Subaqueous soil

Subaqueous soil

Subaqueous Soils are soils that form in sediment found in shallow permanently flooded environments. Excluded from the definition of these soils are any areas “permanently covered by water too deep (typically greater than 2.5 m) for the growth of rooted plants.

The study of subaqueous soils is a relatively new field in Pedology or soil science. The concept that sediments in shallow water environments undergo soil forming processes, are capable of supporting rooted plants (such as Eelgrass), and meet the definition of soil according to the criteria defined in Soil Taxonomy has been moving soil scientists into a new frontier of soil survey – mapping subaqueous soils.

The National Cooperative Soil Survey (NCSS) is a nationwide partnership of Federal, regional, State, and local agencies and institutions. This partnership works together to cooperatively investigate, inventory, document, classify, and interpret soils and to disseminate, publish, and promote the use of information about the soils of the United States and its trust territories. The activities of the NCSS are carried out on National, regional, and State levels.

The USDA, Natural Resources Conservation Service (NRCS) is the lead federal agency for the mapping and interpretations of the nation’s soil resource and the extension of soil survey technology to global applications.

ubaqueous and Submerged Soils

As the name implies, subaqueous and submerged soils are soils that occur under water (both fresh and salt water). The depth range of the water column where these soils may be found is not known, an arbitrary depth of 2.5 meters below the surface has been set for soil survey inventory but some states have extended this depth to 5 m (NAVD 88). The difference between subaqueous and submerged soils is that submerged soils formed in an upland environment then became submerged as a result of rising water tables, flooding events (such as a Beaver Dam), or sea level rise. Subaqueous soils formed under a continuous water column (such as in an estuary), although their sediments may have originated from an upland area such as a dune.

Although proposals to include permanently submersed sediments as soil have been put forth since the mid 1800’s, it was not until the early 1990’s that the concept of subaqueous soils was developed in the U.S. The pioneer in U.S. subaqueous soils is the late George Demas, a soil scientist working for the National Cooperative Soil Survey in the Chesapeake Bay region of Maryland. George observed that subaqueous areas met the definition of soil by being able to support rooted plant growth (such as Eelgrass) and had formed soil horizons. Further study revealed that these submersed sediments underwent other soil forming (pedogenic) processes including additions, losses, and transformations of energy and matter.

ignificance of Subaqueous Soils

A major limitation to science-based management of shallow water habitats has been a lack of definitive information on the properties and spatial distribution of subaqueous soils. In part, this lack of information has stemmed from an inadequate paradigm for subaqueous soils, which has not considered them “soils” at all, but rather as “sediments”. During the decade it has been demonstrated that these “sediments” would be better understood as “soils” and that the sedimentary paradigm should give way to a pedological paradigm.

An advantage of using the pedological approach to study shallow water habitat is that soils are studied as a collection of horizons that are linked vertically with depth and horizontally across the subaqueous landscape. These horizons are studied and characterized by examining a combination of properties and characteristics, instead of, say, a single component or parameter. In this manner, subaqueous soil can be characterized as ecological map units and provide a site-based system to identify the geomorphic settings that represent the subaqueous landscape. The following are some advantages of a subaqueous soil approach to shallow water classification:

# Sediment characteristics presented to a greater depth (2 m), rather than a bottom-type classification (such as mud bottom or rocky bottom).
# Provides a comprehensive classification scheme (Soil Taxonomy, Soil Survey Manual) for shallow water sediments. # Could provide a major or missing data set for submersed aquatic vegetation (SAV) restoration, estuarine protection, planning and management.

ubaqueous Soil Survey

Several States throughout the U.S. have begun the process of mapping and inventorying subaqueous soils. States with subaqueous soils are responsible for determining the activity in their State related to subaqueous soil mapping.

How are subaqueous soils mapped?

Traditional terrestrial soil mapping is conducted by a field soil scientist trained to understand the interaction of soil forming processes and soil-landscape relations. Mapping soil involves mostly field work with the soil mapper traversing the landscape and digging many holes to observe and classify the soil. Subaqueous soil mapping is performed in much the same way, except the mapper is in water. Instead of topographic maps to provide landscape position, subaqueous soil mapping uses bathymetric maps to identify landscapes and landforms (a glossary of subaqueous landforms is available at: [ Glossary of Subaqueous Soil Landscape Terms] ). Shovels are replaced with augers and special tools, such as peat corers and vibracore, to obtain the soil samples.

