Entity

Time filter

Source Type

Taylors Beach, Australia

Mika S.,University of New England of Australia | Hoyle J.,Macquarie University | Kyle G.,Macquarie University | Howell T.,Griffith University | And 15 more authors.
Ecology and Society | Year: 2010

Many river restoration projects fail. Inadequate project planning underpins many of the reasons given for failure (such as setting overly ambitious goals; selecting inappropriate sites and techniques; losing stakeholder motivation; and neglecting to monitor, assess, and document projects). Another major problem is the lack of an agreed guiding image to direct the activities aimed at restoring the necessary biophysical and ecological processes within the logistic constraints of on-ground works. Despite a rich literature defining the components of restoration project planning, restoration ecology currently lacks an explicit and logical means of moving from the initial project vision through to on-ground strategies. Yet this process is fundamental because it directly links the ecological goals of the project to the on-ground strategies used to achieve them. We present a planning process that explicitly uses an interdisciplinary mechanistic model of disturbance drivers and system responses to build from the initial project vision to the implementation of on-ground works. A worked example on the Upper Hunter River in southeastern Australia shows how understanding catchment history can reveal disturbance and response mechanisms, thus facilitating process-based restoration. © 2010 by the author(s). Source


Gazeau F.,French National Center for Scientific Research | Gazeau F.,University Pierre and Marie Curie | Parker L.M.,University of Western Sydney | Comeau S.,Northridge | And 7 more authors.
Marine Biology | Year: 2013

Over the next century, elevated quantities of atmospheric CO2 are expected to penetrate into the oceans, causing a reduction in pH (-0.3/-0.4 pH unit in the surface ocean) and in the concentration of carbonate ions (so-called ocean acidification). Of growing concern are the impacts that this will have on marine and estuarine organisms and ecosystems. Marine shelled molluscs, which colonized a large latitudinal gradient and can be found from intertidal to deep-sea habitats, are economically and ecologically important species providing essential ecosystem services including habitat structure for benthic organisms, water purification and a food source for other organisms. The effects of ocean acidification on the growth and shell production by juvenile and adult shelled molluscs are variable among species and even within the same species, precluding the drawing of a general picture. This is, however, not the case for pteropods, with all species tested so far, being negatively impacted by ocean acidification. The blood of shelled molluscs may exhibit lower pH with consequences for several physiological processes (e.g. respiration, excretion, etc.) and, in some cases, increased mortality in the long term. While fertilization may remain unaffected by elevated pCO2, embryonic and larval development will be highly sensitive with important reductions in size and decreased survival of larvae, increases in the number of abnormal larvae and an increase in the developmental time. There are big gaps in the current understanding of the biological consequences of an acidifying ocean on shelled molluscs. For instance, the natural variability of pH and the interactions of changes in the carbonate chemistry with changes in other environmental stressors such as increased temperature and changing salinity, the effects of species interactions, as well as the capacity of the organisms to acclimate and/or adapt to changing environmental conditions are poorly described. © 2013 Springer-Verlag Berlin Heidelberg. Source


Parker L.M.,University of Western Sydney | Ross P.M.,University of Western Sydney | O'Connor W.A.,Port Stephens Fisheries Center | Borysko L.,University of Western Sydney | And 2 more authors.
Global Change Biology | Year: 2012

It is essential to predict the impact of elevated Pco 2 on marine organisms and habitats to anticipate the severity and consequences of future ocean chemistry change. Despite the importance of carry-over effects in the evolutionary history of marine organisms, few studies have considered links between life-history stages when determining how marine organisms will respond to elevated Pco 2, and none have considered the link between adults and their offspring. Herein, we exposed adults of wild and selectively bred Sydney rock oysters, Saccostrea glomerata to elevated Pco 2 during reproductive conditioning and measured the development, growth and survival response of their larvae. We found that elevated Pco 2 had a negative impact on larvae of S. glomerata causing a reduction in growth, rate of development and survival. Exposing adults to elevated Pco 2 during reproductive conditioning, however, had positive carry-over effects on larvae. Larvae spawned from adults exposed to elevated Pco 2 were larger and developed faster, but displayed similar survival compared with larvae spawned from adults exposed to ambient Pco 2. Furthermore, selectively bred larvae of S. glomerata were more resilient to elevated Pco 2 than wild larvae. Measurement of the standard metabolic rate (SMR) of adult S. glomerata showed that at ambient Pco 2, SMR is increased in selectively bred compared with wild oysters and is further increased during exposure to elevated Pco 2. This study suggests that sensitive marine organisms may have the capacity to acclimate or adapt to elevated Pco 2 over the next century and a change in energy turnover indicated by SMR may be a key process involved. © 2011 Blackwell Publishing Ltd. Source


Parker L.M.,University of Western Sydney | Ross P.M.,University of Western Sydney | O'Connor W.A.,Port Stephens Fisheries Center | Portner H.O.,Alfred Wegener Institute for Polar and Marine Research | And 2 more authors.
Biology | Year: 2013

Elevations in atmospheric carbon dioxide (CO2 are anticipated to acidify oceans because of fundamental changes in ocean chemistry created by CO2 absorption from the atmosphere. Over the next century, these elevated concentrations of atmospheric CO2 are expected to result in a reduction of the surface ocean waters from 8.1 to 7.7 units as well as a reduction in carbonate ion (CO3 2- concentration. The potential impact that this change in ocean chemistry will have on marine and estuarine organisms and ecosystems is a growing concern for scientists worldwide. While species-specific responses to ocean acidification are widespread across a number of marine taxa, molluscs are one animal phylum with many species which are particularly vulnerable across a number of life-history stages. Molluscs make up the second largest animal phylum on earth with 30,000 species and are a major producer of CaCO3. Molluscs also provide essential ecosystem services including habitat structure and food for benthic organisms (i.e., mussel and oyster beds, purification of water through filtration and are economically valuable. Even sub lethal impacts on molluscs due to climate changed oceans will have serious consequences for global protein sources and marine ecosystems. © 2013 by the authors; licensee MDPI, Basel, Switzerland. Source


Baumgartner L.J.,Narrandera Fisheries Center | Boys C.A.,Port Stephens Fisheries Center | Stuart I.G.,Arthur Rylah Institute for Environmental Research | Zampatti B.P.,SARDI Aquatic Sciences Center
Australian Journal of Zoology | Year: 2010

To provide passage for migratory native fish, a series of 14 vertical-slot and lock fishways are being constructed on the Murray River in south-eastern Australia. Three of these vertical-slot fishways, at Locks 7, 9 and 10, have a conservative slope (1V:32H) and are designed with internal hydraulics suitable for the passage of a broad size range of fish (30-1000 mm long). An assessment of these fishways was performed using a combined trapping survey and passive integrated transponder (PIT) approach to determine fishway effectiveness at passing an entire fish community. Fish were trapped within the three fishways between 2004 and 2006, where a total of 13626 individuals comprising 13 species were collected from 48 sample days (24h each). Trapping data revealed that the three fishways successfully passed fish within the target size range, though significantly greater numbers of individuals smaller (10-29mm long) than the target size range could not ascend. PIT tagging revealed important information on fishway ascent times, descent times, seasonality and diel behaviour of medium and large fish. Although each method alone had advantages and disadvantages, the dual assessment approach was useful as it permitted an assessment of fishway success and also provided insights into migratory fish behaviour. © CSIRO 2010. Source

Discover hidden collaborations