Labile soil organic matter pools under a mixed grass/lucerne pasture and adjacent native bush in Western Australia
A. J. Macdonald A E , D. V. Murphy B , N. Mahieu C and I. R. P. Fillery DA Soil Science Department, Rothamsted Research, Harpenden, Herts AL5 2JQ, UK.
B School of Earth and Geographical Sciences, Faculty of Natural and Agricultural Sciences, The University of Western Australia, Crawley, WA 6009, Australia.
C Queen Mary, University of London, London E1 4NS, UK.
D Commonwealth Scientific Industrial Research Organisation, PO Box Wembley, WA 6193, Australia.
E Corresponding author. Email: andy.macdonald@bbsrc.ac.uk
Australian Journal of Soil Research 45(5) 333-343 https://doi.org/10.1071/SR06133
Submitted: 27 August 2006 Accepted: 14 June 2007 Published: 16 August 2007
Abstract
Total C and N were measured in whole soils (0–0.15, 0.15–0.35, and 0.35–0.65 m), light organic matter fractions (<1 g/cm3 (LF 1.0) and 1.0–1.7 g/cm3 (LF 1.7)) in surface soils, and in leaf litter collected from a mixed grass/lucerne pasture and adjacent native bush at Moora, Western Australia. The C content of the plant material and light fractions was characterised by 13C cross-polarisation/magic angle spinning nuclear magnetic resonance (13C CP/MAS NMR) spectroscopy. Water-extractable organic C (WEOC) and N (WEON) were measured in soil, and dissolved organic C (DOC) and N (DON) were measured in soil solutions. In addition, both NO3-N and NH4-N (SMN) were measured in soil solutions and water extracts.
Total soil C (0–0.65 m) did not differ significantly between land uses, but there was clear evidence of N enrichment under the pasture system, which contained significantly (P < 0.05) more total N in the surface soil (0–0.15 m) compared with that under native bush. The significantly (P < 0.05) smaller C/N ratios of the surface soil, plant litter, and light fractions (LF 1.0 and 1.7) under the pasture provided further evidence of N enrichment. The 13C CP/MAS NMR spectra for plant material and light fractions did not differ greatly between landuses, but in both cases the O-alkyl : alkyl carbon ratio declined with increasing density. The decomposition and subsequent mineralisation of the relatively N-rich organic matter fractions in the pasture system may have contributed to the significantly (P < 0.05) greater DOC, DON, and SMN concentration measured in soil solutions under pasture compared with those under native bush.
Additional keywords: 13C CP/MAS NMR, dissolved organic matter, extractable organic matter, light fraction.
Acknowledgments
The work of A. Macdonald was supported in part by a fellowship from the Organisation for Economic Co-operation and Development under the Co-operative research programme on Biological Resources Management for Sustainable Agricultural Systems. D. V. Murphy was supported by an Australian Grains Research and Development Corporation Research Fellowship. Rothamsted Research receives grant-aided support from the Biotechnology and Biological Sciences Research Council of the United Kingdom. Additional support was provided by the UK Natural Environmental Research Council. We thank Nui Milton for assistance with the analytical work.
Abbott I,
Parker CA, Sills ID
(1979) Changes in the abundance of large soil animals and physical properties of soils following cultivation. Australian Journal of Soil Research 17, 343–353.
| Crossref | GoogleScholarGoogle Scholar |
Anderson GC,
Fillery IR,
Dolling PJ, Asseng S
(1998a) Nitrogen and water flows under pasture–wheat and lupin–wheat rotations in deep sands in Western Australia 1. Nitrogen fixation in legumes, net N mineralisation, and utilisation of soil-derived nitrogen. Australian Journal of Agricultural Research 49, 329–344.
| Crossref | GoogleScholarGoogle Scholar |
Anderson GC,
Fillery IR,
Dunin FX,
Dolling PJ, Asseng S
(1998b) Nitrogen and water flows under pasture–wheat and lupin–wheat rotations in deep sands in Western Australia 2. Drainage and nitrate leaching. Australian Journal of Agricultural Research 49, 345–361.
| Crossref | GoogleScholarGoogle Scholar |
Barrios E,
Buresh RJ, Sprent JI
(1996) Nitrogen mineralization in density fractions of soil organic matter from maize and legume systems. Soil Biology & Biochemistry 28, 1459–1465.
| Crossref | GoogleScholarGoogle Scholar |
Cabrera ML, Beare MH
(1993) Alkaline persulphate oxidation for determining total nitrogen in microbial biomass extracts. Soil Science Society of America Journal 57, 1007–1012.
Chen CR,
Xu ZH, Mathers NJ
(2004) Soil carbon pools in adjacent natural and plantation forest of subtropical Australia. Soil Science Society of America Journal 68, 282–291.
