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Nitrogen immobilization in decomposing litter contributes to productivity decline in ageing pastures of green panic (Panicum maximum var. trichoglume)

  • G. B. Robbins (a1), J. J. Bushell (a1) and G. M. McKeon (a1)

The extent and rate of N release from nylon bags containing green panic (Panicum maximumvar.trichoglume)litter was measured for up to 319 days (long-term studies) in 1978/79 and 1979/80 in Gayndah, Australia. Dry matter (DM) decomposition rates were measured in 41 periods of 39 days and related to environmental variables and initial litter N concentrations (short-term study).

About half of litter DM decomposed during the long-term studies, while N concentration in the remaining litter increased from an initial average of 0–57 % N, to 0–95 % N. Net release of N from bags began when its concentration in the residue increased to c.0–65% N (or when the C:N ratio decreased to 75:1). Only a net 20–30 % of the initial N was released for potential plant uptake by the end of the study. The short-term study showed that DM decomposition was rapid and independent of pasture age. Decomposition rate increased with soil moisture and average daily temperature but was unaffected by initial litter N concentration. Release of N from decomposing litter was slow, despite rapid DM decomposition. It was concluded that a major cause of declining productivity in sown grass pastures is the immobilization of N in decomposing grass litter.

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C. M. Britton , J. D. Dodd & A. T. Wiechert (1978). Net aerial primary production of an Andropogon-Paspalum grassland ecosystem. Journal of Range Management 31, 381386.

T. W. G. Graham , A. A. Webb & S. A. Waring (1981). Soil nitrogen status and pasture productivity after clearing of brigalow (Acacia harpophylla). Australian Journal of Experimental Agriculture and Animal Husbandry 21, 109118.

H. W. Hunt (1977). A simulation model for decomposition in grasslands. Ecology, USA 58, 469484.

E. B. Knapp , L. F. Elliott & G. S. Campbell (1983a). Microbial respiration and growth during the decomposition of wheat straw. Soil Biology and Biochemistry 15, 319323.

E. B. Knapp , L. F. Elliott & G. S. Campbell (1983b). Carbon, nitrogen and microbial biomass interrelationships during the decomposition of wheat straw: a mechanism simulation model. Soil Biology and Biochemistry 15, 455461.

R. L. McCown (1973). An evaluation of the influence of available soil water storage capacity on growing season length and yield of tropical pastures using simple water balance models. Agricultural Meteorology 11, 5360.

V. Meentemeyer (1978). Macroclimate and lignin control of litter decomposition rates. Ecology, USA 59, 465472.

J. J. Mott , G. M. McKeon , C. J. Gardener & L. T Mannetje (1981). Geographic variation in the reduction of hardseed content of Stylosanthesseeds in the tropics and subtropics of northern Australia. Australian Journal of Agricultural Research 32, 861869.

N. G. Seligman , S. Feigenhaum , D. Feinerman & R. W. Benjamin (1986). Uptake of nitrogen from high Cto-N ratio, 15N labelled organic residues by spring wheat grown under semi-arid conditions. Soil Biology and Biochemistry 18, 303307.

R. K. Wieder & G. E. Lang (1982). A critique of the analytical methods used in examining decomposition data from litter bags. Ecology, USA 63, 16361642.

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The Journal of Agricultural Science
  • ISSN: 0021-8596
  • EISSN: 1469-5146
  • URL: /core/journals/journal-of-agricultural-science
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