PubMed | University of Aveiro, Federal University of Tocantins and Level 10 Capital
Type: | Journal: Chemosphere | Year: 2015
A main source of uncertainty currently associated with environmental risk assessment of chemicals is the poor understanding of the influence of environmental factors on the toxicity of xenobiotics. Aiming to reduce this uncertainty, here we evaluate the joint-effects of two pesticides (chlorpyrifos and mancozeb) on the terrestrial isopod Porcellionides pruinosus under different soil moisture regimes. A full factorial design, including three treatments of each pesticide and an untreated control, were performed under different soil moisture regimes: 25%, 50%, and 75% WHC. Our results showed that soil moisture had no effects on isopods survival, at the levels assessed in this experiment, neither regarding single pesticides nor mixture treatments. Additivity was always the most parsimonious result when both pesticides were present. Oppositely, both feeding activity and biomass change showed a higher sensitivity to soil moisture, with isopods generally showing worse performance when exposed to pesticides and dry or moist conditions. Most of the significant differences between soil moisture regimes were found in single pesticide treatments, yet different responses to mixtures could still be distinguished depending on the soil moisture assessed. This study shows that while soil moisture has the potential to influence the effects of the pesticide mixture itself, such effects might become less important in a context of complex combinations of stressors, as the major contribution comes from its individual interaction with each pesticide. Finally, the implications of our results are discussed in light of the current state of environmental risk assessment procedures and some future perspectives are advanced.
Baker-Gabb D.,wildlife ecologist PO Box 131 |
Antos M.,Level 10 Capital |
Brown G.,Arthur Rylah Institute for Environmental Research
Ecological Management and Restoration | Year: 2016
A monitored population of the critically endangered Plains-wanderer (Pedionomus torquatus) on Victoria's Northern Plains declined by over 90% between 2010 and 2012 following an unusually wet year which led to flooding, excess grass growth and a major change in the structure of native grasslands. The Plains-wanderer population remained very low on private land during 2013 and 2014 when dry conditions prevailed and domestic stock overgrazed most of its favoured grasslands on red soil. Numbers also remained very low on public reserves despite grassland structure gradually improving there by 2014. In 2015, the population partially recovered in some grasslands protected from overgrazing. Grassland structure is critically important for Plains-wanderer conservation. The 'golf ball technique' proved to be a quick and effective method for measuring grassland structure; it offers a means of accelerating responses to habitat change because it can be easily used by land managers. © 2016 Ecological Society of Australia.
Preece N.,Charles Darwin University |
Harvey K.,Coonawarra Base |
Hempel C.,Level 10 Capital |
Woinarski J.C.Z.,Charles Darwin University
Ecological Management and Restoration | Year: 2010
Summary: The Top End region of the Northern Territory, Australia, is noted for its relatively unmodified natural state. To gain some insight into the potential for maintaining ecosystem health in this region we undertook a study that assessed the distribution of weeds across very extensive transects. This weed survey was distinct from other studies in that many of the sample sites were distant from tracks or other infrastructure. Twenty-one weed species were recorded along 2000 km of transects. Weeds were reported from 18.7% of the 718 sample points. The incidence of weeds was found to be significantly associated with land tenure, being highest on pastoral lands and peri-urban areas, and very low on Aboriginal lands. The incidence of weeds increased significantly with increasing levels of infrastructure and with increasing proximity to watercourses. There are three main conclusions from this study. First, much of the Top End, particularly remote Aboriginal lands, has exceptionally low levels of weed infestation. Secondly, in such areas, given the relatively small extent of vegetation change through weed invasion, maintenance or re-imposition of traditional fire regimes should be achievable. Thirdly, there is substantial potential for spread of weeds to remote areas, with such spread most likely to occur through increased penetration by infrastructure. Importantly this study indicates that there is still opportunity to prevent widespread weed invasion across the Top End, which is timely given the current Government consideration of the potential for the region to support future agricultural expansion and the fast-paced development of mining, oil and gas resources. © 2010 Ecological Society of Australia.
