Linking Restoration and Ecological Succession (Springer ... - Inecol

102 Joachim Schrautzer et al.
Figure 5.6 Rewetted wet pastures, dominated by tall sedge reeds with Carex acutiformis
and Phalaris arundinacea in Pohnsdorfer Stauung near Kiel, Germany.
in all seres, stage IV was the highest N source, and also had the highest denitrification
values. N leaching in seres A and B increased from stage I to IV, but in
sere C (wet eutrophic meadows 4B) N-leaching was highest in stage I. All seres
showed a shift in C-balance from a carbon source (sedges/meadows/pastures)
to a carbon sink (carrs). In all stages, the efficiency measures were highest in
stage 4.
5.3.3 Change of Ecosystem Features After Rewetting
The development from intensively drained wet pastures (5) to eutrophic tall
sedge reeds (2B) after rewetting (Fig. 5.6) resulted in a decrease of species
richness (Fig. 5.5). However, species richness increased in the long run if the tall
sedge reeds sere developed into eutrophic alder carrs (1B). Rewetting also led
to a distinct decrease of NNM, N-leaching, denitrification rates, and microbial
soil respiration (MSR). Furthermore, ecosystems changed from high to low
nitrogen sources and from high to low carbon sources or carbon sinks. Values
of efficiency measures (NPP/MSR, NPP/transpiration) were enhanced during
succession after rewetting (Fig. 5.5).
5.3.4 Relationships Between Vegetation Structure, Plant Traits,
and Species Groups
In stands of the abandonment fens the RI at 30 cm height decreased significantly
with increasing standing crop (r = 0.81; p < 0.001). This was reflected
in a positive correlation between the number of small-growing species
and light availability (r = 0.73; p < 0.001) across the stages. Most of the
Scheuchzerio-Caricetea species are small, whereas species of the Phragmitetea,