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Fragment Modifier Calculator

    The Fragment Modifier Calculator is an Excel spreadsheet allowing the user to generate the textural fragment modifier based on percentages of fragments and parafragments. This calculator is from the [National Soil Survey Handbook Part 618, Subpart B, Exhibit 618.90](https://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=29282.wba).

    Soil Texture Calculator

      The Soil Texture Calculator web tool allows the user to input sand and clay percentages to obtain the soil texture. An Excel version is also available for download.

      LandPKS (Land Potential Knowledge System): Mobile App for Extension, Land-Use and Project Planning, M&E and On-Farm Research

        **LandPKS** comprises a free modular mobile phone app connected to cloud-based storage, global databases, and models, downloadable from Google Play or the iTunes App Store; a system for storing and accessing user data; and a system for sharing data, information and knowledge. LandPKS is being developed to help users determine the sustainable potential of their land, including its restoration potential, based on its unique soil, topography and climate. The land potential assessments will be updated based on new evidence regarding the success or failure of new management and restoration systems on different soils.


          Estimates water retention, saturated and unsaturated hydraulic conductivity from basic soil data (requires 32-bit Windows).

          Data from: Soil organic carbon and isotope composition response to topography and erosion in Iowa

            The dataset includes topographic information, soil properties, and 137Cs levels collected from a 15 ha cropland under soybean/maize (C3/C4) rotation in June 2002. The cropland is located in the central-western part of the Walnut Creek watershed, Story County, Iowa. 128 sampling locations were collected and three soil samples were obtained using a 3.2 cm-diameter push probe from the 0 to 30 cm soil layer within a 1 m × 1 m quadrat at each sampling location. Deeper soil samples were collected from 30 to 50 cm layers in locations where sediment deposition was observed. The three samples from each sampling location were mixed and analyzed to determine soil properties, SOC content and its carbon (C) isotope composition (C12 to C13 ratio), and 137Cs levels. For landscape topography of each sampling location, topographic metrics were derived from a digital elevation mode using LiDAR (Light Detection and Ranging) data. These data are useful in investigating the fate of eroded SOC in croplands and its responses to landscape topography.