scholarly journals Catchment modelling of sediment, nitrogen and phosphorus nutrient loads with SedNet/ANNEX in the Tully - Murray basin

2009 ◽  
Vol 60 (11) ◽  
pp. 1091 ◽  
Author(s):  
J. D. Armour ◽  
L. R. Hateley ◽  
G. L. Pitt
Keyword(s):  
Biophysical Model ◽  
Nutrient Loads ◽  
Inorganic N ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Hill Slope ◽  
Eastern Australia ◽  
North Eastern ◽  
Wet Tropics ◽  
The Impact

A long-term, annual-average catchment biophysical model (SedNet/ANNEX) was used to calculate sediment, nitrogen (N) and phosphorus (P) loads in the Tully–Murray catchment of north-eastern Australia. A total of 119 000 t year–1 of suspended sediment, equivalent to 430 kg ha–1 year–1, was calculated to be exported to the Great Barrier Reef (GBR). Most of the sediment (64%) was generated from hill-slope erosion. The modelled load of dissolved inorganic N (1159 t year–1 or 4.2 kg N ha–1 year–1) was similar to that from other wet tropics catchments in Queensland with similar areas of sugarcane. Sugarcane produced 77% of this load. The annual loads of total N and total P were 2319 t and 244 t, respectively. Simulations (scenarios) were run to evaluate the impact of improved land management on pollutant loads to the GBR. A combination of improved cultivation and fertiliser management of sugarcane and bananas (99% of cropping land) and restoration of the most degraded riparian areas reduced sediment by 23 000 t year–1 (18%) and dissolved inorganic N by 286 t year–1 (25%). However, this reduction is much less than the reduction of 80% that may be needed in the catchment to meet target chlorophyll loads in the marine environment.

scholarly journals Future socioeconomic conditions may have a larger impact than climate change on nutrient loads to the Baltic Sea

AMBIO ◽  
2019 ◽  
Vol 48 (11) ◽  
pp. 1325-1336 ◽  
Author(s):  
Alena Bartosova ◽  
René Capell ◽  
Jørgen E. Olesen ◽  
Mohamed Jabloun ◽  
Jens Christian Refsgaard ◽  
...  
Keyword(s):  
Climate Change ◽  
Baltic Sea ◽  
Dynamic Modelling ◽  
Climate Change Scenarios ◽  
Nutrient Loads ◽  
The Baltic Sea ◽  
Nitrogen And Phosphorus ◽  
Socioeconomic Drivers ◽  
The Baltic ◽  
The Impact

Abstract The Baltic Sea is suffering from eutrophication caused by nutrient discharges from land to sea, and these loads might change in a changing climate. We show that the impact from climate change by mid-century is probably less than the direct impact of changing socioeconomic factors such as land use, agricultural practices, atmospheric deposition, and wastewater emissions. We compare results from dynamic modelling of nutrient loads to the Baltic Sea under projections of climate change and scenarios for shared socioeconomic pathways. Average nutrient loads are projected to increase by 8% and 14% for nitrogen and phosphorus, respectively, in response to climate change scenarios. In contrast, changes in the socioeconomic drivers can lead to a decrease of 13% and 6% or an increase of 11% and 9% in nitrogen and phosphorus loads, respectively, depending on the pathway. This indicates that policy decisions still play a major role in climate adaptation and in managing eutrophication in the Baltic Sea region.

scholarly journals Climate change impacts on nutrient loads in the Yorkshire Ouse catchment (UK)

2002 ◽  
Vol 6 (2) ◽  
pp. 197-209 ◽  
Author(s):  
F. Bouraoui ◽  
L. Galbiati ◽  
G. Bidoglio
Keyword(s):  
Climate Change ◽  
Assessment Tool ◽  
Swat Model ◽  
Climate Change Impacts ◽  
Climate Change Scenarios ◽  
Baseline Scenario ◽  
Nutrient Loads ◽  
Nitrogen And Phosphorus ◽  
Temperature And Precipitation ◽  
The Impact

Abstract. This study assessed the impact of potential climate change on the nutrient loads to surface and sub-surface waters from agricultural areas and was conducted using the Soil and Water Assessment Tool (SWAT) model. The study focused on a 3500 km2 catchment located in northern England, the Yorkshire Ouse. The SWAT model was calibrated and validated using sets of five years' measurements of nitrate and ortho-phosphorus concentrations and water flow. To increase the reliability of the hydrological model predictions, an uncertainty analysis was conducted by perturbing input parameters using a Monte-Carlo technique. The SWAT model was then run using a baseline scenario corresponding to an actual measured time series of daily temperature and precipitation, and six climate change scenarios. Because of the increase in temperature, all climate scenarios introduced an increase of actual evapotranspiration. Faster crop growth and an increased nutrient uptake resulted, as did an increase of annual losses of total nitrogen and phosphorus, however, with strong seasonal differences. Keywords: SWAT model, climate change, nutrient loads

