ntrast to land ecosystems, dead materials and excreta in aquatic ecosystems are typically transported by water flow; finer particles tend to be transported farther or suspended longer. In freshwater bodies organic material from plants can form a silt known as mulm or humus on the bottom. This material, some called undissolved organic carbon breaks down into dissolved organic carbon and can bond to heavy metal ions via chelation. It can also break down into colored dissolved organic matter such as tannin, a specific form of tannic acid. In saltwater bodies, organic material breaks down and forms a marine snow that slowly settles down to the ocean bottom. Terrestrial ecosystems Detritus occurs in a variety of terrestrial habitats including forest, chaparral and grassland. In forests the detritus is typically dominated by leaf, twig, and bacteria litter as measured by biomass dominance. This plant litter provides important cover for seedling pr
otection as well as cover for a variety of arthropods, reptiles and amphibians. Some insect larvae feed on the detritus. Fungi and bacteria continue the decomposition process after grazers have consumed larger elements of the organic materials, and animal trampling has assisted in mechanically breaking down organic matter. At the later stages of decomposition, mesophilic micro-organisms decompose residual detritus, generating heat from exothermic processes; such heat generation is associated with the well known phenomenon of the elevated temp
