scholarly journals Organic matter and benthic metabolism in euphotic sediments along shallow sub-tropical estuaries, northern New South Wales, Australia

2003 ◽  
Vol 33 ◽  
pp. 137-154 ◽  
Author(s):  
AJP Ferguson ◽  
BD Eyre ◽  
JM Gay
Keyword(s):  
Organic Matter ◽  
New South ◽  
New South Wales ◽  
Tropical Estuaries ◽  
Benthic Metabolism ◽  
South Wales

Limnological studies of waterfowl habitat in south-western New South Wales. II. Aquatic macrophyte productivity

1985 ◽  
Vol 36 (5) ◽  
pp. 707 ◽  
Author(s):  
SV Briggs ◽  
MT Maher
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Aquatic Macrophyte ◽  
New South ◽  
New South Wales ◽  
South Wales ◽  
Waterfowl Habitat ◽  
Dry Out ◽  
The Relationship ◽  
Wetland Flooding

Aquatic macrophyte productivity and soil organic matter were measured in two impermanent wetlands in south-western New South Wales. Macrophyte biomasses (≤463 g dry wt m-2) were similar to or higher than those in submerged communities elsewhere. Macrophyte productivities in both wetlands were greatest in the year following reflooding. But even in that year, macrophyte productivity in Lake Merrimajeel (the only wetland for which data are available) was considerably less than soil organic reserves before reflooding. It is suggested that these soil organic reserves directly contribute to the relationship between wetland flooding and waterfowl breeding, while macrophytes contribute indirectly by providing detritus for invertebrates. It is recommended that wetlands managed for waterfowl breeding should periodically dry out and reflood.

The intake and performance of cattle grazing irrigated pastures. 2. Effect of pasture length on growth of steers

1973 ◽  
Vol 13 (64) ◽  
pp. 477
Author(s):  
DW Hennessy
Keyword(s):  
Organic Matter ◽  
Growth Rates ◽  
Dry Matter ◽  
New South ◽  
New South Wales ◽  
Cattle Grazing ◽  
High Moisture ◽  
Moisture Contents ◽  
South Wales ◽  
And Performance

The organic matter intakes (OMI) and liveweight of twenty-four weaner steers grazing either short or long irrigated annual pastures were compared during May to November in 1964 and 1965 at Leeton, New South Wales. The OMI were estimated from determinations of faeces organic matter output using chromic oxide dilution, and of digestibility estimated from a faeces nitrogen-digestibility relationship for pen-fed cattle. Weaners that grazed the short or long pasture did not differ significantly in final liveweights (356 v.361 kg respectively, 1964; 357 v.361 kg, 1965) or OMI (4.99 v.5.42 kg day-1, 1964; 5.78 v.6.06 kg day-1, 1965) although available dry matter was less (P < 0.05) in short than in long pastures in both years. The OMI were commensurate with the 0.6 kg mean daily liveweight gains of weaners, which however were smaller than other reported growth rates, and an unsatisfactory production from the costly pastures. The reasons for the small liveweight gains are unknown but it is suggested that high moisture contents (85 per cent) of pastures restricted intake, or that high clover contents (58 per cent) caused bloating and rumen distension which thereby restricted intake.

Nutrient Cycling in a New South Wales Subtropical Rainforest: Organic Matter and Phosphorus

1989 ◽  
Vol 63 (6) ◽  
pp. 635-642 ◽  
Author(s):  
JOHN TURNER ◽  
MARCIA J. LAMBERT ◽  
JOSEPH KELLY
Keyword(s):  
Organic Matter ◽  
Nutrient Cycling ◽  
New South ◽  
New South Wales ◽  
South Wales

Nutrient distribution and cycling in a subtropical rainforest in New South Wales

2016 ◽  
Vol 64 (2) ◽  
pp. 100 ◽  
Author(s):  
Marcia Lambert ◽  
John Turner
Keyword(s):  
Organic Matter ◽  
Primary Productivity ◽  
Net Primary Productivity ◽  
New South ◽  
Nutrient Use Efficiency ◽  
New South Wales ◽  
Nutrient Distribution ◽  
South Wales ◽  
Nutrient Use ◽  
Use Efficiency

Subtropical rainforests in New South Wales (NSW) are distributed on the more fertile forest soils and are nutritionally distinct from the Eucalyptus forests in the same areas. The distribution, cycling of organic matter and nutrients and nutrient use efficiency in an Australian subtropical rainforest were studied and aspects were compared with reported Eucalyptus studies. The available nutrients were greatly in excess of the stand uptake or requirement. A single undisturbed plot within a research trial in mature forest was selected for the study. At the beginning of the study, the aboveground forest biomass was ~334 t ha–1 of organic matter and, 22 years later, there was 357 t ha–1, giving a net accumulation rate of 1.03 t ha–1 year–1, and net primary productivity of 13.0–14.6 t ha–1 year–1. Litterfall and forest-floor analyses indicated a very rapid turnover of organic matter, with an estimated half-life of ~0.5 years. The quantity of nutrients in the stand was high relative to other forest types in the area, with 1109.2 kg N ha–1, 62 kg P ha–1, 1999 kg Ca ha–1, 591 kg Mg ha–1 and 901 kg K ha–1. Nutrient requirement estimated as nutrient content of the current tissue was estimated to be 107, 5.3, 99, 26 and 61 kg ha–1 year–1 for N, P, Ca, Mg and K, respectively, and uptake defined as removal from the soil was estimated to be 112, 4.7, 128, 37 and 49 kg ha–1 year–1 for the same nutrients, the difference between these being net nutrient redistribution. Nutrient use efficiency (NUE), defined as net primary productivity (NPP) per requirement (t kg–1), was calculated to be 0.12, 2.43, 0.13, 0.50 and 0.21 for N, P, Ca, Mg and K, respectively; these values were low, for example, compared with mature E. pilularis, for which NPP was 0.20, 6.5, 0.43, 1.04 and 0.52 t kg–1 for N, P, Ca, Mg and K, respectively. Using NUE defined as NPP per uptake provided comparable estimates. The rainforest represents a forest growing with basically no nutrient limitations, and, as such, is a benchmark for forest nutrient distribution, cycling and NUE.

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