Login | Request Account (DAF staff only)

Physical rehabilitation of degraded krasnozems using ley pastures

Share this record

Add to FacebookAdd to LinkedinAdd to XAdd to WechatAdd to Microsoft_teamsAdd to WhatsappAdd to Any

Export this record

View Altmetrics

Bell, M.J., Bridge, B.J., Harch, G.R. and Orange, D.N. (1997) Physical rehabilitation of degraded krasnozems using ley pastures. Australian Journal of Soil Research, 35 (5). pp. 1093-1113. ISSN 0004-9573

[img]
Preview
PDF
460kB

Article Link: https://doi.org/10.1071/S97005

Abstract

The physical fertility of krasnozems and euchrozems (Red Ferrosols) in Australia has declined substantially as a result of continuous cropping. Much of this decline is associated with reduced levels of soil organic carbon and soil compaction due to vehicle trac when soils are too wet. We examined the impact of kikuyu (Pennisetum clandestinum) and Rhodes grass (Chloris gayana) pasture leys with various management inputs on the regeneration of physical fertility of continuously cropped krasnozems from 2 locations in the South Burnett region of southern Queensland.
Pasture leys significantly improved the physical fertility of continuously cropped soils within 2–4 years. The most significant effects were on the creation of improved surface and subsurface macroporosity, and in a reduction in surface crust formation under high energy rain due to improved aggregate stability. Final steady state infiltration rates under well-managed leys increased 4-fold compared with those in continuously cropped soil.

Pastures were unable to ameliorate compacted layers below approx. 15 cm, although significant improvements in hydraulic conductivity through these layers (and to depths of at least 70 cm) were made, presumably by creating of continuous biopores. Introduced earthworms improved pasture effectiveness in ameliorating this layer, but only to depths of 20 cm, while deep ripping during the ley phase was the most effective treatment.

Kikuyu was the more effective pasture species in overcoming soil physical infertility, particularly in terms of improving aggregate stability under rain. In addition, the ability of kikuyu to resist the compacting influence of cattle trampling during wet weather meant that rainfall infiltration eciency was maintained during the ley phase and management options on returning to cropping were more flexible (e.g. direct drill strategies can be used). However, if pastures were ungrazed, the advantages of kikuyu in soil physical restoration were evident in only 2 years.

Item Type:Article
Keywords:krasnozems, Red Ferrosols, ley pastures, grazing, soil fertility, earthworms, deep ripping
Subjects:Agriculture > Agriculture (General) > Soils. Soil science > Soil and crops. Soil-plant relationships. Soil productivity
Live Archive:26 Mar 2024 01:29
Last Modified:26 Mar 2024 01:29

Repository Staff Only: item control page

Downloads

Downloads per month over past year

View more statistics