Geographic Information Systems

Introduction

A Geographic Information System (GIS) can improve organization and management of data by linking multiple datasets such as tabular, aerial photos, and other digital data to common locational data (See figure below).  This data can be shared between different applications, creating an efficient system for data management to aid in decision making processes.  Data can be presented in not only maps, but also reports, charts and graphs.  However, GIS systems are not just automated decision making systems with automated maps.  They also serve as tools for analysis and querying of data for ecological decision making.  For example, decisions such as the best location for a particular type of vegetation sampling, given a particular slope and a particular aspect, a certain distance from roads for planning of field crew time, and within areas identified for analysis can be made based on querying the spatial datasets that are available for a given area of study.  The finding of mapping stations when returning to study areas for temporally sensitive analysis can be aided by the use of accurate locational data linked to photos of the mapping station, so the location can be identified by more than the staff who installed the datum.  If a link is created to a spatial dataset, this information can be used in the field with a mobile GIS into which linked data can be added when in the field, reducing post-processing after field work is complete.

(from USGS poster on Geographic Information Systems: http://egsc.usgs.gov/isb/pubs/gis_poster/#top)

(from USGS PowerPoint A Data Management Life-Cycle, by David Ferderer, http://proceedings.esri.com/library/userconf/pug01/docs/ferderer.ppt

Program Development

Integration of GIS into network protocol development is essential to long term ecological monitoring. In order to have an efficient GIS system, current datasets must be collected and organized into a data directory structure. This acquisition and organization stage also includes a degree of analysis of the data to determine its origins, accuracy, attributes, currentness and potential uses, as well as documentation of this information in metadata files associated with the data. The acquisition and organization of spatial datasets for the Mojave Desert Inventory and Monitoring Network (MOJN) started full time in March of 2009, and gained speed in July 2009 with the hiring of an SCA intern. Work focused on inventory and acquisition of recent versions of GIS data from network parks and national clearinghouses and includes base cartographic layers, base imagery such as 1 m true color NAIP, and satellite imagery from Landsat, Aster and Modis vehicles. Although the figure above related to data life cycles indicates that data is continually being sought, upgraded and documented, the base cartographic data acquisition, organization and documentation will generally be complete in early 2010. Image acquisition on the other hand will be ongoing as data and space for storage becomes available.

Other aspects of program development which will continue to be developed include map templates and symbology styles for consistent map generation, terrain models created from digital elevation models, metadata templates, as well as various presentation styles such as piecharts and graphs related to spatial data.

Program Activities

GIS program activities will be focused on supporting protocol development for vital signs monitoring, as well as establishment of base geospatial datasets. Protocol support comes in the form of data management and access for developers with minimal connection to network data, generation of protocol report maps and derived datasets such as least cost path analysis and other derived datasets needed for protocol development and implementation, development of field data gathering standards, methods and guidelines, as well as production of remote sensing products such as change detection analysis of land use and land cover. Training is also provided to the ecologists and other staff related to field data gathering and navigation strategies and the use of Global Positioning System receivers and GIS functionality. For more information about GPS use and availablity at the Mojave Desert Inventory and Monitoring Network, please refer to the MOJN Field GIS/GPS webpage.

Remote sensing consists of the acquisition of information about physical objects and the environment by recording and interpreting imagery and digital representations of energy patterns reflected off of those features by sensors which are not in contact with the feature. For additional information related to remote sensing projects at Mojave Desert Inventory and Monitoring Network, refer to the MOJN Remote Sensing webpage.

Recent Network GIS Activities

Upcoming Activities

August 2008, MOJN GIS Meeting and Training Information Web Page (click here)