INVESTIGATING THE INFLUENCE OF LANDSCAPE DISTURBANCE AND CONNECTIVITY ON HIGH LATITUDE AND ARCTIC AQUATIC SYSTEMS: A PALEOLIMNOLOGICAL APPROACH

Abstract

Connectivity across the terrestrial-aquatic interface drives transport of sediments and nutrients to aquatic systems, a relationship that is significant to historically undisturbed and unproductive lakes. The purpose of this research was to investigate and review disturbance-driven connectivity changes to lakes located within western Scotland and the western Canadian Arctic. The review of existing literature for the paleoenvironmental history of western Scotland revealed the co-linear relationship of climatic and anthropogenic signals within paleo records and provided insights to how they have been dealt with. Specifically, existing records suggest long-term human occupation can result in increased terrestrial-aquatic connectivity that may alter the state of impacted aquatic systems, the literature suggests the integrity of paleoclimate results within areas of known disturbance may be upheld by careful site and proxy selection. The role of landscape disturbance was also investigated in the uplands region of the Mackenzie River Delta, N.W.T., through lacustrine sediment core analyses. The quantitative investigation of two lakes located within a transitional permafrost gradient suggest landscape disturbance confounds temperature reconstructions and increases productivity of nearby aquatic systems, which can alter trophic status and result in biological thresholds being crossed by species once confined to more southernly ranges. Thus, interpretations of biological indicators in areas that are prone to landscape disturbance, particularly under warming climate and high anthropogenic influence conditions, are necessary for detangling the competing signals of climate and disturbance, providing greater confidence to reconstruction results. This research suggests the importance of considerations of landscape disturbance within paleolimnological research and contributes new evidence to our understanding of lake status changes within the western Canadian Arctic.