Responses of Non-volant Mammals to Late Quaternary Climatic Changes in the Wet Tropics Region of North-eastern Australia

1997 ◽  
Vol 24 (5) ◽  
pp. 493 ◽  
Author(s):  
J. W. Winter
Keyword(s):  
Late Quaternary ◽  
Temperature Tolerance ◽  
Climatic Changes ◽  
Glacial Period ◽  
Profound Influence ◽  
Eastern Australia ◽  
North Eastern ◽  
Sclerophyll Forest ◽  
Wet Tropics ◽  
Glacial Periods

It is generally recognised that the distribution of vertebrates in rainforest and wet sclerophyll forest of the Wet Tropics region of north-eastern Australia is profoundly influenced by the formation of two rainforest refugia at the height of Pleistocene glacial periods. Anomalies in the distribution of non-volant mammals indicate that other events may be equally important. In this paper, past geographical occurrence of non-volant mammals is examined by equating the mammals’ known temperature tolerance with palaeoclimatic temperature zones. It is hypothesised that dispersal and vicariant phases taking place since the most recent glacial period have had a profound influence on current patterns of distribution. A major dispersal phase of cool-adapted species occurred after the glacial period, and continuous populations were subsequently fragmented into upland isolates by expansion of warm rainforest during the late post-glacial period. These upland isolates remain substantially unchanged to the present day. Species shared either with New Guinea or south-eastern Australia arrived in the region during the most recent post-glacial period. Clarification of periods of vicariance and dispersal provides a conceptual framework for testing relative divergences of populations within and between regions.

The impact of pasture development and grazing on water-yielding catchments in the Murray - Darling Basin in south-eastern Australia

2003 ◽  
Vol 43 (8) ◽  
pp. 817 ◽  
Author(s):  
W. H. Johnston ◽  
D. L. Garden ◽  
A. Rančić ◽  
T. B. Koen ◽  
K. B. Dassanayake ◽  
...  
Keyword(s):  
Perennial Grasses ◽  
Wagga Wagga ◽  
Deep Drainage ◽  
Nitrogen And Phosphorus ◽  
South Wales ◽  
Murray Darling Basin ◽  
Productivity Gain ◽  
Eastern Australia ◽  
Annual Grasses ◽  
The Impact

Experiments conducted from November 1996 to June 2002 in adjacent small catchments near Wagga Wagga, New South Wales, compared the productivity and hydrology of a heavily fertilised (about 30 kg phosphorus/ha.year) Phalaris aquatica (phalaris) pasture with that of a lightly fertilised (about 14 kg phosphorus/ha every second year) native grassland that contained a mixture of C3 and C4 perennial grasses, dominantly C4 Bothriochloa macra (redgrass).In summer, the native catchment was dominated by C4 perennial grasses while the phalaris catchment was dominated by annual C4 weedy species. During the cooler months, the phalaris pasture contained higher proportions of Vulpia spp., and other less-desirable annual grasses. Throughout the experiment, the native catchment was dominated by redgrass, whereas in the phalaris catchment the persistence of phalaris declined. Redgrass became prominent on the more arid aspects of the phalaris catchment as the experiment progressed.Pasture production in the phalaris catchment was higher in most seasons than the native catchment, which resulted in an overall stocking rate advantage of about 80%. The productivity gain per unit of P input was 0.4 for the phalaris catchment compared with 1 for the native catchment, implying that phosphorus was applied to the phalaris catchment at an excessive rate.During wet periods the native catchment produced substantially more runoff than the phalaris catchment, while in dry times it developed substantially larger soil water deficits. Runoff from the phalaris catchment was higher in suspended and dissolved nitrogen and phosphorus than for the native catchment. Higher runoff from the native catchment combined with its drier soil profile in summer indicated that its deep drainage potential was less than in the phalaris catchment.

scholarly journals Nitrogen and Phosphorus Balances Vary at the Whole-Farm, Field, and Within-Field Scales

