Reconnaissance limnology of Tasmania VII. Coastal lagoons of Bass Strait Islands, with reference to endemic microflora and microfauna

Coastal lagoons of the principal islands of Bass Strait, between Australia's mainland and Tasmania, were sampled in two summers. Many, particularly those of low to moderate salinity, contain relatively rich assemblages of microinvertebrates and some endemic Australian freshwater algae. Several species of testate amoebae and rotifers could not be referred to known morphotypes and are probably new species. The presence of certain species on islands of Bass Strait provides a link between populations in mainland Australia and others in Tasmania. Those lagoons are identified that, by virtue of catchments or buffer zones clothed in native vegetation, are favourable for the survival of a native and partly endemic microbiota.

Reconnaissance limnology of Tasmania VIII. Tasmanian coastal lagoons - epicentres of endemism in the Australian aquatic microbiota

Two clusters of coastal lagoons, one near Strahan on Tasmania's west coast, the other near St Helens on the north-east coast, are the prime known epicentres of novelty and endemism in the Australian freshwater algal flora. The algae inhabiting these acid, dystrophic lagoons have a very limited distribution. Other dystrophic lagoons may have one or two, but not all, of this suite of endemics. The Strahan dune lakes, especially Lake Garcia, also have the greatest microfaunal diversity yet recorded from any Tasmanian waterbody, including several endemic species. The St Helens sites are less rich in species of microfauna, perhaps because of climatic differences or perhaps because of less intensive sampling there, but they, too, contain endemic taxa. The lagoons in both areas lie outside the formal protection of national parks, but present land management does provide a measure of protection.

Endocrine disrupting chemicals accumulate in earthworms exposed to sewage effluent

Endocrine disrupting chemicals (EDCs) can alter endocrine function in exposed animals. Such critical effects, combined with the ubiquity of EDCs in sewage effluent and potentially in tapwater, have led to concerns that they could be major physiological disruptors for wildlife and more controversially for humans. Although sewage effluent is known to be a rich source of EDCs, there is as yet no evidence for EDC uptake by invertebrates that live within the sewage treatment system. Here, we describe the use of an extraction method and GC–MS for the first time to determine levels of EDCs (e.g., dibutylphthalate, dioctylphthalate, bisphenol-A and 17β-estradiol) in tissue samples from earthworms (Eisenia fetida) living in sewage percolating filter beds and garden soil. To the best of our knowledge, this is the first such use of these techniques to determine EDCs in tissue samples in any organism. We found significantly higher concentrations of these chemicals in the animals from sewage percolating filter beds. Our data suggest that earthworms can be used as bioindicators for EDCs in these substrates and that the animals accumulate these compounds to levels well above those reported for waste water. The potential transfer into the terrestrial food chain and effects on wildlife are discussed.

Sewage disposal and ocean pollution : contradictory world views as a theme in policy change

Explores the process of state policy making in the area of sewage disposal and pollution management. Argues that contradictory world views form the milieu of understanding through which environmental policy is shaped. The dynamic tension between two contradictory views is explained mainly through events within two regional water authorities in Victoria during the 1980s.. The analysis suggests that a process of incremental change in the shaping of environmental policy is taking place.

Utilization of bacteriophage NCIMB-10645 of Serratia marcescens strain NCIMB-10644 as a tracer of pollution from an ocean sewage outlet

Bacteriophage NCIMB-10645 of Serratia marcescens (NCIMB-10644) was assessed as a tracer of aquatic contamination with the intention of using it at the Black Rock ocean outfall in South Eastern Australia. Growth conditions and a liquid culture growth curve were assessed. The bacteriophage was subjected to survival trials and a method of concentrating NCIMB-10645 developed. NCIMB-10645 was assessed as a tracer at Deakin University then released from the Black Rock Sewage Treatment Plant. Contamination movement away from the treatment plant was found to be predominantly affected by Easterly wind conditions.

Sorption and Fractionation of Copper in soil at a sewage irrigation farm in Australia

Copper (Cu) is an important heavy metal to be considered in soil contamination, because high concentrations of copper in soil produce toxic effects and may accumulate in plant tissues. In Australia's oldest sewage irrigation farm, located in Werribee, Victoria, soil in the land filtration area is contaminated by Cu. However, Cu content in herbage tissues is in the normal range and has been trending downward since 1979. Therefore, studies on the sorption capacity and sequential extraction of Cu in soil at the Werribee Farm is of significance, not only for better understanding the mechanism of transport, chemical processes, and plant uptake of Cu, but also in providing information for the practical management of sewage farm soils. Methods of combining sorption isotherms with sequential extraction procedures were adopted, and the results showed that the soil in the land filtration area at Werribee Farm has a high sorption capacity for Cu, and distribution coefficients, K_f of Cu, were 629 L kg^-1 in surface soils (0-20 cm) and 335 L kg^-1 in subsurface soils (20-40 cm). The sequential extraction fractions demonstrate that exchangeable and carbonate fractions are very low, only comprising 3.49 to 5.49% of total copper. The other fractions are also discussed. This characteristic of Cu in soil is related to the low concentration of Cu in plant tissues.

