Pollen-vegetation relationships in Bay of Fundy salt marshes

We examined the distribution of vegetation and pollen in surface soils of three salt marshes on the outer Bay of Fundy to assess the value of pollen in paleoenvironmental reconstructions. We examined the relationship of pollen to vegetation using linear regression at two scales: vegetation zones dominated by graminoids and forb patches within these zones. Of the dominant graminoids, only pollen of Cyperaceae was a dependable indicator of source vegetation. In contrast, at least seven common forbs were significantly represented by their pollen at one or both scales. Because forbs are more abundant in northern marshes, increases in forb pollen abundance in buried sediments of southern marshes could signal colder climate regimes. Other studies have shown Plantago maritima L. and Ligusticum scoti cum L. to be associated with distinct ranges in elevation, and Triglochin maritima L. with soil anoxia. Thus, shifts in forb pollen abundance may indicate changes in tidal flooding frequency and sea levels.