Abstract
This study was conducted to investigate the influence of land-use systems (grassland and cropland) and of long-term no-till cropping systems [bare soil, oat/maize (O/M), pigeon pea+maize (P+M)] on the composition of organic N forms in a subtropical Acrisol. Soil samples collected from the 0- to 2.5-cm layer in the study area (Eldorado do Sul RS, Brazil) were submitted to acid hydrolysis and cross-polarization magic angle spinning (CPMAS) 15N and 13C nuclear magnetic resonance (NMR) spectroscopies. The legume-based cropping system P+M contained the highest contents of non-hydrolysable C and N, hydrolysable C and N, amino acid N and hydrolysed unknown N. The relative proportion of non-hydrolysable N was higher in bare soil (30.0%) and decreased incrementally in other treatments based on the total C and N contents. The amino acid N corresponded to an average of 37.2% of total N, and was not affected by land use and no-till cropping systems. The non-hydrolysable residue contained lower O-alkyl and higher aromatic C concentrations, as revealed by CPMAS 13C NMR spectroscopy, and higher C:N ratio than the bulk soil. No differences in the bulk soil organic matter composition could be detected among treatments, according to CPMAS 13C and 15N NMR spectra. In the non-hydrolysable fraction, grassland showed a lower concentration of aromatic and a higher concentration of alkyl C than other treatments. From CPMAS 15N NMR spectra, it could be concluded that amide N from peptide structures are the main organic N constituent. Amide structures are possibly protected through encapsulation into hydrophobic sites of organic matter and through organomineral interaction.
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References
Baldock JA, Smernik RJ (2002) Chemical composition and bioavailability of thermally altered Pinus resinosa (Red pine) wood. Org Geochem 33:1093–1109
Bayer C, Mielniczuk J, Amado TJC, Martin-Neto L, Fernandes SV (2000) Organic matter storage in a sandy clay loam Acrisol affected by tillage and cropping systems in southern Brazil. Soil Tillage Res 54:101–109
Bremner JM (1965) Organic forms of nitrogen. In: Black CA (ed) Methods of soil analysis. Part II—Chemical and microbiological. ASA, Madison, WI, pp 1238–1255
Burns RG (1982) Enzyme activity in soil: location and a possible role in microbial ecology. Soil Biol Biochem 14:423–427
Camargo FAO, Gianello C, Vidor C (1997) Comparative study of five hydrolytic methods in the determination of soil organic nitrogen compounds. Commun Soil Sci Plant Anal 28:1303–1309
Ceretta CA (1995) Organic nitrogen and humic substances fractionation and characterization of humic acids of soils in no tillage crop systems. Ph.D. thesis, UFRGS, Porto Alegre, Brazil (in Portuguese)
Dieckow J, Mielniczuk J, Knicker H, Bayer C, Dick DP, Kögel-Knabner I (2005) Composition of organic matter in a subtropical Acrisol as influenced by land use, cropping and N fertilisation, assessed by CP/MAS 13C NMR spectroscopy. Eur J Soil Sci (in press, DOI 10.1111/j.1365-2389.2005.00705.x)
FAO (2002) World reference base for soil resources. FAO, Rome
Gonçalves CN, Dalmolin RSD, Dick DP, Knicker H, Klamt E, Kögel-Knabner, I (2003) The effect of 10% HF treatment on the resolution of CPMAS 13C NMR spectra and on the quality of organic matter in Ferralsols. Geoderma 116:373–392
Kelley KR, Stevenson FJ (1996) Organic forms of nitrogen is soil. In: Piccolo A (ed) Humic substances in terrestrial ecosystems. Elsevier, Amsterdam, Netherlands, pp 407–427
Knicker H (2000) Biogenic nitrogen in soils as revealed by solid-state carbon-13 and nitrogen-15 nuclear magnetic resonance spectroscopy. J Environ Qual 29:715–723
Knicker H (2004) Stabilization of N-compounds in soil and organic-matter-rich sediments—what is the difference? Mar Chem 92:167–195
Knicker H, Hatcher P (1997) Survival of protein in an organic-rich sediment: possible protection by encapsulation in organic matter. Naturwissenschaften 84:231–234
Knicker H, Lüdemann H-D (1995) N-15 and C-13 CPMAS and solution NMR studies of N-15 enriched plant material during 600 days of microbial degradadion. Org Geochem 23:329–341
Knicker H, Fründ R, Lüdemann H-D (1993) The chemical nature of nitrogen in soil organic matter. Naturwissenchaften 80:219–221
Knicker H, Saggar S, Bäumler R, McIntosh PD, Kögel-Knabner I (2000a) Soil organic matter transformation induced by Hieracium pilosella L. in tussock grassland of New Zealand. Biol Fert Soils 32:194–201
Knicker H, Schmidt MWI, Kögel-Knabner I (2000b) Nature of organic nitrogen in fine particle size separates of sandy soils of highly industrialized areas as revealed by NMR spectroscopy. Soil Biol Biochem 32:241–252
Kögel-Knabner I (1995) Composition of soil organic matter. In: Nannipieri P, Alef K (eds) Methods in applied soil microbiology and biochemistry. Academic , New York, NY, pp 66–78
Lal R (2000) World cropland soils as source or sink for atmospheric carbon. Adv Agron 71:145–191
Leinweber P, Schulten H-R (1998) Nonhydrolyzable organic nitrogen in soil size separates from long-term agricultural experiments. Soil Sci Soc Am J 62:383–393
Leinweber P, Schulten H-R (2000) Nonhydrolyzable forms of soil organic nitrogen: extractability and composition. J Plant Nutr Soil Sci 163:433–439
Nannipieri P, Sequi P, Fusi P (1996) Humus and enzyme activity. In: Piccolo A (ed) Humic substances in terrestrial ecosystems. Elsevier, Amsterdam, Netherlands, pp 293–328
Nannipieri P, Ascher J, Ceccherini MT, Landi L, Pietramellara G, Renella G (2003) Microbial diversity and soil functions. Eur J Soil Sci 54:655–667
Oades JM, Waters AG, Vassallo AM, Wilson MA, Jones GP (1988) Influence of management on the composition of organic matter in a red-brown earth as shown by 13C nuclear magnetic resonance. Aust J Soil Res 26:289–299
Schulten H-R, Schnitzer M (1998) The chemistry of soil organic nitrogen: a review. Biol Fertil Soils 26:1–15
Stevenson FJ (1994) Humus chemistry: genesis, composition and reactions. Wiley, New York, NY
Zang X, Heemst JDH, Dria KJ, Hatcher PG (2000) Encapsulation of protein in humic acid from a histosol as an explanation for the occurrence of organic nitrogen in soil and sediment. Org Geochem 31:679–695
Acknowledgements
The authors acknowledge CAPES (from Brazil) for the scholarship given to J. Dieckow and DAAD (from Germany) for the mobility of the scientists; P. Müller and S. Roller (TUM), for their helpful technical assistance; CNPq, for the fellowship awarded to J. Mielniczuk, C. Bayer and D.P. Dick; FAPERGS for financially supporting the field experiment; Dr. T. Lovato, Dra. F. Vezzani, Dra. F. Fontana, Dr. L. Debarba and F. Costa for their helpful field collaboration.
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Dieckow, J., Mielniczuk, J., Knicker, H. et al. Organic N forms of a subtropical Acrisol under no-till cropping systems as assessed by acid hydrolysis and solid-state NMR spectroscopy. Biol Fertil Soils 42, 153–158 (2005). https://doi.org/10.1007/s00374-005-0002-4
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DOI: https://doi.org/10.1007/s00374-005-0002-4