Invertebrate communities

Benthic invertebrate communities are taxonomically and trophically complex, and their abundance and species composition in a water body often vary seasonally and among years. Sediment-dwelling invertebrates can be readily sampled but considerable effort is often required to remove benthic organisms from grab samples of sediment, to determine their taxonomic composition, and to obtain sufficient sample mass of a target taxon for analysis. Sampling would not substantially affect target populations. 

Jackson DA, Harvey HH. 1993. Fish and benthic invertebrates community concordance and community-environment relationships. Can J Fish Aquat Sci 50 2641-2651. 

Damasio J, Tauler R, Teixido E, Rieradevall M, Prat N, Riva MC, Soares AMVM, Barata C (2008) Combined use of Daphnia magna in situ bioassays, biomarkers and biological indices to diagnose and identify environmental pressures on invertebrate communities in two Mediterranean urbanized and industrialized rivers (NE Spain). Aquat Toxicol 87 (4) 310-320... 

Lods-Crozet B, Castella E, Cambin D, Ilg C, Knispel S, Mayor-Simeant H (2001) Macro-invertebrate community stmcture in relation to environmental variables in a Swiss glacial stream. Freshw Biol 46 1641... 

In addition, Fairchild et al. (64) exposed an outdoor stream community consisting of a diverse invertebrate benthic population, Hyallela azteca, and Pimephales promelas. These organisms were exposed to a mean concentration of 0.35 mg/L, a concentration not expected to cause adverse effects if the laboratory-generated NOEC data were protective of the system. End points assessed during the 45-day exposure included a variety of periphytic and benthic invertebrate community measurements. These authors found no effects on the biota contained in this study at 35 mg/L of C12LAS. 

Small mammals are also favored by conservation tillage. In Illinois, no-till corn fields had more abundant and more diverse populations of invertebrates, birds, and small mammals than conventionally tilled corn (Warburton and Klimstra, 1984). A greater diversity and proportionately more predators were noted within the invertebrate community in no-till fields. Small mammal populations also were more stable in no-till. 

Canfield, T.J., Brunson, E.L., Dwyer, F.J., Ingersoll, C.G. and Kemble, N.E. (1998) Assessing sediments from Upper Mississippi River navigational pools using a benthic invertebrate community evaluation and the sediment quality triad approach, Archives of Environmental Contamination and Toxicology 35 (2), 202-212. 

Step 3. On the plume map, match the lowest IC25 for each test conducted with the same concentration of the effluent plume to estimate the extent of the effects zone. Step 3. Assign an LTF rating of 1 to 5 to the benthic invertebrate community survey based on the percentage of effluent-related effects compared to the total number of descriptors measured. 

Rating the relationship between ZPE andfield measurements The relationship between sublethal toxicity tests and field measurements can be rated on the basis of zones of potential effect (Environment Canada, 1999). The following points describe the criteria used for rating the relationship between zones of potential effect for each sublethal test (lowest IC25) and potential effluent-related effects on fish or the benthic invertebrate community (Moody, 1992). 

Step 3 assign a rating of 1 to 5 to the invertebrate community survey (ICS) based on the percentage of potential effluent-related effects (Tables 4 and 5) relative to endpoints measured. 

Levels of total organic carbon (TOC) followed a gradient pattern, and ranged from 4.9% at the near-field to 0.7% in the far-far field (mean 3.1%), primarily due to historical fibre deposits. Oil contamination was present in the near-field and far-field sediments. Triplicate samples were collected using a standard Ponar grab and pooled. Invertebrates were preserved until they were counted and identified. Statistically significant differences between reference and exposure areas were observed for three of the five invertebrate community indices calculated (Tab. 8). 

Table 8. Significant differences of benthic invertebrate communities and selected benthic taxa between sites for Kimberly-Clark.

Rating ecosystem indicators - benthic invertebrate community... 

Using the ZPE scheme, the study of effluent discharge situations at 16 Ontario pulp and paper mills demonstrated a majority of strong or moderately strong relationships between sublethal toxicity tests and ecosystem indicators (fish populations and benthic invertebrate communities). The locations of effects in benthic organisms corresponded in 100% of cases with zones predicted by the Ceriodaphnia test and in 81% of cases with predictions from the Selenastrum test. The fathead minnow test did not perform as well, predicting effects on fish in only 53% of cases (Moody, 2000). 

In the second publication (Bombardier and Blaise, 2000), laboratory toxicity data derived from two larger projects conducted on freshwater sediments were integrated in the SED-TOX index and it was field validated using four benthic community metrics (species richness, number of taxa in the orders Ephemeroptera, Plecoptera, and Trichoptera, the Shannon-Wiener diversity index, and the ICI-SL which is a version of the Invertebrate Community Index modified for the St. Lawrence River). 

Figure 2. Relationship between SED-TOX scores and benthic community metrics. Scores for each metric are classified as follows A) Richness < 17 = degraded, 17-23 = moderately degraded, 24-32 = fairly clean, > 33 = clean (taken from Willsie, 1993a, b) B) H < 1 = degraded, 1-3 = moderately degraded > 3 = clean (Wilhm, 1967) C) EPT < 6 = degraded, 7-13 = fairly clean (taken from U.S. EPA, 1996a) D) 0 16 = clean (adapted from Willsie, 1993a, b). EPT taxa richness in the orders Ephemeroptera, Plecoptera and Trichoptera ICI-SL Invertebrate community Index for the St. Lawrence River.

Willsie, A. (1993a) Adaptation of the invertebrate community index (ICI) to the St. Lawrence River, in E.G. Baddaloo, S. Ramamoorthy, and J.W. Moore (eds.), Proc. 19lh Annual Aquatic Toxicity Workshop, Edmonton, 4-5 October 1992. 

ICI-SL Invertebrate Community Index modified for the St. Lawrence River... 

Maintenance of soft-bottom benthic invertebrate communities capable of supporting local fish populations. COPC concentrations in sediment will not result in toxicity to the soft-bottom benthic community. Assess the effect of COPCs in sediment on the survival of two amphipod species (Eohaustorius estuarius and Rhepoxynius abronius). Assess the effect of COPCs in sediment on survival and growth of the polychaete, Neanthes arenaceodentata. Assess in situ changes in benthic community structure (diversity and abundance). 

The capacity of chemoautotrophic bacteria to oxidize hydrogen sulfide as a source of energy for CO2 fixation is well known (20). However, the realization that entire bacterial and invertebrate communities can be fueled by... 

Kreutzweiser DP, Capell SS, Sousa BC. 1995. Hexazinone effects on stream periphyton and invertebrate communities. Environ Toxicol Chem 14 1521-1527. 

Liess M, von der Ohe PC. 2005. Analyzing effects of pesticides on invertebrate communities in streams. Environ Toxicol Chem 24 954-965. 

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