Wednesday 17 of April 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)
Studying the impacts of climate change and ocean acidification on calcified macroalgae: why, how and what we have we found
Chris Williamson
Genomics & Microbes, Dept of Life Sciences, NHM and School of Earth and Ocean Sciences, Cardiff University
Climate change and ocean acidification (OA) are causing increased sea surface temperatures and decreased pH / carbonate saturation, respectively, in the marine environment. Almost all marine species are likely to be impacted in some respect by these changes, with calcifying species predicted to be the most vulnerable. Calcifying macroalgae of the red algal genusCorallina are widely distributed and important autogenic ecosystem engineers, providing habitat for numerous small invertebrate species, shelter from the stresses of intertidal life, and surfaces for the settlement of microphytobenthos. Given the particular skeletal mineralogy of these species, i.e. high Mg-calcite CaCO3, they are predicted to be among the first responders to OA. A research project is therefore being undertaken to examine the potential impacts of climate change and OA on Corallina species in the northeastern Atlantic. An approach has been adopted to allow examination of potential impacts in the context of present day and very recent past conditions. This seminar will present information on the approach employed (use of herbarium collections, seasonal northeastern Atlantic sampling), methodologies used (X-Ray Diffraction, PAM-fluorescence, SEM, molecular techniques), and results gained thus far (seasonal skeletal mineralogy cycles, carbonate chemistry experienced in situ, photophysiology). Plans for the next stage of the project (future scenario incubations) will also be presented, highlighting how lessons learnt thus far will inform this future work.
Friday 19 of April 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)
Forest understorey plant dynamics in the face of global environmental change
Pieter De Frenne
Forest & Nature Lab, Department of Forest and Water Management, Ghent University
Habitat change, eutrophication and climate change, among other global-change factors, have elevated the rate of species’ extinction to a level on par with historical mass extinction events. In temperate forests specifically, biodiversity is mainly a function of the herbaceous understorey community. Many forest understorey plants, however, are not able to track habitat change and the shifting climate due to their limited colonisation capacity. Their acclimation potential within their occupied habitats will likely determine their short- and long-term persistence. The response of plants to N deposition, however, diverges between forests and other ecosystems, probably due to the greater structural complexity and pivotal role of light availability in forests. A potential new pressure on forest biodiversity is the increasing demand for woody biomass due to the transitions to more biobased economies. Elevated wood extraction could result in increased canopy opening and understorey species shifts. To date, the outcome of climate warming and changing forest management (resulting in altered light availability) in forests experiencing decades of elevated N inputs remains uncertain. I will present our research on the (interactive) effects of climate warming, enhanced N inputs, and management-driven forest floor light availability on the growth and reproduction of a selection of understorey forest plant species, and (ii) the composition and diversity of understorey plant communities in European and eastern North American temperate forests.
For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html