Nitrogen Cycle Puzzle

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Across
  1. 2. Process where decomposers break down dead organisms into ammonia (NH3)
  2. 4. Agricultural use for nitrogen
  3. 6. This element has the symbol N
  4. 8. The process where plants absorb nitrogen through their roots
  5. 12. What process converts ammonia to nitrate?
  6. 13. Result of excess fertilizer runoff into water
Down
  1. 1. ______ occurs when bacteria convert nitrate back into nitrogen gas
  2. 3. Humans add too much nitrogen to the cycle and disrupt ecosystems by the _______ of fossil fuels
  3. 5. The ocean is an example of a(n)_____ reservoir
  4. 7. Misuse of nitrogen disrupts the cycle and leads to the ______ of lakes and aquifers
  5. 9. Nitrous oxide is a _______ gas
  6. 10. Alternate process to fix nitrogen (not nitrogen fixation, Hint: storms!)
  7. 11. Most organisms cannot use nitrogen in the ____ state