B6.2.2 Flashcards
What are problems with overfishing and why is fish needed
Fish are valuable sources of protein. However, overfishing has lead to reduction in the populations of some fish species -> can’t regenerate -> can’t be used in the future.
Sustainable food production definition
Producing food in ways that can be continued indefinitely
How have international organisation reduced overfishing 1
They have introduced fishing quotas. These provide limits on the number and types of fish that can be caught in an area.
How have international organisation reduced overfishing 2
Regulations on size of fishing nets - bigger means only full sized fish are caught. Young fish can escape.
How can fish farming reduce overfishing
Fish can be farmed. They are bred and reared in large cages in the seas or rivers. Protects fish from predators, makes them easier to catch and allows wild populations to recover.
Disadvantage of fish farming
Increased risk of disease spreading as they are kept so close together.
What are sustainable of farming for crops
Reduce the use of fertilisers and pesticides.
Instead of using artificial artificial fertilisers what is used
They replace nutrients by spreading manure
What is crop rotation
They take different nutrients from the soil. Planting different crops at each year - gives soil the chance to recover, maximises plant growth. Prevents buildup of a particular crop pest.
How do intensive farmers deal with crop pests
By spraying pesticides
How do sustainable farmers deal with crop pests 1
By using biological control, predators are bred in large numbers and released onto crops where they cut the pest’s numbers.
How do sustainable farmers deal with crop pests 2
Through gene technology scientists are developing crop variations that are more resistant to pests and disease.
What is hydroponics
Plants are grown in water containing dissolved minerals.
Hydroponic plants are stacked above each other so more plants can grow in the same space.
