摘要
ＳｔｕｄｙｏｎＷａｔｅｒ－ＳｏｌｕｂｌｅＯｒｇａｎｉｃＲｅｄｕｃｉｎｇＳｕｂｓｔａｎｃｅｓ：Ⅲ．ＥｌｅｃｔｒｏｃｈｅｍｉｃａｌＰｒｏｐｅｒｔｉｅｓｏｆＤｅｃｏｍｐｏｓｉｔｉｏｎＰｒｏｄｕｃｔｓｏｆＲｉｃｅＳｔｒａｗａｎｄＴｈｅｉｒＩｎｔｅｒａｃｔｉｏ...
Some electrochemical properties,such as PH,Eh,and voltammetric behavior,of the decomposition products of rice straw and the in eractions of these products with soils were studied.The PH,Eh,and amounts of organic reducing substances changed markedly during the 60-day anaerobic decomposition.pH decreased sharply to pH 5 on the tenth day and then increased gradually to 7 on the 45th day.The amouats of organic reducing substances increased almost synchronously with the fall of redox potential during the first 15 days.The differential pulse voltammetric(dpv) behavior changed not only in the peak current but also in the peak potential.The fractions with apparent molecular weights lower than 200 dations appeared to be active in dpv behavior.The electric charge of organic reducing substances was closely related to the decomposition stage.The 6th day of incubation was the crucial time before and after which the major part of the components was negatively charged and positively charged, respectively.The group with a low apparent molecular weight and a negative charge was the main components responsible for the lower anodic peak potentials.They were oxidized first during the interactions of the organic reducing substances with soils.
