Dynamax Dynamet 5, Руководство пользователя

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Dynamet 5
33
To this amount we must add the losses by soil evaporation, which must be estimated from
previous data, if available. Assuming one tree occupies a 10 m2 area, and if the transpiration is
80% of ETP, then the suggested irrigation is 333 kg or 86 gallons (per 10 m2), i.e. 266 kg / 80
%. That would translate to an irrigation of 33.3 mm to replenish the water used over four days.
Many variations on this theme can be formulated for a specific application.
One caution should be stated. The ETP estimate is only a quantitative measure of the
evaporative demand, and is not intended to be an estimate of the actual water use by the crop
or the trees, even if they are well watered. Therefore, the two variables, ETP and stem or trunk
flow rate, are expressed as mm per hour and kg/plant/hour, respectively, even though the water
use by vegetation is often also expressed as mm per hour or per day. The relation between
daily ETP and daily stem or trunk flow rate is not even necessarily linear, that is, the quotient
(stem or trunk flow rate). ETP may not be constant over the entire range of weather conditions
or the development period of a crop.