1. 3.5 Food Resources Compare and contrast the efficiency of terrestrial and aquatic food production systems.
Key ideas: efficiency, trophic levels, terrestrial farming, aquatic farming.
Assessment statement: 3.5.2

2. Define terrestrial and aquatic food production
Terrestrial farming is that which takes place on land. It can be in the form of arable (crops) or pastoral (animals), commercial (products sold for profit at market) or subsistence (to eat), intensive (small-scale and high input) or extensive (large scale and low input), and nomadic (farmers move around seasonally) or sedentary (farmers stay in one place).
Aquatic farming is the production of food stuffs from water sources. This can be either flora or fauna from marine or riparian ecosystems.

3. Terrestrial Farming Energy Efficiency
Kilocalories of fossil fuel input per kilocalorie of protein output
Food Type
Feed lot beef
20-78
Pigs 35
Broiler chicken 22
What is the difference between these two?
Rangeland Beef 10
Sheep 10
Vegetables
2-4
Terrestrial Farming Energy Efficiency

4. Kilocalories of fossil fuel input per kilocalorie of protein output
Seafood type
Marine Fisheries
Shrimp
3-98
Salmon
18-52 20
Cod
Ocean Aquaculture
Salmon cage
culture 50
Salmon ranching
7-12
Aquatic Farming Energy Efficiency
Seaweed 1

5. Find the food-chain or food-web for these:

6. Remember the second law of thermodynamics!
10% rule…

8. Comparing Food Production
Terrestrial
Food is harvested from low trophic levels.
More efficient fixing of solar energy by photosynthesis.
Aquatic
Food is harvested from higher trophic levels mostly because of human taste.
Energy conversions are more efficient along the food chain.

9.
Listen to / watch this link for a more in-depth look at the similarities and differences between these two methods…

10. What other things could we compare / contrast?
Inputs – What fertilisers, pesticides, fuels, labour, breeding stock are needed for both systems? System characteristics – How sustainable are these systems? Environment – Do these strategies lead to pollution, over-extraction, reduction in biodiversity, habitat destruction.
Find a NAMED EXAMPLE for one of each of the above headings for both an AQUATIC and a TERRESTRAIL SYSTEM.