The nitrogen and phosphorus cycle

Question 1

what percentage of nitrogen makes up the atmoshpere

Answer 1

78%

Question 2

what is the dominant pathway for nitrogen entering the ecosystem

Answer 2

via nitrogen fixation

Question 3

what 2 ways can nitrogen fixation occur

Answer 3

atmospheric and biological

Question 4

how does atmospheric fixation occur

Answer 4

splitting energy supplied by lighting free nitrogen atoms can then bond to other element s

Question 5

how does biological fixation occur

Answer 5

nitrogen bonds can be broken by certain prokaryotic organisms

Question 6

is nitrate critical for plant growth

Answer 6

yes

Question 7

phosphorus cycle does it take place on local scales

Answer 7

yes

Question 8

the phosphorus cycle

Answer 8

the primary source of new phosphorus is from weathering of p - containing rocks

Question 9

impacts of nitrogen and phoserus fertiliser

Answer 9

impact algae growth upon lakes

Question 10

consequences of eutrophication

Answer 10

increased macroalgal growth
planktonic blooms
oxygen depletion
organically enriched sediments