01785nam a2200193 a 450000100080000000500110000800800410001910000170006024500960007726002690017352010350044265000210147765000100149865000170150865300080152570000190153370000190155270000200157113347382022-04-06       2008    bl uuuu     u00u1 u    #d1 aBYRNE, C. M.  aInsights into the composition of humin from an irish grassland soil.h[electronic resource]  aIn: INTERNATIONAL MEETING OF THE INTERNATIONAL HUMIC SUBSTANCES SOCIETY, 14., 2008, Saint Petersburg. From molecular understanding to innovative applications of humic substances: proceedings... Moscow: Lomonosov Moscow State University, 2008. v. 1, p. 51-54.c2008  aHumin is defined as the fraction of the humic substances (HS) that is insoluble in aqueous solution at any pH value (1). Because of its insolubility it has been the least studied of all the humic fractions (2). Humin typically represents more than 50% of the organic carbon (C) in a soil, and is regarded as the residual organic C that remains after extraction of the HAs and FAs (3). Based on data from solid-state 13C Nuclear Magnetic Resonance (NMR) spectroscopy, it has been concluded that a repeating aliphatic structural unit, possibly attributable to branched and cross-linked algal or microbial lipids, are common to both sediment and soil humin samples (4). Humin becomes enriched in these aliphatic substances because of their selective preservation during organic diagenesis (2). To investigate the composition of humin, The Clonakilty soil, a well drained Brown Podzolic soil in grassland lysimeter studies at the Teagasc Soils Research Centre, Johnstown Castle, Co. Wexford, Ireland and was used in the present study.  ahumic substances  ahumin  aspectroscopy  aNMR1 aNOVOTNY, E. H.1 aHATCHER, P. G.1 aHAYES, M. H. B.