02718naa a2200277 a 450000100080000000500110000800800410001910000220006024500410008226000090012330000150013249000490014750000150019652019680021165000250217965000140220465000110221865000150222965000150224465000130225965000120227265300270228470000170231170000200232877300920234810290672016-10-18       2005    bl uuuu     u00u1 u    #d1 aROYO PALLARES, O.  aThe South American campos ecosystem.  c2005  ap. 171-219  a(Plant Production and Protection Series; 34)  aChapter 5.  aThe Campos, grassland  with few trees or shrubs except near streams, lies between 24°S  and  35°S;  it  includes  parts  of  Brazil  ,  Paraguay  and  Argentina  ,  and  all  of  Uruguay  .  Grassland  -based  livestock  production  is  very  important,  based  on  the  natural   grassland that covers most of the area. Stock rearing is on large, delimited holdings and is commercial. Both tussock-grass  and short-grass    grasslands occur.  There is a dominance of summer -growing  C4 grasses, with C3  grasses associated with the winter  cycle. Cattle  and horses were introduced in the seventeenth cen- tury and sheep  in the nineteenth. Production is based on spring –summer growing  grassland,  with  little  use  of  sown      pastures.  Beef  cattle    predominate;  sheep  are  mainly  for  wool,  but  some  lamb  is  produced.  Limited  winter  production  and poor herbage quality are major limiting factors in livestock production. Soil phosphorus  is  generally  low  and  this  deficiency      affects  stock.  Campos  pastures  are highly responsive to fertilizers, which can modify the specific composition of natural grassland; application of phosphate increases legume cover and the phosphorus content of forage. Fattening off grass can take up to four years; intensive fattening  of  younger  stock  uses  some  sown  pasture    .  Sheep    may  be  grazed  with  breeding  herds  of  cattle.  Exotic  temperate        legumes  can  be  grown  and  may  be  over-sown  into  native        swards  after  land  preparation;  once  established,  legumes  encourage  the  development      of  winter  grasses.  This  paper  shows  that  it  is  possible to improve forage consumption from natural grasslands, implying an annual increase of 784 000 tonne of liveweight, without cost, in Rio Grande do Sul alone, through a strategy of high forage offer  to the grazing    animal, which also optimizes forage accumulation rates  in the pasture.  aAPLICACION DE ABONOS  aARGENTINA  aBRASIL  aECOSISTEMA  aPASTIZALES  aPRADERAS  aURUGUAY  aSISTEMAS DE PRODUCCION1 aBERRETTA, E.1 aMARASCHIN, G.E.  tIn: Suttie, J.M.; Reynolds, S.G.; Batello, C. Grasslands of the world. Roma: FAO, 2005.