Agricultural Systems
- To obtain food humans use and modify the ecosystems through farming
- There are four groupings commonly used to categorise farming:
- Arable and pastoral
- Commercial and subsistence
- Extensive and intensive
- Nomadic and sedentary
- A farm that has both livestock and grows crops is a mixed farm
Factors influencing the type of agriculture
Physical Factors | Human Factors |
Temperature - all crops have a minimum temperature below which they will not grow or will not produce a good yield - wheat grows best between 21-24oC | Tradition - many farms simply grow the crops or raise the livestock that have been on the farm for generations |
Growing season - the length of the growing season affects the type of crop grown - barley needs about 90 days from sowing to harvest whereas rice takes about 120 days | Subsidies - farmers may change crop or livestock dependent on the money available from the government |
Precipitation - both the average annual rainfall and the distribution over the year affect the types of crops grown | Transport - the cost of transporting the product may affect what is produced. Livestock transport is more expensive than grain transport |
Relief and slope aspect - the altitude of land affects temperature and the steepness affects the suitability for crops. in local areas different crops may be grown on south facing slopes which get more sunshine and are warmer | Farm size - due to economies of scale larger farms are able to afford more in terms of feed, fertiliser and machinery, this may affect what is produced |
Soil type and fertility - in areas with thin, infertile soils grazing is likely to dominate as crops need deeper, more fertile soil | Market demand - the changing demand for produce. There has been an increase in demand for meat such as buffalo and ostrich which may affect the choice of what is produced |
Drainage - for most crops to grow the land needs to be well drained so that roots do not get waterlogged | Capital - the amount of money a farmer has to invest will affect the machines and artificial inputs (irrigation, pesticides, fertilisers) they can afford |
Farming systems
- All farms are systems, they have inputs, processes and outputs
A Farming System
Impacts of farming systems
- All farming systems impact the ecosystem in which they are located
- Some have more impact than others, such as:
- Monocultures which reduce diversity because the animals have no access to a wide range of foods
- When nutrient cycling is often dependent on fertilisers added to the soil, this may be natural (manure) or artificial fertilisers
- When the ecosystem is modified with inputs of seed, fertiliser, pesticides, herbicides and the use of machines
- Where food webs are reduced
- Reducing the amount of biomass
Exam Tip
Remember farms do fit into more than one category. For example, a sheep farm in Cumbria. UK would be categorised as arable, commercial, extensive and sedentary.
Worked example
Insert the following words into the table below to show examples of inputs, processes and outputs of a mixed farm.
[3]
Choose from the words below
milk wheat harvesting
ploughing water pesticides
Inputs | Processes | Outputs |
- Answer:
Inputs | Processes | Outputs |
water | harvesting | wheat |
pesticides | ploughing | milk |