Nutrient Cycling and Primary Production in Port Hacking, New South Wales

1978 ◽  
Vol 29 (6) ◽  
pp. 803 ◽  
Author(s):  
BD Scott
Keyword(s):  
Primary Production ◽  
Water Column ◽  
New South ◽  
Heavy Rain ◽  
Sedimentation Rates ◽  
Nutrient Regeneration ◽  
Seasonal Differences ◽  
Salinity Stratification ◽  
South Wales ◽  
Lower Water Column

The changes in the concentrations of nitrate, phosphate and silicate in a marine-dominated estuarine basin are described and related to the changes in the physical properties of the water and the primary production. The consumption of oxygen and nutrient regeneration in the lower water column were directly related to density differences in the lower water column, and to the primary production. The regeneration of nutrients was related to the consumption of oxygen, with seasonal differences in the regeneration of nitrate and silicate. Increased rates of nutrient regeneration during salinity stratification after heavy rain were attributed to increased sedimentation rates.

Dispersal of seeds of giant Sporobolus spp. after ingestion by grazing cattle

1995 ◽  
Vol 35 (3) ◽  
pp. 353 ◽  
Author(s):  
TS Andrews
Keyword(s):  
New South ◽  
Heavy Rain ◽  
North Coast ◽  
The North ◽  
Fresh Manure ◽  
Grazing Cattle ◽  
South Wales ◽  
Cattle Faeces ◽  
Viable Seeds ◽  
Number Of Seeds

Samples of fresh cattle faeces were taken from 2 grazing paddocks on the North Coast of New South Wales. One paddock was heavily infested with giant Parramatta grass (GPG, Sporobolus indicus var. major) and the other paddock had a medium-light infestation. Fifty-two and 14 viable GPG seeds/kg were recovered from the dung samples collected in May from these paddocks, respectively. Seeds of GPG and giant rat's tail grass (GRTG, S. pyramidalis) were fed to caged Friesian heifers in 2 experiments, and the time taken for all of the seeds to be excreted was measured: 4 days in experiment 1 and 7 days in experiment 2. Consequently, a 7-day withholding period is suggested for cattle grazing pastures infested with giant sporobolus. The number of viable seeds excreted was estimated as a proportion of seeds fed to each heifer using average viability of seeds recovered, concentration of viable seeds collected daily, and daily manure weights. Based on this, the number of seeds ingested by gazing stock was estimated to be 8300 and 2200 seeds/head.day for the paddocks with heavy and medium-light infestation, respectively. Manure collected 2 and 3 days after feeding had the highest concentrations of viable seeds. This manure was placed outdoors in styrofoam boxes and left for 7 months. No GPG seedlings or plants were present in the manure after this time, and further subsampling of the manure indicated that no viable seeds remained. Processes that disperse fresh manure, such as heavy rain or the hosing down of transport vehicles, may allow successful germination and emergence of giant sporobolus seeds. However, where dung pats are left intact for some months, establishment of giant sporobolus plants is unlikely. Adhesion to machinery and the hair of stock are likely to be more important causes of dispersal of giant sporobolus than ingestion by stock.

Mineral nitrogen fluctuations in soils under improved pasture in Southern New South Wales

1962 ◽  
Vol 13 (6) ◽  
pp. 1059 ◽  
Author(s):  
JR Simpson
Keyword(s):  
New South ◽  
New South Wales ◽  
Heavy Rain ◽  
Early Spring ◽  
Mineral Nitrogen ◽  
Nitrate Accumulation ◽  
South Wales ◽  
Native Pasture ◽  
Autumn And Winter ◽  
Improved Pasture

Soils under improved pasture on the Southern Tableland of New South Wales accumulated nitrate in substantial quantities during the summer and autumn. In this respect they behaved quite unlike the pasture soils which have been studied in most of the earlier literature, and they resembled cultivated fallow soils, which usually accumulate nitrate at the same time of the year. The nitrate was produced mainly in the top inch of soil; ammonium also accumulated under certain conditions. The precise sequence of climatic events, particularly the period of drying between consecutive wettings, was of primary importance in the nitrate accumulation. The nitrate produced during summer and early autumn disappeared from the topsoil after heavy rain in autumn and winter. The seasons could therefore be distinguished as a nitrogen-rich summer and autumn, a nitrogen-depleting winter, and a nitrogen-poor early spring, with an increasing supply of mineral nitrogen during late spring. No appreciable fluctuations in mineral nitrogen were found in soils resown directly from native pasture with less than 0.10% total nitrogen at 0-2 in.

