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A brief description of the inputs and outputs for the nutrient budget for each model follows.
Pastoral model
Nutrient budgets are available that relate to the farm as a whole or for each block within a farm.
The farm nutrient budget is the summation of the block nutrient budgets, weighted on an area basis. The farm nutrient budget includes transfers of nutrients to and from winter feed pads. On a block scale, the main transfer is from the block to the farm dairy or to the lanes. On a farm scale, transfers are to non-productive areas, namely the effluent pond and lanes.
| Nutrient Inputs |
|
Description |
|
| Fertiliser |
Nutrients in fertiliser applied |
| Effluent added |
Nutrients in effluent added to paddock as spray or as slurry. |
| Atmosphere |
Nutrients added in rainfall. For N, also includes the amount of N fixed by clover in pasture. |
| Irrigation |
Nutrients added in irrigation water. |
| Slow Release |
Nutrients released from soil minerals into the plant-available nutrient pool. |
Supplements
Brought In |
Nutrients in supplements brought on to the farm. |
| Nutrient Outputs |
|
Description |
|
| Product |
Net amount of nutrients removed in produce (milk, meat, fibre). |
| Transfer |
Movement of nutrients from productive parts of the farm to areas such as stock camps, sheds and lanes. |
| Supplements Removed |
Nutrients in supplements removed from the block or sold off the farm. |
| Atmospheric Loss |
Loss of N to the atmosphere by ammonia volatilisation and denitrification. |
| Leaching /Runoff |
Nutrients lost to ground (below the rooting zone) or surface water as leaching or as runoff. |
| Immobilistion / Absorption |
Net immobilisation of N, P or S in soil organic matter, or absorption of P into slowly available forms in the soil. |
| Change in Inorganic Soil Pool |
Change in inorganic soil pools. This is reflected in changes in soil test values. |
Cropping model
| Nutrient Inputs |
|
Description |
|
| Fertiliser |
Nutrients in fertiliser applied |
| Atmospheric |
Nutrients added in rainfall. For N, also includes the amount of N fixed by legumes. |
| Irrigation |
Nutrients added in irrigation water. |
| Slow Release |
Nutrients released from soil minerals into the plant-available nutrient pool. |
| Net Mineralisation |
Nutrients released from soil organic pools, normally as a result of cultivation. |
| Carried In - Residues |
Nutrients carried in from the previous crop to the current crop in residues. |
| Carried In - Inorganic |
Nutrients carried in from the previous crop to the current crop in inorganic form. |
| Nutrient Outputs |
|
Description |
|
| Product |
Net amount of nutrients removed in produce. |
| Atmospheric Loss |
Loss of N to the atmosphere by ammonia volatilisation and denitrification. |
| Leaching / Runoff |
Nutrients lost to ground (below the rooting zone) or surface water as leaching or as runoff. |
| Residues Removed |
Nutrients removed from the site when residues are burnt or removed as straw etc. |
| Residues Left |
Nutrients in residues left on the site. These are carried over to the next crop. |
| Immobilisation / Absorption |
Net immobilisation of N, P or S in soil organic matter, or absorption of P into slowly available forms in the soil. |
| Change Inorganic Pool |
Change in soil inorganic pools. This is carried over to the next crop. |
Horticultural model
| Nutrient Inputs |
|
Description |
|
|
Fertiliser
|
Nutrients in fertiliser applied |
|
Atmospheric
|
Nutrient added in rainfall. For N, also includes the amount of N fixed by clover in pasture. |
|
Irrigation
|
Nutrients added in irrigation water. |
|
Calcium Nitrate Sprays
|
Nutrients (N, Ca) added in calcium nitrate sprays for apples. |
|
Slow Release
|
Nutrients released from soil minerals into the plant available nutrient pool. |
|
Mineralisation (cultivation)
|
Nutrients released by mineralisation after cultivation during establishment. |
| Nutrient Outputs |
|
Description |
|
| Product |
Net amount of nutrients removed in produce. |
| Atmospheric Loss |
Loss of N to the atmosphere by ammonia volatilisation and denitrification. |
| Leaching / Runoff |
Nutrients lost to waterways as leaching (below the rooting zone) or runoff. |
| Removal of Prunings |
Nutrients removed when prunings are removed. |
| Wind Blown Leaves |
Nutrients lost in wind blown leaves. |
| Gain in Framework |
Nutrients that accumulate in framework as the crop matures. |
| Immobilisation / Absorption |
Net immobilisation of N, P or S in soil organic matter, or absorption of P into slowly available forms in the soil. |
| Change Inorganic Pool |
Change in soil inorganic pools. This is reflected in changes in soil test values. |
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