Effects of filter type and extraction efficiency on nitrogen mineralization measurements using the aerobic leaching soil incubation method
Abstract
Aerobic incubation of soils with sequential leachings to extract mineralized N is often used to determine N mineralization potential and N availability in the laboratory. This study used tropical forest soils with differing mineralogy and texture to address: (1) the effects of filter type and equilibration time on soil moisture and N mineralization and (2) the N extraction efficiency of 0.01 M CaCl2, minus-N nutrient solution (containing 0.004 M CaCl2) and 2 M KCl. Use of glass microfiber filters compared to cellulose acetate or polyethersulfone membrane filters resulted in a lower moisture content for both low-and high-clay soils. However, filter type did not affect N mineralization. Under 47 kPa suction, soil moisture equilibration occurred between 240 and 360 min regardless of filter type. Extraction efficiency for mineralized N using 0.01 M CaCl2 or minus-N nutrient solution was lower in forest soils of smectitic mineralogy and soils with a higher proportion of macroaggregates. However, with the exception of allophanic soils, the cumulative amount of N mineralized measured in a long-term incubation for approximately 1 year was not different when either a leaching or an unleached incubation method was used. These results indicate that researchers may wish to conduct preliminary evaluations to determine whether their incubation method will achieve a desired uniform moisture level and N extraction efficiency.
Department
Soil Biogeochemistry and Microbial Ecology
Publication Date
8-1-1995
Journal Title
Biology and Fertility of Soils
Publisher
Springer
Digital Object Identifier (DOI)
Document Type
Article
Recommended Citation
Motavalli, P.P., Frey, S.D. & Scott, N.A. Effects of filter type and extraction efficiency on nitrogen mineralization measurements using the aerobic leaching soil incubation method. Biol Fertil Soils 20, 197–204 (1995). https://doi.org/10.1007/BF00336558