Premium
Assessing extractable soil phosphorus methods in estimating phosphorus concentrations in surface run‐off from Calcic Hapludolls
Author(s) -
Schindler F. V.,
Guidry A. R.,
German D. R.,
Gelderman R. H.,
Gerwing J. R.
Publication year - 2009
Publication title -
soil use and management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.709
H-Index - 81
eISSN - 1475-2743
pISSN - 0266-0032
DOI - 10.1111/j.1475-2743.2008.00189.x
Subject(s) - phosphorus , soil water , soil test , extraction (chemistry) , distilled water , environmental science , chemistry , environmental chemistry , soil science , hydrology (agriculture) , geology , chromatography , geotechnical engineering , organic chemistry
Understanding soil test phosphorus (STP) and surface run‐off phosphorus (P) relationships for soils is necessary for P management. The objective of the study was to evaluate the efficacy of various soil test indices to predict P losses in surface run‐off. Selected sites were subjected to in situ rainfall simulations according to the protocol of the National Phosphorus Research Project (NPRP, 2001). P from a composite of twenty‐four 2.0‐cm‐diameter core soil samples (0–5 cm) was extracted using the Olsen, Bray–Kurtz, Mehlich III, distilled water and 0.01 m calcium chloride procedures. All of these P extraction methods explained a significant amount of variability in surface run‐off total dissolved P [TP (<0.45)] ( r 2 ≥ 0.67; P ≤ 0.01), where 0.45 is the filter pore diameter in microns. Multiple regression models showed extractable P to be the best soil predictor of surface run‐off TP (<0.45) among the studied soils. Despite extraction method or soil type, extractable P was the best soil predictor of surface run‐off TP (<0.45). Either agronomic (0.92 ≤ r 2 ≤ 0.96) or environmental (0.94 ≤ r 2 ≤ 0.96) soil tests were effective in estimating surface run‐off TP (<0.45) in select Mollisols.