2021 ◽  
Vol 2 ◽  
Author(s):  
Jonathan M. Berlingeri ◽  
Joseph R. Lawrence ◽  
S. Sunoj ◽  
Karl J. Czymmek ◽  
Quirine M. Ketterings
Keyword(s):  
N Uptake ◽  
Nutrient Balance ◽  
Corn Silage ◽  
Nitrogen And Phosphorus ◽  
Management Options ◽  
Total N ◽  
Available N ◽  
N Removal ◽  
The Impact ◽  
Total P

A field nutrient balance (supplied minus harvested) can be an effective, end-of-season management evaluation tool. However, development of guidance for balance-based management requires knowledge of variability in balance inputs. To contribute to development of such guidelines, we evaluated the impact of corn silage hybrid selection, nutrient management, and growing conditions on field nitrogen (N) balances and documented variability in N and phosphorus (P) balances at the whole-farm, field, within-field levels. Variability in N removal among hybrids was evaluated using hybrid trials (5 locations, 4 years each). Variability in farm and field balances (4 farms, 2 years each) and within-field balances (2 farms, 2 years each) was assessed as well. Nitrogen supply comprised soil N (soil type-specific book values), rotation N, past manure N, and current year N (fertilizer and/or manure). Total N balances included all current year manure N while available N balances considered only plant-available N from manure. Phosphorus balances were derived as total P applied minus P harvested. Yield explained 81% of the variability in N uptake across hybrids. Nitrogen uptake intensity (NUI; N uptake per unit of yield) varied across locations and years, averaging 4.3 ± 0.1 kg N/Mg for short-season hybrids [≤95 days-to-maturity (DTM)] vs. 4.1 ± 0.1 kg N Mg−1 for longer-season hybrids. Whole-farm N balances ranged from 139 to 251 kg N ha−1 for total N and 43 to 106 kg N ha−1 for available N. Phosphorus balances ranged from 28 to 154 kg P ha−1. Balances per field ranged from −8 to 453, −66 to 250 kg N ha−1, and −30 to 315 kg P ha−1 for total N, available N, and total P, respectively, while within-field balances showed even larger ranges. We conclude that (1) variability in corn silage N and P balances at field and within-field scales and across year is large, emphasizing the need for field and within-field (where feasible) evaluation tools and management options, and (2) feasible limits for N balances should include both total and available N.

Extensive range contraction predicted under climate warming for a gliding mammal in north-eastern Australia

2019 ◽  
Vol 41 (1) ◽  
pp. 99
Author(s):  
Fathimah Handayani ◽  
Ross L. Goldingay ◽  
Darren McHugh ◽  
Nicole Leslie
Keyword(s):  
Climate Warming ◽  
New South ◽  
South Eastern ◽  
Core Habitat ◽  
South Wales ◽  
Eastern Australia ◽  
North Eastern ◽  
Wet Tropics ◽  
Future Warming ◽  
Petaurus Australis

We used MaxEnt to model the current distribution of the yellow-bellied glider (Petaurus australis) and to predict the likely shift in the species’ future distribution under climate-warming scenarios in the Wet Tropics (WT) Bioregion in north Queensland and in the South-eastern Queensland (SEQld) Bioregion, which encompasses south-eastern Queensland and north-eastern New South Wales. Bioclimatic layers were used to generate models from 57 independent records in the WT and 428 records in SEQld. The modelled distribution of core habitat under current climate showed a good fit to the data, encompassing 91% and 88% of the records in each area, respectively. Modelling of future warming scenarios suggests that large contractions in distribution could occur in both bioregions. In the WT, 98% of core habitat is predicted to be lost under low warming (1°C increase) and 100% under high warming (2−3°C increase) by 2070. In SEQld, 80% of core habitat is predicted to be lost under low warming and 90% under high warming by 2070. These results suggest that this species is highly vulnerable to climate warming and highlight the importance of focusing conservation efforts at the bioregional scale. There is also a need to identify potential thermal refuges and ensure habitat connectivity.

scholarly journals Tree species distribution and its impact on soil properties, and nitrogen and phosphorus mineralization in a humid subtropical forest ecosystem of northeastern India

2009 ◽  
Vol 39 (1) ◽  
pp. 36-47 ◽  
Author(s):  
Jenpuiru Kamei ◽  
H. N. Pandey ◽  
S. K. Barik
Keyword(s):  
Soil Properties ◽  
Tree Species ◽  
Soil Parameters ◽  
Organic Carbon Content ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Species Dominance ◽  
Northeastern India ◽  
P Mineralization ◽  
The Impact

