VJC Prelim_H2_GEO_P1_Mark_Scheme

VJC H2 Paper 1 Prelims 1 Section A – Tropical Environments 1 (a) Explain the factors influencing aeolian processes in the arid tropics. [12] Indicative content Responses should consider the wind (e.g. velocity) and surface characteristics (e.g. nature of sediments, vegetation cover) that influence the various aeolian processes (i.e. erosion, transportation and deposition). Higher level responses will have a good coverage of both wind and surface characteristics as well as the different aeolian processes. (b) Discuss the factors influencing mass movement in the tropics. [20] Indicative content Responses can consider how natural and human factors contribute to mass movement through their influence on shear stress and shear strength. Higher level responses may discuss the relative importance of natural factors such as heavy rainfall and tectonic hazards in contributing to mass movements through a consideration of their role as trigger mechanisms. The relative significance of human and natural trigger mechanisms can also be considered. The role of natural and human contributing factors can also be discussed in relation to relevant examples. 2 (a) Explain how channel morphology varies in the tropics. [12] Indicative content Higher level response will be those that are able to show variation explicitly: • Spatial variation across climates: humid (meanders tend to be found at areas with steady discharge e.g. tropical rainforest climate) vs. semi arid or arid (braided channels tend to be form in areas with an unstable flow regime e.g. monsoon/savanna climate) • Spatial variation along length of channel: upper course vs. lower course • E.g. as we move downstream: form ratio gets higher, hydraulic radius gets larger, etc. • Temporal variation: wet vs. dry season (e.g. Auranga River: wet season meander and dry season braided) (b) To what extent do aeolian processes play the most important role in the formation of arid landscapes? [20] Indicative content

2 Responses can discuss the role of aeolian and fluvial processes in the formation of various arid landscapes such as yardangs, dunes, loess and rills and gullies. Higher level responses will explicitly weigh the relative importance of aeolian and fluvial processes in the formation of the various arid landscapes. There is also a strong awareness of the conditions in the arid tropics that impacts the relative significance of aeolian and fluvial processes (e.g. the lack of precipitation; the rare but intense precipitation; the lack of vegetation cover). Strongest responses may even consider how the relative importance of aeolian and fluvial processes may have changed over time (e.g. as climates have changed).

3 Section B – Development, Economy and Environment 3 (a) Explain the relevance of the arguments made by Malthus and Harvey to resource scarcity in countries at different levels of developm