Summary
Crop blocks require two years of crop data to be entered. Activities such as cultivation, sowing, harvesting and defoliation are entered on a monthly basis. The nutrient and GHG results are generated for the final year (reporting year), while the previous years activities are used to set up the nitrogen soil pool for the start of the reporting year. In this way OverseerFM is able to consider previous activities in the analysis of a "typical" years nutrient transfers.
The following diagram depicts what parts of the model the crop information entered in OverseerFM impacts. For a full interactive view of the scientific model in its entirety please click here
Impact
Crop type defines characteristics that drive crop cover, growth, metabolic energy if fed to animals and nutrient uptake. Cover affects surface runoff (hydrology), while growth and uptake affect nutrients being fed to animals as crops and the amount of nitrogen in the soil pool.
Details
In the past crop blocks were often also broken down by soil and irrigation, with OverseerFM the number of blocks can be reduced.
Each crop in Overseer defines a set of characteristics that influence how nutrients build up and are used in the soil. So, crops with similar characteristics will provide similar results. Please refer to Crop types in OverseerFM.
Crops are entered over a two-year period. The model moves through each month estimating the nitrogen pools in the soil. The previous year is used to set up the pools for the reporting year.
Over time residue decomposition occurs, releasing nutrients from the soil. The amount released is affected by temperature, the soils water capacity and the cultivation practice. Using conventional tillage has a greater effect on the nutrients released.