Back to Search
Start Over
Alleviation of Plant Stress Precedes Termination of Rich Fen Stages in Peat Profiles of Lowland Mires
- Source :
- Ecosystems. 23:730-740
- Publication Year :
- 2019
- Publisher :
- Springer Science and Business Media LLC, 2019.
-
Abstract
- Mesotrophic rich fens, that is, groundwater-fed mires, may be long-lasting, as well as transient ecosystems, displaced in time by poor fens, bogs, forests or eutrophic reeds. We hypothesized that fen stability is controlled by plant stress caused by waterlogging with calcium-rich and nutrient-poor groundwater, which limits expansion of hummock mosses, tussock sedges and trees. We analysed 32 European Holocene macrofossil profiles of rich fens using plant functional traits (PFTs) which indicate the level of plant stress in the environment: canopy height, clonal spread, diaspore mass, specific leaf area, leaf dry matter content, Ellenberg moisture value, hummock-forming ability, mycorrhizal status and plant functional groups. Six PFTs, which formed long-term significant trends during mire development, were compiled as rich fen stress indicator (RFSI). We found that RFSI values at the start of fen development were correlated with the thickness of subsequently accumulated rich fen peat. RFSI declined in fens approaching change into another mire type, regardless whether it was shifting into bog, forest or eutrophic reeds. RFSI remained comparatively high and stable in three rich fens, which have not terminated naturally until present times. By applying PFT analysis to macrofossil data, we demonstrated that fens may undergo a gradual autogenic process, which lowers the ecosystem’s resistance and enhances shifts to other mire types. Long-lasting rich fens, documented by deep peat deposits, are rare. Because autogenic processes tend to alleviate stress in fens, high levels of stress are needed at initial stages of rich fen development to enable its long persistence and continuous peat accumulation.
- Subjects :
- 0106 biological sciences
geography
geography.geographical_feature_category
Peat
010504 meteorology & atmospheric sciences
Ecology
Specific leaf area
Tussock
Macrofossil
Waterlogging (archaeology)
010603 evolutionary biology
01 natural sciences
Mire
Environmental Chemistry
Environmental science
Eutrophication
Bog
Ecology, Evolution, Behavior and Systematics
0105 earth and related environmental sciences
Subjects
Details
- ISSN :
- 14350629 and 14329840
- Volume :
- 23
- Database :
- OpenAIRE
- Journal :
- Ecosystems
- Accession number :
- edsair.doi...........41b274b73f53253512ba6fe38b124e9f