Long‐term Reactions of Plants and Macroinvertebrates to Extreme Floods in Floodplain Grasslands

Abstract

Extreme summertime flood events are expected to become more frequent in European rivers due to climate change. In temperate areas, where winter floods are common, extreme floods occurring in summer, a period of high physiological activity, may seriously impact floodplain ecosystems. Here we report on the effects of the 2002 extreme summer flood on flora and fauna of the riverine grasslands of the Middle Elbe (Germany), comparing pre- and post-flooding data collected by identical methods. Plants, mollusks, and carabid beetles differed considerably in their response in terms of abundance and diversity. Plants and mollusks, displaying morphological and behavioral adaptations to flooding, showed higher survival rates than the carabid beetles, the adaptation strategies of which were mainly linked to life history. Our results illustrate the complexity of responses of floodplain organisms to extreme flood events. They demonstrate that the efficiency of resistance and resilience strategies is widely dependent on the mode of adaptation.

Extreme climate events and wet grasslands: plant traits for ecological resilience

“…Wetlands are underrepresented, although field studies on actual high magnitude flood events have been published for floodplain grasslands (e.g. Vervuren et al, 2003;Ilg et al, 2008) and indicate mixed impacts upon biodiversity. The effects of extreme droughts have also been studied in the field, especially on woodland or shrub communities (Valladares & Niinemets, 2008;Cavin et al, 2013;Herrero & Zamora, 2014), and Koyama & Tsuyuzaki (2013) studied seedlings of perennial herbs in a peatland affected by extreme drought.…”

“…Less flood tolerant species can show reduced distribution for many years following extreme flooding in contrast to more flood tolerant riparian species (Vervuren et al, 2003). However, vegetation abundance on floodplains does not necessarily significantly decrease after extreme flooding (Sparks et al, 1990), although diversity and species turnover can be immediately affected (Ilg et al, 2008). This suggests that stability is determined by long-term processes allowing the community to remain functional through species turnover.…”

The role of an extreme flood disturbance on macrophyte assemblages in a Neotropical floodplain

“…These factors interact and their effects should not be viewed separately (van Geest et al 2003). However, except for lakes not inundated during the growing season (van Geest et al 2003), the hydrological regime is considered to be the main driving force that determines the structure of several types of aquatic assemblages (Junk et al 1989;Neiff 1990;Ilg et al 2008), including macrophyte assemblages (Bornette et al 1994(Bornette et al , 2001Reid and Quinn 2004;Maltchik et al 2007;Strausz and Janauer 2007). Vegetation response to floods basically results from nutrient and propagule inputs, scouring effects, suspended matter inputs and depositional processes (Bornette et al 2008).…”

Effects of species turnover on reserve site selection in a fragmented landscape

“…Landscapes with rapid natural succession, such as many agricultural landscapes, fire prone landscapes (Caughley 1985;Kleyer et al 2007), or floodplain systems (Stelter et al 1997;Ilg et al 2008), also frequently show hyperdynamism. Spatial shifts of activity within fragments might also have contributed to the turnover but the apparent shifts in species composition frequently involved frog species for which high local survival during the active season within a year could be demonstrated (Steinicke 2008).…”