9905 1 archive 5901 disk0/00/00/99/05 2007-03-06 2009-08-20 14:34:50 2009-08-20 14:34:50 conference_item show 0 en The final version of this paper is published in: Niggli, Urs; Leifert, Carlo; Alföldi, Thomas; Lück, Lorna and Willer, Helga, Eds. (2007) Improving Sustainability in Organic and Low Input Food Production Systems. Proceedings of the 3rd International Congress of the European Integrated Project Quality Low Input Food (QLIF). University of Hohenheim, Germany, March 20 – 23, 2007. Research Institute of Organic Agriculture FiBL, CH-Frick.http://orgprints.org/10417/ Printed copies may be ordered from the FiBL Shop at www.shop.fibl.org. int_conf_2007qlif_3_crops March 20-23, 2007 3rd QLIF Congress: Improving Sustainability in Organic and Low Input Food Production Systems University of Hohenheim, Germany never 0 TRUE paper Cornish P. S. pub 4nutrient farm_nutrient_management phosphorus, Australia, soil fertility, grain, grazing Two case-study farms with negative P balances maintained acceptable productivity without fertilisers, apparently by ‘mining’ ‘available’ P reserves in surface and subsoil. The question for these organic farms is ‘how long before fertiliser is needed?’ With six farms on lower-fertility, weakly acidic to alkaline soils and modest rainfall (380-580 mm/yr), low productivity was related to P deficiency despite positive P balances from using allowable fertilisers. Useful supplies of compost or manure were unavailable. Until effective allowable fertilisers or microbial inoculants have been developed, there is a case for using soluble forms of P fertiliser on soils where soil-solution P is low and soil P-sorption is high, so that additions of soluble P ‘feed the soil, not the plant’. 2007 published public 7238 1 9905 1 application/pdf de public

Cornish-2007-phosphorus_management.pdf

Cornish-2007-phosphorus_management.pdf 242219 http://orgprints.org/9905/1/Cornish-2007-phosphorus_management.pdf