Ewing C.P.,Level 10 Capital |
Catterall C.P.,Griffith University |
Tomerini D.M.,Griffith University
Ecological Management and Restoration | Year: 2013
Community-based ecological restoration (CBR) has been encouraged by government funding schemes worldwide to help reverse ecosystem degradation, although many observers have questioned their longer-term outcomes. We investigated the ecological and social outcomes of community-based revegetation projects in an urban context, using the case study of all CBR groups located within 25 km of the Brisbane CBD which had been funded during 1997-2008 by the Australian Government's Natural Heritage Trust program to undertake revegetation works and which were also available for interview (N = 9 groups). First we reviewed the funding allocation within the region. Second, we conducted rapid on-ground assessments of vegetation outcomes at 10 project sites several years after works were completed, which showed that the detectable area of established revegetation averaged 75% of the area planned, and the achieved revegetation areas varied greatly, both in total and in relation to cost. Third, we undertook thematic analysis of semi-structured interviews with key group members, revealing that groups viewed the NHT scheme's short-term funding and lack of administrative flexibility as being largely incompatible with both quantitative monitoring (which groups did not prioritise) and longer-term maintenance of sites for successful vegetation establishment. Interactions with local governments were considered important to success, but internally-conflicting policies of local and state governments, together with unforeseen site disturbances, acted to limit the achievement of projects' revegetation goals. Volunteer involvement and motivation were an important part of groups' activities. Overall, these CBR projects achieved modest short term environmental benefits together with a range of social benefits. There is a need for new CBR models aimed at maximising both environmental and social outcomes. © 2013 Ecological Society of Australia.
Shima J.S.,Victoria University of Wellington |
McNaughtan D.,Victoria University of Wellington |
Strong A.T.,Victoria University of Wellington |
Strong A.T.,Level 10 Capital
Marine Biology | Year: 2015
Intraspecific variation in coral colony growth forms is common and often attributed to phenotypic plasticity. The ability of other organisms to induce variation in coral colony growth forms has received less attention, but has implications for both taxonomy and the fates of corals and associated species (e.g. fishes and invertebrates). Variation in growth forms and photochemical efficiency of massive Porites spp. in lagoons of Moorea, French Polynesia (17.48°S, 149.85°W), were quantified in 2012. The presence of a vermetid gastropod (Ceraesignum maximum) was correlated with (1) reduced rugosity of coral colonies and (2) reduced photochemical efficiency (Fv/Fm) on terminal “hummocks” (coral tissue in contact with vermetid mucus nets) relative to adjacent “interstitial” locations (tissue not in contact vermetid mucus nets). A manipulative field experiment confirmed that the relative growth rate of coral tissue was greater in interstices than hummocks when vermetids were present and similar (but with a trend for faster growth on hummocks) when vermetids were absent. Collectively, these results indicate that vermetid gastropods interact (presumably via their mucus nets) with coral colony architecture to impair photochemical efficiency, reduce growth rates of specific portions of a coral tissue, and induce a smoothed colony morphology. Given that structural complexity of coral colonies is an important determinant of “habitat quality” for many other species (fishes and invertebrates), these results suggest that the vermetid gastropod, C. maximum (with a widespread distribution and reported increases in density in some portions of its range), may have important indirect effects on many coral-associated organisms. © 2015, Springer-Verlag Berlin Heidelberg.
Davis N.E.,University of Melbourne |
Di Stefano J.,University of Melbourne |
Coulson G.,University of Melbourne |
Whelan J.,Parks Victoria |
Wright J.,Level 10 Capital
Wildlife Research | Year: 2016
Context. Restoration of disturbed vegetation communities commonly involves altering vegetation composition and structure, attributes that can influence the suitability of habitat for fauna. Feedbacks may occur whereby changes to the vegetation affect mammalian herbivores, and unintended changes may prevent managers from achieving conservation goals. Aims. To understand how vegetation management affects habitat use by five mammalian herbivores, namely eastern grey kangaroo (Macropus giganteus), swampwallaby (Wallabia bicolor), common wombat (Vombatus ursinus), European rabbit (Oryctolagus cuniculus) and hog deer (Axis porcinus). Methods. A management experiment (mechanical slashing of the encroaching shrub Leptospermum laevigatum) at Wilsons Promontory National Park, Australia, created slashed swales in addition to untreated dune and scrub woodland. In each vegetation stratum, we estimated the cover of L. laevigatum and quantified herbivore abundance by counting the standing crop of faecal pellets. Key results. Relative to untreated vegetation, mechanical slashing of L. laevigatum substantially reduced cover of this species above 200 cm, but increased its cover below 30 cm. On the basis of faecal-pellet counts, multispecies use of managed and unmanaged parts of the landscape differed substantially, with the differences principally driven by higher abundance of European rabbits and eastern grey kangaroos at slashed sites. Conclusions. The responses of three grazing species (kangaroo, rabbits and wombats) to vegetation management were predicted well by prior knowledge of diet and habitat preferences. This was not the case for the browser (swamp wallaby), nor for the grazer that consumes substantial amounts of browse in the study area (hog deer), and additional knowledge of the processes underlying their responses to vegetation change is required. Implications. Our findings highlighted that vegetation management can influence herbivore abundances in the managed system. An improved understanding of these associations will allow vegetation management plans to incorporate herbivore responses. © The authors 2016.
