Micronutrient Cation Complexes in Soil Solution: IV. The Chemical State of Manganese in Soil Solution

Abstract

Soil solutions from several areas of the US were analyzed by atomic absorption for total Mn and by resin exchange for percent Mn complexed. Values for the latter (84%–99%) in soil solution from the A horizon were intermediate to those previously reported for Zn and Cu. Soil solution from a New York forest soil at pH 7 contained 13 ppm Mn, of which 93% was complexed. Spectrophotometric and polarographic methods were developed to determine the oxidation state of Mn in this soil solution. Both methods indicated the Mn in solution was present in the +2 oxidation state. The presence of such large concentrations of Mn2+ in a soil solution of a neutral soil was still less than that predicted from measured values of the Eh of the soil solution and the Mn2+/MnO2 half‐cell potential. Soil microorganisms oxidized and precipitated Mn2+, presumably as MnO2, but the presence of the neutral soil solution that contained 13 ppm Mn partially inhibited this precipitation.

Ecology of Mycorrhizae and Mycorrhizal Fungi

“…Acid soils contain much soluble AI, Mn, and Fe, and in neutral soils Mn and Fe can be released in large quantities when reducing conditions prevail after waterlogging (Ponnamperuma, 1972). Geering et al (1969) found that soil solution Mn concentrations in a silt loam varied 100-fold during one year as a result of seasonal influences. Many soils are grossly polluted with heavy metals as a result of man's activities of mining and smelting.…”

Chemistry of metal–humic complexes contained in Megalopolis lignite and potential application in modern organomineral fertilization

“…The complexation properties of Na, Cu, Zn, and Mn (almost equally retained) are of particular importance for employing humic substances in the fertilizer production lines; the Cu-and Zn-humic complexes proved valuable, significantly increasing the plant uptake and the shoot and root dry weight (Garcia-Mina et al, 2004). Moreover, Hodgson et al (1965), Hodgson (1966) and Geering et al (1969) reported that in limy, alkaline soil solutions most of the Cu, Zn, and Mn were present in the form of organic matter complexes. In addition, Cu and Zn demonstrate complexation activity varying with the molecular mass of the humic substances studied (Nifant'eva et al, 2001).…”

Incorporation of humic-derived active molecules into compound NPK granulated fertilizers: main technical difficulties and potential solutions

“…This chemical feature of HS improves physical soil properties favoring the formation of stable clay-humic aggregates through cation bridges, and soil fertility increasing mineral nutrient (P, Fe, Mn or Zn) availability for plants grown in alkaline and calcareous soils [15]. In fact, several studies have reported that a very significant fraction of Cu, Zn, Fe and Mn in soil solution from limy, alkaline soils was present in the form of complexes with DOM [16][17][18].…”