02658nam a2200421 a 450000100080000000500110000800800410001910000130006024501490007326000460022230000110026850000180027952015440029765000230184165000130186465000150187765000240189265000140191665000180193065000160194865000240196465000270198865000250201565000130204065000120205365000110206565000160207665000150209265000180210765000170212565300170214265300110215965300120217065300100218265300150219265300170220765300120222417908432018-07-05       1979    bl uuuu  m   00u1 u    #d1 aPOTT, A.  aEffects of sheep grazing and treading and of shading on the growth and population dynamics of Lotononis bainesii grown with Digitaria decumbens.  aAustralia: University of Queenslandc1979  a241 p.  aPh.D. Thesis.  aThe productivity and persistence of Lotononis bainesii cv. Miles grown with Digitaria decumbens cv. pangola was studied in two field experiments (exp.-1 grazing intensity, and exp.-2 treading), conducted at the University of Queensland Research Station at Mt. Cotton, on a red-yellow podzolic soil. A glasshouse experiment (exp.-3 shading) at St. Lucia contrasted the shade tolerance of the two species. Exp.-1 lasted two years, and comprised 4 stocking rates (7, 14, 21 and 28 sheep ha-1); six replicates were grazed in rotation (3 days on, 15 days off). Pasture dry matter yields and botanical composition were assessed three-monthly, and Lotononis demography was monitored by tagging individual plants in permanent quadrats, core sampling for stolon nodal root population and soil seed reserves (flotation recovery); in addition, soil bulk density was estimated. Lotononis did not persist under grazing regardless of stockinh rate. It behaved as a short-lived plant, predominantly annual, with some (insufficient) vegetative perennation (stolon rooted units) under heavy grazing. Soil seed reserves were 550 seeds m-2 (1.6 kg ha -1) under 21-28 sheep ha-1, compared to 4500 seeds m-2 (13 kg ha-1) under lenient grazing. Lotononis failed to regenerate under Pangola shading/or inopportune high grazing pressure, and there was no ideal level of stocking rate. Soil bulk density (top 7 cm) increased from 1.2 g cm-3 under 7 sheep ha-1 to 1.4 g cm-2 under 21 sheep ha-1. Exp.-2 was carried out on a Lotononis/Pangola sward using Edmond's...  aLotononis bainesii  apastures  apopulation  apopulation dynamics  aAgronomia  aCapim Pangola  aCrescimento  aDigitaria Decumbens  aDinâmica Populacional  aGramínea Forrageira  aPastagem  aPastejo  aPlanta  aPopulação  aProdução  aProdutividade  aSombreamento  aFeed grasses  aGrowth  aPasture  aPlant  aProduction  aProductivity  aShading