Time and heat for sexual reproduction: comparing the phenology of Chara hispida of two populations at different latitudes

Abstract Geographical location affects the main ecological factors driving the timing of plants’ life events. In addition, studying phenology is the simplest procedure to track current global warming and its effects on the success and survival of different populations of the same species. Little is known about the effect of water temperature and its corresponding accumulated heat on charophytes’ phenology. We compared differences in water temperature and sexual reproductive phenology of Chara hispida in two ponds of two countries located at different latitudes (Spain and Switzerland) over the same year. We estimated the accumulated heat required to develop from one phenophase to another (un…

Shifts in plankton assemblages promoted by free water surface constructed wetlands and their implications in eutrophication remediation

Abstract Two units of free water surface constructed wetlands (FWSCWs) were created in 2009 in a Mediterranean protected site, the Albufera de Valencia Natural Park, to treat eutrophic inflows to the Albufera de Valencia lagoon, the largest coastal lagoon in the Iberian Peninsula, affected by cultural eutrophication. Data of phytoplankton and zooplankton biomass and richness of the inflows and outflows corresponding to the first 3.5 years of operation of the system have been analyzed to evaluate the role of plankton in the eutrophication reversion. The FWSCWs significantly reduced the exported microalgal biomass, stimulated the potential mixotrophic groups of phytoplankton such as Euglenoph…

Different responses of coexisting Chara species to foreseeable Mediterranean temperature and salinity increases

Abstract An increase in temperature of approximately 4 °C is expected to occur in the Mediterranean by the end of the century. Concomitant to this warming, a foreseeable rise in salinity will affect aquatic species. We addressed the effects of warming and salinity, and their interaction on three coexisting characean species (Chara aspera, C. hispida and C. vulgaris) from a Spanish Mediterranean interdunal pond (spring water temperature 20–23 °C, when charophytes re-grew; salinity 1.3–1.8 PSU). A laboratory experiment was designed with two levels of water temperature treatment (23 and 27 °C), plus two levels of salinity treatment (0.4 and 4.0 PSU). The variables considered were total length,…

Persistence of submerged macrophytes in a drying world: Unravelling the timing and the environmental drivers to produce drought-resistant propagules

Reproductive phenology of submerged macrophytes: A tracker of year‐to‐year environmental variations

AIMS: Phenological shifts are useful trackers of climate change effects on species and communities, but few datasets focus on the climate‐driven phenological responses of aquatic ecosystem vegetation. We aimed to analyse the reproductive seasonality of a submerged macrophyte community, the synchrony among coexisting species, and their responses to several environmental factors. LOCATION: A Mediterranean coastal pond in Valencia, Spain. METHODS: We analysed three years of data on a submerged macrophyte community. Plants were collected biweekly or monthly (57 collection dates) to quantify the intensity of flowering/fruiting per species. The reproductive seasonality of the community was tested…

Germination capability of four charophyte populations (Characeae) from Mediterranean brackish ponds under warm experimental conditions

ABSTRACTThe diaspore banks from two brackish ponds within the Albufera de Valencia Natural Park (Spain) containing oospores of Chara hispida, C. aspera, C. canescens and Nitella hyalina were analys...