Question 1 Report
Fig. 1 shows an aerial-style sketch of irrigated fields beside the Colorado River in a hot desert area. A farmer has used water from a canal for cotton production. Over several years, white salt has appeared at the edge of some fields, where drainage is poor. The farmer is considering a new drainage ditch.
(a) Which process moves water upwards through soil pores: capillary action, mass movement or saltation? [1]
(b) Outline how irrigation can lead to soil salinisation in this landscape. [2]
(c) Draw a drainage ditch on Fig. 1 in a position that could remove excess water from the fields. [2]
(a) Capillary action [1] (b) Irrigation water contains dissolved salts [1]; water evaporates/raises through soil and leaves salts behind [1]. (c) Ditch drawn from low/wet field edge towards the existing lower drainage line/away from fields [2]
Everything you need to excel in your exams