Generation and decay of hydrogen peroxide in estuarine waters

1988 ◽  
Vol 39 (3) ◽  
pp. 289 ◽  
Author(s):  
R Szymczak ◽  
TD Waite
Keyword(s):  
Hydrogen Peroxide ◽  
New South ◽  
River Estuary ◽  
Early Morning ◽  
Molar Absorptivity ◽  
Laboratory Studies ◽  
South Wales ◽  
Production Of Hydrogen ◽  
Bottom Waters ◽  
Rate Of Decay

Apart from its central role in photosynthesis, one of the most dramatic effects of light in marine and freshwater systems is its ability to generate reactive chemical intermediates. Of these, hydrogen peroxide is one of the more stable and easily detected. Aspects of the generation and decay of hydrogen peroxide in the Port Hacking River estuary, New South Wales, have been investigated in a number of field and laboratory studies. Peroxide concentrations in surface waters in the early morning are relatively uniform over the estuary and typically less than 35 nM, whereas concentrations in mid-afternoon in excess of 100 nM have been observed. Variation of peroxide concentration with depth in the deep basins of Port Hacking is dependent on the extent of structure within the water column, with little mixing of surface- generated peroxide into poorly-illuminated bottom waters under stratified conditions. Laboratory studies confirmed that light induces the production of hydrogen peroxide, the initial rate of production increasing with increasing molar absorptivity of the filtered water sample. Filtration of samples had little effect on the generation of hydrogen peroxide but dramatically reduced the rate of decay of photogenerated hydrogen peroxide.

Contributions to the Biology of Mulga. II. Germination

1971 ◽  
Vol 19 (1) ◽  
pp. 39 ◽  
Author(s):  
PB Preece
Keyword(s):  
Arid Zone ◽  
New South ◽  
Germination Rate ◽  
Ambient Air ◽  
Laboratory Studies ◽  
South Wales ◽  
Carbon Dioxide Concentrations ◽  
Germination Behaviour ◽  
One Year ◽  
Acacia Aneura

Investigations into the germination behaviour of seed of the widespread Australian arid zone leguminous tree Acacia aneura Benth. are described. Hardseededness has been overcome in routine laboratory studies, but attempts to understand the mechanism by which it is overcome in nature were unsuccessful. The seed germinates equally well in the dark and in the light within the temperature range 15-36°C. Temperatures between 20 and 30° are optimal for germination, and carbon dioxide concentrations up to 5 % increase the germination rate above that displayed in ambient air. A simple model has been developed which suggests that seed of this species should have been available and should have germinated in c. one year in every nine, since records began in parts of western New South Wales where mulga regeneration is absent.

Above- and below-ground biomasses of two species of mangrove on the Hawkesbury River estuary, New South Wales

1997 ◽  
Vol 48 (2) ◽  
pp. 147 ◽  
Author(s):  
Neil Saintilan
Keyword(s):  
New South ◽  
New South Wales ◽  
River Estuary ◽  
Avicennia Marina ◽  
Above Ground Biomass ◽  
Aegiceras Corniculatum ◽  
South Wales ◽  
Below Ground ◽  
Mangrove Communities ◽  
Intertidal Environments

Above- and below-ground biomasses of two species of mangrove, Avicennia marina and Aegiceras corniculatum, were estimated in a range of intertidal environments along the Hawkesbury River. Estimates of biomass of Avicennia communities in freshly accreted brackish substrata were in the order of 40 kg m–2, the highest figure ever recorded for temperate mangrove communities. The above-ground biomass communities of each species declined with increasing substratum salinity, whereas root/shoot ratios increased with increasing substratum salinity.

A Comparison of Bats and Birds as Pollinators of Banksia integrifolia in Northern New South Wales, Australia.

1995 ◽  
Vol 18 (1) ◽  
pp. 9
Author(s):  
D.P. Woodside ◽  
G.H. Pyke
Keyword(s):  
New South ◽  
New South Wales ◽  
Temporal Patterns ◽  
Early Morning ◽  
Melaleuca Quinquenervia ◽  
Spatial And Temporal Patterns ◽  
Common Item ◽  
South Wales ◽  
Forested Areas ◽  
Daily Patterns

We captured Queensland Blossom Bats (Syconycteris australis) feeding at the flowers of Banksia integrifolia during the night and several honeyeater species feeding at the same flowers during the day. Nearby were flowering Melaleuca quinquenervia and various forested areas including littoral rainforest. Honeyeaters appear to be more frequent visitors to the Banksia flowers than Blossom Bats but less effective at transporting pollen. When they are feeding at Banksia flowers both birds and bats carry pollen on the parts of their bodies that contact successive inflorescences. Hence, both honeyeaters and bats are likely to be pollinators of B. integrifolia in our study area. However, the flowers produce nectar and dehisce pollen primarily at night, suggesting that Blossom Bats are more important than honeyeaters as pollinators of this plant. Banksia pollen was the most common item in the diet of the Blossom Bats during our study and the bats were able to digest the contents of this pollen. Interestingly, the diet of these animals also included relatively small amounts of Melaleuca pollen, fruit and arthropods. The spatial and temporal patterns of capture of the Blossom Bats suggested that Blossom Bats prefer to forage at Banksia flowers that are near to the forested areas and that adult bats may influence where and when younger bats feed. Banksia integrifolia appears to produce nectar mostly during the night and/or early morning in two different locations, one coastal and one on the tablelands, but shows different daily patterns of pollen anthesis in these locations.

