Record ID No. |
2027 |
Author(s) |
Martin R.C., Lynch D.H., Frick B., vanStraaten P , 2007 |
Affiliation |
Nova Scotia Agr Coll, Organ Agr Ctr Canada, Truro, NS B2N 5E3, CANADA |
Title |
Phosphorus status on Canadian organic farms |
Source. Vol.(no):Page |
Journal of the Science of Food and Agriculture.87(15):2737-2740p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Biochemistry |
Sub-subjects |
Miscellaneous |
Organism |
n.a. |
Country |
CANADA, America |
Abstracts |
In eastern North America, many conventional livestock farms, especially dairy
farms with high inputs of feed and fertiliser have excess soil phosphorus levels and an annual
phosphorus surplus. However, a Canadian dairy farm in transition to organic, without fertiliser
inputs reduced its farm P surplus to a marginal level. On long-term organic dairy farms in
Ontario, most soils tested low to very low in available P as measured by a standard soil test.
Canadian Prairie organic grain farms also consistently demonstrate deficiencies in available soil
P. Organic producers have few viable alternatives for P management. Phosphate rock can be
acceptable to organic standards (provided they are low in heavy metals, and not processed
synthetically), but the P in these becomes available slowly, especially in high pH soils common
on most organic farms in Canada. An alternative is to increase soil P availability. Enhanced
microbial activity in organically managed soils may make P more available. Livestock manures are
rich sources of available phosphorus, but a majority of organic farmers in Canada do not keep
livestock. Off-farm manure sources are subject to organic regulations and hauling costs, both of
which may be prohibitive. Furthermore, manure from conventional farms in Canada may be
contaminated by genetically modified material from corn and soybean feed. Additional research is
required to improve short-tern. Availability of soil P and long-term replacement. (c) 2007
Society of Chemical Industry. |