Nutrient partitioning in a clay-based surface flow wetland

1995 ◽  
Vol 32 (3) ◽  
pp. 203-209 ◽  
Author(s):  
P. W. Adcock ◽  
G. L. Ryan ◽  
P. L. Osborne
Keyword(s):  
Water Column ◽  
New South ◽  
Plant Litter ◽  
Surface Flow ◽  
Nitrogen And Phosphorus ◽  
Overlying Water ◽  
Living Plant ◽  
South Wales ◽  
Nutrient Partitioning ◽  
Nitrogen Phosphorus

A constructed, clay-based, surface flow wetland located in Byron Bay, New South Wales, Australia, was studied to determine the relative importance of living plant tissue, plant litter, sediment, and the water column as nutrient stores. The nitrogen, phosphorus and carbon contents of each nutrient compartment were determined throughout the wetland. The nitrogen and phosphorus content of the plants was higher at the inlet end of the wetland and declined with distance away from it. Nutrient levels in the sediment and water column did not vary significantly with distance through the wetland. Phosphorus concentrations in the sediments were high, but plants were shown to be responsible for the majority of nutrient accumulation from this system. The plants had failed to penetrate the clay substrate and a solid mat of adventitious roots had developed in the overlying water. In essence the plants, mainly grasses, were growing hydroponically.

Ecology of the Swamp Wallaby (Wallabia-Bicolor) in Northeastern New-South-Wales .1. Diet

1986 ◽  
Vol 13 (3) ◽  
pp. 355 ◽  
Author(s):  
CJ Hollis ◽  
CJ Hollis ◽  
JD Robertshaw ◽  
JD Robertshaw ◽  
RH Harden ◽  
...  
Keyword(s):  
Plant Species ◽  
New South ◽  
New South Wales ◽  
The Other ◽  
Seasonal Differences ◽  
South Wales ◽  
North Eastern ◽  
Wallabia Bicolor ◽  
Swamp Wallaby

The diet of the swamp wallaby Wallabia bicolor was determined by identifying plant fragments from the forestomachs of animals collected at two sites (Diamond Flat and the Styx River State Forest) in forests on the edge of the eastern escarpment of the Great Dividing Range in north-eastern New South Wales. Seventy-seven and 72 genera of plants were recorded in the diets at the two sites respectively. The dietary items were grouped into six categories, the overall occurrence of which ranged frcm forbs (26%), ferns (19%), shrubs (19%), grasses, sedges and rushes (17%) and fungi (15%) to vines (3%). There were broad similarities in the diets of the animals from both sites, though there were some seasonal differences both within and between sites, the most marked being an increase in grasses, sedges and rushes and a decrease in fungi in spring. It is suggested that fungi may be an important source of nitrogen during the other seasons. The wide array of plant species eaten by the swamp wallaby indicates that it is a generalist rather than specialist feeder, and more of a browser than the larger macropodids.

Distribution of the cyanobacterial toxins cylindrospermopsin and deoxycylindrospermopsin in a stratified lake in north-eastern New South Wales, Australia

2009 ◽  
Vol 60 (1) ◽  
pp. 25 ◽  
Author(s):  
Sally Everson ◽  
Larelle Fabbro ◽  
Susan Kinnear ◽  
Geoff Eaglesham ◽  
Paul Wright
Keyword(s):  
Water Column ◽  
New South ◽  
New South Wales ◽  
Chemical Species ◽  
Cylindrospermopsis Raciborskii ◽  
Relative Distribution ◽  
Cyanobacterial Cell ◽  
Cyanobacterial Toxins ◽  
South Wales ◽  
North Eastern