The impact of tree species on net N and P mineralization, and soil properties beneath their canopy were studied in a subtropical evergreen broad-leaved forest of northeastern India. Four types of experimental plots were identified based on tree species dominance. The first plot was dominated by Myrica esculenta Buch.-Ham. ex D. Don., the second by Rhododendron arboreum Sm., the third by Neolitsea cassia Koster., and the fourth was a mixed-species plot. Organic carbon content (3.11%) and NH4+-N concentration (11.40 μg·g–1) in the Rhododendron plot, pH (4.64) and total N content (0.89%) in the mixed plot, available P (5.16 μg·g–1) and NO3–-N (8.63 μg·g–1) concentrations in the Neolitsea plot were significantly higher (p < 0.001) than the other plots. All these soil parameters were lowest in the Myrica plot. The net N and P mineralization rates in an annual cycle across different plots ranged between 18.83 and 22.14 μg·g–1·month–1 and between 4.54 and 5.87 μg·g–1·month–1, respectively. The flux varied significantly (p < 0.001) among the plots, the lowest and highest being in the Myrica plot and mixed plots, respectively. The differences in soil properties and in net N and P mineralization among different species plots were related to litter quality and yield of the respective species as well as soil microenvironment.

Riekophlebia crocina, a new genus and species of Atalophlebiinae (Ephemeroptera: Leptophlebiidae) from the Wet Tropics bioregion of north-eastern Australia

Zootaxa ◽  
2009 ◽  
Vol 2063 (1) ◽  
pp. 64-68
Author(s):  
FAYE CHRISTIDIS
Keyword(s):  
New Genus ◽  
New Genus And Species ◽  
Eastern Australia ◽  
North Eastern ◽  
Wet Tropics

Riekophlebia crocina, a new genus and species, is described from Australia based on nymphs and adults. Riekophlebia belongs to a lineage that also includes the Australian genera Austrophlebioides, Kirrara, Manggabora and Tillyardophlebia.

Nitrogen and Phosphorus Limits for Nutrient Deficient Industrial Wastewaters

1991 ◽  
Vol 24 (3-4) ◽  
pp. 259-267 ◽  
Author(s):  
Christian H. Möbius
Keyword(s):  
Paper Industry ◽  
Treatment Plant ◽  
Pulp Mill ◽  
Operating Conditions ◽  
Inorganic N ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Industrial Wastewaters ◽  
Treated Effluent ◽  
Plant Optimization

For biological treatment of nutrient deficient industrial wastewaters, such as those of the pulp and paper industry, the addition of nitrogen and phosphorus is essential. As a certain surplus is necessary, both elements will be found in the effluent in varying concentrations. For the often used activated sludge treatment 5 parts of N and 1 part of P are said to be required for elimination of 100 parts of BOD. In-plant optimization generally leads to about 3.5 parts of N and 0.6 parts of P for 100 parts of BOD. In most plants N is added as urea and P as phosphoric acid. Optimized nutrient dosage aimed at stable operating conditions in the treatment plant generally gives average concentrations of 1 mg/l of both ammonia N and phosphate P in the treated effluent. However, due to fluctuations in loading and efficiency, variation coefficients of more than 100 % result in maximum concentrations in 24 hours mixed samples of more than 10 mg/l for N and P. Three examples of operational results are evaluated and discussed in detail. Water quality requirements will impose general limitations on N and P concentrations in treated effluents. Depending on the concentration limits and on the type of limited substance - i.e. ammonia N, total inorganic N or total N, phosphate P or total P - different strategies have to be developed. Nutrient dosage depending on the wastewater amount will become state of the art in the near future. The next step would be a loading dependent dosage. No results of technical operation are known which show the effluent concentrations obtainable with this technique. For cases in which limits cannot be met with this strategy the possibilities of nitrification, denitrification and biological P removal are discussed for nutrient deficient wastewaters. Results show that nitrification will work at low ammonia concentrations, however no steady nitrification will be obtained. Denitrification, on the other hand, seems to be difficult with low nitrate concentrations. At the present stage, no technical process meeting stringent total N or total inorganic N limits is known to exist for this type of effluent. Low P concentrations in the effluent can only be achieved by tertiary treatment, preferably final flocculation filtration processes. However, these will give rise to special problems in the treatment of pulp mill wastewaters, which are discussed in the paper.

scholarly journals The Impact of Feral Pigs on Rainforest Dynamics in North-Eastern Australia

2010 ◽  
Vol 24 ◽  
Author(s):  
Amanda , E. Elledge ◽  
Clive , A. McAlpine ◽  
Peter , J. Murray ◽  
Iain , J. Gordon
Keyword(s):  
Feral Pigs ◽  
Eastern Australia ◽  
North Eastern ◽  
The Impact
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