The Experts below are selected from a list of 72633 Experts worldwide ranked by ideXlab platform
Cynthia A. Stiles - One of the best experts on this subject based on the ideXlab platform.
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The effects of DEM resolution and neighborhood size on digital Soil Survey
Geoderma, 2006Co-Authors: Michael P. Smith, A-xing Zhu, James E. Burt, Cynthia A. StilesAbstract:Terrain characteristics, such as slope gradient, slope aspect, profile curvature, contour curvature computed from digital elevation model (DEM), are among the key inputs to digital Soil Surveys based on geographic information systems (GIS). These terrain attributes are computed over a neighborhood (spatial extent). The objective of this research was to investigate the combined effect of DEM resolution and neighborhood size on digital Soil Surveys using the Soil–Landscape Inference Model (SoLIM) approach. The effect of neighborhood size and DEM resolution on digital Soil Survey was examined through computing the required terrain attributes using different neighborhood sizes (from 3 to 54 m) for 3, 6, 9, 12, 18, and 27 m resolution DEM. These attributes were then compiled and used to digitally map Soils using the SoLIM approach. Field work completed on a hillslope in Dane County, WI in the summer of 2003 was used to validate each of the SoLIM derived Soil Surveys for accuracy. The results of the Soil Survey validations suggest that there is a range of neighborhood sizes that produces the most accurate results for a given resolution DEM. This range of neighborhood sizes, however, varies from landscape to landscape. When the Soils on a gently rolling landscape were mapped, the neighborhood sizes that produced the most accurate results ranged from about 33–48 m. When Soils on short, steep backslope positions were mapped, the neighborhood size values that produced the most accurate results range from about 24–36 m. This paper also shows that it is not always the highest resolution DEM that produces the highest accuracy. Knowing which DEM resolution and neighborhood size combinations produce the most accurate digital Soil Surveys for a particular landscape will be extremely useful to users of GIS-based Soil-mapping applications.
M I Zuberi - One of the best experts on this subject based on the ideXlab platform.
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contrasting approaches to integrating indigenous knowledge about Soils and scientific Soil Survey in east africa and bangladesh
Geoderma, 2003Co-Authors: Robert W Payton, J J F Barr, Adrienne Martin, P Sillitoe, J F Deckers, J W Gowing, N Hatibu, S B Naseem, M M Tenywa, M I ZuberiAbstract:Abstract Methodologies for collection and integration of scientific and indigenous Soils knowledge are discussed in relation to two interdisciplinary projects involving Soil scientists, other natural scientists and anthropologists. In Uganda and Tanzania, participatory methods paralleled scientific Soil Survey. Indigenous or ‘local’ Soil classification was explored by a semi-structured, iterative discussion with farmers, resulting in classes that could be related to scientific taxa. However, the relation of farmers' cognitive Soil maps to scientific Soil maps in the Geographical Information Systems (GIS), developed as an integration domain, was problematic. In-depth analysis was only achieved through geo-referencing local knowledge (LK) using global positioning system (GPS). In Bangladesh, ethnographic methods obtained local Soils knowledge and its socio-cultural context, and accompanied scientific Surveys of floodplain Soils and agroecosystems. Subsequent data processing included database and GIS tools, but there were problems systematically relating the two knowledge bases. The sequencing of, and iteration between, methods used to access and analyse geo-referenced scientific and local Soils knowledge are critical considerations in such research.
Michael P. Smith - One of the best experts on this subject based on the ideXlab platform.
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The effects of DEM resolution and neighborhood size on digital Soil Survey
Geoderma, 2006Co-Authors: Michael P. Smith, A-xing Zhu, James E. Burt, Cynthia A. StilesAbstract:Terrain characteristics, such as slope gradient, slope aspect, profile curvature, contour curvature computed from digital elevation model (DEM), are among the key inputs to digital Soil Surveys based on geographic information systems (GIS). These terrain attributes are computed over a neighborhood (spatial extent). The objective of this research was to investigate the combined effect of DEM resolution and neighborhood size on digital Soil Surveys using the Soil–Landscape Inference Model (SoLIM) approach. The effect of neighborhood size and DEM resolution on digital Soil Survey was examined through computing the required terrain attributes using different neighborhood sizes (from 3 to 54 m) for 3, 6, 9, 12, 18, and 27 m resolution DEM. These attributes were then compiled and used to digitally map Soils using the SoLIM approach. Field work completed on a hillslope in Dane County, WI in the summer of 2003 was used to validate each of the SoLIM derived Soil Surveys for accuracy. The results of the Soil Survey validations suggest that there is a range of neighborhood sizes that produces the most accurate results for a given resolution DEM. This range of neighborhood sizes, however, varies from landscape to landscape. When the Soils on a gently rolling landscape were mapped, the neighborhood sizes that produced the most accurate results ranged from about 33–48 m. When Soils on short, steep backslope positions were mapped, the neighborhood size values that produced the most accurate results range from about 24–36 m. This paper also shows that it is not always the highest resolution DEM that produces the highest accuracy. Knowing which DEM resolution and neighborhood size combinations produce the most accurate digital Soil Surveys for a particular landscape will be extremely useful to users of GIS-based Soil-mapping applications.
