The relationship between Bray's P1, modified NaHCO3, New Mehlich and NH4F. HF extractants for P in savannah soils of western Nigeria
Olufemi Ayodele; Akinola Agboola
Nutrient Cycling in Agroecosystems 2(2): 89-99
ISSN/ISBN: 1385-1314 DOI: 10.1007/bf01080095
Sixty surface (0-15 cm) soil samples and 20 field sites with different cropping histories were selected from the major soil types of the western Nigeria basement complex savannah. Available P was evaluated with six extractants, namely Bray's P1, 0.1N AHDF (pH 4.1-4.3), 0.1N AHDF (pH 5.0), 0.05N AHDF (pH 7.0), New Mehlich and modified Olsen's 0.5M NaHCO3 (pH 8.5). The greatest amount of P was extracted by 0.1N AHDF (pH 4.1-4.3), while 0.05N AHDF (pH 7.0), extracted the least.