How past sea-level changes can inform future planning: A case study from the Macleay River estuary, New South Wales, Australia

The Holocene ◽  
2014 ◽  
Vol 24 (11) ◽  
pp. 1591-1601 ◽  
Author(s):  
Sarah A McGowan ◽  
Robert GV Baker
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
New South ◽  
New South Wales ◽  
River Estuary ◽  
The Past ◽  
Case Study Area ◽  
South Wales ◽  
The Future

Climate change poses many challenges for the future management and development of the coastal zone. Uncertainties in the rate of future sea-level rise reduce our ability to project potential future impacts. This study seeks to further develop the past–present–future methodology proposed in Baker and McGowan and apply it to an additional case study, the Macleay River estuary, New South Wales (NSW), Australia. The past–present–future methodology uses evidence from the past, the Holocene and Pleistocene, to formulate a response function that can be used to project future sea-level heights. Three scenarios for 2100 were developed to emphasise the uncertainties surrounding future sea levels and the need to consider multiple sea-level rise scenarios when planning for the future: a best case (90 cm rise), mid-case (2.6 m rise) and worst case (5 m rise). Light detection and ranging (LiDAR) data were used to project each of the three scenarios onto the case study area of South West Rocks. The methodology was tested by using shell samples extracted from cores which were AMS dated to determine whether or not Holocene estuarine conditions correlated with the proposed future sea-level rise inundation scenarios. We also conducted an audit of potentially affected infrastructure and land uses, and proposed possible future adaptation strategies for the case study area.

Threat and stress in the Clarence River estuary of Northern New South Wales

Human Ecology ◽  
1981 ◽  
Vol 9 (4) ◽  
pp. 419-432 ◽  
Author(s):  
J. S. Burgess ◽  
Eric Woolmington
Keyword(s):  
New South ◽  
New South Wales ◽  
River Estuary ◽  
South Wales

Group SIze in the Eastern Grey Kangaroo, Macropus giganteus, and the Wallaroo, Macropus robustus

1982 ◽  
Vol 9 (2) ◽  
pp. 229 ◽  
Author(s):  
RJ Taylor
Keyword(s):  
Group Size ◽  
New South ◽  
New South Wales ◽  
Early Morning ◽  
Frequency Of Occurrence ◽  
South Wales ◽  
Grey Kangaroo ◽  
North Eastern

Data were collected on the occurrence of eastern grey kangaroos and wallaroos in groups on two properties (Lana and Newholme) in north-eastern New South Wales. The density of both species was higher on Lana than on Newholme. The frequency of occurrence of groups of different size was significantly different from that expected if the occurrence was random for both species. For the grey kangaroo on Lana, mean group size was smaller during early morning than during the rest of the day. Mean group size was significantly greater on Lana than on Newholme for both species, and smaller for wallaroos than for grey kangaroos on both properties. For both species, mean group size was significantly correlated with the density of kangaroos in each habitat.

Roosting and thermoregulatory behaviour of male Gould's long-eared bats, Nyctophilus gouldi: energetic benefits of thermally unstable tree roosts

2006 ◽  
Vol 54 (1) ◽  
pp. 57 ◽  
Author(s):  
Christopher Turbill
Keyword(s):  
Ambient Temperature ◽  
New South ◽  
Early Morning ◽  
Thermal Biology ◽  
Late Afternoon ◽  
Tree Cavities ◽  
South Wales ◽  
Temperature Telemetry ◽  
Thermoregulatory Behaviour ◽  
Torpor Bouts

Information about the thermal biology of bats in relation to their roosting behaviour is scant. I used temperature telemetry to locate roosts and record the thermoregulatory behaviour of male long-eared bats, Nyctophilus gouldi (9 g), during late spring in the Northern Tablelands of New South Wales. Bats roosted under bark and in tree cavities, where they typically experienced wide daily fluctuations in ambient temperature (Ta). On 13 out of 16 days, bats employed two torpor bouts per day, during the early morning and late afternoon, coinciding with times of low Ta. Heating of roosts during the day resulted in up to 20°C of passive re-warming before active arousal and provided high Ta around midday when bats were normothermic. By switching between torpor and normothermic thermoregulation according to the daily Ta cycle, male N. gouldi appear to gain an energetic advantage from choosing poorly insulated and often sun-exposed roosts.

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