MSI99P3291 | |
Paul, J. P. | |
University of Aberdeen, Faculty of Science, Scotland | |
Characteristics of dissolved organic nitrogen extracted from soils | |
Thesis, MSc Analytical Chemistry | |
Thesis | |
1999 | |
72 p.: 8 figs, 17 tbls, 2 pl., 3 appen. | |
En | |
En | |
A preliminary attempt has been undertaken to characterise the soluble fraction of soil N with particular emphasis on the organic fraction, using simple photometric methods. To do this, a factorial experiment was carried out. Three organic Scottish soils (surface 10 cm) were extracted for N using two different techniques (leaching and shaking), and four extracting solutions (distilled-deionised water, 0.01M CaCl2,, 0.05 M NaH2PO4 and 0.05 M K2SO4). The dissolved organic nitrogen (DON) was dependent on all the factors investigated, and the interaction between the soil and the extracting solution was highly significant (P less than 0.001). The -amino- and peptide-N was on average 3-26 per cent and 36-56 per cent of the DON respectively. The free amino-N content of the soil was inversely proportional to the microbial activity being higher in peat soil compared to mineral soil with a high organic matter content. Free glutamic acid predominated in the soil analysed. The effects of added mineral N as 15NH4 15NO3 on soil DON were also investigated and they were soil dependent. The mineral N added had little efect on the soil biomass nitrogen. | |
SOILS ORGANIC NITROGEN CHARACTERIZATION AMINO ACIDS | |
Soils and plant nutrition | |
Nitrogen | |
22-11-99 | |
En | |
MSIRI | |
List | |
CHEM |