This paper describes the vertical water column distribution of the cyanobacterial toxins cylindrospermopsin and deoxycylindrospermopsin in a water body containing the cyanobacteria Aphanizomenon ovalisporum and Cylindrospermopsis raciborskii. The study site was Cobaki Village Lake, a small stratified anthropogenic lake in north-eastern New South Wales, Australia. Water quality analysis indicated that stratification and oxygenation of the water column were significant in both the distribution of the cyanobacterial populations and their associated toxin concentrations. Toxin was distributed throughout the entire water column, but the highest concentrations were recorded in the hypolimnion. Maximum toxin concentrations were detected in February 2007 (38.2 μg L–1 cylindrospermopsin (CYN) and 42.2 μg L–1 deoxy-CYN). The relative distribution of CYN and deoxy-CYN paralleled the distribution of NH3H and NOX within the water column, with oxygenated chemical species dominating above 15 m and de-oxygenated chemical species dominating below 15 m. Cyanobacterial cell concentrations were highest in the oxic, warm and low conductivity waters of the epilimnion and cyanobacterial species succession was associated with nutrient and trace-metal depletion in this surface layer. These research findings are directly relevant to the management of water supplies affected by toxic blue-green algal blooms, particularly with respect to the considered placement of off-take devices to avoid layers of cyanobacterial cell and toxin concentrations.

Temporal and spatial variation in recruitment and growth of medusae of the jellyfish, Catostylus mosaicus (Scyphozoa : Rhizostomeae)

2003 ◽  
Vol 54 (2) ◽  
pp. 117 ◽  
Author(s):  
Kylie A. Pitt ◽  
Michael J. Kingsford
Keyword(s):  
New South ◽  
Heavy Rain ◽  
Late Winter ◽  
Conservative Estimate ◽  
Temporal And Spatial Variation ◽  
South Wales ◽  
Temporal And Spatial ◽  
Time Of Year ◽  
Lake Illawarra ◽  
Cohort Analyses

The timing of recruitment and growth of medusae of the commercially harvested jellyfish, Catostylus mosaicus (Scyphozoa), was examined over a period of 8 years at Botany Bay and 2.5 years at Lake Illawarra in New South Wales, Australia. Recruitment events occurred sporadically during December and between March and July at Botany Bay and between February and July at Lake Illawarra. Recruitment did not occur during late winter or spring at either location, although small numbers of recruit medusae could potentially occur during any time of year. Despite anecdotal observations that recruitment sometimes occurred after periods of heavy rain, we found no correlation between the timing of recruitment and rainfall in Botany Bay over a period of 8 years. Cohort analyses indicated growth of small medusae was very rapid (max. 4.81 mm day–1), with growth rates decreasing as medusae grew larger. Medusae appeared to grow faster at Botany Bay than Lake Illawarra. A conservative estimate indicated medusae of C. mosaicus can live for up to 13 months.

Mire Development and Environmental Change, Barrington Tops, New South Wales, Australia

1987 ◽  
Vol 27 (1) ◽  
pp. 73-81 ◽  
Author(s):  
J.R. Dodson
Keyword(s):  
Environmental Change ◽  
Climatic Change ◽  
New South ◽  
New South Wales ◽  
Environmental Data ◽  
Early Holocene ◽  
Sedimentation Rates ◽  
South Wales ◽  
Comparison Of The Results ◽  
Regional Climatic Change

AbstractSediments began accumulating in nine mires on Barrington Tops, on the Northern Tablelands of New South Wales, before 11,000 yr B.P., and peat became common in the region by 8600 yr B.P. Sedimentation rates were low, but increased markedly about 3000 yr B.P. and again around 500 yr B.P. as a result of regional climatic change. A comparison of the results with other environmental data from the region suggests that conditions in the early Holocene were warmer and moister than at present, but that cooler and drier environments developed about 3000 yr B.P. In the last 500 yr a slight warming and either increased precipitation or cloudiness has become evident.

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