Fauna, benthic

Figure 7. Excess activity versus depth (left) and X-radiograph (right) in a sediment core collected from the New York Bight, showing the importance of mixing by benthic fauna in the upper part of the seabed. Abundant individnals of the small bivalve Nucula proximo may be seen in the X-radiograph near the sediment-water interface, and the light-colored areas represent bnrrows of Nephtys sp. and Ceriantheopsis sp. Reprinted from Estuarine Coastal and Shelf Science (formerly Estuarine and Coastal Marine Science) Vol. 9, Cochran and Aller, pp. 739-747, 1979, with permission from Elsevier Science.

Tributyltin antifouling paints were banned for use in tin-based paints in the U.K. in 1987. Field work on the River Crouch Estuary showed that sediments from areas most contaminated with TBT in 1987 contained 0.16 mg TBT/kg DW however, by 1992 this had declined to 0.02 mg TBT/kg DW. TBT declines were accompanied by increases in abundance and diversity of benthic fauna, especially bivalve molluscs and amphipod crustaceans (Rees et al. 1999 Waldock et al. 1999). 

Schiitz C, Wallinger M, Burger R, Fureder L (2001) Effects of snow cover on the benthic fauna in a glacier-fed stream. Freshw Biol 46 1691... 

Burgherr P, Ward JV (2001) Longitudinal and seasonal distribution patterns of the benthic fauna of an alpine glacial stream (Val Roseg, Swiss Alps). Freshw Biol 46 1705... 

Knispel S, Castella E (2003) Disruption of a longitudinal pattern in environmental factors and benthic fauna by a glacial tributary. Freshw Biol 48 604... 

Schiitz (1999) The benthic fauna of high Alpine streams. Dissertation, Institut fur Zoologie und Limnologie, Universitat Innsbruck, Innsbruck, Austria... 

Blanchard, A. and Feder, H.M. (2003). Adjustment of benthic fauna following sediment disposal at a site with multiple stressors in Port Valdez, Alaska. Mar. Pollut. Bull., 46 1590-1599. 

Although basic information on the spatial and temporal distribution of benthic bacterial biomass and activity is available, a number of questions still remain open. Among these, the measurement of bacterial production, seasonal variations in the metabolic activity of bacterial populations, and interactions between bacteria and the benthic fauna need further attention. 

Balthis, W.L., Hyland, J.L., Scott, G.I., Fulton, M.H., Bearden, D.W. and Greene, M.D. (2002) Sediment quality of the Neuse River estuary, North Carolina an integrated assessment of sediment contamination, toxicity, and condition of benthic fauna, Journal of Aquatic Ecosystem Stress and Recovery 9, 213-225. 

Wilcock, R.J., Smith, T.J., Pridmore, R.D., Thrush, S.F., Cummings, V.J., Hewitt, J.E. (1993) Bioaccumulation and elimination of chlordane by selected intertidal benthic fauna. Environ. Toxicol. Chem. 12, 733-742. 

Kristensen, E. (1988) Benthic fauna and biogeochemical processes in marine sediments microbial activities fluxes. In Nitrogen Cycling in Coastal Marine Environments. SCOPE (Blackburn, T.H., and Sprensen, J., eds.), pp. 275-299, Scope, Chichester, UK. 

Rosenberg, R., Nilsson, H.C., and Diaz, R.J. (2001) Response of benthic fauna and changing sediment redox profiles over a hypoxic gradient. Estuar. Coastal Shelf Sci. 

Marine sponges are conspicuous sessile members of the benthic fauna, and often brightly colored or soft bodied. Field observations suggest that they are avoided by fishes, crabs, and other generalist predators, although certain groups of mollusks, in particular the nudibranchs, are specialized sponge eaters. There is a considerable... 

Aller, J. Y., and R. C. Aller. 1986. "General characteristics of benthic faunas on the Amazon inner continental shelf with comparison to the shelf off the Changjiang River, East China Sea." Continental Shelf Research 6 291-310. 

In addition to the microbial community present in aU sediments other organisms can substantially alter the nature of N release from sediment, particularly macroalgae, microphytobenthos, and benthic fauna. 

Following Emiliani s (1955) discovery, other laboratories established the capability to apply oxygen isotope variations to oceanic temperature history. It is worth a brief mention of two further major advances relevant to Urey s original conception. In 1967, Nicholas Shackleton of Cambridge University reported the first systematic down-core variations in benthic foraminifera (Shackleton, 1967). He argued that benthic fauna, because they lived in the near-freezing bottomwaters of the ocean, would mainly record... 

These diagenetic models have proven effective in understanding the effects of various sedimentary processes on silica dynamics in the seabed (Johnson, 1976 Ragueneau et al., 2000). For example, the effect of bioturbation by benthic fauna on pore-water silicate profiles has been examined (Schinck and Guinasso, 1978). Higher intensities of bioturbation lead to higher asymptotic silicate values at depth because the benthic fauna are mixing down particles from the surface... 

Reichardt W. (1988) Impact of the Antarctic benthic fauna on the enrichment of biopolymer degrading pshychrotrophic bacteria. Microb. Ecol. 15, 311—321. 

Shallow marine environments include coral and algal reefs as well as other bioherms and many favour calcification by benthic fauna. Stromatolites and stromatolitic environments are also typical shallow marine formations. The shallow marine carbonate environment may be subdivided into more or less agitated waters with dominantly benthic fauna, calm shallow areas with carbonate muds (e.g. Bahama Banks) with ooids as typical forms of deposits and reef areas with their complicated patterns of calcification and deposition (Bathurst, 1975 Kinsey and Davies, Chapter 2.5). 

The carbon-14 age of calcite-rich deep sea sediments as a function of depth in the sediments at different locations in the ocean. Expedition names and core numbers are indicated along with the core location and water depth. Data (circles) indicate a 5—10 cm C mixed layer in the surface sediments everywhere in the deep ocean due to bioturbation by benthic fauna. The figure in the upper left illustrates the idealized relation between profile slope and sedimentation rate. Redrawn from Peng and Broecker (1984). 

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