wetlandsmarshes

Wetlands are ecosystems saturated with water, either permanently or seasonally, creating soils with low oxygen content and specialized vegetation. Marshes are a type of wetland dominated by herbaceous plants such as grasses, reeds, and sedges, with little or no woody growth. They occur worldwide in coastal and inland areas and may be freshwater or saline.

Hydrology and soils: Prolonged inundation leads to hydric soils and anaerobic conditions. Water levels may fluctuate seasonally or be influenced by tides in coastal marshes. In some regions, peat can accumulate in marshes, contributing to carbon storage.

Vegetation and wildlife: Marshes support a variety of adaptive plants like cattails (Typha), bulrushes (Scirpus), and Spartina in coastal zones. They host birds, fish, amphibians, invertebrates, and mammals that rely on emergent vegetation and shallow water for food and shelter.

Functions and benefits: Marshes reduce flood peaks, trap sediments, filter pollutants, support groundwater recharge, and store carbon. They also serve as important nursery habitats and maintain water quality, contributing to biodiversity and cultural values.

Types and distinctions: Coastal marshes include salt and brackish tidal marshes, while inland freshwater marshes occur in river basins and depressions. Marshes differ from swamps by the dominance of herbaceous rather than woody plants.

Threats and conservation: Marshes face drainage, conversion to agriculture or development, pollution, invasive species, and climate-change impacts such as sea-level rise. Conservation approaches include protection of existing marshes, restoration of hydrology and native vegetation, invasive species control, and careful land-use management.