Till startsida
Webbkarta
Till innehåll Läs mer om hur kakor används på gu.se

Microbial utilization of mineral-associated nitrogen in soils

Artikel i vetenskaplig tidskrift
Författare Stephanie Turner
Sandra Meyer-Stüve
Axel Schippers
Georg Guggenberger
Frank Schaarschmidt
Birgit Wild
Andreas Richter
Reiner Dohrmann
Robert Mikutta
Publicerad i Soil Biology and Biochemistry
Volym 104
Sidor 185-196
ISSN 0038-0717
Publiceringsår 2017
Publicerad vid Institutionen för geovetenskaper
Sidor 185-196
Språk en
Länkar dx.doi.org/10.1016/j.soilbio.2016.1...
Ämnesord Microbial nitrogen cycling; Quantitative PCR; Net N mineralization; Functional genes; Mineral-associated organic matter; Priming
Ämneskategorier Terrestrisk ekologi

Sammanfattning

In soils, a large portion of organic nitrogen (ON) is associated with minerals and thus, possibly stabilized against biological decay. We therefore tested if mineral-associated N is an important N source for soil microorganisms, and which soil parameters control its bioavailability. Microcosm experiments with mineral-associated organic matter, obtained as heavy fraction (HF) via density fractionation, and bulk soil from mineral topsoil of the Franz Josef chronosequence were conducted for 125 days. We examined the effects of O2 status, soil age (differences in mineralogical properties), as well as cellulose and phosphate additions on the turnover of mineral-associated N. Using a combination of activity measurements and quantitative PCR, microbial N transformation rates and abundances of N-related functional genes (amoA, narG, chiA) were determined. Similar or higher values for microbial N cycling rates and N-related functional abundances in the HF compared to bulk soil indicated that mineral-associated N provides an important bioavailable N source for soil microorganism. The turnover of mineral-associated N was mainly controlled by the O2 status. Besides, soil mineralogical properties significantly affected microbial N cycling and related gene abundances with the effect depending on the N substrate type (ON, NH4+ or NO3−). In contrast, cellulose or phosphate addition hardly enhanced microbial utilization of mineral-associated N. The results of our microcosm study indicate that mineral-associated N is highly bioavailable in mineral topsoils, but effects of the mineral phase differ between N cycling processes.

Sidansvarig: Webbredaktion|Sidan uppdaterades: 2012-09-11
Dela:

På Göteborgs universitet använder vi kakor (cookies) för att webbplatsen ska fungera på ett bra sätt för dig. Genom att surfa vidare godkänner du att vi använder kakor.  Vad är kakor?