AG843_PAST_EXAM_PAPERS
The following are selected questions taken from previous exam papers.
1999 BSC Assess the advantages and drawbacks of overhead irrigation methods and highlight how the specific characteristics of these irrigation systems affect irrigation efficiencies.
BSc and MSc 1999 Define reference crop evapotranspiration and state what climatic data are required for its calculation. Explain how to use such calculated values to estimate the water requirements of an annual crop, discussing any assumptions you make.
BSc and MSc 1999 Discuss the reasons for the following observations:
a)soils differ in their water holding capacity (15% of marks)
b)Puddles form at lower rainfall intensities on some soils compared to others (15%)
c)Puddles often do not from immediately after the onset fo rain, but sometimes form only after it has been raining for some time. (15%)
d)Direct evaporation from the bare surface of very sandy soils is usually less that from the surface of bare clay soils(15%)
e)Crop species differ in the amount of water that can be extracted from a soil profile that is initially at field capacity before the soil water stress is sufficiently severe to affect crop growht. (40%)
MSc 1999 Assess the advantages and drawbacks of overhead irrigation methods and highlight how the specific characteristics of these irrigation systems affect irrigation efficiencies.
MSc 1999 Describe how water harvesting and water conservation measures can be used to supplement rainfed crop production by smallholder farmers.
2000 BSc Compare and contrast between subsurface and surface irrigation in terms of their procedure, advantages and disadvantages.
2000MSc Hort. Assess the advantages and drawbacks of surface irrigation methods and highlight how the specific characterisitcs of these irrigation systems affect irrigation efficiencies.
MSc 2000:
Q. 7
a)What is meant by the term 'soil water deficit'?
b)Explain why it is that crops can show symptoms of water stress when the soil water deficit is very much less than the amount of water plant-available water stored within the root zone.
c)How is the limiting soil water deficit affected by characteristics of the soil, crop and weather?
MSc 2000: State the physical principles which form the basis of the Penman-Monteith equation for estimating evapotranspiratin from a crop.
MSc 2000: Outline how to use reference crop evapotranspiration and crop coefficients to estimate the water requirements of an annual crop. Discuss the relationships between crop coefficients and the canopy and aerodynamic resistances in the Penman-Monteith equation. (NOTE: a full derivation of the equation is not required.)