Factors affecting the water chemistry of non-glaciated high arctic catchments : a snapshot study of Lake Sarsvatnet, Svalbard

• Main Author: Gorseth, Lill Katrin
• Other Authors: Rohrlack, Thomas, Riise, Gunnhild
• Format: Master Thesis
• Language: English
• Published: Norwegian University of Life Sciences, Ås 2022
• Subjects: Sarsvatnet; Arctic; Svalbard; Norway; Arktis; Arktis*
• Online Access: https://hdl.handle.net/11250/3022155

The Arctic is warming up faster than the global average and the projected changes are believed to impact High Arctic freshwater systems. However, the consequences are poorly understood. To understand how these systems are responding to a changing climate, there is a need for baseline data. Here, a snapshot study of the water chemistry of a poorly investigated non-glaciated High Arctic catchment (Lake Sarsvatnet, Svalbard) is presented. The aim was to explore the main factors influencing these systems. With water samples from the lake and surrounding streams collected in August 2021, a picture of the freshwater chemistry was obtained including trace elements (Fe, Mn, Al, Ni, As, Co, Cu, Zn, Pb, Cd), major ions (Ca2+, HCO3-, SO42-, Mg2+, Cl-, Na+, K+), pH, conductivity, total organic carbon (TOC) and turbidity. Lake Sarsvatnet showed similar characteristics to other Svalbard lakes. However, elevated concentrations of Cu and Zn (total of 60.74 µg/l and 43.08 µg/l respectively) were found. Through a Principal Component Analysis (PCA) and sea salt correction, most of the trace element and major ion content in the streams was found to be explained by rock weathering and inputs from marine aerosols. However, Cd in stream samples could be linked to atmospheric deposition, which nowadays may originate from mineral dust from the erosion of newly ice-free environments on Svalbard. An enrichment of Pb, Mn, Fe, Cu, Zn and Cd in Lake Sarsvatnet compared to stream samples could plausibly be explained by the inwash of minerogenic material. This could have been initiated by precipitation events, which are expected to happen more frequently with a changing climate. Moreover, further research on seasonal and multi-seasonal variations in water chemistry is recommended to better understand climate-induced changes in the Arctic. Arktis varmes opp raskere enn andre steder i verden, og de tilhørende endringene er antatt å påvirke høyarktiske ferskvannssystemer. Derimot er konsekvensene usikre. For å bedre forstå hvordan disse ...