Cookson WR,
Abaye D,
Marschner P,
Murphy DV,
Stockdale EA, Goulding KWT
(2005) The contribution of soil organic matter fractions to carbon and nitrogen mineralization and microbial community size and structure. Soil Biology & Biochemistry 37, 1726–1737.
| Crossref | GoogleScholarGoogle Scholar |
Dalal RC, Mayer RJ
(1986a) Long-term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland. I Overall changes in soil properties and trends in winter cereal yields. Australian Journal of Soil Research 24, 265–279.
| Crossref | GoogleScholarGoogle Scholar |
Dalal R, Mayer R
(1986b) Long-term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland. IV Loss of organic carbon from different density fractions. Australian Journal of Soil Research 24, 301–309.
| Crossref | GoogleScholarGoogle Scholar |
Danso SKA,
Hardarson G, Zapata F
(1988) Dinitrogen fixation estimates in alfalfa-ryegrass swards using different nitrogen-15 labelling methods. Crop Science 28, 106–110.
Dixon WT
(1982) Spinning-sideband-free and spinning-sideband-only NMR spectra in spinning samples. The Journal of Chemical Physics 77, 1800–1809.
| Crossref | GoogleScholarGoogle Scholar |
Golchin A,
Oades JM,
Skjemstad JO, Clarke P
(1994) Soil structure and carbon cycling. Australian Journal of Soil Research 32, 1043–1068.
| Crossref | GoogleScholarGoogle Scholar |
Golchin A,
Oades JM,
Skjemstad JO, Clarke P
(1995) Structural and dynamic properties of soil organic matter as reflected by 13C natural abundance, pyrolysis mass spectromerty and solid state 13C NMR spectroscopy in density fractions of an oxisol under forest and pasture. Australian Journal of Soil Research 33, 59–76.
| Crossref | GoogleScholarGoogle Scholar |
Grigg AM,
Pate JS, Unkovich MJ
(2000) Responses of native woody taxa in Banksia woodland to incursion of groundwater and nutrients from bordering agricultural land. Australian Journal of Botany 48, 777–792.
| Crossref | GoogleScholarGoogle Scholar |
Hassink J
(1995a) Decomposition rate constants of size and density fractions of soil organic matter. Soil Science Society of America Journal 59, 1631–1635.
Hassink J
(1995b) Density fractions of soil macroorganic matter and microbial biomass as predictors of C and N mineralization. Soil Biology & Biochemistry 27, 1099–1108.
| Crossref | GoogleScholarGoogle Scholar |
Henriksen A, Selmer-Olsen AR
(1970) Automatic methods for determining nitrate and nitrite in water and soil extracts. The Analyst 95, 514–518.
| Crossref | GoogleScholarGoogle Scholar |
Jones DL,
Shannon D,
Murphy D, Farrar J
(2004) Role of dissolved organic N (DON) in soil N cycling in grassland soils. Soil Biology & Biochemistry 36, 749–756.
| Crossref | GoogleScholarGoogle Scholar |
Jones DL, Willett VB
(2006) Experimental evaluation of methods to quantify dissolved organic nitrogen (DON) and dissolved carbon (DOC) in soil. Soil Biology & Biochemistry 38, 991–999.
| Crossref | GoogleScholarGoogle Scholar |
Kalbitz K,
Solinger S,
Park JH,
Michalzik B, Matzner E
(2000) Controls on the dynamics of dissolved organic matter in soils: a review. Soil Science 165, 277–304.
| Crossref | GoogleScholarGoogle Scholar |
Krom MD
(1980) Spectrophotometric determination of ammonia: a study of a modified Berthelot reaction using salicylate and dichloroisocyanurate. The Analyst 105, 305–316.
| Crossref | GoogleScholarGoogle Scholar |
Low AB, Lamont BB
(1990) Aerial and below-ground Phytomass of Banksia Scrub-heath at Enebha, South-western Australia. Australian Journal of Botany 38, 351–359.
| Crossref | GoogleScholarGoogle Scholar |
Macdonald AJ,
Poulton PR,
Stockdale EA,
Powlson DS, Jenkinson DS
(2002) The fate of residual 15N-labelled fertilizer in arable soils: its availability to subsequent crops and retention in soil. Plant and Soil 246, 123–137.
| Crossref | GoogleScholarGoogle Scholar |
Marschner B, Kalbitz K
(2003) Controls of bioavailability and biodegradability of dissolved organic matter in soils. Geoderma 113, 211–235.
| Crossref | GoogleScholarGoogle Scholar |
Mathers NJ,
Mao XA,
Xu ZH,
Saffigna PG,
Berners-Price SJ, Perera MCS
(2000) Recent advances in the application of 13C and 15N NMR spectroscopy to soil organic matter studies. Australian Journal of Soil Research 38, 769–787.
