Lakes benthic invertebrates

Wong, A.H.K., D.J. McQueen, D.D. Williams, and E. Demers. 1997. Transfer of mercury from benthic invertebrates to fishes in lakes with contrasting fish community structures. Canad. Jour. Fish. Aquat. Sci. 54 1320-1330. 

Significant concentrations of cyanotoxins have been found to accumulate in the tissues of macroinvertebrates such as mollusks and crustaceans, presenting an indirect route of exposure for invertebrates, fish, and aquatic mammals at higher trophic levels (Negri and Jones 1995). In natural systems, mortality among benthic invertebrate herbivores is probably low because most bloom-forming bacteria are planktonic and only periodically come into contact with the benthos. Nevertheless, Kotak et al. (1996) determined that enhanced mortality of snails at the end of a bloom cycle in Canadian lakes was due to consumption of Microcystis cells that had formed a scum on the surface of macrophytes. Oberemm et al. (1999) found that aqueous microcystins, saxitoxins, and anatoxin-a all resulted in developmental delays in fish and salamander embryos. Interestingly, more severe malformations and enhanced mortality were observed when larvae were exposed to crude cyanobacterial extracts than to pure toxins applied at natural concentrations (Oberemm et al. 1999). 

Decomposition rates of some organic substrates are reduced. Substantial changes in the species composition of primary producers occur. The richness of phytoplankton species is reduced, while biomass and productivity of phytoplankton are not reduced by acidification. The biomass of herbivorous and predaceous zooplankton is probably reduced because of reductions in numbers of organisms and/or reduction in their average size. Many benthic invertebrates such as species of snails, clams, crayfish, amphipods, and various aquatic insects are intolerant of low pH and are seldom found in acidic lakes. However, certain large aquatic insects such as water boatmen and gyrinids are very acid tolerant and may become the top predators in some acidified lakes. Acidification of aquatic systems has major effects on fish population. 

In alpine regions, especially in maritime climates, snow depths may be considerable. This insulates the stream environment from subzero temperatures. River ice is an important environmental component of alpine rivers and has resulted in adaptive mechanisms among the fauna [50, 51]. Despite these adaptations, winter conditions inevitably cause high mortality to stream invertebrates and fish, especially in reaches with unstable snow and ice cover and thereby susceptible to formation of frazil and anchor ice. The lack of winter ice cover in lake outflows and groundwater-fed reaches provides a favourable environment for primary producers and those benthic invertebrates utilising primary production [52]. 

Poulton DJ, Simpson KJ, Barton DR, et al. 1988. Trace metals and benthic invertebrates in sediments of nearshore Lake Ontario and Hamilton Harbor. J Great Lakes Res 14 52-65. 

Landrum et al. (1992) developed a kinetic bioaccumulation model for PAHs in the amphipod Diporeia, employing first-order kinetic rate constants for uptake of dissolved chemical from the overlying water, uptake by ingestion of sediment, and elimination of chemical via the gills and feces. In this model, diet is restricted to sediment, and chemical metabolism is considered negligable. The model and its parameters, as Table 9.3 summarizes, treat steady-state and time-variable conditions. Empirically derived regression equations (Landrum and Poore, 1988 and Landrum, 1989) are used to estimate the uptake and elimination rate constants. A field study in Lake Michigan revealed substantial differences between predicted and observed concentrations of PAHs in the amphipod Diporeia. Until more robust kinetic rate constant data are available for a variety of benthic invertebrates and chemicals, this model is unlikely to provide accurate estimates of chemical concentrations in benthic invertebrates under field conditions. 

This model is similar to that of Morrison et al. (1996), the main difference being in the parameterization. The fugadty model provided satisfactory predictions of polychlorinated biphenyl concentrations in Diporeia and oligochaetes colleded in Lake Ontario. The model is a potentially useful tool for quantifying chemical exposure routes to benthic invertebrates and prediding chemical concentrations in their tissues based on chemical concentrations in water, sediment and diet. 

Canfield, T.J., Dwyer, F.J., Fairchild, J.F., Haverland, P.S., Ingersoll, C.G., Kemble, N.E., Mount, D.R., La Point, T.W., Burton, G.A., and Swift, M.C. (1996) Assessing contamination in Great Lakes sediments using benthic invertebrate communities and the sediment quality triad approach, Journal of Great Lakes Research 22, 565-583. 

The most obvious impact of sediment-associated pollutants on aquatic biota is direct acute toxicity and there is considerable literature on both laboratory and field effects of toxic substances on marine and freshwater invertebrates (Baker, 1980 Reynoldson, 1987). For example, Warwick (1980) and Wiederholm (1984) observed deformities in chironomid larvae mouthparts at polluted sites of lakes in Canada and Sweden Milbrink (1983) has shown setal deformities in oligochaetes exposed to high sediment mercury levels. Indirect effects resulting from sediment contamination oftenly include changes in benthic invertebrate community structure. For example, Lock et al. (1981) evidenced increased growth of bacterial flora and algal cells on oiled substrates and a consequent stimulation of macroinvertebrates. Chapman et al. (1982) have shown effects of life history alterations (e.g., impairment of reproduction and age selective toxicity) which have been linked to sediment contaminants. ... 

Traditionally, lake monitoring has focused on physico-chemical parameters (nutrients, oxygen profiles, etc.) and on phytoplankton biomass as indicated by chlorophyll a, on which several classification schemes exist (e.g. OECD, 1982 Cailson, 1977). Only recently, following the new requirement introduced by the WFD to assess lake ecological status (see Cardoso et al., 2006 for a review) have most European countries included several other biological quality elements in their routine monitoring programmes, such as phytoplankton, macrophytes and phytobenthos, benthic invertebrates and fish. 

The indicator (fish, macrophytes, etc.) might not respond to the difference between one lake type and another, i.e. lake depth does not have to change the distribution of benthic invertebrates or perifyton. 

Loss of sensitive species of minnow and dace, such as black-nose dace and fathead minnow in some waters decreased reproductive success of lake trout and walleye, which are important sport fish species in some areas Visual accumulations of filamentous green algae in the littoral zone of many lakes, in some streams Distinct decrease in the species richness and change in species composition of the phytoplankton, zooplankton, and benthic invertebrate communities, although little if any change in total community biomass or production... 

Bruner KA, Fisher SW, Landrum PF (1994) The role of the zebra mussel (Dreissena polymorpha) in contaminant cycling II. Zebra mussel contaminant accumulation from algae and suspended particles, and transfer to the benthic invertebrate Gammarus fasciatus. J Great Lakes Res 20 735-750. 

Table 15 Mean concentrations of perfluorinated compounds ( xg/kg) in invertebrates and benthic algae from the Laurentian Great Lakes (standard error in parentheses) ...

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