Extreme climate events and wetlands

Extreme climate events are those defined by great magnitude over short temporal scales that may cause profound ecosystem responses. They include intense precipitation and extreme temperatures, and consequent floods, heat waves and droughts.

Extremes are of particular interest because research has tended to focus on steady change scenarios, yet ecosystem responses are often disproportionately greater under extreme events. Globally, extreme climate events are expected to become more frequent and increase in intensity and duration. Wetlands may mediate climate change impacts through their multiple ecosystem services, but the mechanisms for any resilience are not well known.

In partnership with the RSPB, Natural England and the Sussex Wildlife Trust, this project, led by Professor Chris Joyce, identified wetland responses and adaptations to extreme climate events in order to develop knowledge for future wetlands. It focused upon wet grasslands as particularly valuable and potentially sensitive wetland types.

The project aims to address three key questions:

> How do wetlands respond to climate events?
> Can wetlands and the species in wetlands adapt to climate extremes and, if so, what are the mechanisms that enable their survival?
> How can humans use knowledge of current species and functional responses in wetlands to proactively create, restore and manage wetlands for the future?

The project integrated field-based studies on globally important wetlands in Sussex, England, with mesocosm experiments at the university’s Wetland Ecology Research Facility.

In the field, studies at Amberley Wildbrooks in West Sussex examined the effects of extreme hydrological change on floodplain grassland indicator plant species. Water level monitoring is helping understand baseline hydrological characteristics in contrasting wetland types representing future ‘dry’ and ‘wet’ scenarios. Mesocosm experiments are investigating the role of plant competition in facilitating survival to extreme flood events. The field and mesocosm research both used a plant trait approach to examine physiological and phenological effects of extreme events.

Selected publications

Brotherton, SJ and Joyce, CB (2014) Extreme climate events and wet grasslands: plant traits for ecological resilience. Hydrobiologia. DOI 10.1007/s10750-014-2129-5

Berg, M., Joyce, C.B. and Burnside, N. (2012) Differential responses of abandoned wet grassland plant communities to reinstated cutting management. Hydrobiologia, 692, 83-97