Humans Have Dramatically Altered the Rate of Nitrogen Fixation into Forms

Multiple Choice

Humans have dramatically altered the rate of nitrogen fixation into forms usable by autotrophs by _____________.

A) selectively removing leguminous plants
B) using antibiotics to reduce the numbers of denitrifying bacteria
C) burning of fossil fuels to meet our energy needs
D) increasing the erosion of farmlands through poor agricultural practices
E) producing synthetic fertilizers and applying them to crops,lawns,and parks