Qn: evaluate how technological advances, other than irrigation, have helped to increase yield of food crops in less developed countries.
by Lynette Chan
1. demand
1.1. 1. name the other technological factors
1.2. 2.describe the factors and link to how they would increase yield of food crops in LDCS
2. Factors
2.1. 1.use of chemicals
2.2. 2.high-yielding varieties
3. How did they help to increase yield of food crops 1. use of chemicals - fertilisers, pesticides, herbicides 2. high-yielding varieties- eg. wonder rice, shorter growing period, farmers enjoy higher outputs per unit area in their fields. eg. china's rice output more than doubled from 1961 -1992