Bray‐2 phosphorus as influenced by soil fineness and filtration time

摘要: Abstract Fine soil with a particle size less than 2 mm is generally used when determining Bray‐2 phosphorus (P). The average aggregate varies widely in the fine of structural soils and may influence reproducibility at extractions. Our objective was to study how this variation fineness related filtering time jointly P values three different types then propose corrective measures improve extraction. In an Ultisol, there no difference between sieved through 1‐mm mesh compared 0.2‐mm mesh. drastically decreased (less 0.2 mm) allophanic Andisols passed disappeared gradually, extending extraction from method specific for 40 or 60 seconds not observed 3 min longer. finer structure delayed filter papers...