Detection of endocrine disrupting chemicals in aerial invertebrates at sewage treatment works

Endocrine disrupting chemicals (EDCs) constitute a diverse group of chemical compounds which can alter endocrine function in exposed animals. Whilst most studies have focussed on exposure of wildlife to EDCs via aquatic routes, there is the potential for transfer into the terrestrial food chain through consumption of contaminated prey items developing in sewage sludge and waste water at sewage treatment works. In this study, we determine levels of EDCs in aerial insects whose larval stages develop on percolating filter beds at sewage treatment works. We compare absolute concentrations of known EDCs with those collected from aquatic environments not exposed to sewage effluent outflow. Our findings document for the first time that aerial invertebrates developing on sewage filter beds take up a range of chemicals thought to be incorporated from the sewage effluent, which act as endocrine disruptors. For two synthetic chemicals (17α-ethinylestradiol and butylated hydroxy aniline), concentrations were significantly higher in insects captured around percolating filter beds than sites over 2 km from the nearest sewage works. A number of species of insectivorous bats and birds, some of which are declining or threatened, use sewage works as principle foraging sites. We calculate approximate exposure levels for a species of bat known to forage within sewage works and suggest that further research is warranted to assess the ecological implications of consuming contaminated invertebrate prey

Environmental impact assessment of the sewage outfall at Davis Station, East Antarctica

During the summer 2009/10, an environmental impact assessment of the sewage outfall was conducted at Davis Station, East Antarctica. An investigation of the nature and extent of impacts to the marine environment associated with current sewage treatment and effluent discharge practices included ecological surveys of macrobiological communities, physico-chemical analysis of sediments and receiving waters, microbiological analysis, and histopathological analysis of fish. Ecotoxicological testing using local invertebrates to determine effluent toxicity was interpreted alongside dispersal modelling data of the discharge plume to determine the potential extent of impacts and inform recommendations on the level of treatment and dilution of sewage required to minimise impacts. No evidence of impacts was detected on soft sediment infaunal or epifaunal communities, and only low levels of contamination and accumulation were found in sediments and waters in the immediate vicinity of the outfall and in the direction of primary current flow. In contrast, sterol biomarkers and faecal coliforms (E. coli) were detected in sediments collected adjacent to the outfall and in most water column samples. Marine invertebrates (Abatus and Laternula) also tested positive for E. coli and antibiotic resistance mechanisms were present in Laternula indicating the introduction and dispersal through the water column of foreign microbes and bacteria associated with human effluent. Fish (Trematomus bernacchii) close to the outfall showed significant histological alterations in all major tissues (liver, gill, gonad, muscle) resulting from exposure to sewage. Effluent was toxic to amphipods (Paramoera walkeri) and microgastropods (Skenella paludionoides), with reduced survival in concentrations as low as 3.125% over a 21d exposure period. Acute effects were also observed in both species following 24h exposure, with 100% mortality at the highest effluent concentrations tested (68%). The application of these results to support and guide decisions regarding the planned installation of new sewage treatment facilities at Davis will be discussed.

Portfolio delivery approach to township sewage treatment facilities in China: a case study

 The wide need for sewage treatment facilities at the township level across China implies an emerging niche market for water and sanitation developers, investors and financiers. However this potential market is difficult to enter with traditional financing and delivery methods, because township sewage features small amount, volatile quantity, geographically scattering, immature fee charging system, weak affordability, and lack of capacities. A group of concession sewage treatment projects collectively implemented by a private company in the Changsha County of Hunan Province under the so called ‘Changsha Model’ provided innovative solutions. This cases study first examined the portfolio approach in terms of multiple delivery method integration, technology, and centralized control system, and evaluated the replicability of the new model. Practices and lessons learned from the case were then presented and summarized that can be applied to the following township sewage treatment facility development. Last, the Changsha Model was compared with similar infrastructure portfolio delivery solutions applied in the US.

CERAMIC MATERIAL FROM SEWAGE SLUDGE AS SUPPORT MATERIAL SUPPLY WATER FILTRATION

This study shows a possibility of using municipal sewage sludge after thermal treatment in the production of a filtering material to water treatment. Due to the fast urbanization and implementation of high standards for effluent in many countries in recent years, the sewage sludge is being produced in an ever increasing amount. Therefore, the use of sludge is a suitable solution for the expected large quantity of sludge. Dehydration of sludge was performed by controlled heating at temperatures of 1100 degrees C, 850 degrees C, 650 degrees C, 350 degrees C for 3 hours. After thermal treatment the sludge was characterized by X-ray fluorescence, TG/DTG/DTA, residue solubilization and residue lixiviation tests. The aim of the present work was to observe, thought the characterization techniques, if the treated sewage sludge is or not adequate to be used as filter material to water treatment. It will be verified which treatment temperature of the sludge offer possibility to its use in water treatment without carrying pollutants in concentrations out of the standards.