Elisabeth N. Bui - One of the best experts on this subject based on the ideXlab platform.
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Soil Survey as a knowledge system
Geoderma, 2003Co-Authors: Elisabeth N. BuiAbstract:Soil Survey leads to the publication of Soil maps and textual reports to communicate the knowledge gained by the Surveyors. The argument that Soil maps and their legends are representations of structured knowledge is made and discussed with some examples. An epistemology of Soil Survey is outlined. The relationship between the mental model of a Soil Surveyor, a Soil map legend, and a Soil map is formally represented. An analogy between knowledge engineers and Soil scientists is made to understand how artificial intelligence, logic, and its formalism can be used in Soil Survey. Some frameworks for presenting Soil Surveyors' mental models explicitly are suggested to improve Soil Survey reporting in the 21st century.
Dylan Beaudette - One of the best experts on this subject based on the ideXlab platform.
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An iPhone application for on-demand access to digital Soil Survey information.
Soil Science Society of America Journal, 2010Co-Authors: Dylan Beaudette, A. T. O'geenAbstract:The mission statement of the National Cooperative Soil Survey (NCSS) emphasizes the importance of information delivery in widely accessible and relevant formats. This aspect of the mission is especially relevant now as the NCSS explores new ways to circulate large and complex geospatial data sets to the public in digital formats. Web-based delivery mechanisms that can simplify the interpretation and delivery of these data are evolving at a rapid pace. The disadvantage of web-based Soil Survey formats is that user access is limited to a computer terminal with an internet connection. We have developed an iPhone application to support on-demand access to Soil Survey information from any location (with cell phone coverage) in the lower 48 states. This application interfaces with our web-based Soil Survey application (caSoilresource.lawr.ucdavis.edu/map; verified 20 July 2010) to extend Soils information in a user-friendly format.
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Soil web an online Soil Survey for california arizona and nevada
Computers & Geosciences, 2009Co-Authors: Dylan Beaudette, Anthony T OgeenAbstract:Digital Soil Survey products represent one of the largest and most comprehensive inventories of Soils information currently available. The complex structure of these databases, intensive use of codes and scientific jargon make it difficult for non-specialists to utilize digital Soil Survey resources. A project was initiated to construct a web-based interface to digital Soil Survey products (STATSGO and SSURGO) for California, Arizona, and Nevada that would be accessible to the general public. A collection of mature, open source applications (including Mapserver, PostGIS and Apache Web Server) were used as a framework to support data storage, querying, map composition, data presentation, and contextual links to related materials. Application logic was written in the PHP language to ''glue'' together the many components of an online Soil Survey. A comprehensive website (http://caSoilresource.lawr.ucdavis.edu/map) was created to facilitate access to digital Soil Survey databases through several interfaces including: interactive map, Google Earth and HTTP-based application programming interface (API). Each Soil polygon is linked to a map unit summary page, which includes links to Soil component summary pages. The most commonly used Soil properties, land interpretations and ratings are presented. Graphical and tabular summaries of Soil profile information are dynamically created, and aid with rapid assessment of key Soil properties. Quick links to official series descriptions (OSD) and other such information are presented. All terminology is linked back to the USDA-NRCS Soil Survey Handbook which contains extended definitions. The Google Earth interface to Soil-Web can be used to explore Soils information in three dimensions. A flexible web API was implemented to allow advanced users of Soils information to access our website via simple web page requests. Soil-Web has been successfully used in Soil science curriculum, outreach activities, and current research projects. Although not the only online Soil Survey application, Soil-Web remains the simplest and most rapid means of accessing Soils information for California, Arizona, and Nevada.
