Environmental science 2

4. A widely used group of insecticides. They have been linked with the deaths of bees, especially when they act synergistically with some fungicides.
5. species One of the first species to colonise an area at the start of ecological succession. They are usually well adapted to extreme abiotic factors.
7. A chemical released by an organism that changes the behaviour of other members of the same species, especially to attract a mate.
9. An agricultural system that incorporates the principles of natural ecosystems.
11. The maintenance of a state of equilibrium.
14. A method of reducing soil erosion by creating a grid of raised ridges that cause rainfall to collect, increasing infiltration and reducing
16. The cultivation by turning the soil eg by ploughing.

1. A form of polyculture where two or more different crops are grown in an area at the same.
2. An international organisation which aims to ensure the sustainable exploitation of whales.
3. A qualitative scale that judges the abundance of organisms. Dominant, Abundant, Frequent, Occasional, Rare.
6. A community of species that does not develop to a natural climatic climax community, but is maintained by external influences which prevent this, including human activities such as burning, grazing or ploughing.
8. An organism that thrives in conditions with a high salt concentration.
10. The process of creating habitats that are similar to the conditions present before the natural habitat was changed by human actions.
12. The release of animals from captivity where they are provided with post-release support such as
13. Hedgerows and rows of trees that reduce wind velocity to reduce soil erosion.
15. DNA detected in environmental samples such as water or soil that is used to confirm the presence of the species that produced