The Hydrological cycle ..
an open system with stores - in the atmosphere as vapour or gas -only 0.03% of whole system
- on the land where it is stored in rivers, streams,lakes and reservoirs, vegetation, soil, bed rock..usually as a liquid, but can be snow or ice - 80% of world's fresh water.
- The Oceans 98% of total water system isstored in the oceans mainly liquid but some solid icebergs.
with Transfers - evaporation, transpiration, evapotranspiration, condensation, freezing, melting, sublimation (these are movements with a change of state)
- precipitation, surface run off, groundwater control, through flow, infiltration and percolation (without a change in state)
EXAMINATION QUESTIONS
2003
Study figure 3 which shows part of the drainage basin cycle.
(a)
(i) Identify flow C in Figure 3 (1)
(ii) How does percolation differ from infiltration? (2)
(iii)Suggest why rates of percolation vary:
1. from basin to basin...
2.over time .... (4)
(b)
(i) Describe the processes by which rivers erode their channels (3)
(ii) Explain how river erosion influences valley shape (4)
(c)
With reference to a named river, describe and explain its regime. You may use a graph or diagram to help your answer Named river................................... (6)
Jan 2005
Study figure 3 which is from a newspaper article about flooding
(a) With refernce to figure 3:
(i) calculate the Environment Agency's mean spending per person on flood defence and early warning systems in the flod prone areas: (1)
(ii) What did Robin Page suggest was the main cause of the Easter 1998 floods in Bedfordshire, Northhamptonshire and Cambridgeshire? (1)
(iii) suggest how the deepening of channels increases river flow; (3)
(iv) why might building on the flood plain increase the level of water in a river channel? (3)
(b)
(i)Name and outline two processes by which rivers transport their load. (2)
(ii)Explain why the amount and type of load transported by a river may vary over time (4)
(c) With reference to a named river, describe and explain the downstream changes in its discharge Named river ........... (you may draw a diagram to help your answer) (6)
Study figure 4 which shows the relationship between percentage vegetation cover and inflitration rates during a single rainfall event.
(a) With reference to figure 4:
(i) estimate the difference in infiltation rates between bare soil and 37% vegetation cover, 40 minutes after the beginning of rainfall; (1)
(ii) Describe the relationship between infiltration rates and percentage vegetation cover; (2)
(iii) suggest why during the rainfall event;
1. infiltration rates initially decrease; (3)
2. infiltration rates eventually level out (3)
(b)
(i) Name and outline two processes by which rivers erode; (2)
(ii) Explain why rates of erosion vary with river velocity. (3)
(c) With reference to a named river, describe and explain how river processes, such as erosion and deposition, are managed Named river ............... You may use a diagram to help your answer. (6)
2005
Study figure 4 which shows the annual sediment yield of major drainage basins.
(a) using figure 4:
(i) define the term drainage basin (2)
(ii) state the annual sediment yield of the Mississippi drainage basin (1)
(iii) describe the global patterns of annual sediment yield (3)
(iv) suggest one way in which climate may have influenced this pattern (2)
(b)
(i) state how the efficiency (hydraulic radius) of a river channel is calculated (2)
(ii)Describe and explain the relationship between channel efficiency and river velocity (4)
(c)
With reference to a named river, describe and explain the downstream changes in its discharge.
You may use a diagram or graph to help your answer
Named river......................................................... (6)
Useful linka
http://www.georesources.co.uk/indexvf.htm
this has virtual fieldwork case studies for rivers