| Publication Details | 
| Category | Text Publication | 
| Reference Category | Journals | 
| DOI | 10.1007/s10533-004-5733-z | 
| Document | Shareable Link | 
| Title (Primary) | Losses and biogeochemical cycling of soil organic nitrogen with prolonged arable cropping in the South African Highveld - evidence from D- and L-amino acids | 
| Author | Brodowski, S.; Amelung, W.; Lobe, I.; Du Preez, C.C. | 
| Source Titel | Biogeochemistry | 
| Year | 2004 | 
| Department | FLOEK | 
| Volume | 71 | 
| Issue | 1 | 
| Page From | 17 | 
| Page To | 42 | 
| Language | englisch | 
| Abstract | We know little about the mechanisms that cause rapid losses in the soil organic N pool during cropping. As the analysis of amino acid enantiomers can provide insight into both the fate of microbial N and the ageing of cells in the environment, we used this technique as a tool to examine how the pool of protein-bound N in subtropical Plinthosols responds to increasing duration of arable cropping. The samples comprised bulk soils (0–20 cm) and clay fractions from each of three agro-ecosystems in semiarid South Africa; the sites have been cropped for periods varying from 0 to 98 years. The amino acid enantiomers contributed 34% to the total N content. With increasing number of years a piece of land has been cropped, the amino acid concentrations declined bi-exponentially to about 30% of their initial level in the native grasslands. Changes of the remaining soil protein-N pool were indicated by alterations in the -content of individual amino acids. As the years of arable cropping increased, the proportions of -alanine and -glutamic acid increased relative to the respective -enantiomers. This was attributed to an accumulation of N in residues of bacterial cell walls. In contrast, the /-ratios of leucine and aspartic acid declined in the long-term cultivated plots, probably reflecting losses of old amino acid-N reserves at the most degraded arable land. | 
| Persistent UFZ Identifier | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=4012 | 
| Brodowski, S., Amelung, W., Lobe, I., Du Preez, C.C. (2004): Losses and biogeochemical cycling of soil organic nitrogen with prolonged arable cropping in the South African Highveld - evidence from D- and L-amino acids Biogeochemistry 71 (1), 17 - 42 10.1007/s10533-004-5733-z | |
