Measurement of Evapotranspiration

Q. A lysimeter is used to measure

1. infiltration
2. evaporation
3. evapotranspiration
4. radiation

Q.
Consider the following details of crops as given below:

$\begin{array}{cccc}\text{Month}& \text{Monthly temp.}& \text{Monthly percentage}& \text{Usefull}\\ & {\text{Avg}}^{\circ }C& \text{of day time hrs. of year}& \text{rainfall (cm)}\\ \text{November}& 19.0& 7.19& -\\ \text{December}& 16.0& 7.15& 1.2\\ \text{January}& 12.5& 7.30& 0.8\\ \text{February}& 13.0& 7.03& -\end{array}$

If the latitude of the place is ${30}^{\circ }C$, then consumptive use of crop
[Use Blaney-Criddle equation and crop factor, $k=0.75$]

1. 42.4 cm
2. 23.85 cm
3. 31.8 cm
4. 56.67 cm

Q. Consider the following statements:
1. The potential evapotranspiration is the same as the consumptive use for an irrigated crop.
2. Interception losses consist of only evaporation losses.
3. The potential evapotranspiration mainly depends upon characteristics of soil and vegetation.
4. The Lysimeter gives the potential evapotranspiration.

Which of these statements is/are correct ?

1. 2 and 3 only
2. 1 and 2 only
3. 1 and 4 only
4. All of the above

Q. Lysimeter and Tensiometer are used to measure respectively, one of the following groups of quantities:

1. Capillary potential and permeability
2. Evapotranspiration and capillary potential
3. Velocity in channels and vapour pressure
4. Velocity in pipes and pressure head

Q. The mean monthly temperature and monthly percentage of annual day-time (hr) are tabulated below :
$\begin{array}{ccc}\text{Month}& \text{Temperature}{(}^{\circ }C)& \text{Monthly percentage of}\\ & & \text{annual day time 9 hr}\\ \text{Nov}& 16& 7.2\\ \text{Dec}& 11.5& 6.9\\ \text{Jan}& 9.5& 7.0\\ \text{Feb}& 13.5& 8.1\end{array}$


Wheat is grown in the season Nov-Feb, the potential evapotranspiration in this season will be ______ mm.
(Take k = 0.6 and and use Blaney Criddle formula)

1. 244.1

Q. Match List-I (device) with List-II (measured quantity) and select the correct answer using the codes given below :

$\begin{array}{cc}\text{List-I}& \text{List-II}\\ \text{P. Atmometer}& \text{1. Transpiration}\\ \text{Q. Phytometer}& \text{2. Evaporation}\\ \text{R. Lysimeter}& \text{3. Capillary potential}\\ \text{S. Tensiometer}& \text{4. Evapotranspiration}\end{array}$

1. P-2, Q-1, R-4, S-2
2. P-4, Q-1, R-2, S-3
3. P-2, Q-1, R-4, S-3
4. P-1, Q-4, R-2, S-3

Q. In Lysimeter, following observations made for calculation of evapotranspiration are as under:
$W_1$=Original weight of container + Soil+ Plant + Water moisure
$W_2$=Water collected at bottom
$W_3$=Water added
$W_4$=final weight of container content
The evapotranspriation is:

1. $W_1+W_2-W_3-W_4$
2. $W_1-W_2+W_3-W_4$
3. $W_1-W_2-W_3+W_4$
4. None of above

Q. Consider the following data of evapotranspiration from an area near New Delhi in the month of November :
1. Slope of the saturation vapour pressure vs temperature curve at the mean air temperature = 1.00 mm of Hg/ ${}^{\circ }$C.
2. Net radiation in mm of evaporable water/day = 2.
3. Parameter including wind velocity and saturation deficit = 2.5 mm/day.
4. Psychrometric constant = 0.5 mm of mercury/ ${}^{\circ }$C.
Using Penman's formula, the potential evapotranspiration (PET) will be

1. 1.8 mm/day
2. 2.17 mm/day
3. 2.24 mm/day
4. 2.32 mm/day

Q. Match List-I with List-II and select the correct option using the codes given below:
List I:
P. Humidity
Q. Transpiration
R. Precipitation
S. Evapotranspiration

List I:
1. Phytometer
2. Pluviometer
3. Lysimeter
4. Hygrometer

1. $P-2,Q-3,R-4,S-1$
2. $P-4,Q-3,R-2,S-1$
3. $P-4,Q-1,R-2,S-3$
4. $P-2,Q-1,R-4,S-3$