Verifiable Water Use Inventory Using ICT …
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of its cover (º)), its management (start and end dates of cover whitening, whitening
dose (kg product/100 L water)) and electrical conductivity of irrigation water
(dS/m).
– Characteristics of the irrigation network: number of pipes per crop line, distance
between emitters (m), nominal flow rate of the emitters (L/h) and sector area (ha).
– Electric tariff. The electricity rate contracted by each farm conditions the management and use of water when the electricity supplier offers different electricity rates
according to the supply voltage and power contracted. Among these tariffs, there
are differences in the number of tariff periods and the number of hours and their
distribution. Because each tariff period will have different prices of power and
energy, for economic or management reasons, the number of hours of irrigation
per day is usually limited. To keep the recommended irrigation time within this
limit, the user must either select the tariff type and irrigation period or manually
enter the maximum number of available irrigation hours from Monday to Friday
and on weekends.
Additionally, the water allowance (m
3 /(ha year)), soil texture, and dates of harvest
end in the last two seasons and production obtained in the last season (t/ha) must be
known.
2.2.2 Climate Data
This module uses climate predictions and historical data to estimate crop water needs.
In this work, the historical climate records were taken from the Agroclimatic Stations
Network of the Regional Government of Andalucía.
The reference evapotranspiration data, ET 0 (mm), recorded at the nearest public
agroclimatic station are used to calculate crop evapotranspiration ETC (mm), equivalent to their water requirements. With this information, an internal database is built
up with the historical water needs of the crop ETC (mm) and its later use to distribute
the available irrigation water for the campaign. For outdoor crops, rainfall records
and ETC data will be used to update the daily soil water balance, which is necessary
to determine the optimal irrigation timing.
To calculate crop irrigation needs, ET 0 predictions are based on Open weather
data (maximum and minimum daily relative humidity information (%)) and on data
obtained from online weather forecast (maximum and minimum temperature (°C),
cloud index (%) and wind speed (km/h)) by web scraping techniques. These data are
used to calculate ET 0 for the next 7 days using the Penman–Monteith equation [3]
for outdoor crops.
Plastic covers modify the outdoor ETo, so to estimate its value in the greenhouse the equation proposed by Fernández et al. [17] based on solar radiation in the
greenhouse was applied (Eq. 1).
ET 0 greenhouse = (0.288 + 0.0019 · DOY) · Rs in for DOY ≤ 220
ET 0 greenhouse = (1.339 − 0.0028 · DOY) · Rs in for DOY > 220
(1)
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of its cover (º)), its management (start and end dates of cover whitening, whitening
dose (kg product/100 L water)) and electrical conductivity of irrigation water
(dS/m).
– Characteristics of the irrigation network: number of pipes per crop line, distance
between emitters (m), nominal flow rate of the emitters (L/h) and sector area (ha).
– Electric tariff. The electricity rate contracted by each farm conditions the management and use of water when the electricity supplier offers different electricity rates
according to the supply voltage and power contracted. Among these tariffs, there
are differences in the number of tariff periods and the number of hours and their
distribution. Because each tariff period will have different prices of power and
energy, for economic or management reasons, the number of hours of irrigation
per day is usually limited. To keep the recommended irrigation time within this
limit, the user must either select the tariff type and irrigation period or manually
enter the maximum number of available irrigation hours from Monday to Friday
and on weekends.
Additionally, the water allowance (m
3 /(ha year)), soil texture, and dates of harvest
end in the last two seasons and production obtained in the last season (t/ha) must be
known.
2.2.2 Climate Data
This module uses climate predictions and historical data to estimate crop water needs.
In this work, the historical climate records were taken from the Agroclimatic Stations
Network of the Regional Government of Andalucía.
The reference evapotranspiration data, ET 0 (mm), recorded at the nearest public
agroclimatic station are used to calculate crop evapotranspiration ETC (mm), equivalent to their water requirements. With this information, an internal database is built
up with the historical water needs of the crop ETC (mm) and its later use to distribute
the available irrigation water for the campaign. For outdoor crops, rainfall records
and ETC data will be used to update the daily soil water balance, which is necessary
to determine the optimal irrigation timing.
To calculate crop irrigation needs, ET 0 predictions are based on Open weather
data (maximum and minimum daily relative humidity information (%)) and on data
obtained from online weather forecast (maximum and minimum temperature (°C),
cloud index (%) and wind speed (km/h)) by web scraping techniques. These data are
used to calculate ET 0 for the next 7 days using the Penman–Monteith equation [3]
for outdoor crops.
Plastic covers modify the outdoor ETo, so to estimate its value in the greenhouse the equation proposed by Fernández et al. [17] based on solar radiation in the
greenhouse was applied (Eq. 1).
ET 0 greenhouse = (0.288 + 0.0019 · DOY) · Rs in for DOY ≤ 220
ET 0 greenhouse = (1.339 − 0.0028 · DOY) · Rs in for DOY > 220
(1)