Accession Number : ADA322676

Title :   Wigeongrass (Ruppia maritima): A Literature Review.

Descriptive Note : Research paper no. 10,

Corporate Author : FISH AND WILDLIFE SERVICE JAMESTOWN ND NORTHERN PRAIRIE WILDLIFE RESEARCH CEN TER

Personal Author(s) : Kantrud, Harold A.

PDF Url : ADA322676

Report Date : 1991

Pagination or Media Count : 63

Abstract : Wigeongrass (Ruppia maritima L.) is a submersed macrophyte of nearly cosmopolitan distribution and worldwide importance as a waterfowl food. Unfortunately, the plant no longer inhabits vast areas disturbed by human activities. Taxonomic status of the plant is uncertain, especially in North America. In mild climates, in habitats subject to environmental extremes, the plant behaves as an annual (vegetation perishes), or as a perennial in deeper, more stable habitats (some vegetative parts grow year round). Drupelets (seeds) provide a mechanism for wigeongrass to survive periods of drought and excessive water salinity. These sexual propagules can be washed ashore or carried by birds or fish for long distances. Wigeongrass mostly occurs in temporarily to permanently flooded mesohaline-hyperhaline estuarine wetlands, but it also occurs inland in fresh to hypersaline palustrine and lacustrine wetlands. Most populations inhabit warm, relatively unpolluted, and well lit waters <2.0 m deep where fetches and wave action are not great. The species is probably best adapted to stable water levels but can tolerate significant water level fluctuations, including periodic exposure in tidal areas. Robust growth occurs in areas of slow current. Wigeongrass is alone among the submersed North American angiosperms in tolerance to high salinity, but it is likely at a competitive disadvantage among specialist taxa in soft or acidic waters. The species grows in nearly all common bottom substrates, but growth is favored by aerobic and low H2S conditions. Turbidity frequently limits wigeongrass growth in waters overlying easily suspendible bottom substrates. Wigeongrass often occurs in monotypic stands, yet grows with many other submersed and emergent macrophytes.

Descriptors :   *ENVIRONMENTAL PROTECTION, *VEGETATION, *HABITATS, *FOOD, *PLANTS(BOTANY), *WATERFOWL, TEMPERATURE, WATER WAVES, LITERATURE SURVEYS, HUMANS, POPULATION, CYCLES, SEASONAL VARIATIONS, TOLERANCE, CLIMATE, LEVEL(QUANTITY), EXPOSURE(PHYSIOLOGY), RANGE(EXTREMES), WETLANDS, SALINITY, BIRDS, BOTTOM, TAXONOMY, DROUGHT, NORTH AMERICA, ACIDS, SEEDS.

Subject Categories : Biology
      Ecology
      Environmental Health and Safety

Distribution Statement : APPROVED FOR PUBLIC RELEASE