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Q.1
Phosphorus can reach surface waters from:
Overland flow (runoff)
Tile outflow
Both overland flow and tile outflow
Q.2
In watercourses or lakes, where is phosphorus found?
In solution
Attached to suspended or settled sediments
In aquatic plants or animals
All of the above
Q.3
Are all forms of phosphorus a concern for aquatic ecosystems?
All are of concern - soluble forms are immediately available to algae but other forms have a longer term impact.
Only soluble phosphorus is a concern. The other forms have no impact on algae.
Fertilizer phosphorus is a concern, but not natural soil phosphorus.
US sources of phosphorus are the problem, not Canadian.
Q.4
Less than 1% of the total phosphorus in soil is available to crops. How much total phosphorus is in the top 15 cm (6") of a typical agricultural soil?
300-500 kg/ha
1,000-1,200 kg/ha
3,000-5,000 kg/ha
7,000-9,000 kg/ha
Q.5
Which best management practices can help to reduce phosphorus loss from field vegetable production?
Increasing nitrogen rates, erosion control structures, improving field drainage, no till
Soil testing, calibrating fertilizer application equipment, erosion control structures, maintaining soil cover all year
Controlled drainage, fall application of phosphorus, improving soil health, crop rotation
Fertilize with manure or compost only, cover crops, erosion control structures, soil testing
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