What you’ll learn3 learning objectivesChoose one objective for a focused lesson, or study the complete topic.20.1.1Humans have increased food production• Describe how humans have increased food production, limited to: (a) agricultural machinery to use larger areas of land and improve efficiency (b) chemical fertilisers to improve yields (c) insecticides to improve quality and yield (d) herbicides to reduce competition with weeds (e) selective breeding to improve production by crop plants and livestockSyllabus objective20.1.2Advantages and disadvantages• Describe the advantages and disadvantages of large-scale monocultures of crop plantsSyllabus objective20.1.3Advantages and disadvantages• Describe the advantages and disadvantages of intensive livestock productionSyllabus objective