Topic 4, Module 10: Field Indicators of Hydric Soils in the United States

The module focuses on using the NTCHS Indicators of Hydric Soils (Version 7.0) for onsite decision making about soils in the field. This module share what resources you will need to use the indicators, how to access the electronic resources (including guides, errata sheets and more). The module will help participants understand the definitions of key terms for this work, as well as show how to combine the use of these resources effectively to aid decision making in the field. This module brings together many of the main concepts from earlier modules (e.g.

Topic 3, Module 9: HGM and Hydric Soils

The module focuses on the Hydrogeomorphic (HGM) system and hydric soils. The classification of wetlands in the HGM system is based on landscape position, dominant water source, and hydrodynamics – the magnitude and direction of water inflow and outflow. Information on these parameters is contained in soils information, which is housed in the Web Soil Survey and the soils database. While HGM interpretations are not provided directly, knowledge of soils attributes can be readily applied to make HGM class and sub-class designations.

Topic 3, Module 7: Landscapes and Hydric Soil

The module focuses on typical hydric soil morphologies associated with major wetland types-tidal marshes, peat bogs, perennially-inundated swamps, mineral soil flats, floodplains, depressions, and slope wetlands. The roles of landscape position, hydroperiod, and hydrodynamics on soil morphology will be emphasized. Soil morphology is impacted by the duration of inundation, and the seasonal vertical fluctuations in water tables.

Topic 2, Module 6: The Hydric Soil Technical Standard

The module focuses on the Hydric Soil Technical Standard. The Hydric Soil Technical Standard (HSTS) provides a quantitative method of determining if a soil meets the definition of a hydric soil. The HSTS can be used to: 1) Identify a soils forming as hydric soils when a field indicator may not be present (e.g. wetland creation sites, problematic hydric soils); 2) Evaluate the current functional status of a hydric soil (e.g. change to hydrology); and 3) Propose changes to hydric soil indicators (e.g.

Topic 2, Module 5: Hydric Soil Functions

The module focuses on wetland functions attributed directly to hydric soils. Functions are the biological, chemical, and physical processes that occur in wetlands. Hydric soils play a direct role in the wetland functions of water retention (short term and long term), sedimentation, carbon sequestration and biogeochemical cycling of nutrients. Due to their capacity to become anaerobic close to the surface, hydric soils support unique plant communities and wildlife habitat unlikely to be found in uplands.

Topic 2, Module 4: Redox Reactions and Redoximorphic Features

This module begins with a review of redox reactions and redoximorphic features. Reduction and concurrent oxidation (redox) are the dominant chemical processes taking place in wetland soils. There are abiological and biological driven redox reactions in wetland soils. The module will focus on the reactions driven by microbial breakdown of organic matter in soils under saturated conditions that lead to unique anaerobic conditions that meet the hydric soil definition of USDA.

Topic 1, Module 3: Describing Soil Color for Hydric Soils Determinations

This module focuses on describing soil color. Soil color and the color patterns in soil can tell you a lot about the soil. It is an especially good indicator of soil wetness and hydric soils. The primary components that give a soil its color are soil organic matter, iron, and the color of soil particles. The Munsell Soil Color System is the standard we use to document soil color. When documenting soil color it is important to note matrix color, mottle colors, and type, location and abundance of mottles.

Topic 1, Module 2: Soil Texture and Structure

This module focuses on two physical soil properties - texture and structure. Soil texture describes the relative proportions of sand, silt, and clay in a mineral soil. In soils where organic matter contents are high (such as hydric soils) organic textural classes or modifiers may be used to describe the soil texture instead. Soil structure describes the naturally occurring arrangement of soil particles into peds or aggregates. The combination of soil texture and structure influences how water is stored and moves through the soil, as well as other soil processes.

Topic 1, Module 1: The five factors of Soil Formation and Horizonation vs. Simple Processes

This module will cover both the five factors of formation and horizonation vs. simple processes. The module presentation will begin with a review of redox reactions and redoximorphic features. Reduction and concurrent oxidation (redox) are the dominant chemical processes taking place in wetland soils. There are abiological and biological driven redox reactions in wetland soils. The session focuses on reactions driven by microbial breakdown of organic matter in soils under saturated conditions that lead to unique anaerobic conditions that meet the hydric soil definition of USDA.