Premium
Measurement of Fertilizer Phosphorus Residues and Its Utilization
Author(s) -
Spratt E. D.,
Warder F. G.,
Bailey L. D.,
Read D. W. L.
Publication year - 1980
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1980.03615995004400060013x
Subject(s) - fertilizer , soil water , phosphorus , calcareous , environmental science , agronomy , sodium bicarbonate , soil test , mathematics , chemistry , soil science , botany , biology , organic chemistry
A values and sodium bicarbonate (NaHCO 3 ) extraction soil tests were used to determine phosphorus (P) levels over 8 years on four soils which had been treated with 0, 100, 200, and 400 kg P/ha. The tests correlated highly with each other and indicated the decline of residual fertilizer‐P over years as the soils were cropped. Reliable predictions for the duration of the beneficial effects of large amounts of fertilizer‐P could be made for the two Manitoba soils where cropping was continuous (wheat‐flax) but not for the Saskatchewan soils where fallow was included (wheat‐fallow). By using the linear equation of NaHCO 3 soil tests vs. time (years), it was predicted that 100, 200, and 400 kg P/ha would last about 6, 9, and 13 years, respectively, before further fertilizer‐P inputs were needed to maintain wheat production. Longer durations were predicted for 200 and 400 kg P/ha when curvilinear relationships were used, averaging 11 and 22 years, respectively, giving better economic feasibility. These soil testing techniques may be used on calcareous soils to minimize current fertilizer‐P inputs for wheat where residual fertilizer‐P has accumulated.