@article{oai:repo.qst.go.jp:00045942,
 author = {Tagami, Keiko and Uchida, Shigeo and Takeda, Akira and Yamasaki, Shin-ichi and et.al and 田上 恵子 and 内田 滋夫 and 山崎 慎一},
 issue = {5},
 journal = {Soil Science Society of America Journal},
 month = {Sep},
 note = {In this study, a method for estimation of plant unavailable iodine (I) concentrations in soils was proposed. Concentrations of total I and potentially plant available I (i.e. water soluble and organically bound iodine) were measured in 141 agricultural soil samples. For total I measurements, pressed powder pellets were prepared from soil samples and concentrations of I were measured by energy dispersive X-ray fluorescence. Potentially plant available I contents were measured by inductively coupled plasma mass spectrometry after soil samples had been extracted with tetramethyl ammonium hydroxide and their soluble and organically bound I concentrations had been measured (TMAH-extractable I). The results showed a high correlation between the total and TMAH-extractable I concentrations. The geometric means of total and TMAH-extractable I in the paddy field samples were 1.9 and 1.1 mg kg-1-dry, respectively, while those in the upland field soil samples were 5.7 and 4.2 mg kg-1-dry, respectively. For the agricultural soils having less than 5 mg kg-1 total I, it was estimated that the average concentrations of plant unavailable I in paddy fields and upland fields were 0.7+/-0.2 mg kg-1-dry and 0.7+/-0.4 mg kg-1-dry, respectively. The different total I concentrations for fields of the two agricultural uses could be explained by the differences in their redox conditions; I is mobile under reducing conditions so that it was removed from the paddy fields by leaching from the plowed layer or by I volatilization from the soil.},
 pages = {1562--1567},
 title = {Estimation of plant unavailable iodine concentrations in agricultural fields},
 volume = {74},
 year = {2010}
}