Littoral zone

From the large body of literature about chemical defense in the benthic environment (benthos the bottom of the sea and the littoral zones), only a few aspects can be highlighted here. The selection of examples from the benthos will focus on dynamic defense reactions including fast wound-activated and... 

Wanga H, Wanga W, Yina C, Wang Y, Lua J (2006) Littoral zones as the hotspots of nitrous oxide (N O) emission in a hyper-eutrophic lake in China. Atmos Environ 40 5522-5527 Wendland M, Offenberger K (2007) N-Diingung zu Mais, Bayerisches Landwirtschaftliches Wochenblatt, Ed. 14, p 6... 

Fig. 13.2 Typical vertical zonation pattern of macroalgae in the littoral zones of rocky shores, and the penetration depths of solar radiation expressed as percentage of the incident surface radiation (adapted from Liming 1985)...

Analyses of carbon isotopic composition were performed as an independent measure of potential food sources for zooplankton. The 813C values of terrestrial detritus and of littoral zone emergents such as Carex ranged from -26.0 to -29.2%o (Table I 49, 92). By comparison, the zooplankton were quite depleted in 13C their 813C values were more similar to phytoplankton and ranged from -32.1%o in Daphnia to -41.0%o in Cyclops (Table I). 

The tube method involved insertion of precleaned acrylic tubes (5-cm diameter) into the littoral zone sediments at a lake-water depth of about 1 m (about 15 cm into sediments). Lake water within the tube was removed by using a peristaltic pump and Teflon line. Once the tube was purged of lake water, groundwater was allowed to fill it to a depth of about 25 cm. The tube was then purged three times with groundwater before obtaining the sample. 

Figure 4. Mercury concentrations in littoral zone pore waters in Pallette Lake...

At whole lake scales, littoral zones are a major component of autochthonous DOM production and important sources of labile organic matter for aquatic bacteria. Of the approximately one billion lakes in the world, the littoral zone accounts for more than 95% of lake surface area in nearly 99.8% of all lakes (Wetzel, 1983 Fig. 3a). The importance of shallow waters is even more marked when the bounds of lakes are expanded to include wetlands. With such an expanded view, the littoral zone and wetlands comprise more than 95% of the area in 99.999% of all lakes (Fig. 3a). Clearly, shallow waters are a dominant feature of lentic ecosystems. 

FIGURE 3 Proportion of lake area accounted for by littoral zones for the world s lakes (a), and the proportion of extracellular (ER) dissolved organic matter inputs derived from littoral zones (b see text for description of the model). The solid lines illustrate relationships in which lake boundaries are restricted to littoral and pelagic zones and the dotted lines illustrate patterns in which lake boundaries are expanded to include adjacent wetlands. In (b), the two sets of lines illustrate the range in the contribution of littoral zones to total lake ER with variation in rates of primary production for phytoplankton (0.1-2.0 kg organic matter m-2 yr 1) and macrophytes (0.6-3.8 kg organic matter nT2 yr 1). The relationship between littoral zone area and number of lakes is from Wetzel (1983). 

St. Louis VL. 1993. Element concentrations in chironomids and their abundance in the littoral zone of acidified lakes in Northwestern Ontario. Can J Fish Aquat Sci 50 953-963. 

Herbivores in the sea are phylogenetically more diverse than on land. Seaweeds are eaten by diverse vertebrate ectotherms and an array of invertebrate consumers that vary both in their selectivity and in their impact on algae. Vertebrate herbivores are comprised of various fish families and species, as well as some turtles.24 111 120 125 Invertebrate herbivores span at least four different phyla and include an array of gastropods (such as snails, limpets, sacoglossans, sea hares, cephalaspideans, and chitons), urchins, crabs, amphipods, isopods, shrimps, polychaete worms, copepods, and a few insect species that feed on algae living in the upper littoral zone.24 110 123 126-135... 

Williams et al. (2002) compared the plant and macroinvertebrate communities of small microcosms to those of natural ponds in Britain. Using multivariate analyses, they showed that the fauna of the microcosms were most similar to those of less common deep circumneutral ponds and did not closely mimic more commonly occurring shallow ponds. The microcosms lacked a wide variety of invertebrate groups and plants typical of shallow natural ponds that possess a littoral zone. 

Littoral transport the movement of littoral drift in the littoral zone by waves and currents including movement parallel (longshore transport) and perpendicular (on/offshore transport) to the shore. 

Buzzelli, C.P. (1998) Simulation modeling of littoral zone habitats in lower Chesapeake Bay. I. An ecosystem characterization related to model development. Estuaries 21, 659-672. 

During the recent years, in the waters off Romania, centracant Centracan-thus cirrus, which probably also penetrated from the Mediterranean Sea, was observed. To date, it has significantly increased its abundance and now represents a commercial fish in the littoral zone of Romania. In the central part of the sea, its developing eggs were first found in June 1982 [70]. 

Larmola, T., Aim, J., Juutinen, S., Martikainen, P. J. Silvola, J. (2003). Ecosystem CO2 exchange and plant biomass in the littoral zone of a boreal eutrophic lake. 

Atlas R. M., Boehm P. D., and Calder J. A. (1981) Chemical and biological weathering of oil from the Amoco Cadiz spillage within the littoral zone. Estuar. Coast. Shelf Sci. 12, 589-608. 

Caldwell, D.E., Caldwell, S.J. and Tiedje, J.M., 1975. An ecological study of the sulfur-oxidizing bacteria from the littoral zone of a Michigan lake and a sulfur spring in Florida. Plant Soil, 43 101—114. 

Laternula elliptica, one of the largest bivalves in the Antarctic marine environment, has been proposed as a biomonitor of trace metals in coastal waters (67, 70). Although gastropod molluscs have been less extensively used for monitoring trace metals pollution that mollusc bivalves, they show eharacteristics useful for these studies (61). The limpet Nacella concinna is the most abundant and often the only invertebrate found in the littoral zone of the Antarctic peninsula. 

In the littoral zone, temperatures can range to extremes. Some organisms have specialized adaptations that help moderate fluctuations in temperature. Many animals, for example, live in light-colored shells that reflect heat rather than absorb it. Others have sculptured shells with extensions that help dissipate heat. 

Besides dryness and extreme temperatures, littoral zone residents are exposed to a variety of salinities. In shallow... 

Diatoms living in the surf of the littoral zone are constantly on the move, migrating back and forth with the water. Offshore, they travel on air bubbles from the bottom of the shallow water to its surface. As a wave rolls to shore, diatoms ride it in and wash up on the beach. Here they secrete sticky mucus that helps them sink just below the sand s surface. As a wave rushes back to ocean, the diatoms wash out with it, back to their offshore position. From here, they float to the surface and reenter on another wave. 

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