Bacteria that live in the soil and in symbiotic relationships with plants called legumes take nitrogen from the atmosphere and turn it into ammonia (NH3), a form that is usable by plants. This process is called...
A. denitrification
B. ammonium fixation
C. nitrogen fixation
D. combustion
E. glycolosis
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Soil particles are classified into four basic soil classes based on particle size, namely gravel, sand, ______ and clay.
In agricultural soils, soil profile can be divided into ______ , subsurface layer and bottom layer from top to bottom.
The main pathways of soil available nitrogen loss are ______ and denitrification.
Soil water potential is usually ( ).
A. Less than zero
B. Equal to zero
C. Larger than zero
D. Larger than zero or equal to zero