GIS Research & Support Facility

The framework chosen as the base for fish prediction modeling for IAGAP was the National Hydrography Dataset (NHD) produced by the USGS, a nationwide comprehensive collection of information about surface water features. The Iowa Stream Reach (ISR) dataset creation process had three main phases. Pre-processing was conducted at ISU. All 57 HUC 8 watersheds extracted from the NHD were combined and projected to UTM zone 15, NAD83. Geological Survey Bureau (GSB) of the Iowa Department of Natural Resources (IDNR) digitized stream reaches in an area of lower stream network density discovered in northwest Iowa. These densified arcs were merged into the NHD arcs and topology was recreated. Several attributes were assigned to all stream reaches including segment ID. The dataset was also checked for disconnected Analyses Once the requisite statewide data were assembled, the actual gap analysis involved intersecting the GIS layers of NHD stream reaches and predicted fish distributions with land stewardship. These results form the basis of GAP's mission to provide land owners and managers with the information necessary to conduct informed policy development, Predicted Fish Distributions The 157 fish species modeled for Aquatic Gap were predicted to be found in 172,632 km of streams, which is all of the total 178,757 km in the Iowa Stream Reach dataset used for IAGAP minus the streams in two Minnesota watersheds that were excluded from fish ranges. Concerning predicted fish richness at the HUC 8 watershed level, hydrologic units contained from 14 to 111 fish species with a median of 57 species. Stream reaches were predicted to contain from 1 to 95 fish species but reaches with more than 50 species per reach were rare and predominately found in the Mississippi and Missouri Rivers. Conclusions Intensive agriculture, urban development, artificial tile drainage, soil erosion, deforestation, channelization of streams and rivers, and an extensive grid of transportation corridors have reshaped Iowa's landscapes since the beginning of European settlement more than a century ago. The tallgrass prairies that helped develop the state's highly productive soils have been reduced by more than 99 percent and about 95 percent of the once abundant prairie potholes have been drained. Over half of the original forest has been lost and the remainder has been severely fragmented and disturbed. Most of the natural areas that remain have experienced some kind of disturbance by grazing, fire suppression, or drainage. Streams have been subjected to straightening, which can increase water velocity and affects in-stream fish habitat. Public lands in Iowa are limited to approximately 2.10% of the total land area of the state and reaches with a designation of public amount to approximately 3.6% of the total length of streams within the state boundary. This includes areas managed by the Federal Government, Iowa Department of Natural Resources, Iowa Department of Minimum GIS System Required for Data Use All GIS data are either ArcView shapefiles or ArcGIS geodatabases or ArcInfo vector coverages. ArcView 3.3, ERDAS Imagine, ArcGIS and GeoMedia will all be able to display and analyze the vector data available from IAGAP. Only ArcGIS is able to display the geodatabase format.

The Iowa Gap Analysis Project (IA GAP) began in 1997 to identify areas in the state where vertebrate species richness lacked adequate protection under existing land ownership and management regimes.To accomplish this goal, the IA GAP team prepared an assortment of datasets that led to three main pieces of information: -- Iowa vegetation types -- Iowa vertebrate/habitat relationship models for 288 species -- Iowa land stewardship (ownership and management) When the project began, there were few statewide datasets available that provided the type of data needed for this project. Consequently, much effort was devoted to building the previously mentioned key data layers at a sufficiently fine scale and resolution for subsequent analysis. At the completion of the project, these data became freely available, with the intent that they will be used by those responsible for managing the state’s valuable natural resources, and by the public, so that every one can be better informed. With this...

The Iowa Aquatic Gap Analysis Project (IAGAP) began in 2001 to identify areas in the state where fish species richness lacked adequate protection under existing land ownership and management regimes. Another ma in goal of the project was to create fish prediction data for Iowa streams and rivers. To accomplish these goals, the Iowa GAP team prepared an assortment of datasets that led to the creation of three main datasets: Iowa streams and rivers; Iowa fish habitat models for 157 species; Iowa land stewardship (ownership and management). When the project began, there were few statewide datasets available that provided the type of data needed for this project. Conse quently, much effort was devoted to building the previously mentioned key data layers at a sufficiently fine scale and resolution for subsequent analysis. The exception to this statement was land stewardship; it had been created for the terrestrial GAP project. It need ed minimal editing to serve as a dataset for IAGAP. A...

Before the implementation of the Iowa Aquatic Gap Analysis, project coordinators had no sense of the breadth of biological sampling data available for fish. However, it was considered important to have the most extensive biological data set possible. We were able to systematically compile a fish inventory database that we believe satisfies this objective. Other Aquatic GAP projects may find themselves in a similar situation and thus benefit from our approach to compiling a comprehensive biological inventory database. Disciplines Environmental Monitoring | Geographic Information Sciences | Natural Resources and Conservation | Physical and Environmental Geography Comments This report is from GAP Analysis Bulletin 12 (2004). This article is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/cfwru_reports/1

The Iowa Gap Analysis Project (IA GAP) began in 1997 to identify areas in the state where vertebrate species richness lacked adequate protection under existing land ownership and management regimes. To accomplish this goal, the IA GAP team prepared an assortment of datasets that led to three main pieces of information: Iowa vegetation types; Iowa vertebrate/habitat relationship models for 288 species; Iowa land stewardship (ownership and management). When the project began, there were few stat ewide datasets available that provided the type of data needed for this project. Conse quently, much effort was devoted to building the previously mentioned key da ta layers at a sufficiently fine scale and resolution for subsequent analysis. At the completion of the project, these data became freely available, with the intent that they will be used by those responsible for managing the state’s valuable natural resources, and by the public, so that every one can be better informed. With this i...