Modelling Tipping Points

What are tipping points?

Tipping points are those critical events, either strong (extreme weather events) or seemingly mild (shift of currents or variation of seawater vs. saltwater input), that can cause a shift in ecosystems structure, extent and service provisioning. By their nature, mangroves are highly laterally dynamic over short time periods when exceeding tipping points. Social vulnerability, extreme weather events and sea level rise are factors that can contribute to such tipping points, changing ecosystem features and thus their service provisioning.

Exceeding tipping points can cause either gain or loss in mangrove extent. This makes understanding the drivers and modelling these tipping points, key to enable a healthy mangrove ecosystem and realise the economic value linked to such dynamics, separating long- and short-term spatio-temporal processes.

Erosion at the Xuan Thuy National Park channels

Colonization mudflats at Xuan Thuy National Park

Sediment accretion in Xuan Thuy National Park


Modelling tipping points

MOMENTS is developing, for the first time, a fully parameterized mechanistic model predicting mangrove seedling establishment and failure of trees in an active sedimentary environment. This requires experimentally testing Windows of Opportunity (WoO), a period free of any disturbance that allows seedlings to grow their first roots and firmly anchor to the sediment. Knowing species specific WoO will help identify species and areas or time-periods where seedlings have a greater chance of survival. This knowledge will be a valuable tool for aiding the planning of restoration efforts.
Moreover, MOMENTS studies the magnitude of erosion that can cause larger trees to fail and topple. These experimentally tested thresholds, combined with field data, will feed a mechanistic model that will help understand and predict critical thresholds of mangrove change, which, complemented with remote sensing information, will aid the assessment and forecast of forest extent and valuation of associated ecosystem service provision.

Mesocosms greenhouse in the Uiversity of Smatera Utara, Medan

Erosion experiment at the Xuan Thuy National Park, Vietnam