscapes has always been a part of soil science education, teaching students how to understand these patterns was very difficult. Isee allows one to see and understand spatial patterns in the Indiana soil landscape without spending years mapping soils in the field.

Isee consists of maps from different sources, all of which are georeferenced so that each point on each map corresponds to its equivalent latitude and longitude on the Earth’s surface. Below we describe where we obtained the data on which these maps are based and the technical details describing how the maps were created.

Base Map

The underlying base map for Isee is the aerial photography displayed by the Google Earth plugin integrated into the Isee web site. All other maps and overlays are displayed on top of the imagery from Google and Isee has no control over the Google imagery. The source of the Google imagery is displayed at the bottom of the Google Earth window and this text is always on top, even when a map from Isee covers the Google imagery.

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Elevation & TopograpHy

There are 2 maps depicting elevation and topography. Both are based on a high resolution digital elevation model (DEM) derived from the "2005 IndianaMap Digital Elevation Model" data set downloaded from the Indiana Spatial Data Portal.

The original DEM data was available by individual counties at 1.5 m resolution. We resampled the DEM data for each county to 5 m resolution and then combined all counties into one seamless DEM for the entire state. Errors in the original data set were corrected if newer data was available. The state wide DEM was clipped to an outline of the state that was buffered to be 30 meters larger than the state boundary.

From the DEM data, we calculated a hillshade that depicts the topography of the land surface. The hillshade is combined with other data to create many of the other maps in Isee. Many maps, therefore, depict how some property (elevation, dominant soil parent material, natural soil drainage class, land cover, etc.) varies with topography.

The Elevation map in Isee consists of a combination of a transparent elevation map created by applying a color gradient to the DEM data, and the black and white hillshade. The Topography map in Isee consists of the hillshade alone. It is included because the hillshade alone is sometimes necessary to see subtle topographic features.

The locations and elevations of the highest and lowest points in Indiana are from http://igs.indiana.edu/geology/questions/searchFaqsDetail.cfm?FAQ_Number=11

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Soil Properties

The soil properties maps in Isee are all based on digitized soil survey data from the Soil Survey Geographic (SSURGO) database downloaded from the United States Department of Agriculture, Natural Resources Conservation Service, Soil Data Mart. Spatial data was downloaded on February 28, 2009 for each soil survey area in the state. The individual soil survey areas were then combined into one dataset for the entire state. The National Soil Information System (NASIS) was queried on January 26, 2009 to provide the initial tabular data for each soil mapping unit. The soil property maps in Isee therefore reflect the NRCS soil survey data as of February, 2009.

All of the spatial data in the SSURGO database is based on ground observations made over many years of field soil surveys. The original field mapping was usually made on black and white aerial photography at a scale of 1:20,000 or better. Experienced soil surveyors made millions of field observations of soil properties by boring holes to as deep as 5 feet (1.5 meters) to examine the soil. They then recorded their observations by assigning the soil they had just observed to a "soil series" with well defined physical and chemical properties, and by delineating the areas with this type of soil on aerial photographs. We estimate that about 3.5 to 4.0 million individual holes were made during the soil survey of Indiana. There are 1,329,280 individual polygons in the SSURGO soil data set for Indiana, 98.1% of which delineate soil bodies. (The remaining 1.9% delineate bodies of water.) Thus the soil properties maps displayed by Isee are based on one of the highest quality, ground truthed, soil spatial databases in the World.

All maps of soil properties in Isee are combined with the black and white hillshade map. This allows one to see much better how soil properties vary with topography.

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Dominant Soil Parent Material

The Dominant Soil Parent Material map was created by assigning a "dominant" soil parent material to each soil map unit in the state. This was done by examining one or more of the following for each map unit: (1) the official soil series description for the dominant component (soil series) in the map unit, (2) descriptive information for the map unit in the printed soil survey, and (3) the soil parent material(s) assigned to the map unit in the NASIS database. Many soils in Indiana have formed in two, and sometimes even three, distinctly different parent materials. Loess overlying till is common in much of the state, for example. The Dominant Soil Parent Material was considered the parent material with the most influence on other soil properties. In most cases this is the parent material that is deepest in the soil profile. For example, for soils formed in loess overlying till, the till usually has the dominant influence, particularly with respect to determining the Natural Soil Drainage Class. The creation of this map will be documented more fully in the future.

