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Changes in vegetation biomass have a great impact on many aspects of the Arctic ecosystem, and historical variations of biomass in Svalbard during the Holocene remain poorly understood. In this study, we collected a palaeo-notch sediment profile in Ny-Ålesund, Svalbard, performed organic biomarker and geochemical analysis on the sediments, reconstructed the photosynthetic biomass record during the interval of 9400–2200 BP, and examined the relationship between the photosynthetic biomass changes and Holocene temperature records in the Arctic region. The photosynthetic biomass production in Ny-Ålesund experienced four development periods. It rose steadily at the beginning of the Holocene and became stabilized at a high level during the Holocene thermal maximum. However, the photosynthetic biomass dropped sharply during the mid-Holocene transition. After that, it showed a small peak during the interval of 3000–2500 BP. The historical photosynthetic biomass record is in good agreement with the temperature records: the photosynthetic biomass production increases during warmer periods, and vice versa. Therefore, temperature is likely the driving factor controlling the photosynthetic biomass production. This study improves our understanding of the terrestrial ecosystem and its responses to climate change in the Arctic. [ABSTRACT FROM AUTHOR]

The distribution of antimony (Sb) in topsoil and moss (Dicranum angustum) in disturbed and undisturbed areas, as well as coal and gangue, in Ny-Ålesund, Arctic was examined. Results show that the weathering of coal bed could not contribute to the increase of Sb concentrations in topsoil and moss in the study area. The distribution of Sb is partially associated with traffic and historical mining activities. The occurrence of the maximum Sb concentration is due to the contribution of human activities. In addition, the decrease of Sb content in topsoil near the coastline may be caused by the washing of seawater. Compared with topsoils, moss could be a useful tool for monitoring Sb in both highly and lightly polluted areas. [Copyright &y& Elsevier]

Jiang, S., Liu, X., Sun, J., Yuan, L., Sun, L. & Wang, Y. 2011: A multi-proxy sediment record of late Holocene and recent climate change from a lake near Ny-Ålesund, Svalbard. Boreas, Vol. 40, pp. 468-480. 10.1111/j.1502-3885.2010.00198.x. ISSN 0300-9483 The Arctic constitutes a unique and important environment with a significant role in the dynamics and evolution of the earth system. Arctic lake sediments, which accumulate slowly over time, contain abundant information about the biological communities that lived within the water body, as well as in the surrounding catchment. In this study, we collected a sediment core from Ny-Ålesund, Svalbard, performed multi-proxy analyses on sediment pigments, mineral magnetic susceptibility, various sediment quality (i. e. organic matter content, CaCO content, carbon and nitrogen isotope), and diatom composition, and reconstructed the history of ecosystem responses to environmental variations, especially regarding aquatic productivity and lake catchment surface processes. Ny-Ålesund has undergone distinct ecological and climatic changes. During the Little Ice Age, the cold climate was unfavourable for the growth of lake algae, and therefore the lake primary productivity declined. After about AD 1890 and during the 20th century, the warming climate and reduced ice cover led to rapid lithological change and growth of lake algae, enhanced lake primary productivity, and increased input of nutrients derived from increased chemical weathering into the lake. The lake ecosystem on Ny-Ålesund has had rapid responses to climatic and environmental changes in the Arctic. [ABSTRACT FROM AUTHOR]

The Arctic region is very sensitive to climate change and important in the Earth’s climate system. However, proxy datasets for Arctic climate are unevenly distributed and especially scarce for Svalbard because glaciers during the Little Ice Age, the most extensive in the Holocene, destroyed large quantities of sediment records in Svalbard. Fortunately, palaeo-notch sediments could withstand glaciers and be well-preserved after deposition. In this study, we reconstructed a mid-to-late Holocene record of climate changes in a palaeo-notch sediment sequence from London Island. Multiple weathering indices were determined, they all showed consistent weathering conditions in the study area, and they were closely linked to climate changes. Total organic carbon (TOC) and total nitrogen (TN) were also determined, and their variation profiles were similar to those of weathering indices. The climate change record in our sediment sequence is consistent with ice rafting record from North Atlantic and glacier activity from Greenland, Iceland and Svalbard, and four cold periods are clearly present. Our study provides a relatively long-term climate change record for climate conditions from mid-to-late Holocene in Svalbard. [ABSTRACT FROM AUTHOR]