Refine
Year of publication
- 2012 (1)
Document Type
- Article (1)
Language
- English (1)
Has Fulltext
- no (1)
Is part of the Bibliography
- yes (1)
Keywords
- functional type (1) (remove)
Institute
- Fakultät AuL (1)
15 δ N signals in plant and soil material integrate over a number of biogeochemical processes
related to nitrogen (N) and therefore provide information on net effects of multiple
processes on N dynamics. In general little is known in many grassland restoration projects
on soil–plant N dynamics in relation to the restoration treatments. In particular, 15 δ N signals
may be a useful tool to assess whether abiotic restoration treatments have produced the
desired result. In this study we used the range of abiotic and biotic conditions provided
by a restoration experiment to assess to whether the restoration treatments and/or plant
functional identity and legume neighborhood affected plant 15 δ N signals. The restoration
treatments consisted of hay transfer and topsoil removal, thus representing increasing
restoration effort, from no restoration measures, through biotic manipulation to major
abiotic manipulation. We measured 15 δ N and %N in six different plant species (two nonlegumes and four legumes) across the restoration treatments. We found that restoration
treatments were clearly reflected in 15 δ N of the non-legume species, with very depleted
15 δ N associated with low soil N, and our results suggest this may be linked to uptake of
ammonium (rather than nitrate). The two non-legume species differed considerably in their
15 δ N signals, which may be related to the two species forming different kinds of mycorrhizal
symbioses. Plant 15 δ N signals could clearly separate legumes from non-legumes, but our
results did not allow for an assessment of legume neighborhood effects on non-legume
15 δ N signals. We discuss our results in the light of what the 15 δ N signals may be telling
us about plant–soil N dynamics and their potential value as an indicator for N dynamics in
restoration.