Woodland regeneration in a coastal heathland area in central Norway

The open coastal heathlands in Norway have changed character in recent decades, mainly because traditional practices such as burning, cutting and grazing have been abandoned or reduced. In a project aimed at increasing our knowledge of woodland regeneration in oceanic boreal heathlands, an area on the island of Kalv?ya in the archipelago of Vikna on the extreme outer coast of central Norway has been studied. Kalv?ya has calcareous bedrock; rich heath, rich fens and low-herb woodland cover 20% of the island. Large parts are paludified, and wet heath and mire vegetation cover 60%. The island has not been inhabited, but it was used for summer farming in the latter part of the 19th century and later for stock grazing. The woodland and scrub were mapped using aerial photographs from 1961 and 1981, and by fieldwork in 2001. Vegetation changes were analyzed using GIS techniques. Woodland and scrub increased from 3.0% in 1961, to 4.3% in 1981, to 11.6% in 2001. Betula pubescens is the commonest woody species. The oldest trees are 150 to 175 years old, growing in the most heavily wooded area, far away from the summer farm. In addition to human impact (summer farm, grazing pressure), the geology, terrain (degree of exposure), and climatic factors are important for woodland colonisation and distribution.     

BOOK REVIEW

Eolian landforms as sandy dunes and dune heaps were mapped by the author in 1979–1980 in a zone where vegetation had been destroyed by a forest fire on 30 June 1976, in an area to the east of Elverum, south-east Norway. The mapped eolian landforms are discussed together with information from 40 samples of the eolian sediment. Winds, mostly from the north and north-west, were responsible for the development of these eolian landforms, utilizing the fluvioglacial sediments accumulated as a sandur during the retreat of the inland ice approximately 10,000 years ago. The winds were active during a short period of time, only a century or so before the area became vegetated.     

Energy flux partitioning and evapotranspiration in a sub‐alpine spruce forest ecosystem

In this study, we examined the year 2011 characteristics of energy flux partitioning and evapotranspiration of a sub‐alpine spruce forest underlain by permafrost on the Qinghai–Tibet Plateau (QPT). Energy balance closure on a half‐hourly basis was H + λE = 0.81 × (R_n ? G ? S) + 3.48 (W m^?2) (r² = 0.83, n = 14938), where H, λE, R_n, G and S are the sensible heat, latent heat, net radiation, soil heat and air‐column heat storage fluxes, respectively. Maximum H was higher than maximum λE, and H dominated the energy budget at midday during the whole year, even in summer time. However, the rainfall events significantly affected energy flux partitioning and evapotranspiration. The mean value of evaporative fraction (Λ = λE/(λE + H)) during the growth period on zero precipitation days and non‐zero precipitation days was 0.40 and 0.61, respectively. The mean daily evapotranspiration of this sub‐alpine forest during summer time was 2.56 mm day^?1. The annual evapotranspiration and sublimation was 417 ± 8 mm year^?1, which was very similar to the annual precipitation of 428 mm. Sublimation accounted for 7.1% (30 ± 2 mm year^?1) of annual evapotranspiration and sublimation, indicating that the sublimation is not negligible in the annual water balance in sub‐alpine forests on the QPT. The low values of the Priestley–Taylor coefficient (α) and the very low value of the decoupling coefficient (Ω) during most of the growing season suggested low soil water content and conservative water loss in this sub‐alpine forest. Copyright © 2013 John Wiley & Sons, Ltd.     

Local traditions as a means for commercial production of historical beers: The case of Vossaøl,Norway

The aim of the article is to analyse challenges facing the commercial production of historical beers, which are ‘extinct’ beers. The concept of ‘fictive terroir’ is introduced to emphasize these challenges. The author addresses the following questions: What kind of knowledge is needed to produce historical beers? How can this knowledge be acquired? How can it be used commercially in craft breweries? The studied case is Vossaøl, a craft beer imitation of a beer produced in the early 19th century. The data were obtained from written sources and interviews with local home brewers and brewers at Voss Brewery in Norway. The study revealed the need to reconstruct the terroir in the early 19th century. Additionally, Voss Brewery had to acquire knowledge about how to process and combine the ingredients, which included the traditional yeast (kveik). Involving traditional home brewers was crucial to determine how ingredients could be combined to produce Vossaøl. The author concludes that a synthetic knowledge base was a useful point of departure in this respect. Participation in the traditional culture of brewing proved an important means when working with this knowledge base. The results are interesting in the broader context of the reconstruction of beverages and food.     

