Pollen and plant macrofossils are often well-preserved in coastal sediments, providing a palaeoenvironmental record of sea-level and landscape change. In this study, we examine the pollen and plant macrofossil assemblages of a well-dated saltmarsh sediment core from southwest Newfoundland, Canada, to establish recent coastal vegetation and land use change, to increase the knowledge of anthropogenic activities in the area and develop pollen chronozones for reconstructing marsh accumulation rates and to examine the representation of plant macrofossil remains in the wetland pollen profile. Grouping the pollen record into upland and wetland assemblages allows local events related to hydrological change to be separated from landscape-scale changes. The wetland pollen and plant macrofossil records indicate a general acceleration in sea-level rise ca. ad 1700. The sedge pollen and plant macrofossil records attest to multiple phases of rhizome encroachment during inferred periods of marine regression. Two chronozones are identified from the upland pollen profile; the first associated with the settlement of St. George’s Bay ca. ad 1800, signalled by increases in Plantago lanceolata and Ambrosia pollen; the second with the permanent settlement of the Port au Port peninsula ca. ad 1850, indicated by increased P. lanceolata and Rumex pollen. Comparison of the plant macrofossil and wetland pollen profiles highlights the underrepresentation of grass pollen preserved in the saltmarsh sediments and a need for further analysis of the zonation, pollen dispersal and macrofossil representation of sedge species in saltmarshes.
Phases of rapid climate change throughout the early to mid Holocene coincide with regional human population expansion in Scotland and North-West Europe. Palaeoenvironmental signals of climate and anthropogenically driven vegetation changes can therefore be difficult to separate. To identify whether it is possible to distinguish potential signatures of anthropogenic clearance and agricultural activities from climatic drivers of landscape change in the early to mid Holocene in the region, two topographically contrasting sites on the Isle of Skye and the Isle of Bute were investigated. A multiproxy approach including pollen, spore, microcharcoal, loss on ignition and particle size analyses was adopted to investigate changes in vegetation and climate. There are subtle indications that the 8200 cal BP climate event had an effect on the vegetation composition at both sites. Signals of anthropogenic woodland clearance are apparent early in the sequence at Peat Hill (Bute), indicated by a peak in Poaceae (grass) cereal-type (7–14%) at 8592–8793 cal BP, alongside a decrease in arboreal pollen, which could not be associated with a regional episode of climate change. Early to mid Holocene vegetation changes at Lyndale House (Skye) occur alongside regional changes in precipitation and sea level and therefore cannot be readily separated. Continuous declines in arboreal pollen from ca. 5000 cal BP at Lyndale House indicates the onset of widespread clearance on Skye via felling and sustained grazing pressures.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.