Construction managers, also called general contractors or project managers, typically do the following: 1  Prepare and negotiate cost estimates, budgets, and work timetables. 2  Select appropriate construction methods and strategies. 3  Interpret and explain contracts and technical information to workers and other professionals.
Denitrification is the process that converts nitrate to nitrogen gas, thus removing bioavailable nitrogen and returning it to the atmosphere. Dinitrogen gas (N2) is the ultimate end product of denitrification, but other intermediate gaseous forms of nitrogen exist (Figure 7).
Nitrogen fixation is the process by which atmospheric nitrogen is converted either by a natural or an industrial means to a form of nitrogen such as ammonia. In nature, most nitrogen is harvested from the atmosphere by microorganisms (see above) to form ammonia, nitrites, and nitrates that can be used by plants.