DNA tracers with information capacity and high detection sensitivity tested in groundwater studies

 In order to investigate the usefulness of unique synthetic DNA tracers in groundwater, a field experiment was conducted in Norway. DNA tracers and a sodium-chloride tracer were injected into an aquifer. The transport of DNA molecules was interpreted by comparing with the plume of chloride ions under forced-gradient steady-state flow conditions. Spatial concentration moments described the migration of conservative tracers. Mobility and migration of DNA in groundwater demonstrate that DNA tracers can be detected by using the polymerase chain reaction (PCR) and DNA sequence analysis. The results indicate that DNA tracers can be valuable tools as tracers in groundwater investigations. Received, June 1997 / Revised, July 1998, December 1998 / Accepted, January 1999     

Stable carbon isotope variations in northwest Europe during the last glacial–interglacial transition

Stable carbon isotope data that span part of the last glacial–interglacial transition (ca. 14-9 ka ¹⁴C BP; ca. 15–11 ka cal. BP), and which derive from organ-specific plant macrofossils recovered from two lake sediment profiles in the UK and one in Norway, are compared. The recorded temporal variations show similar trends, which, over a millennial time-scale appear to parallel the main drift in δ¹⁸O as determined for the GRIP ice-core. It is postulated that some smaller scale variations in the δ¹³C profiles may reflect the shorter term oscillations in δ¹⁸O values evident in the GRIP record, although this is less certain. Overall, however, the results suggest that stable carbon isotope measurements based on organ-specific terrestrial plant macrofossils may provide (i) a means for establishing correlations between terrestrial successions and (ii) additional paleoenvironmental information, as the apparent ‘shadowing’ of the GRIP record indicates a common forcing mechanism for both Greenland δ¹⁸O and northwest European δ¹³C variations. From the evidence available we suggest that the recorded δ¹³C variations reflect fluctuations in air temperature and/or changes in water vapour pressure in the atmosphere. © 1997 John Wiley & Sons, Ltd.     

Schmidt‐hammer exposure‐age dating (SHD) of snow‐avalanche impact ramparts in southern Norway: approaches,results and implications for landform age,dynamics and development

Schmidt‐hammer exposure‐age dating (SHD) was applied to the problem of dating the diachronous surfaces of five distal river‐bank boulder ramparts deposited by snow avalanches plunging into the Jostedøla and Sprongdøla rivers in the Jostedalsbreen region of southern Norway. Approaches to local high‐precision linear age calibration, which controlled in different ways for boulder roundness, were developed. The mean age (SHD_mean) and the maximum age (SHD_max) of surface boulders were estimated for whole ramparts, crests and distal fringes. Interpretation was further assisted by reference to R‐value distributions. SHD_mean ages (with 95% confidence intervals) ranged from 520 ± 270 years to 5375 ± 965 years, whereas SHD_max ages (expected to be exceeded by <5% of surface boulders) ranged from 675 to 9065 years. SHD ages from the Jostedøla ramparts tended to be older than those associated with the Sprongdøla, rampart crests were younger than the respective distal fringes, and use of relatively rounded boulders yielded more consistent SHD ages than angular boulders. The SHD_mean ages indicate differences in recent levels of snow‐avalanche activity between ramparts and provide insights into rampart dynamics as boulders are deposited on rampart crests and, in smaller numbers, on the distal fringes. SHD_max ages provide minimum age estimates of rampart age (i.e. the time elapsed since the ramparts began to form) and suggest that at least some of the ramparts have been developing since the early Holocene. Copyright © 2015 John Wiley & Sons, Ltd.     

Identifying Rocky Seabed Using GIS-Modeled Predictor Variables

Mapping the seabed along the Norwegian coast is costly and time consuming. Hence, finding a modeling method to separate rocky seabed from other substrate types will provide digital maps that may be used to develop cost-effective sampling designs to predict species and habitat distribution. Our approach was to use geophysical data that were quantitative and objectively defined, generalized additive models (GAMs), and Akaike information criterion (AIC) to develop statistical models and select among them. We found that slope, terrain curvature, wave exposure, and depth predicted rocky seabed occurrence with a high degree of certainty.     

ENDOLITHIC LICHENS,RAPID BIOLOGICAL WEATHERING AND SCHMIDT HAMMER R‐VALUES ON RECENTLY EXPOSED ROCK SURFACES: STORBREEN GLACIER FORELAND,JOTUNHEIMEN, NORWAY

The endolithic lichen Lecidea auriculata is known to enhance rock surface weathering on the Little Ice Age moraines of the glacier Storbreen in Jotunheimen, central southern Norway. This study demonstrates the reduction in Schmidt hammer Rvalues that followed the rapid colonization by this lichen of pyroxene‐granulite boulders on terrain deglaciated over the last 88 years. In the absence of this lichen, the characteristic mean R‐value of boulder surfaces is 61.0 ± 0.3; where this lichen is present, R‐values are lower by at least 20 units on surfaces exposed for 30–40 years. A similar reduction in rock hardness on rock surfaces without a lichen cover requires about 10 ka. The rapid initial weakening of the rock surfaces is indicative of rates of biological weathering by endolithic lichens that may be two orders of magnitude (200–300 times) faster than rates of physico‐chemical weathering alone. If not avoided, the effects of this type of lichen are likely to negate the effectiveness of the Schmidt hammer and other methods for exposure‐age dating, including cosmogenic‐nuclide dating, in severe alpine and polar periglacial environments. The results also suggest a new method for dating rock surfaces exposed for <50 years.