Benthic Infauna in the Rhode River
The Rhode River is a representative tributary of the Chesapeake Bay. Macroinvertebrates, such as crustaceans, worms, and mollusks comprise the Rhode River's soft bottom community. They live in or on the bottom of the river in mud, sand, clay, marsh detritus, leaf litter, or combinations of these sediment types. Infaunal species are responsible for significant interactions within the benthic environment which in turn, impact the biodiversity and functional processes within the entire estuarine ecosystem. Long-term data on these species gives us 1) information on the species composition and fluctuating abundances of these organisms over time and in differing habitats and 2) a better understanding of the processes that regulate their community and population dynamics. Such dynamics include predator-prey interactions, recruitment, habitat use and responses to environmental factors such as salinity, temperature, and dissolved oxygen. Integrating benthic infaunal data with our other long-term sampling programs provides insight into processes structuring ecosystem interactions within the Rhode River
As part of a complex food web, infaunal communities are composed of both predators and prey. Trophic level (positions in the food web) of these species may change during its life cycles as the organism grows and their size, feeding mechanism, and nutritional requirements change.
Processes such as bioturbation (sediment disturbance) are caused by infaunal burrowing and feeding, especially by deposit feeder species such as worms or certain species of clams. Bioturbation can, among other things, affect oxygen levels in sediments, cause redistribution and decomposition of organic matter, and alter the amount of suspended particles in the water. This, in turn, may negatively or positively affect water quality, refuge patterns, and feeding behavior of organisms.