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Schafer R.B.,RMIT University | Schafer R.B.,University of Koblenz-Landau | Kefford B.J.,RMIT University | Kefford B.J.,University of Technology, Sydney | And 7 more authors.
Science of the Total Environment | Year: 2011

We compiled a database on a priori selected traits for South-East Australian freshwater macroinvertebrate families and used this data for the development of a biotic indicator for the detection of the effects of salinisation on freshwater communities (SPEARsalinity) and for the adaptation of the existing SPEARpesticides index for South-East Australian taxa. The SPEARsalinity indicator showed a reasonably high relationship (0.38≤r2≤0.5) with salinity in terms of logarithmic electrical conductivity (log EC) using field biomonitoring data from 835 pools and riffle sites in Victoria and South Australia. Several other biotic indexes that were calculated for comparison purpose exhibited a lower relationship with log EC. In addition, SPEARsalinity was the only indicator that did not respond to other water quality variables and was therefore most selective. We used log EC data and modelled pesticide exposure for sites in Victoria in concert with SPEARsalinity and the existing SPEARpesticides index to assess whether pesticides interacts with effects of salinity on invertebrate communities and vice versa. No interaction with pesticides was found for the effect of log EC on SPEARsalinity, whereas EC interacted with the estimated pesticide exposure on the invertebrate communities. To foster the development of further trait-based ecological indicators, we suggest a conceptual model that predicts response traits based on the disturbance regime and disturbance mode of action of the stressor. Biotic indicators based on a priori selected traits represent a promising biomonitoring tool even for regions where ecological information is scarce. © 2011 Elsevier B.V.

Kefford B.J.,RMIT University | Kefford B.J.,University of Technology, Sydney | Marchant R.,Museum of Victoria | Schafer R.B.,RMIT University | And 3 more authors.
Environmental Pollution | Year: 2011

The risk of chemicals for ecological communities is often forecast with species sensitivity distributions (SSDs) which are used to predict the concentration which will protect p% of species (PC p value). However, at the PC p value, species richness in nature would not necessary be p% less than at uncontaminated sites. The definition of species richness inherent to SSDs (contaminant category richness) contrasts with species richness typically measured in most field studies (point richness). We determine, for salinity in eastern Australia, whether these definitions of stream macroinvertebrate species richness are commensurable. There were strong relationships (r 2 ≥ 0.87) between mean point species, family and Ephemeroptera, Trichoptera and Plecoptera species richness and their respective contamination category richness. Despite differences in the definition of richness used by SSDs and field biomonitoring, their results in terms of relative species loss from salinity in south-east Australia are similar. We conclude that in our system both definitions are commensurable. © 2010 Elsevier Ltd. All rights reserved.

Candeiro C.R.A.,Federal University of Uberlandia | Rich T.,Museum of Victoria | Rich T.,Monash University
Journal of South American Earth Sciences | Year: 2010

The Turonian-Maastrichtian beds of the Bauru Group, western São Paulo State (Brazil), have yielded a diverse biota. The nine species of mesoecrocodilians are all mesosuchians. There is a single frog, a Neubatrachia. The vertebrates include, four types of fishes, a neobatrachian frog, an anilioid snake, two lizard, six species of podocnemid turtles, nine species of mesosuchian mesoecrocodilians three theropods, two birds, five titanosaurid sauropods, and one mammalian. The invertebrates include one cyclo, one cyclophoroid and eight pulmonates. Plants are represented by only two carophyte species. The biota from western São Paulo State is one the most diverse of the Late Cretaceous in Brazil. The biota from this area confirms that Bauru Group was connected to Patagonia and other Gondwanan areas during the Late Cretaceous. © 2009 Elsevier Ltd.

Clark M.R.,NIWA - National Institute of Water and Atmospheric Research | Rowden A.A.,NIWA - National Institute of Water and Atmospheric Research | Schlacher T.,University of The Sunshine Coast | Williams A.,CSIRO | And 7 more authors.
Annual Review of Marine Science | Year: 2010

In this review of seamount ecology, we address a number of key scientific issues concerning the structure and function of benthic communities, human impacts, and seamount management and conservation. We consider whether community composition and diversity differ between seamounts and continental slopes, how important dispersal capabilities are in seamount connectivity, what environmental factors drive species composition and diversity, whether seamounts are centers of enhanced biological productivity, and whether they have unique trophic architecture. We discuss how vulnerable seamount communities are to fishing and mining, and how we can balance exploitation of resources and conservation of habitat. Despite considerable advances in recent years, there remain many questions about seamount ecosystems that need closer integration of molecular, oceanographic, and ecological research. © 2010 by Annual Reviews.

Thresher R.,CSIRO | Althaus F.,CSIRO | Adkins J.,California Institute of Technology | Gowlett-Holmes K.,CSIRO | And 9 more authors.
PLoS ONE | Year: 2014

Assemblages of megabenthos are structured in seven depth-related zones between ∼700 and 4000 m on the rocky and topographically complex continental margin south of Tasmania, southeastern Australia. These patterns emerge from analysis of imagery and specimen collections taken from a suite of surveys using photographic and in situ sampling by epibenthic sleds, towed video cameras, an autonomous underwater vehicle and a remotely operated vehicle (ROV). Seamount peaks in shallow zones had relatively low biomass and low diversity assemblages, which may be in part natural and in part due to effects of bottom trawl fishing. Species richness was highest at intermediate depths (1000-1300 m) as a result of an extensive coral reef community based on the bioherm-forming scleractinian Solenosmilia variabilis. However, megabenthos abundance peaked in a deeper, low diversity assemblage at 2000-2500 m. The S. variabilis reef and the deep biomass zone were separated by an extensive dead, sub-fossil S. variabilis reef and a relatively low biomass stratum on volcanic rock roughly coincident with the oxygen minimum layer. Below 2400 m, megabenthos was increasingly sparse, though punctuated by occasional small pockets of relatively high diversity and biomass. Nonetheless, megabenthic organisms were observed in the vast majority of photographs on all seabed habitats and to the maximum depths observed - a sandy plain below 3950 m. Taxonomic studies in progress suggest that the observed depth zonation is based in part on changing species mixes with depth, but also an underlying commonality to much of the seamount and rocky substrate biota across all depths. Although the mechanisms supporting the extraordinarily high biomass in 2000-2500 m depths remains obscure, plausible explanations include equatorwards lateral transport of polar production and/or a response to depth-stratified oxygen availability. © 2014 Thresher et al.

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