O-LevelGeographyThe natural environment2217/13 · May/June 2014 · Q425 Marks

(a) Study Photograph C (Insert), which shows a river and its valley. [Photograph C] (b) Study Figs 6A and 6B, maps of two deltas. [Figures 6A, 6B]

(a)(i)Give one difference between the vegetation on the flood plain and the vegetation on the valley side.[1]
(a)(ii)Name two processes of river erosion which may take place in the area shown in Photograph C.[2]
(a)(iii)Draw and label a cross section along the line P–Q which is drawn on Photograph C to show: the likely differences in the depth of the channel; a slip off slope; a river cliff.[3]
(a)(iv)Explain how a meander might become an oxbow lake. You may use a diagram or series of diagrams.[4]
(b)(i)Using only evidence from Figs 6A and 6B, compare the deltas of the Niger and Mississippi.[3]
(b)(ii)Explain how a river delta is formed.[5]
(c)For a named area you have studied, describe the problems caused by river flooding. Area studied[7]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Mark scheme

Marking points from the official mark scheme (May/June 2014). The mark or mark type is shown in brackets.

[1] Valley side is forested but flood plain is grassland;
[1] hydraulic action;
[1] abrasion/corrasion;
[1] solution/corrosion;
[1] attrition;
[1] On cross section
[1] 1 mark for asymmetrical profile with P & Q in correct place.
[1] Label with river cliff on correct side. (P).
[1] Label with slip off slope on correct side. (Q).
[1] Ideas such as: faster flow of water on outside of bend;
[1] erosion on outer bank;
[1] neck narrows;
[1] cuts through neck during flooding/cutting through/meander cut off;
[1] ends/former meander sealed by deposition;
NB: can credit information in writing or diagram but no double credit.
[1] Ideas such as: both have distributaries/split into lots of separate channels;
[1] Niger has more distributaries;
[1] Niger is arcuate/fan shaped but Mississippi is birds foot/smoother/less indented in Niger and more irregular for Mississippi/Niger is more triangular;
[1] Niger covers larger area;
[1] Mississippi has lakes but Niger does not;
[1] River/delta in Niger is SW facing and Mississippi river/delta is SE facing;
[1] etc.
NB: Must be comparative.
[1] Ideas such as: large amounts of sediment (brought downstream);
[1] deposition in (lower course);
[1] speed of flow is reduced/river flows slowly;
[1] flocculation occurs due to salt in water;
[1] deposited silt blocks course of river;
[1] splits into distributaries;
[1] deposited materials are not washed away;
[1] lack of currents;
[1] etc.
Level 1 (1–3 marks) Statements including limited detail which describe problems caused by flooding.
Level 2 (4–6 marks) Uses named example. More developed statements which describe problems caused by flooding.
(NB: Max 5 if no named example)
Level 3 (7 marks) Uses named example. Comprehensive and accurate statements, including some place specific reference.
Content Guide: Answers are likely to refer to; Injuries and deaths/drowning; Flooding of farmland; Impacts of food supplies, Disruption to communications, Water borne disease, Economic impacts Damage to housing, cars, possessions; etc.
Place specific reference is likely to consist of: Locational details; Details of amounts of precipitation, Named settlements along river, Time/date etc.
NB: Development must be of the problems;