TY - JOUR
T1 - Effect of liming on organically complexed aluminum of nonallophanic Andosols from northeastern Japan
AU - Takahashi, Tadashi
AU - Ikeda, Yuya
AU - Fujita, Kenshi
AU - Nanzyo, Masami
N1 - Funding Information:
This work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (No. 11460030) and by a Grant for Environmental Research from the Sumitomo Foundation (No. 013018).
PY - 2006/1
Y1 - 2006/1
N2 - Aluminum-humus complexes are believed to be highly stable under natural conditions in nonallophanic Andosols. However, it has been shown that the aluminum complexed with humus is easily released by acidic buffer solutions and possibly controls the aluminum solubility of these soils. Thus, it is highly probable that Al-humus complexes are easily influenced by rather simple chemical treatments. We examined the effects of liming (CaCO3 treatment) on Al-humus complexes of A and B horizons from Andosols. It was observed that liming reduced the Al release rates from soil samples with pH 3.5 acetate buffer solution and the amounts of the KCl-extractable Al, suggesting the formation of precipitation from easily exchangeable Al. A much larger decrease with liming was also obtained for 0.1 M sodium pyrophosphate-extractable Al (decrease rates of 7-52%) and 0.5 M CuCl2-extractable Al (decrease rates of 9-43%). These results strongly indicate that liming reduces significant amounts of organically complexed Al as well as the exchangeable Al. The increase in the cation exchange capacity of soils at pH 7 after liming further suggested that the carboxyl group of humus complexed with Al was partly liberated from the Al complexation and became to develop negative charges.
AB - Aluminum-humus complexes are believed to be highly stable under natural conditions in nonallophanic Andosols. However, it has been shown that the aluminum complexed with humus is easily released by acidic buffer solutions and possibly controls the aluminum solubility of these soils. Thus, it is highly probable that Al-humus complexes are easily influenced by rather simple chemical treatments. We examined the effects of liming (CaCO3 treatment) on Al-humus complexes of A and B horizons from Andosols. It was observed that liming reduced the Al release rates from soil samples with pH 3.5 acetate buffer solution and the amounts of the KCl-extractable Al, suggesting the formation of precipitation from easily exchangeable Al. A much larger decrease with liming was also obtained for 0.1 M sodium pyrophosphate-extractable Al (decrease rates of 7-52%) and 0.5 M CuCl2-extractable Al (decrease rates of 9-43%). These results strongly indicate that liming reduces significant amounts of organically complexed Al as well as the exchangeable Al. The increase in the cation exchange capacity of soils at pH 7 after liming further suggested that the carboxyl group of humus complexed with Al was partly liberated from the Al complexation and became to develop negative charges.
KW - Aluminum-humus complexes
KW - Copper chloride-extractable aluminum
KW - Liming
KW - Nonallophanic Andosols
KW - Pyrophosphate-extractable aluminum
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U2 - 10.1016/j.geoderma.2005.01.006
DO - 10.1016/j.geoderma.2005.01.006
M3 - Article
AN - SCOPUS:29344463390
SN - 0016-7061
VL - 130
SP - 26
EP - 34
JO - Geoderma
JF - Geoderma
IS - 1-2
ER -