| Crossref | GoogleScholarGoogle Scholar |
McNeill AM,
Sparling GP,
Murphy DV,
Braunberger P, Fillery IRP
(1998) Changes in extractable and microbial C, N and P in a Western Australian wheatbelt soil following simulated summer rainfall. Australian Journal of Soil Research 36, 841–854.
| Crossref | GoogleScholarGoogle Scholar |
Mendham DS,
Mathers NJ,
O’Connell
,
Grove TS, Saffigna PG
(2002) Impact of land-use on soil organic matter quality in south-western Australia – characterisation with 13C CP/MAS NMR spectroscopy. Soil Biology & Biochemistry 34, 1669–1673.
| Crossref | GoogleScholarGoogle Scholar |
Muller MM,
Sundman V,
Soininvaara O, Meriliainen A
(1988) Effect of chemical composition on the release of nitrogen from agricultural plant materials decomposing in soil under field conditions. Biology and Fertility of Soils 6, 78–83.
| Crossref | GoogleScholarGoogle Scholar |
Murphy DV,
Macdonald AJ,
Stockdale EA,
Goulding KWT,
Fortune S,
Gaunt JL,
Poulton PR,
Wakefield JA,
Webster CP, Wilmer WS
(2000) Soluble organic nitrogen in agricultural soils. Biology and Fertility of Soils 30, 374–387.
| Crossref | GoogleScholarGoogle Scholar |
Osler GHR, Murphy DV
(2005) Oribatid mite species richness and soil organic matter fractions in agricultural and native vegetation soils in Western Australia. Applied Soil Ecology 29, 93–98.
| Crossref | GoogleScholarGoogle Scholar |
Pate JS,
Stewart GR, Unkovich M
(1993) 15N natural abundance of plant and soil components of a Banksia woodland ecosystem in relation to nitrate utilization, life form, mycorrhizal status and N2-fixing abilities of component species. Plant, Cell & Environment 16, 365–373.
| Crossref | GoogleScholarGoogle Scholar |
Pate JS,
Unkovich MJ,
Armstrong EL, Sanford P
(1994) Selection of reference plants for 15N natural abundance assessment of N2 fixation by crops and pasture legumes in South-West Australia. Australian Journal of Agricultural Research 45, 133–147.
| Crossref | GoogleScholarGoogle Scholar |
Powlson DS,
Jenkinson DS,
Pruden G, Johnston AE
(1985) The effect of straw incorporation on the uptake of nitrogen by winter wheat. Journal of the Science of Food and Agriculture 36, 26–30.
| Crossref | GoogleScholarGoogle Scholar |
Rahn CR, Lillywhite R
(2002) A study of quality factors affecting the short term decomposition of field vegetable residues. Journal of the Science of Food and Agriculture 82, 19–26.
| Crossref | GoogleScholarGoogle Scholar |
Sohi SP,
Mahieu N,
Arah JRM,
Powlson DS,
Madari B, Gaunt JL
(2001) A procedure for isolating soil organic matter fractions suitable for modelling. Soil Science Society of America Journal 65, 1121–1128.
Sollins P,
Spycher G, Glassman CA
(1984) Net nitrogen mineralization from light- and heavy-fraction forest soil organic matter. Soil Biology & Biochemistry 16, 31–37.
| Crossref | GoogleScholarGoogle Scholar |
Standish RJ,
Cramer VA,
Hobbs RJ, Kobryn HT
(2006) Legacy of land-use evident in soils of Western Australia’s wheat belt. Plant and Soil 280, 189–207.
| Crossref | GoogleScholarGoogle Scholar |
Thorup-Kristensen K
(1994) An easy pot incubation method for measuring nitrogen mineralization from easily decomposable organic material under well defined conditions. Fertilizer Research 38, 239–247.
| Crossref | GoogleScholarGoogle Scholar |
Unkovich MJ,
Pate JS, Hamblin J
(1994) The nitrogen economy of broadacre lupin in southwest Australia. Australian Journal of Agricultural Research 45, 149–164.
| Crossref | GoogleScholarGoogle Scholar |
Waksman SA, Tenney FG
(1927) The composition of natural organic materials and their decomposition in the soil II. Influence of age of plant upon the rapidity and nature of its decomposition - rye plants. Soil Science 24, 317–333.
Ward PR,
Fillery IRP,
Maharaj EA, Dunin FX
(2003) Water budgets and nutrients in a native Banksia woodland and an adjacent Medicago sativa pasture. Plant and Soil 257, 305–319.
| Crossref | GoogleScholarGoogle Scholar |