Sago Pondweed (Potamogeton pectinatus L.):
A Literature Review
Habitat
Habitat--Wetland type
Sago normally occurs in water bodies or those portions where water is permanently present (Mirashi 1954; Verhoeven 1980a; Grillas and Duncan 1986) or absent for no more than 1 to 3 months (Coetzer 1987.) Stream environments favor linear-leaved species like sago that tend to grow from the base (Madsen 1986), but Pip (1987) found no significant tendencies for sago to occur more frequently in either lentic or lotic habitats. Sago occurs in the estuarine, riverine, lacustrine, and palustrine wetland systems of Cowardin et al. (1979). Under this classification scheme, sago is a dominance type in the class Aquatic Bed in wetlands with subtidal and irregularly exposed water regimes in estuarine systems; in tidally-influenced riverine systems, sago occupies permanently flooded and intermittently exposed sites. In inland systems, sago variously grows in wetlands with permanently flooded, intermittently exposed, semipermanently flooded, or artificially flooded water regimes.In a wetland classification system developed specifically for basins in the glaciated prairie region of North America (Stewart and Kantrud 1971), sago is restricted to the deep marsh zone of permanent and semipermanent ponds and lakes. Sago occasionally occurs in seasonal (Stewart and Kantrud 1971) wetlands if surface water is continuously present for more than 3 years, and the presence of sago in these wetlands suggests that they have experienced, or can be expected to experience, several years of continuous flooding (Miller 1973). Sago became well established when formerly dry sites in Utah were continuously flooded to a depth of 30 cm for 2 years (Nelson 1954). Sago reaches peak frequency in the regenerating and degenerating phases of prairie wetlands defined by Van der Valk and Davis (1978). The former phase occurs just after basins refill; the latter, just before a variety of agents causes a rapid decline in emergent hydrophytes.
Previous Section -- Decomposition
Return to Contents
Next Section -- Habitat--Wetland area and fetch
