Bioassessment without reference sites: use of environmental filters to predict natural assemblages of river macroinvertebrates

Theoretical predictions of observed to expected ratios in RIVPACS-type predictive model assessments of stream biological condition

“…1) followed with an evaluation of perhaps the most comprehensive ecologically based typology of streams developed to date. In the same year, Chessman and Royal (2004; Fig. 1 Fig.…”

Water quality assessment of Portuguese streams: Regional or national predictive models?

“…The problem of determining reference conditions in regions that have been extensively modified has been considered by several authors (e.g., Reynoldson and Wright, 2000;Verdonschot and Nijboer, 2000;Chessman and Royal, 2004;Stoddard et al, 2006). The collection of more reference sites is a possibility but may not be possible because of the difficulty finding acceptable sites in this highly developed area of Portugal.…”

“…The collection of more reference sites is a possibility but may not be possible because of the difficulty finding acceptable sites in this highly developed area of Portugal. A promising alternative for the use of reference sites that could be applied in the littoral region of Portugal is that of environmental filters (Chessman and Royal, 2004). Filters are major components of the habitat patterns in streams (such as riverbed composition or flow regime) that exclude taxa of a regional pool from sites where the ranges of environmental conditions are incompatible with their preferences and tolerances.…”

Bioassessment in A Harsh Environment: A Comparison of Macroinvertebrate Assemblages at Reference and Assessment Sites in An Australian Inland River System

“…If this hypothesis is true, the measures should vary in a predictable manner among sites with different levels of particular anthropogenic disturbances, or in the same site after a human disturbances begins, changes in severity or is removed. Some such predictions have been verified statistically for SIGNAL (and to a lesser extent EPT) with sewage and urban runoff (Growns et al, 1995(Growns et al, , 1997) and a range of point and diffuse disturbances of varying severity (Metzeling et al, 2003;Chessman and Royal, 2004). For AUSRIVAS O/E, or its antecedents, some such predictions have been verified in instances of major urban pollution (Marchant et al, 1997) and gross trace metal contamination associated with historical mining (Sloane and Norris, 2003).…”