Show simple item record

dc.contributor.authorGrace, PR
dc.contributor.authorOades, JM
dc.contributor.authorKeith, H
dc.contributor.authorHancock, TW
dc.date.accessioned2021-09-16T02:33:07Z
dc.date.available2021-09-16T02:33:07Z
dc.date.issued1995
dc.identifier.issn0816-1089en_US
dc.identifier.doi10.1071/ea9950857en_US
dc.identifier.urihttp://hdl.handle.net/10072/408040
dc.description.abstractThe Permanent Rotation Trial at the Waite Agricultural Research Institute in South Australia was established on a red-brown earth in 1925, with predominately cereal-long fallow rotations on 34 adjacent plots. The trial was upgraded in 1948 to include a greater proportion of pasture leys in the rotations and currently contains 11 treatments. The trial is unreplicated; however, each phase of a sequence is represented each year. Seven of the original rotations have remained in an unbroken sequence since 1925: continuous wheat (W), wheat-fallow (WF), wheat-peas (WPe), wheat-pasture-fallow (WPaF), wheatoats- fallow (WOF), wheat-barley-peas (WBPe), wheat-oats-pasture-fallow (WOPaF). For the 11 rotations, soil organic carbon (SOC) in the top 10 cm declined from 2.75% in 1925 to a mean value of 1.56% in 1993. One plot, which had reverted to permanent pasture in 1950, showed the smallest decline with an SOC content of 2.46% in 1993. The greatest declines in SOC were in the 4 original rotations that included fallow phases in the sequence (mean value of 1.22%). In the WF rotation the SOC content had declined from 2.75 to 1.04% during 68 years of cropping. Associated yield decreases showed that the treatment could not sustain production. Soil organic C declined linearly with increasing frequency of fallows and decreasing frequency of pasture in the rotations. Average grain yields (1925-93) in the 7 original sequences ranged from 2.64 t/ha in WOPaF to 0.89 t/ha in the continuous W plot. The linear decline in yields for WBPe, WPaF, WPe, and WOF treatments indicate a convergence in the 1990s under current management, with an average yield of 1.54 t/ha in 1993 and average SOC in the top 10 cm of 1.32%. We hypothesise that the gradual increase in grain yields from the continuous W plot since the 1960s is the result of a gradual build-up of light fraction organic material, which assists in the maintainence of structure and nutrient availability.en_US
dc.languageenen_US
dc.publisherCSIRO Publishingen_US
dc.relation.ispartofpagefrom857en_US
dc.relation.ispartofpageto857en_US
dc.relation.ispartofissue7en_US
dc.relation.ispartofjournalAustralian Journal of Experimental Agricultureen_US
dc.relation.ispartofvolume35en_US
dc.titleTrends in wheat yields and soil organic carbon in the Permanent Rotation Trial at the Waite Agricultural Research Institute, South Australiaen_US
dc.typeJournal articleen_US
dcterms.bibliographicCitationGrace, PR; Oades, JM; Keith, H; Hancock, TW, Trends in wheat yields and soil organic carbon in the Permanent Rotation Trial at the Waite Agricultural Research Institute, South Australia, Australian Journal of Experimental Agriculture, 1995, 35 (7), pp. 857-857en_US
dc.date.updated2021-09-16T01:54:11Z
gro.hasfulltextNo Full Text
gro.griffith.authorKeith, Heather


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

  • Journal articles
    Contains articles published by Griffith authors in scholarly journals.

Show simple item record