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Natural Soil Drainage Class

This map was created using the Natural Soil Drainage Class for the dominant component in each map unit from data extracted from the NASIS database. There are 7 Natural Soil Drainage Classes in the NASIS database. They are: (1) Excessively Drained, (2) Somewhat Excessively Drained, (3) Well Drained, (4) Moderately Well Drained, (5) Somewhat Poorly Drained, (6) Poorly Drained, and (7) Very Poorly Drained.

The 3 classes that do not have morphological evidence of wetness, Excessively Drained, Somewhat Excessively Drained, and Well Drained, were often used inconsistently from one county to the next. All 3 of these well drained classes have no gray mottles above 30 inches, and the distinction between the classes is an estimate of available water holding capacity rather than the presence or absence of a seasonal high water table. All three were grouped into one Well Drained class, which resulted in considerably fewer abrupt changes in drainage class across county boundaries.

The Very Poorly Drained class was used inconsistently and the following adjustments were made. All map units with muck or mucky in the map unit name were classified as Very Poorly Drained. Most were already classified as Very Poorly Drained and this made them all consistent in terms of drainage class. The Pewamo series was classified as Very Poorly Drained in some counties and Poorly Drained in others. All Pewamo map units with the exception of mucky phases (see above) were classified as Poorly Drained.

Some map units, particularly in urban areas, did not have a Natural Soil Drainage Class recorded. These were placed in the Not Classified class.

All map units in which the dominant component is water are in the Water class.

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Soil Orders

This map was prepared by extracting the soil Order from the classification of the most abundant component in each map unit.

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Fragipans

This map was created by extracting the Fragi- Great Groups or Fragic Subgroups from the classification of the dominant component in each map unit to make the following classes: (1) Shallow Fragipan - all Fragi- Great Groups. (2) Deep or Weak Fragipan - all Fragic Subgroups. (3) Water - the dominant component is water. (4) No Fragipan - all other map units.

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Acidic Subsoils

This map was created by extracting the Ultic Order or Ultic Subgroups from the classification of the dominant component in each map unit to make the following classes: (1) Low Base Saturation - all Ultisols. (2) Moderate Base Saturation - all Ultic Subgroups. (3) Water - the dominant component is water. (4) High Base Saturation - all other map units.

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Surface Colors

This map was created by extracting information from the classification of the dominant component in each map unit and from other information about the map unit to make the following classes: (1) Dark Colored Mineral Soils - all map units in which the dominant component is classified in: (a) the Mollisol Order, (b) in Mollic subgroups of other Orders, or (c) in the Humaquept Great Group, with the exception of Histic Humaquepts. This group also includes map units in which the dominant component is the Door series. (The Door soil has a dark surface, but low base saturation deep in the profile causes it to be classified as an Ultic Hapludalf.) (2) Dark Colored Organic Soils - All map units in which the dominant component is classified in: (a) the Histosol Order, or (b) in a Histic Subgroup. Histic Humaquepts are the only Histic Subgroup in Indiana. (3) Water - the dominant component is water. (4) Light Colored Mineral Soils - all map units which do not meet the requirements for the groups above.

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Land Cover 2001

The data for this map is from the National Land Cover Database 2001 and was downloaded from the Multi-Resolution Land Characteristics Consortium (MRLC) website. The categories, land cover legend, and color scheme were retained from the original data set. For more information see http://landcover.usgs.gov and http://www.mrlc.gov/nlcd.php.

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Geology

Bedrock Geology

The data for this map is from the BEDROCK_GEOL_MM48_IN dataset downloaded from the IndianaMap. Metadata is available here. The ages for the geologic time scale are from the U.S. Geological Survey.

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Historic Maps

S. D. King’s 1852 Map of Indiana

This map was downloaded in digital form from the Library of Congress website. The original map was in 6 parts, each 53 x 59 cm in size. These 6 parts were georeferenced to the intersections of the township and range lines of the Public Land Survey System used to survey much of the state and then combined into one seamless map.

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Dominant Parent Soil Material
Map of the dominant parent soil materials in Indiana.