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RESEARCH ARTICLE

The potential for sown tropical perennial grass pastures to improve soil organic carbon in the North-West Slopes and Plains of New South Wales

G. D. Schwenke A D , M. K. McLeod A , S. R. Murphy A , S. Harden A , A. L. Cowie B and V. E. Lonergan C
+ Author Affiliations
- Author Affiliations

A NSW Department of Primary Industries, Tamworth Agricultural Institute, 4 Marsden Park Road, Calala, NSW 2340, Australia.

B Rural Climate Solutions, University of New England, NSW Department of Primary Industries, Armidale, NSW 2351, Australia.

C School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.

D Corresponding author. Email: graeme.schwenke@dpi.nsw.gov.au

Soil Research 51(8) 726-737 https://doi.org/10.1071/SR13200
Submitted: 18 December 2012  Accepted: 15 August 2013   Published: 20 December 2013

Abstract

Sown tropical perennial grass pastures may be a means to restore soil organic carbon (C) lost by cropping with conventional tillage to the levels originally present in native grass pastures. To assess this, total organic carbon and related soil properties were measured under sown tropical pastures, conventionally cultivated cropping, and native pastures on 75 Chromosols and 70 Vertosols to 0.3 m depth in the New South Wales North-West Slopes and Plains region of Australia. The impact of several perennial pasture species on soil organic carbon was also assessed in a 6-year-old, sown pasture experiment on a previously cropped Chromosol.

Soil cores in 0.1-m segments to 0.3 m were analysed for total organic carbon, total nitrogen (N), pH, and phosphorus (Colwell-P). Mid-infrared scans were used to predict the particulate, humus, and resistant fractions of the total organic carbon. Bulk density was used to calculate stocks of C, N, and C fractions.

In Chromosols, total organic carbon in the surface 0–0.1 m was greater under sown tropical pastures (23.1 Mg ha–1) than conventional tillage cropping (17.7 Mg ha–1), but still less than under native pastures (26.3 Mg ha–1). Similar land-use differences were seen for particulate and resistant organic C, and total N. The proportional differences between land uses were much greater for particulate organic C than other measures, and were also significant at 0.1–0.2 and 0.2–0.3 m. Subsurface bulk density (0.1–0.2 m) was lower under sown tropical pastures (1.42 Mg m–3) than conventionally tilled cropping (1.52 Mg m–3). For Vertosols, total organic carbon in the surface 0–0.1 m was greater under sown tropical pastures (19.0 Mg ha–1) and native pastures (20.5 Mg ha–1) than conventional tillage cropping (14.0 Mg ha–1). Similar land-use effects were seen for the particulate and humus organic C fractions, and total N.

In the sown pasture species experiment, there was no significant difference in total N, total organic carbon, or any C fraction between soils under a native-grass species mixture, two improved tropical grass species, or a perennial pasture legume. Regular monitoring is required to better discern whether gradual changes are being masked by spatial and temporal variation.

The survey results support previous research on Vertosols within the New South Wales North-West Slopes and Plains that show sown tropical grass pastures can improve total organic carbon. Improvements in total organic carbon on Chromosols have not previously been documented, so further targeted soil monitoring and experimentation is warranted for the region.


References

Baldock JA, Hawke B, Sanderman J, MacDonald LM (2013a) Predicting contents of carbon and its component fractions in Australian soils from diffuse reflectance mid-infrared spectra. Soil Research 51, 577–595.

Baldock JA, Sanderman J, MacDonald LM, Puccini A, Hawke B, Szarvas S, McGowan J (2013b) Quantifying the allocation of soil organic carbon to biologically significant fractions. Soil Research 51, 561–576.

Blair N, Crocker GJ (2000) Crop rotation effects on soil carbon and physical fertility of two Australian soils. Australian Journal of Soil Research 38, 71–84.
Crop rotation effects on soil carbon and physical fertility of two Australian soils.Crossref | GoogleScholarGoogle Scholar |

Chan KY (1997) Consequences of changes in particulate organic carbon in Vertisols under pasture and cropping. Soil Science Society of America Journal 61, 1376–1382.
Consequences of changes in particulate organic carbon in Vertisols under pasture and cropping.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXmvV2gt7s%3D&md5=4e5a1bb125b3c53e6784946f865465b5CAS |

Chan K, Bellotti W, Roberts W (1988) Changes in surface soil properties of vertisols under dryland cropping in a semiarid environment. Australian Journal of Soil Research 26, 509–518.
Changes in surface soil properties of vertisols under dryland cropping in a semiarid environment.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXjvVaisw%3D%3D&md5=0efe174e500cf1ff8f75e4e0f23e7cebCAS |

Chan KY, Hodgson AS, Bowman AM (1995) Degradation of Australian vertisols after conversion from native grassland (Astrebla lappacea) to continuous cropping in a semi-arid subtropical environment. Tropical Grasslands 29, 210–217.

Chan KY, Bowman AM, Friend JJ (1997) Resoration of soil fertility of degraded vertisols using a pasture including a native grass (Astrebla lappacea). Tropical Grasslands 31, 145–155.

Chan KY, Heenan DP, So HB (2003) Sequestration of carbon and changes in soil quality under conservation tillage on light-textured soils in Australia: a review. Australian Journal of Experimental Agriculture 43, 325–334.
Sequestration of carbon and changes in soil quality under conservation tillage on light-textured soils in Australia: a review.Crossref | GoogleScholarGoogle Scholar |

Chan KY, Oates A, Li GD, Conyers MK, Prangnell RJ, Poile G, Liu DL, Barchia IM (2010) Soil carbon stocks under different pastures and pasture management in the higher rainfall areas of south-eastern Australia. Australian Journal of Soil Research 48, 7–15.
Soil carbon stocks under different pastures and pasture management in the higher rainfall areas of south-eastern Australia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXisVCgtbc%3D&md5=6ba9a0bc46d097b10197775c381d6d78CAS |

Dalal RC, Chan KY (2001) Soil organic matter in rainfed cropping systems of the Australian cereal belt. Australian Journal of Soil Research 39, 435–464.
Soil organic matter in rainfed cropping systems of the Australian cereal belt.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXks1Kqt7c%3D&md5=a0808765b25458ef717e39818258119cCAS |

Dalal RC, Mayer RJ (1986) Long term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland. II. Total organic carbon and its rate of loss from the soil profile. Australian Journal of Soil Research 24, 281–292.
Long term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland. II. Total organic carbon and its rate of loss from the soil profile.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL28XkvFKmsLw%3D&md5=a5054bec44ec9ebf5e5109c3f6e2c1c4CAS |

Dalal RC, Strong WM, Weston EJ, Cooper JE, Lehane KJ, King AJ, Chicken CJ (1995) Sustaining productivity of a Vertisol at Warra, Queensland, with fertilisers, no-tillage, or legumes. 1. Organic matter status. Australian Journal of Experimental Agriculture 35, 903–913.
Sustaining productivity of a Vertisol at Warra, Queensland, with fertilisers, no-tillage, or legumes. 1. Organic matter status.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28Xhs1yiu7c%3D&md5=6169ca7c97a3b9096c94682d45366561CAS |

Dalal RC, Allen DE, Wang WJ, Reeves S, Gibson I (2011) Organic carbon and total nitrogen stocks in a Vertisol following 40 years of no-tillage, crop residue retention and nitrogen fertilisation. Soil & Tillage Research 112, 133–139.
Organic carbon and total nitrogen stocks in a Vertisol following 40 years of no-tillage, crop residue retention and nitrogen fertilisation.Crossref | GoogleScholarGoogle Scholar |

Daniells IG, Brown R, Hayman P (1996) Benchmark values for soil nitrogen and carbon in soils of the northern wheat-belt of NSW. Agricultural Resource Management Report Series, NSW Agriculture, Orange, NSW.

Ellert BH, Bettany JR (1995) Calculation of organic matter and nutrients stored in soils under contrasting management regimes. Canadian Journal of Soil Science 75, 529–538.
Calculation of organic matter and nutrients stored in soils under contrasting management regimes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XhslKlsbo%3D&md5=2c31928b3873b1fbb2727b449836b997CAS |

Fernandes M, Krull E (2008) How does acid treatment to remove carbonates affect the isotopic and elemental composition of soils and sediments? Environmental Chemistry 5, 33–39.
How does acid treatment to remove carbonates affect the isotopic and elemental composition of soils and sediments?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXitlagsbk%3D&md5=53a31ce81e14df170f79d934befe3f5aCAS |

Hallsworth EG, Gibbons FR, Lemerle TH (1954) The nutrient status and cultivation practices of the soils of the north-west wheat belt of New South Wales. Australian Journal of Agricultural Research 5, 422–447.
The nutrient status and cultivation practices of the soils of the north-west wheat belt of New South Wales.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaG2cXotVSrtQ%3D%3D&md5=e72467291b951fadbce729260154bb4cCAS |

Harte AJ (1984) Effect of tillage on the stability of three red soils of the northern wheat belt. Journal of Soil Conservation Service NSW 40, 94–101.

Haydock K, Shaw N (1975) The comparative yield method for estimating dry matter yield of pasture. Australian Journal of Experimental Agriculture 15, 663–670.

Holford ICR (1990) Effects of 8-year rotations of grain sorghum with lucerne, annual legume, wheat and long fallow on nitrogen and organic carbon in two contrasting soils. Australian Journal of Soil Research 28, 277–291.
Effects of 8-year rotations of grain sorghum with lucerne, annual legume, wheat and long fallow on nitrogen and organic carbon in two contrasting soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3cXmtFSks7s%3D&md5=b4991131d719d64de5c217e40e3ddf2aCAS |

Isbell RF (2002) ‘The Australian Soil Classification.’ Revised edn (CSIRO Publishing: Melbourne)

Lawes RA, Robertson MJ (2012) Effect of subtropical perennial grass pastures on nutrients and carbon in coarse-textured soils in a Mediterranean climate. Soil Research 50, 551–561.
Effect of subtropical perennial grass pastures on nutrients and carbon in coarse-textured soils in a Mediterranean climate.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xhs12jsrjN&md5=3cea76d4b16abc565de42a53165359ddCAS |

Lodge GM, Brennan MA, Harden S (2010) Field studies of the effects of pre-sowing weed control and time of sowing on tropical perennial grass establishment, North-West Slopes, New South Wales. Crop & Pasture Science 61, 182–191.
Field studies of the effects of pre-sowing weed control and time of sowing on tropical perennial grass establishment, North-West Slopes, New South Wales.Crossref | GoogleScholarGoogle Scholar |

McCormick LH, Boschma SP, Lodge GM, Scott JF (2009) Producer-identified constraints to widespread adoption of sown tropical grass pastures on the north-west slopes of New South Wales. Tropical Grasslands 43, 263–266.

McCormick LH, Lodge GM, Murphy SR, McGufficke BR, Harris CA, Boschma SP (2012) Tropical perennial grasses and hardseeded legumes—Examples of using species adaptation in a changing climate. In ‘Climate Adaptation in Action 2012: Sharing knowledge to adapt’. (National Climate Change Adaptation Research Facility, Griffith University: Southport, Qld)

McGufficke BR, McCormick LH (2010) Tropical perennial grasses for northern inland NSW. Primefacts No. 105, August 2010. Industry and Investment NSW, Orange, NSW.

Murphy SR (2010) Tropical perennial grasses—root depths, growth and water use efficiency. Primefacts No. 1027, June 2010. Industry and Investment NSW, Orange, NSW.

Murphy B, Rawson A, Ravenscroft L, Rankin M, Millard R (2003) Paired site sampling for soil carbon estimation—New South Wales. National Carbon Accounting System, Technical Report No. 34. Australian Greenhouse Office, Canberra, ACT.

Murphy SR, Lodge GM, Brennan MA (2010) Tropical grass pastures capture winter rainfall. In ‘25th Annual Conference of the Grassland Society of NSW 2010’. (Eds C Waters, D Garden) pp. 137–140. (Grassland Society of NSW Orange, NSW)

Rayment GE, Lyons DJ (2011) ‘Soil chemical methods—Australasia.’ (CSIRO Publishing: Melbourne)

Sanderman J, Fillery IRP, Jongepier R, Massalsky A, Roper MM, Macdonald LM, Maddern T, Murphy DV, Wilson BR, Baldock JA (2013) Carbon sequestration under subtropical perennial pastures I: Overall trends. Soil Research 51, 760–770.

Skjemstad JO, Dalal RC, Janik LJ, McGowan JA (2001) Changes in chemical nature of soil organic carbon in Vertisols under wheat in south-eastern Queensland. Australian Journal of Soil Research 39, 343–359.
Changes in chemical nature of soil organic carbon in Vertisols under wheat in south-eastern Queensland.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXivVaisrs%3D&md5=a0d3d216fb685d4b5e1987f6c0ba7973CAS |

Speight JG (2009) Landform. In ‘Australian soil and land survey field handbook’. 3rd edn (CSIRO Publishing: Melbourne)

Whitbread AM, Lefroy RDB, Blair GJ (1998) A survey of the impact of cropping on soil physical and chemical properties in north-western New South Wales. Australian Journal of Soil Research 36, 669–682.
A survey of the impact of cropping on soil physical and chemical properties in north-western New South Wales.Crossref | GoogleScholarGoogle Scholar |

Wilson BR, Growns I, Lemon J (2008) Land-use effects on soil properties on the north-western slopes of New South Wales: Implications for soil condition assessment. Australian Journal of Soil Research 46, 359–367.
Land-use effects on soil properties on the north-western slopes of New South Wales: Implications for soil condition assessment.Crossref | GoogleScholarGoogle Scholar |

Young R, Wilson BR, McLeod M, Alston C (2005) Carbon storage in the soils and vegetation of contrasting land uses in northern New South Wales, Australia. Australian Journal of Soil Research 43, 21–31.
Carbon storage in the soils and vegetation of contrasting land uses in northern New South Wales, Australia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtl2ku7c%3D&md5=da9b0a5300736072f35989e42380a978CAS |

Young RR, Wilson B, Harden S, Bernardi A (2009) Accumulation of soil carbon under zero tillage cropping and perennial vegetation on the Liverpool Plains, eastern Australia. Australian Journal of Soil Research 47, 273–285.
Accumulation of soil carbon under zero tillage cropping and perennial vegetation on the Liverpool Plains, eastern Australia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXmtlWrtbY%3D&md5=007d3833e7eff336abf40f5b29ecb532CAS |