Microbial nitrogen dynamics in organic and mineral soil horizons along a latitudinal transect in western Siberia.

ABSTRACT: Soil N availability is constrained by the breakdown of N-containing polymers such as proteins to oligopeptides and amino acids that can be taken up by plants and microorganisms. Excess N is released from microbial cells as ammonium (N mineralization), which in turn can serve as substrate for nitrification. According to stoichiometric theory, N mineralization and nitrification are expected to increase in relation to protein depolymerization with decreasing N limitation, and thus from higher to lower latitudes and from topsoils to subsoils. To test these hypotheses, we compared gross rates of protein depolymerization, N mineralization and nitrification (determined using ¹⁵N pool dilution assays) in organic topsoil, mineral topsoil, and mineral subsoil of seven ecosystems along a l

SUBMITTER: Wild B 

PROVIDER: S-EPMC4676305 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature