Information
Nitrogen and phosphorous in runoff from small catchments in the Queensland Murray Darling Basin increases with intensity of land use
Level 1 General description
Purpose:
The purpose of this study was to determine the effect of land use and soil type on nitrogen and phosphorous concentrations evident in runoff from catchments in the Queensland Murray Darling Basin.
Methods (brief)
Nitrogen and Phosphorous levels in rainfall and runoff samples were collected over three years for thirty-one small catchments (<10 ha in size), each with a particular land use and soil type combination and from three sets of larger nested catchments (3 - 200000 ha) with mixed land use/soils in the Queensland Murray Darling Basin (QMDB).
Key findings (brief)
- Export of N and P from all the single land use/soil type catchments was positively correlated with soil fertility and increased as land use intensity increased.
- Nutrient export rates for the nested catchments did not correlate well to land use.
Table 2. Average suspended sediment and nutrient concentrations for Toowoomba nested catchments (Titmarsh et al. 2009)
|
Catchment |
Area |
Average suspended sediment g/L |
Average Total Nitrogen mg/L |
Average Total Nitrogen suspended mg/L |
Average Total Nitrogen dissolved mg/L |
Average Total Phosphorus, mg/L |
Average Total Phosphorous dissolved mg/L |
Average Total Phosphorus suspended mg/L |
|
Gowrie Creek Willowburn |
4400 |
2.50 |
3.60 |
2.35 |
1.28 |
1.24 |
0.06 |
1.22 |
|
Gowrie Creek Willem’s Road |
4900 |
3.79 |
12.05 |
4.52 |
7.52 |
3.79 |
1.08 |
2.08 |
|
Gowrie Creek Oakey |
14200 |
3.82 |
13.25 |
6.28 |
6.98 |
4.02 |
0.94 |
3.08 |
|
Oakey Creek Fairview |
197000 |
1.99 |
13.73 |
4.63 |
8.44 |
2.66 |
0.38 |
2.28 |
Location
Toowoomba region
Related studies
The following sites were part of the same study - Killarney, Greenmount, Pittsworth, Theodore, Goondiwindi, Wallumbilla, Inglewood, Stanthorpe, Charleville and Goomburra.