Hipgrave D.B.,United Nations Childrens Fund China Country Office |
Assefa F.,United Nations Childrens Fund Zimbabwe Country Office |
Winoto A.,Level 10 Capital |
Sukotjo S.,Level 10 Capital
Public Health Nutrition | Year: 2012
Objective Distribution of breast milk substitutes (BMS) after the 2006 Yogyakarta earthquake was uncontrolled and widespread. We assessed the magnitude of BMS distribution after the earthquake, its impact on feeding practices and the association between consumption of infant formula and diarrhoea among infants and young children.Design One month after the earthquake, caregivers of 831 children aged 0-23 months were surveyed regarding receipt of unsolicited donations of BMS, and on recent child-feeding practices and diarrhoeal illness. Setting Community-level survey in an earthquake-affected district. Subjects Primary caregivers of surveyed children.Results In all, 75 % of households with an infant aged 0-5 months and 80 % of all households surveyed received donated infant formula; 76 % of all households received commercial porridge and 49 % received powdered milk. Only 32 % of 0-5-month-old infants had consumed formula before the earthquake, but 43 % had in the 24 h preceding the survey (P < 0•001). Consumption of all types of BMS was significantly higher among those who received donated commodities, regardless of age (P < 0•01). One-week diarrhoea incidence among those who received donated infant formula (25•4 %) was higher than among those who did not (11•5 %; relative risk = 2•12, 95 % CI = 1•34, 3•35). The rate of diarrhoea among those aged 12-23 months was around five times the pre-earthquake rate.Conclusions There were strong associations between receipt of BMS and changes in feeding practices, and between receipt of infant formula and diarrhoea. Uncontrolled distribution of infant formula exacerbates the risk of diarrhoea among infants and young children in emergencies. © 2011 The Authors.
Coventry J.,Australian National University |
Andraka C.,Sandia National Laboratories |
Pye J.,Australian National University |
Blanco M.,CSIRO |
Fisher J.,Level 10 Capital
Solar Energy | Year: 2015
This paper examines the potential of sodium receivers to increase the overall solar-to-electricity efficiency of central receiver solar power plants, also known as solar tower systems. It re-visits some of the key outcomes and conclusions from past sodium receiver experiments, in particular those at Sandia National Laboratories and Plataforma Solar de Almeria in the 1980s, and discusses some current development activities in the area. It also discusses research in sodium receivers with a liquid-vapour phase change (heat pipes and pool boilers), to explore whether technologies developed for dish-Stirling systems have applicability for solar tower systems. Lessons learnt from experience in the nuclear industry with liquid sodium systems are discussed in the context of safety risks. © 2015 Elsevier Ltd.
Cardoso D.N.,University of Aveiro |
Santos M.J.G.,University of Aveiro |
Santos M.J.G.,Level 10 Capital |
Soares A.M.V.M.,University of Aveiro |
Loureiro S.,University of Aveiro
Chemosphere | Year: 2015
The application of molluscicides baits on the soil surface is the most common practice to control terrestrial gastropods. There seems to be a gap in the accurate evaluation of molluscicidal baits effects to soil arthropods, since their hazard to non-target organisms has been considered low after mixing baits into soil. In this work the ecotoxicological effects of two molluscicide baits (metaldehyde and methiocarb) to the collembolan Folsomia candida were evaluated using two different approaches: (1) molluscicidal baits were applied to the top soil once and only at the beginning of the exposure and avoidance behaviour and reproduction were evaluated; and (2) baits were replaced by new ones after 14-d of exposure, simulating the recommended application rate recommended by the manufacturer and reproduction was assessed (repeated/pulse exposure). A preference for the side contaminated for methiocarb was observed but the distribution of collembolans in the avoidance test with metaldehyde was random. Exposure to metaldehyde resulted in a significant increase in mortality. For methiocarb, a reduction in the juveniles produced but no acute effects were observed. In the bait pulse test, the toxic effects of each chemical was significantly increased compared with the single exposure test, for all treatments used (both reproduction and mortality). In summary, molluscicides have an adverse effect on F. candida, with severe effects on their behaviour (only for methiocarb), reproduction and survival (for both), which can lead to population collapse with time. © 2015 .