environmental systems

12345678910111213141516171819202122232425
Across
  1. 4. a substance that is toxic to plants, used to destroy unwanted vegetation.
  2. 7. the action or process of adapting or being adapted.
  3. 12. prevention of wasteful use of a resource.
  4. 13. the process by which fertile land becomes desert, typically as a result of drought, deforestation, or inappropriate agriculture.
  5. 14. is waste that is dangerous or potentially harmful to our health or the environment.
  6. 15. An invasive species is a species that is not native to a specific location, and that has a tendency to spread to a degree believed to cause damage to the environment, human economy or human health.
  7. 16. A species that normally lives and thrives in a particular ecosystem.
  8. 17. a term describing the relational position of a species or population in an ecosystem. ... According to the competitive exclusion principle, no two species can occupy the same niche in the same environment for a long time.
  9. 18. the weather conditions prevailing in an area in general or over a long period.
  10. 20. the variety of life in the world or in a particular habitat or ecosystem.
  11. 22. an area or ridge of land that separates waters flowing to different rivers, basins, or seas.
  12. 23. a biological community of interacting organisms and their physical environment.
  13. 24. a large natural or artificial lake used as a source of water supply.
  14. 25. involves the management and modification of natural environment or wilderness into built environment such as settlements and semi-natural habitats such as arable fields, pastures, and managed woods.
Down
  1. 1. the action of preserving something.
  2. 2. physical rather than biological; not derived from living organisms.
  3. 3. all the waters on the earth's surface, such as lakes and seas, and sometimes including water over the earth's surface, such as clouds.
  4. 5. a tool that allows the user to determine the identity of items in the natural world, such as trees, wildflowers, mammals, reptiles, rocks, and fish.
  5. 6. refers to the range of habitats present in a region.
  6. 8. avoidance of the depletion of natural resources in order to maintain an ecological balance.
  7. 9. a substance used for destroying insects or other organisms harmful to cultivated plants or to animals.
  8. 10. the dependence of two or more people or things on each other.
  9. 11. a large naturally occurring community of flora and fauna occupying a major habitat, e.g. forest or tundra.
  10. 19. relating to or resulting from living things, especially in their ecological relations.
  11. 21. a substance used for killing insects.