Uses of Subaqueous Soil Mapping:

A major use of traditional soils surveys is to provide interpretation for various land uses and environmental planning. Interpretations for subaqueous soils are currently being developed for a variety of uses. As more areas are surveyed and more data collected a wide array of soil interpretations are expected.


* Demas, G. P. 1993. Submerged soils: a new frontier in soil survey. Soil Survey Horizons 34: 44-46.
* Demas, G. P., M. C. Rabenhorst, and J. C. Stevenson. 1996. Subaqueous Soils: A pedological approach to the study of shallow water habitats. Estuaries 19: 229-237.

* Demas, G. P., and M. C. Rabenhorst. 1998. Subaqueous soils: a resource inventory protocol. Proceedings of the 16th World Congress on Soil Science, Montpellier, France. August 20-26,1998. Sym #17, on CD.

* Demas, G. P., and M. C. Rabenhorst. 1999. Subaqueous soils: pedogenesis in a submersed environment. Soil Sci. Soc. Am J. 63: 1250-1257.

* Demas, G. P., and M. C. Rabenhorst. 2001. Factors of Subaqueous Soil Formation: a System of Quantitative Pedology for Submersed Environments. Geoderma. 102:189-204

* Bradley, Michael P. and Stolt, Mark H. [ Subaqueous soil-landscape relationships in a Rhode Island estuary Soil Science Society of America Journal (Internet) (October 2003), 67(5):1487-1495]

External Subaqueous Soil Links

[ Subaqueous Soil Information Page from]

[ The Mapping Partnership for Coastal Soils and Sediment (Rhode Island)]

[ Proposed Amendments to Soil Taxonomy to Accommodate Subaqueous Soils]

[ Presentations Made at the National Workshop for Subaqueous Soils]

[ Watch a News Segment about Subaqueous Soils]

Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • subaqueous soil —    Soil that forms in sediment found in shallow, permanently flooded environments. Excluded from the definition of these soils are any areas “permanently covered by water too deep (typically greater than 2.5 m) for the growth of rooted plants.”… …   Glossary of landform and geologic terms

  • submerged-upland soil —    Mineral or organic soil that primarily formed in a subaerial setting but is now under water, commonly in intertidal or subaqueous settings. Inundation could occur for various reasons (e.g., sea level rise in a marine or estuarine system or… …   Glossary of landform and geologic terms

  • Martian soil — is the fine regolith found on the surface of Mars. Its properties can differ significantly from those of terrestrial soil. The term Martian soil typically refers to the finer fraction of regolith, that which is composed of grains one centimeter… …   Wikipedia

  • George Demas — Infobox Scientist name = George P. Demas caption = George P. Demas in the field. birth date = birth date|1958|4|28|df=y death date = death date and age|1999|12|23|1958|4|28|df=y death place = Snow Hill, Maryland residence = U.S. nationality =… …   Wikipedia

  • New Jersey v. Delaware — Supreme Court of the United States Argued November 27, 2007 Decided March 31 …   Wikipedia

  • tunnels and underground excavations — ▪ engineering Introduction        Great tunnels of the world Great tunnels of the worldhorizontal underground passageway produced by excavation or occasionally by nature s action in dissolving a soluble rock, such as limestone. A vertical opening …   Universalium

  • river — river1 riverless, adj. riverlike, adj. /riv euhr/, n. 1. a natural stream of water of fairly large size flowing in a definite course or channel or series of diverging and converging channels. 2. a similar stream of something other than water: a… …   Universalium

  • continental landform — ▪ geology Introduction       any conspicuous topographic feature on the largest land areas of the Earth. Familiar examples are mountains (including volcanic (volcanism) cones), plateaus, and valleys. (The term landform also can be applied to… …   Universalium

  • Sundarbans — Infobox World Heritage Site WHS = The Sundarbans State Party = West Bengal (India),Bangladesh Type = Natural Criteria = ix, x ID = 798 Region = Asia Pacific Year = 1997 Session = 21st Link = Sundarbans ( bn.… …   Wikipedia

  • Vargas tragedy — A part of Vargas state after the 1999 mudslides Date December 14, 1999 (1999 12 14) December 16, 1999 (1999 12 16) Location …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”