Which of the following is an example of one stage in ecological succession? A. A tree falls over in a forest.
B. Weeds grow in a garden.
C. Fish swim in a pond.
D. A bird lays eggs in a nest.

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.

the answer

b.) bowling ball