3. THE RELATIONSHIP BETWEEN AGRICULTURE AND ECOSYSTEMS

There is a complex relationship between the living and no-living components of ecosystems dependent on climate and weather for agricultural production. If we draw a mind-map of how climate and weather directly and indirectly influence agricultural production, it may look something like this.

Fig. 10 Direct and indirect effects of climate and weather on agricultural production.

Source: QDPI

Exercise
Label the following on the picture below:
· Solar energy
· Water cycle (Precipitation, Run-off, Infiltration, Streamflow)
· Food chain (Producers - consumers [herbivores, carnivores])
· Photosynthesis (O₂ utilised in respiration releasing CO₂; CO₂ utilised in photosynthesis releasing O₂)
· Nutrient cycling (including water and nutrient uptake in plants, dead animals and wastes- decomposers-organic material converted to organic compounds)

Fig. 11 An agricultural Ecosystem

Source: NSW Agriculture

This picture shows how agriculture is an integral part of ecosystems, and cannot be seen in isolation from ecosystems. If we dig a little deeper and look at how the same climate and weather impacts differently on different soil types, it becomes even more complex (see Fig. 12).

Optional extension exercise.
Discuss and draw up posters of :
· energy flows in a natural system vs a farm system
· the mineral cycle (eg. Carbon, Nitrogen)
· the water cycle
· a farm cycle for your local area
As a project, discuss how important the water and nutrient cycle is in agriculture.
Questions to answer: How does climate and weather influence the farm cycle? Describe how agricultural systems need to work with ecosystems, not against ecosystems?
View Video "Farming a Sunburnt Country" and discuss its main messages.

Fig. 12. Influence of soil type on other variables. Because there are currently a number of different soil types on a farm, each soil type will react specifically to the weather and climate acting upon it and usually behaving differently with each soil type there is. This will then have an influence on the types of animals and plants that are part of that agricultural system on that property as a function of the soils, weather and climate.

Source: QDPI