Flooding tolerance of four floodplain meadow species depends on age

Abstract

Numerous restoration campaigns focused on re-establishing species-rich floodplain meadows of Central Europe, whose species composition is essentially controlled by regular flooding. Climate change predictions expect strong alterations on the discharge regime of Europe’s large rivers with little-known consequences on floodplain meadow plants.In this study, we aim to determine the effects of flooding on seedlings of different ages of four typical flood meadow species. To this end, we flooded seedlings of two familial pairs of flood meadow species of wetter and dryer microhabitats for 2 weeks each, starting 2, 4, 6, and 8 weeks after seedling germination, respectively.We show that a 2-week-flooding treatment had a negative effect on performance of seedlings younger than 6 weeks. Summer floods with high floodwater temperatures may have especially detrimental effects on seedlings, which is corroborated by previous findings. As expected, the plants from wet floodplain meadow microhabitats coped better with the flooding treatment than those from dryer microhabitats.In conclusion, our results suggest that restoration measures may perform more successfully if seedlings of restored species are older than the critical age of about 6 weeks before a spring flooding begins. Seasonal flow patterns may influence vegetation dynamics of floodplain meadows and should, therefore, be taken into account when timing future restoration campaigns.

Ecological responses to heavy rainfall depend on seasonal timing and multi‐year recurrence

“…It has been suggested that higher‐diversity communities are less negatively affected by floods and that some grasses are unaffected by floods regardless of plant diversity (Wright et al ., ). Furthermore, mature plants may tolerate flooding better than young plants (Gattringer et al ., ).…”

Modelling of rare flood meadow species distribution by a combined habitat surface water–groundwater model

“…These predictors are based on various experimental studies (e.g., Gattringer et al, 2017;Gattringer, Ludewig, Harvolk-Schöning, Donath, & Otte, 2018;Van Eck, Van De Steeg, Blom, & De Kroon, 2004) or observational studies (e.g., Leyer, 2005;Mosner et al, 2015). These predictors are based on various experimental studies (e.g., Gattringer et al, 2017;Gattringer, Ludewig, Harvolk-Schöning, Donath, & Otte, 2018;Van Eck, Van De Steeg, Blom, & De Kroon, 2004) or observational studies (e.g., Leyer, 2005;Mosner et al, 2015).…”

“…For each vegetation plot, we generated 81 hydrological predictors (Appendix S2). These predictors are based on various experimental studies (e.g., Gattringer et al, 2017;Gattringer, Ludewig, Harvolk-Schöning, Donath, & Otte, 2018;Van Eck, Van De Steeg, Blom, & De Kroon, 2004) or observational studies (e.g., Leyer, 2005;Mosner et al, 2015). We derived the hydrological predictors either for the entire year or only for the vegetation period, and we considered up to 6 years before the monitoring year, thus resulting in n = 14 different variations.…”

“…These measures primarily focus on the reestablishment of rare, often highly specialized species with complex habitat requirements (Donath, Bissels, Hölzel, & Otte, 2007;Engst et al, 2016). Thus, hydrological conditions should be incorporated in the planning of flood meadow restoration projects (Gattringer et al, 2017). Plant distribution is strongly related to hydrological conditions, for example, flood sensitive species occupy elevated microsites, whereas flood-tolerant species occur in depressions (V. Jung, Hoffmann, & Muller, 2008;Ludewig et al, 2014;Vervuren, Blom, & De Kroon, 2003).…”

“…Plant distribution is strongly related to hydrological conditions, for example, flood sensitive species occupy elevated microsites, whereas flood-tolerant species occur in depressions (V. Jung, Hoffmann, & Muller, 2008;Ludewig et al, 2014;Vervuren, Blom, & De Kroon, 2003). Thus, hydrological conditions should be incorporated in the planning of flood meadow restoration projects (Gattringer et al, 2017).…”