(a) (i) Explain the term surface drainage. (ii)List three disadvantages of surface drainage (b)(i) Define irrigation. (ii) State two aims of irrigation. (iii) List five problems associated with irrigation.
Explanation
(a)(i) Surface drainage is a process whereby excess water can be removed from farm land using constructed open ditches to avoid water logging (ii) Disadvantages of surface drainage include (1) Open drains occupy good land that would have been used for planting (2) Open ditches are expensive to maintain. (3) Open ditches hinder the passage of machines like tractors. (4) Open ditches are prone to gully erosion or silting up. (5) Cost of constructing drains or ditches are high. (6) Ditches provide hiding or breeding place to some pests. (b)(i) Irrigation is the artificial application of water to the soil to supplement insufficient rainfall (ii) Aims of irrigation are(1) add water to the soil in order to supply moisture for plant growth. (2) ensure survival of crops during droughts (3) cool the soil and atmosphere thereby making the environment more favourable for plant growth (4) make early planting possible. (iii) Problems associated order to with irrigation are: (1) high cost of equipment. (2) it results in erosion and leaching. (3) salt problems/salinity (4) water availability. (5) transmission of diseases. (6) build up and spread of Pests (7) high cost of maintenance of irrigation facilities. (8) aids weed dispersal (9) It hinders the movement of machines.