Pollution-tolerant species

Grant A. 2002. Pollution-tolerant species and communities intriguing toys or invaluable monitoring tools Human Ecol Risk Assess 8 955-970. 

This family possesses several species very tolerant to pollution. Many species are adapted to very wet sites, typically on the edge of bodies of water, and so are suited for phytoremediation in such environments. In the temperate and cooler zones of Europe, Carex hirta can be recommended Cyperus alternifolius is an alternative for more southerly parts of the continent, and similarly, C. papyrus for the Mediterranean and subtropical zones. All these species can be vegetatively propagated by division of the mother plant. 

Benthic taxa exhibiting significant differences in abundance (at a = 0.05) between reference and exposure areas were noted. If a taxon was considered to be relatively more tolerant of pollution (such as enrichment in pulp mill effluent), it was listed as an Enrichment Indicator Organism . On a scale from 1 to 10, these taxa have pollution tolerances from 6 to 10 (Moody, 2000). If a taxon was considered to be relatively less tolerant of pollution, it was listed as a Toxicity Indicator Organism . These taxa have pollution tolerances from 1 to 5. Species representing both types of indicator groups were found to show potential effluent-related effects at the Kimberly-Clark mill. The total number of potential effluent-related effects is calculated for comparison with the LTF method case study in Section 7.2. 

Measurement of PICT usually involves carrying out short-term (multispecies) toxicity tests on whole communities from clean and contaminated sites. Pollution tolerance is quantified by reduced sensitivity of the toxicant in these tests. The increased tolerance may result from replacement of sensitive species by less sensitive ones, development of heritable tolerance by one or more species, and/or short-term nonheritable acclimation. A significant increase in community tolerance compared to the baseline tolerance at reference sites suggests that the community has been adversely affected by toxicants. In this way, PICT can establish causal linkages between contaminants and effects in monitoring studies (Blanck 2002). 

From the number of different species of fauna (diversity) and an appreciation of their relative sensitivity to pollutants, much can be learned about the condition of fresh or marine waters and sediments [57, 58]. Field experiments to determine the presence or absence of pollution-sensitive species of plants relative to the abundance of tolerant species can also be used [59]. They can also help to determine the bioavailability and acute toxicity of pollutants in bottom sediments. 

The occurrence of fishes in streams is considerably influenced by water pollution. A species which is very resistant against putrefactive pollution is Leuciscus cephalus, in contrast to the majority of salmon-like fish, for example, trout (Salmo), which need clean water. Eels (Anguilla), crucian carp (Carasius) and some others also tolerate a considerable degree of pollution. 

It is a matter of general agreement that plants preferring warm and dry conditions are more resistant to emissions than other species. However, in the case of pollution by petroleum substances and natural gas, xerothermic species are shown to be sensitive to the impact of petroleum substances. On all the polluted areas, the number of species is reduced. Certain sensitive plant species are suppressed or even completely destroyed and only tolerant species can survive. 

Monaci et al. (1997) performed a lichen-biomonitoring study in Siena by means of two different methods. The pattern of air quality in the study area was examined on the basis of the in situ frequency of different species of epiphytic lichens, i.e. using their species-specific sensitivity to the complex mixture of phytotoxic pollutants in the urban environment. The distribution of trace elements was evaluated quantitatively by an analysis of thalli of a tolerant species, P. caperata, known to be a reliable bioaccumulator of persistent atmospheric pollutants. The values obtained for Al, Ba, Cr, Cu, Fe, Pb and S were significantly higher in Sienese lichens over and above controls. Traffic was found to be the major source of atmospheric pollution. The pattern of trace-elemental deposition did not always coincide with air quality. lAP values were found to reflect essentially the emission of gaseous phytotoxic pollutants in the urban environment. 

The history of an activated-sludge biomass affects the way in which it will respond when a new pollutant is introduced species that cannot tolerate the substance fail to reproduce and grow and tend to die off, whereas more tolerant species consume the food supply and grow and reproduce. 

In practice, the extent to which a freshwater system has been stressed by pollutants can be determined through an examination of the presence or absence of specific chironomid species with known pollution tolerances. Finer scale analyses of relative abundances can also provide clues to the presence of specific stressors. For instance, high abundance of a chironomid species such as Dicrotendipes nervosus frequently indicates the presence of abundant decomposable organic matter, whereas species such as Cricotopus bicinctus are found more commonly in systems with high levels of inorganic contaminants (7). Since even closely related species can have distinct pollution tolerances, the need for proper identifications is particularly important and useful (d). 

McClellan K, Altenburger R, Schmltt-Jansen M (2008) Pollution-induced community tolerance as a measure of species interaction in toxicity assessment. J Appl Ecol 45 1514... 

Schmitt-Jansen M, Altenburger R (2005) Predicting and observing responses of algal communities to photosystem Il-herbicide exposure using pollution-induced community tolerance and species-sensitivity distributions. Environ Toxicol Chem 24 304... 

Susceptibility of vegetation to air pollutant injury is reportedly influenced by many climatic factors, edaphic factors, genetic variability, and by structural and biochemical variations in the plant. Observed differences in susceptibility have prompted numerous attempts to prepare lists of plant species according to susceptibility or tolerance to specific air pollutants. It has become apparent that such lists are frequently inaccurate because the differential in susceptibility within a single variety or cultivar may be as great as that between species. 

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