Phosphorus, nitrogen, and radionuclide retention and leaching from a Joel sand amended with red mud/gypsum

Journal Article · Sat Jan 01 00:00:00 EST 1994 · Communications in Soil Science and Plant Analysis; (United States)

DOI:https://doi.org/10.1080/00103629409369235· OSTI ID:6650617

McPharlin, L R ^[1]; Jeffery, R C ^[2]; Toussaint, L F ^[3]; Cooper, M ^[4]

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1. Dept. of Agriculture Western Australia, South Perth (Australia)
2. Chemistry Centre, East Perth (Australia)
3. Western Australia Dept. of Health, Nedlands (Australia)
4. Australian Radiation Labs., Yallambie, Victoria (Australia)

The leaching of phosphorus (P), nitrogen (N), and radionuclides [sup 232]Th, [sup 226]Ra, [sup 228]Ra, and [sup 40]K from Joel sands amended with red mud/gypsum (RMG) at 9 rates (0, 2, 4, 8, 16, 32, 64, 128, and 256 t/ha) was measured using columns. Intense leaching conditions (34 mm/day for 12 days) and a high rate of applied P (320 kg/ha as superphosphate) and N (680 kg/ha as ammonium nitrate) were used to simulate extremes of irrigated vegetable production on the Swan Coastal Plain. Addition of the highest rate of RMG (256 t/ha) reduced leaching of fertiliser P and ammonium-nitrogen (NH4-N) by 85% and 50%, respectively, compared with 0 t/ha after 12 days. At 64 t RMG/ha P leaching was reduced 50% compared with 0 t/ha. Nitrate-nitrogen (NO3-N) leaching was not affected by addition of RMG. Reduced leaching of NH4-N was attributed to an increase in cation exchange capacity of the soil with the addition of RMG. Bicarbonate-extractable P in the soil increased with rate of RMG to >50 [mu]g P/g soil at 256 t/ha. This indicates that soil testing of residual P could be used to reduce P inputs to vegetable crops after soils were amended with RMG. This would further reduce the impact of vegetable production on the water systems of the Swan Coastal Plain and extend the period of effectiveness of RMG amended soils. The increase in [sup 232]Th specific activity in Joel sand amended with RMG was well below statutory limits even at the highest rate. Neither [sup 40]K nor [sup 226]Ra were detectable in RMG amended sands up to 256 t RMG/ha. There was no evidence of leaching of [sup 226]Ra or [sup 228]Ra at any rate of RMG. These results suggest that the use of RMG amendment on commercial horticultural properties on the Swan Coastal Plain could be feasible. 30 refs., 7 figs., 2 tabs.

• OSTI ID: 6650617
• Journal Information: Communications in Soil Science and Plant Analysis; (United States), Vol. 25:17-18; ISSN 0010-3624
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
NITROGEN
LEACHING
PHOSPHORUS
RADIOISOTOPES
ENVIRONMENTAL TRANSPORT
SAND
IRRIGATION
SOILS
CULTIVATION
POTASSIUM 40
RADIUM 228
THORIUM 232
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALKA
ALKALINE EARTH ISOTOPES
ALPHA DECAY RADIOISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
DISSOLUTION
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
EVEN-EVEN NUCLEI
HEAVY NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LIGHT NUCLEI
MASS TRANSFER
NANOSEC LIVING RADIOISOTOPES
NONMETALS
NUCLEI
ODD-ODD NUCLEI
POTASSIUM ISOTOPES
RADIUM ISOTOPES
SEPARATION PROCESSES
SPONTANEOUS FISSION RADIOISOTOPES
THORIUM ISOTOPES
YEARS LIVING RADIOISOTOPES
540230* - Environment
Terrestrial- Radioactive Materials Monitoring & Transport- (1990-)