Ecosystems benthic

Artigas J, Romani AM, Gaudes A, et al (2009) Benthic structure and metabolism in a Mediterranean stream from biological communities to the whole stream ecosystem function. Fresh. Biol. 54 DOI 10.1111/j.l365-2427.2008.02140.x... 

When selecting a receptor in aquatic ecosystems, this may be the aquatic organisms, the benthic organisms or the fauna (birds and mammals) or human beings that consume fish (Figure 6). 

Duffy JE (2002) Biodiversity and ecosystem function the consumer connection. Oikos 99 201-219 Duffy JE, Hay ME (2000) Strong impacts of grazing amphipods on the organization of a benthic community. Ecol Monogr 70 237-263... 

Literature about bioaccumulation of different surfactant groups is limited, specially for benthic organisms. The bioavailability of sediment sorbed surfactants represents one of the key questions for evaluating their toxicity and impact on ecosystems. 

Injection of compressed CO2 into the deep ocean has already been tested. The goal of this approach is to emplace the CO2 into waters with low temperatures, ensuring the formation of relatively immobile gas hydrates. This strategy has the potential to sequester thousands of gigatonnes of carbon, but likely environmental impacts include (1) a change in the pH in the seawater near the emplaced gas hydrates, (2) benthic kills, (3) other ecosystem impacts, and (4) release back to the atmosphere as an eventual consequence of meridional overturning circulation. 

O2 levels of the waters feeding this upwelling area are likely to contribute to an expansion in the intensity and vertical extent of its hypoxic zone. An important consequence would be a loss of oxygenated habitat in the underlying shelf and slope ecosystems resulting in a widespread mortality of benthic species. 

Effects assessment, by, as in the case of risk assessment for chemicals and pesticides, determining a set of marker organisms (including algae, zebrafish, insect larvae, benthic worm, water flea, etc.) that represent ecosystem components and food networks and are used to indicate acute and chronic effects. This step is also used to define the predicted no-effect concentrations (PNECs). 

Both of the models presented here are based on the flow of nitrogen through ecosystems in one case a nearshore kelp-bed system and in the other a general offshore plankton community. The klep bed model was developed to explore the hypothesis that nitrogen flow is affected by horizontal water transport in shallow water marine systems here wave action or mixing associated with horizontal transport are likely to retain nitrogen in the photic zone and the benthic community is of fixed location so that boundaries of the system can be easily defined. In pelagic systems, on the other hand, the community tends to move horizontally with water in the mixed layer, and vertical transport into and out of the mixed layer is an important feature of the system dynamics. 

Hunt, C.D., 1983. Variability in the benthic Mn flux in coastal marine ecosystems resulting from temperature and primary production. Limnol. Oceanogr., 28(5) 913-923. 

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