Nitrata pollution of groundwater arising from agricultural practices, and some technologies to conrol the polluion

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To clarify the nitrate pollution of groundwater in Miyakonozyo basin, nitrate-N content of some 800 of wall-water was measured for several years. Twelve% of total samples exceeded 10 ppm nitrate-N.Animal waste was considered to be one of main sources of nitrate-N in wall-water in this region.Removal and separation of nitrate anion were carried out using chitosan and chitosan derivatives. Among these, the chitosan derivatives having the secondary amine group showed the high selectivity for nitrate anion over chloride and sulfate anions. The chitosan derivative with the template of nitrate anion exhibited a high adsorption of nitrate anion at pH value around neutrality.Microcapsule containing nitrogen fertilizer as a core-material were prepared using stirene-di-vinylbenzene co-polymerization for various conditions, in which they control the release of the core-materials and have a ability of prevention of groundwater pollution. Shapes and diameters of the pore and the particle sizes were found to be controlled by the preparation conditions. The microcapsule containing 80% of core-materials was found to be prepared in the study.