vbid/9783030310578

Description

This book presents innovative research on soil nitrogen cycling and nitrate leaching with a view to improving soil management and fertiliser nitrogen use efficiency and reducing nitrogen leaching losses. In this regard, nitrogen-15 (15N)-labelled fertiliser was used as a biochemical and physical stable isotope tracer in laboratory and field experiments. The major outcome of the research was the development, validation and application of a new compound-specific amino acid 15N stable isotope probing method for assessing the assimilation of fertiliser nitrogen by soil microbial biomass.�The novelty of the method lies in its tracing of incorporated nitrogen into newly biosynthesised microbial protein in time-course experiments using gas chromatography-combustion-isotope ratio mass spectrometry. The approach provides previously unattainable insights into the microbial processing of different nitrogen fertilisers in different soils. Further, it identifies the mechanistic link between molecular-scale processes and observations of field-scale fertiliser nitrogen immobilisation studies. The method and the results presented here will have far-reaching implications for the development of enhanced recommendations concerning farm-based soil management practices for increasing soil productivity and reducing nitrogen losses, which is essential to minimising environmental impacts.Typham this is the title: 15N Tracing of Microbial Assimilation, Partitioning and Transport of Fertilisers in Grassland Soils