UAL Crop Nitrogen and Irrigation
Lab
The VegSyst Decision Support System (VegSyst-DSS) as a tool for management of irrigation and N fertilization
The
first version of the VegSyst-DSS software is currently available; the
software can be downloaded using the link on the right. There are also
links for the software manual and for the climate template Excel file.
A video with a demostration of the
software will be
available soon.
The
VegSyst Decision Support System (VegSyst-DSS) has been developed to
calculate
daily N fertilizer and irrigation requirements, and the N concentration
of the
applied nutrient solution applied for fertigated vegetable
crops grown in greenhouses. It can be used for crops grown in soil or substrate. N fertilizer requirements are
based on daily crop N uptake and consider soil mineral N at planting,
and N
mineralized from manure and soil organic matter. Irrigation
requirements are based on estimated evapotranspiration (ETc) and
consider irrigation application efficiency and the salinity of
irrigation
water. ETc can be calculated using the Penman-Monteith equation adapted to greenhouses or the Almeria radiation equation.
VegSyst-DSS has very few
inputs, all of which are readily available to farmers and advisors. Data
inputs are:
- the readily available
climate parameters of daily maximum and minimum air temperature and relative humidity (RH) in the the greenhouse, and solar
radiation
outside the greenhouse
- the amount of soil mineral N in the root zone
at
planting
- details of the most recent manure application
- irrigation layout
- soil characteristics
For the climate data,
an internal
data base of long term average climate data for Almeria can be used;
there is no requirement to enter climatic data. Recommendations based
on long term average climate data are suitable for climates with very
low climatic variation between years such as within greenhouses in
Almeria.
VegSyst DSS provides a detailed science-based plan of daily N and
irrigation requirements that is specific to the characteristics of an
individual
crop.
To fully optimize management, it is suggested that users also use monitoring methods to fine tune N and irrigation management.
VegSyst-DSS
is based on the Veg-Syst crop simulation model which calculates daily
crop
biomass production, critical N uptake and ETc for vegetable crops. The
simulation model is
driven by thermal time and is adaptable to the variations in
climatic conditions thereby providing N and irrigation
recommendations specific to given cropping conditions such as season, time of
planting,
and greenhouse design and covering materials. The VegSyst-DSS assumes
that
crops have no water or nutrient limitations, which is almost always the
case with commercial vegetable production in greenhouses.
The VegSyst-DSS software has been programmed in Visual C# using
Winform visual interface with a ModernUI style; data management is done
through LocalDBv.11 technology for Microsoft SQL Server 2012 Express.
The software calculates
daily N and irrigation requirements for greenhouse-grown tomato,
sweet pepper, cucumber, melon, watermelon, zucchini, and eggplant. It
also calculates the daily N concentration to apply in the applied
nutrient
solution and the average N concentration for four week periods.
For more information about VegSyst-DSS, for help in using it, or for
comments on the material presented please contact Marisa Gallardo,
Departamento de
Agronomia, Universidad de Almería, 04120 Almería, Spain mgallard@ual.es