Organic pollution and its effects: a short-term transplant experiment to assess the ability of biological endpoints to detect change in a soft sediment environment

Abstract

A wide variety of endpoints or metrics are commonly employed in pollution monitoring situations but, to date, there have been very few experimental field studies aimed at assessing links between a putative pollutant and established soft sediment assemblages. We carried out a manipulative field experiment whereby intact assemblages were transplanted from control areas to sites adjacent to drains discharging secondary treated sewage effluent at 3 intertidal outfall locations in Port Phillip Bay, Victoria, Australia. We found that the ability of different measures to detect impacts varied, although multivariate methods were able to discriminate the effects of treatment, and population level measures tended to be more sensitive than assemblage level measures of abundance, biomass and diversity. Integrated measures, such as average individual biomass, were found to provide a sensitive detection tool plus an insight into the biological consequences of observed changes. We consider our findings in the light of conceptual models of pollution-induced change in soft sediment assemblages.

Variation in the response of intertidal infaunal invertebrates to nutrient additions: field manipulations at two sites within Port Phillip Bay, Australia

“…The power to detect differences was very low for both total biomass and the biomass:abundance (B:A) ratio, and Corophium insidiosum values are log 10 (x + 1) the high variability of the data may reflect the fact that we didn't make any adjustments for shell weights in molluscs. Previous work at the WTP site found the B:A ratio to provide a sensitive measure of change without adjusting for shell weights (Morris & Keough 2002). There were no effects of nutrient additions on the diversity measures (Table 4), yet although the diversity (H ') appeared lower in the control plots at the beginning of the experiment and remained lower throughout (Fig.…”

Fish track wastewater pollution to estuaries

“…Sewage is a complex chemical mixture comprising a cocktail of toxicants (Pantsar-Kallio et al 1999). Pollution impacts of sewage on aquatic biota are diverse and have been identified at all levels of ecological organisation, including inter alia: pathological tissue changes (Moore et al 2003), estrogenicity and other endocrine disruptions (Gagne´and Blaise 2003;Jobling and Tyler 2003), altered dynamics of populations exposed to sewage (Hindell and Quinn 2000), shifts in production and body-size spectra of communities , reduction in seagrass with knock-on effects on food webs (McClelland and Valiela 1998a), and changes to assemblage composition and structure (Archambault et al 2001; Morris and Keough 2002).…”

Influence of an estuarine plume and marine sewage outfall on the dynamics of coastal bacterioplankton communities

“…From a different perspective, organic and inorganic substrates discharged through sewage outfall are also an issue of concern and involve wider spatial ranges. Their impacts are found to cause changes in the size and structure of phytoplankton communities (Soltan et al 2001, Parnell 2003 and of soft sediment faunal assemblages (Morris & Keough 2002).…”

“…From a different perspective, organic and inorganic substrates discharged through sewage outfall are also an issue of concern and involve wider spatial ranges. Their impacts are found to cause changes in the size and structure of phytoplankton communities (Soltan et al 2001, Parnell 2003 and of soft sediment faunal assemblages (Morris & Keough 2002).Bacterioplankton are highly reactive towards organic matter (Taylor et al 2003) and inorganic nutrients (Torréton et al 2000). Extracellular degradation and nutrient uptake profiles are closely related to the quality and size of the pool of dissolved organic matter (Taylor et al 2003).…”