Some microbes produce compounds that lower crop production. Increasing the symbiotic fixation rate 127.
Humus has a very high specific surface area and possesses a net positive electrical charge.
False, made true by changing 'positive' to 'negative' d. False, made true by making both the changes 131. Use the following answers for the next 3 questions. Heterotrophic organisms use light as an energy source to produce an energy rich carbon source for autotrophs. N ratio of humus is independent of the organic matter content 138.