Technical annual report 2000-01
Dept. of Regional Development, Primary Industry, Fisheries and Resources technical annual report; Department of Regional Development, Primary Industry, Fisheries and Resources technical and annual report; Reports; PublicationNT; Technical bulletin (Northern Territory. Dept. of Primary Industry and Fisheries) ; no. 295
2001-10
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Date:2001-10
English
Agriculture -- Northern Territory -- Periodicals; Fisheries -- Northern Territory -- Periodicals
Dept. of Primary Industry and Fisheries
Darwin
Technical bulletin (Northern Territory. Dept. of Primary Industry and Fisheries) ; no. 295
0158-2763
Check within Publication or with content Publisher.
https://hdl.handle.net/10070/223369
https://hdl.handle.net/10070/687151
Technical Annual Report 2000/01 17 Table 1. Current (prior to fertiliser application), critical and potentially desirable soil nutrient levels Nutrient level mg/kg Element Current Critical Desired Excess P 12.0 20.0 30.0 S 6.4 10.0 10.0 K 51.7 110.0 190.0 220.0 Ca 233.3 220.0 500.0 750.0 Mg 31.7 40.0 70.0 80.0 Mn 38.0 30.0 50.0 Cu 0.3 1.5 1.5 Zn 2.8 1.5 1.5 B 0.2 1.4 1.5 Table 1 displays the current status of the soil before fertiliser was applied, the critical levels considered necessary for peanut production and the desired optimal level. Table 1 also suggests levels, which would be considered to be excessive (K, Ca and Mg only). The excessive levels have been calculated. In reality it is likely that our cation exchange capacity (CEC) is so low (1.8 mEq/100g) that it would not be possible to achieve these actual levels in the soil for any length of time. The pH of the soil ranges from 7.0 (at 0-15 cm) to 5.6 (at a depth of 30-40 cm). Table 2. Quantity of elements required (kg/ha) Element Critical Desired Excess K 43.7 103.7 126.2 Ca 0.0 200.3 387.8 Mg 6.2 28.7 36.2 Table 2 displays the amount of each element (kg/ha) required to attain the levels specified in Table 1. The aim is to vary the level considered critical, desired or excessive. This has been calculated allowing for the current levels in the soil and taking into account the bulk density of the surface layer. The calculations are based on the volume of soil occupying a 5 cm deep layer. Table 3. Levels of fertiliser applied (kg/ha) Fertiliser used Critical Desired Excess MOP (50% K) 87.5 207.5 252.5 GYPSUM (18.7% Ca) 0.0 992.0 1907.0 GRANOMAG (50% Mg) 12.5 57.5 72.5 MOP =Muriate of Potash Table 4. Treatment description Treatment Number Element 1 2 3 4 5 6 7 8 K current critical excess critical critical critical critical excess Ca current current critical desired excess current current excess Mg current current current current current critical desired excess Planting was on 24/3/2000.