Plant community dynamics and carbon sequestration in Sphagnum-dominated peatlands in the era of global change

Hydroclimatic shift and anthropogenic-driven nitrogen deposition are major outcomes of global change that could compromise the functioning of many peatlands as a carbon sink. For Sphagnum-dominated peatlands, an emerging hypothesis is that the change could be triggered by shifts in competitive dominance among plant functional groups, specifically from the dominant decay-resistant Sphagnum to the more decomposable vascular plants. However, the relationship between Sphagnum and vascular plant occurrence is notably complex and also includes facilitative interactions that are crucial to the productivity of Sphagnum and therefore carbon sequestration. We use a conceptual review to examine underlying mechanisms for the competitive exclusion hypothesis and the nature of facilitative interactions between Sphagnum and vascular plants under the potential global change conditions. We supported the review with a field study conducted at Luther Marsh conservation area where we quantified, hummock dimensions, light penetration , C:N, hummock moisture profile etc between two hydrologically contrasting sites.