Peats water relations

CDAA, molinate, EPTC, vernolate, pebulate, CDEC, and cycloate are all relatively mobile in soil systems (123, 385, 386, 387, 388 389, 390, 391). The herbicides leached more readily in coarse textured soils than in fine textured ones and did not significantly leach in peat or muck soils (386, 387, 388, 391), Leachability of the compounds was related to their water solubilities (compounds of higher solubilities moved more than less soluble ones) and to the organic matter and clay contents of the soils (less movement as the organic matter and clay content increased). 

Peat soils are considered as cold soils because the surface portion and the air above usually have a lower temperature than mineral soils in the same locality. Peat soils hold much water and are located at the lowest elevations, and of course cold air accumulates in depressions. In addition, peat is a much poorer conductor of heat than mineral soils, and hence the transfer of heat upward from the subsoil is slow. Heat moves fairly rapidly in moist peat, or in mucks, but dry loose peat acts as an insulation. These temperature relations are of great importance in regions such as Florida, where vegetables and fruits are being grown for the winter and early spring markets. 

The Duluth-Superior Harbor (St. Louis River) contains HS from upstream peat bogs, which explains its tea-colored waters. The pH of its waters is also in the neutral range. Figure 32.12 (Stevenson, 1982) illustrates the range of colors associated with HS and how these colors are related to molecular weight, carbon content, oxygen content, acidity, and solubility. 

Breakdown of organic matter in an oxidising environment does not lead to the preservation of fossil fuels. In the terrestrial environment, anoxic conditions and increasing temperature lead to the transformation of woody plant materials, cellulose to lignins releasing humic acids and methane. Humic and the related fulvic acids are found in soils, coals and peats, as well as various water bodies throughout the environment. 

---