SUNDIAL: The Research Tool

The SUNDIAL model incorporates current scientific knowledge on the individual processes of nitrogen turnover, and integrates these processes to simulate what happens in the whole soil. It has a modular structure, each module representing one of the major nitrogen turnover processes. Inputs of nitrogen to the soil include those from fertiliser, manures, crop residues and from the atmosphere. Nitrogen is transformed within the soil by mineralisation and immobilisation of organic matter and nitrification of ammonium, and removed from the soil by crop uptake, nitrate leaching and gaseous losses. SUNDIAL requires simple field specific information as input data: the soil texture class, previous cropping history, the current crop type together with its sowing and harvest dates. The crops currently supported are annual arable crops and some field-grown horticultural crops commonly grown in the UK. It runs on a weekly time-step, using the weekly rainfall, evapotranspiration and mean weekly temperature as meteorological inputs. See Model Description for a more detailed description.

SUNDIAL the Research Tool can be used to follow the fate of any fertiliser or organic manure applied during one or more growing seasons, to predict the amount of nitrate leached from the soil, to look at sources of that nitrate and to explore practical strategies for reducing nitrate leaching. SUNDIAL can be run for a number of years so that the cycling of nitrogen can be examined through various crop rotations (modelling whole farm systems). SUNDIAL the Research Tool has been distributed to over 250 scientists world wide.

The development of SUNDIAL the Research Tool was primarily funded by the Home-Grown Cereals Authority (HGCA).

Back to Sundial home page