Use this URL to cite or link to this record in EThOS:
Title: N2O emission and inorganic N release following combined application of crop residues and inorganic N fertiliser into soil
Author: Frimpong, Kwame Agyei
ISNI:       0000 0004 2709 6065
Awarding Body: University of Aberdeen
Current Institution: University of Aberdeen
Date of Award: 2010
Availability of Full Text:
Access from EThOS:
Experiments were conducted at the University of Aberdeen under controlled laboratory conditions to examine the interactive effect of combining crop residues barley (Hordeum vulgare), clover (Trifolium pretense), cowpea (Vigna unguiculata), Leucaena (Leucena leucocephala) and Mucuna (Mucuna pruriens) and inorganic N fertiliser on N2O emission and mineral N dynamics. Emissions of N2O increased following sole application of the residues dependent on their utility or chemical composition. In general emissions were significantly higher from soils amended with low C:N ratio clover, cowpea, Leucena and Mucuna residues compared to the high C:N ratio barley species. N2O emission was further increased following combined application of crop residues and inorganic N fertiliser but the magnitude of emission was influenced by the proportional ratios at which the residue-N and the fertiliser-N were combined, and the C:N ratio, lignin and polyphenols contents of the residues, with the low lignin and low polyphenols cowpea treatment emitting higher N2O over 30 days compared to the high lignin Mucuna and the  high polyphenols Leucena treatments. Results from experiments demonstrated that whilst there is the potential for N2O emission to be controlled through varying ratios of residue:fertiliser input, the magnitude and direction of interactions between these N sources varies between different species as a result of their differing qualities. Based on our applications of Leucaena, Mucuna and cowpea residues, the 75:25 residue: fertiliser ratio at 100 mg N kg-1 soil is recommended from this study as offering the best compromise between release of N for crop uptake and management of N2O emission, but this requires further investigation at field scale.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available