About the book
Nitrogen is an essential major elements in all organisms, as the components of proteins, amino acids, nucleic acids, and many indispensable metabolites. Nitrogen is the most important nutrient elements for agriculture, because the availability of nitrogen from soil is generally not enough to support the yields and quality of crops.
In addition the nitrogen stored in soil is decreased by repeated cultivation, because the harvested parts of crop is taken out from the fields. To keep the soil fertility, crop rotation and application of organic matters have been practiced. After chemical nitrogen fertilizers have been produced by the industrial nitrogen fixation, farmers can use the chemical nitrogen fertilizers for agriculture. As a result, the productivity of crops increased several folds during 20th century to feed the increasing world population. On the other hand, the excess or inappropriate use of nitrogen fertilizers caused environmental problems such as nitrate leaching and contamination in ground water and rivers, emission of global warming gas N2O.
In this book, recent progress will be introduced on the N in agriculture, especially N utilization and efficient use in crops, dynamics of soil N in agricultural fields and its role on agriculture, ecology of nitrogen in agriculture, and nitrogen fertilizers in agriculture, in order to improve nitrogen use efficiency and reduce the ecological problems for sustainable agriculture.