EFFECT OF FREEZING-THAWING ON THE ACCUMULATION OF NITRITE IN SOIL-WATER SYSTEM
冻融对土－水系统中亚硝酸盐积累的影响

Effects of temperature and freezing-thawing on denitrifcation and accumulation of ni-trite in different soil-water systems were investigated.Incubation experimental results indi-cated that the accumulation of nitrite under low temperature,especially freezing-thawingconditions,is due to enhancing involvement of organic matter in mineralization by freezing-thawing events,which provided the available organic carbon compounds for denitrifyingbacteria,The results have been used to interpret Keshan disease environmental geochemicalpathonecy. Acute Keshan disease is usually prevalent in winter-spring seasons,related tothe accumulation of nitrite in large amounts in the water body under freezing-thawing condi-tions.