Figure 54.9
-Which of the following is not a source of human-fixed nitrogen?
A)industrially produced fertilizers
B)cultivation of soybeans
C)combustion of fossil fuels
D)irrigation agriculture

Question

Figure 54.9 
-Which of the following is not a source of human-fixed nitrogen?
A)industrially produced fertilizers 
B)cultivation of soybeans 
C)combustion of fossil fuels 
D)irrigation agriculture

Quizplus · Accepted Answer

Irrigation agriculture is not a source of human-fixed nitrogen; it involves the application of water to crops, not the fixation of nitrogen.

Figure 54.9 -Which of the Following Is Not a Source of Human-Fixed