What will be the WUE (kg/ha/mm), if wheat crop used 40 cm of water during whole period and yielded 4.0 t/ha of grains
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Always ensure your units are correct before starting calculations:
1 ton = 1000 kg.
1 cm = 10 mm.
This helps prevent errors when working with decimal places.
Step 1: Understanding the Concept:
Water Use Efficiency (WUE) is a measure of a crop's ability to convert water into economic yield.
It is defined as the ratio of crop yield to the total amount of water used by the crop (evapotranspiration) over its growing period. Key Formula or Approach:
The formula for Water Use Efficiency (WUE, in kg/ha/mm) is:
\[
WUE = \frac{\text{Economic Yield } (Y, \text{ in kg/ha})}{\text{Water Consumed } (W, \text{ in mm})}
\] Step 2: Detailed Explanation:
Let us convert the given values into the standard units required by the formula:
1.Convert Yield (\( Y \)) from tons to kilograms:
\[
Y = 4.0 \text{ t/ha} = 4.0 \times 1000 \text{ kg} = 4000 \text{ kg/ha}
\]
2.Convert Water Used (\( W \)) from centimeters to millimeters:
\[
W = 40 \text{ cm} = 40 \times 10 \text{ mm} = 400 \text{ mm}
\]
3.Calculate WUE:
\[
WUE = \frac{4000 \text{ kg/ha}}{400 \text{ mm}} = 10 \text{ kg/ha/mm}
\]
This means the wheat crop produced 10 kg of grain per hectare for every millimeter of water consumed. Step 2: Final Answer:
The water use efficiency of the wheat crop is 10 kg/ha/mm.
