A One Hundred-Year-Study of Climate Change and the Upper Range of Tree Growth (Terminus arboreus) on MT. Getryggen in the Swedish Scandes – Updated Change in an Historical Perspective | Chapter 2 | Emerging Issues in Environment, Geography and Earth Science Vol. 9

 In the context of global climate change, positional treeline change since the early 20th century and up to 2023 was assessed along two elevational transects on Mt. Getryggen in the southern Swedish Scandes. Baseline data within permanent line transects, initially representing the year 1915, i.e. right at the onset of the present warming phase, were compared to later intermittent records up to 2023. These were complemented by repeat photography of individual trees. Concerned species were the regional treeline dominants; mountain birch (Betula pubescens ssp. czerepanovii), Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and Grey alder (Alnus incana). Treelines of these species responded with different degrees of upshifts, although with substantial inter-site variability, related to topoclimatic conditions. Betula displayed the largest advance, by 215 m over the entire past 100 years. This maximum magnitude of change complies with data from widely different parts of the Swedish Scandes. Such a common performance indicates that regionally recorded summer and winter warming by 1.4 and 1.9°C, respectively, is the ultimate cause. In a long-term historical perspective, recorded by local megafossil tree remnants, most congenial conditions for birch and pine growth at high elevations prevailed around 10 500-9400 cal. yr BP, when the local treeline of Betula and Pinus reached 1355 and 1250 m a.s.l., respectively. The former elevation coincides with the upper limit of Vaccinium myrtillus and the upper range of the low-alpine belt. With the exception of Pinus, recent treeline upshifts were mainly accomplished by phenotypic responses of millennial-old krummholz specimens (environmentally dwarfed modes), prevailing as relicts above the treeline by the early 20th century. Only occasionally, has treeline advance by Betula and Picea originated from seed regeneration during the past century. These circumstances may set the limit for further rapid and extensive advance of the last-mentioned species, where and when the pool of high-altitude old-established krummholz specimens becomes depleted. The prospect of further advance of seed disseminated Pinus, is judged to be higher, according to recent trends.

Author(s) Details:

Leif Kullman,
Department of Ecology and Environmental Science, Umeå University, SE 901 87 Umeå, Sweden.

Lisa Öberg,
Old Tjikko Photo Art & Science, Handöl 544, SE 837 71, Duved, Sweden.

Please see the link here: https://stm.bookpi.org/EIEGES-V9/article/view/13830

Largest Rises of Swedish Treelines, Consistent with Climate Change Since the Early-20th Century| Chapter 2 | Challenging Issues on Environment and Earth Science Vol. 6

 Repeat in situ measurements were taken at 14 places across the Swedish Scandes, spanning 800 kilometres from south to north, to estimate treeline advance during the last 100 years. Mountain birch (Betula pubescens ssp. czerepanovii), Norway spruce (Picea abies), Scots pine (Pinus sylvestris), and rowan were among the threatened species (Sorbus aucuparia). The highest height with trees at least 2 metres tall was considered as treeline. The focus is on sites with the most widespread treeline shifts, according to previous regional surveys, in order to reveal the entire influence and strength of climate change on the treeline area. Local limitations (topoclimate) were reduced as a result. Sorbus, Betula, and Picea The phenotypic height growth increment of old-established krummholz achieved treeline rise, whereas Pinus responded by establishing and growing new specimens. Regardless of species, the largest upshifts were in the order of 200 m. (max. 245 m). In terms of historical treeline movements, the new and higher treelines are similar to those that existed around 7000 years ago. Unlike earlier generalisations, there were no evident distinctions between the southern and northern hemispheres. Scandes. The measured rise appears to be a totally expected reaction, based on a common temperature lapse rate of 0.6°C per 100 m altitude and reported regional and centennial summer warming of 1.7°C. This type of performance suggests that, in circumstances of climate warming, treelines are in balance with climate on a centennial scale at optimal sites.

Author(s) Details

Leif Kullman
Department of Ecology and Environmental Science, Umeå University, SE 901 87 Umeå, Sweden.

View Book :- https://stm.bookpi.org/CIEES-V6/article/view/2828

Research on Mykert-Sanzheevka Field of Polycomponent Ores (Pb, Zn, Ag, Au, PGE): Geologic-Substance Characteristics and Formation Features of Ore-Forming System | Chapter 2 | Challenging Issues on Environment and Earth Science Vol. 2

 The latest findings from geologic-structural, petrographic, and mineralogic-geochemical studies of the Mykert-Sanzheevka ore field—the Uda-Vitim mineragenic region in West Transbaikalia's south-west end—are presented. The research findings of noble-metal-polymetallic mineralization in the Mykert-Sanzheevka ore area are discussed in this paper. Losange represents the main ore-controlling system, which is made up of rhombohedral and tetrahedral blocks-duplexes mosaic clusters divided by narrow tectonic sutures. It has been developed that these small-block sutures confine polycomponent ores clusters. Subvolcanic dykes of the shoshonitelatite volcanoplutonic association (233-188 million years), apodyke dynamometamorphites (breccias, cataclasite, mylonites), and mechanometasomatites are responsible for the formation. The formation of dynamometamorphites is divided into four phases, each of which is distinguished by different species compositions of ore minerals that occur as a result of mechanochemical reactions. The Sanzheevka mineral occurrence's Small Mykert field and Big Mykert form a single ore field. The formation of mineral microaggregates with films containing noble metal nanoparticles is proposed using a carbonyl model. The Mykert-Sanzheevka field's oreforming mechanism is studied.

Author (s) Details

Alexander Vasilyevich Tatarinov
Geological Institute, Siberian Branch, Russian Academy of Sciences, Ulan-Ude, Russia.

Lyubov Ilyinichna Yalovik
Geological Institute, Siberian Branch, Russian Academy of Sciences, Ulan-Ude, Russia.

Anatoly Georgievich Mironov
Geological Institute, Siberian Branch, Russian Academy of Sciences, Ulan-Ude, Russia.

Victor Fedorovich Posokhov
Geological Institute, Siberian Branch, Russian Academy of Sciences, Ulan-Ude, Russia.

View Book :- https://stm.bookpi.org/CIEES-V2/issue/view/60

A Review of Abisko Case Study: Recent and Past Trees an Climates at the Arctic/Alpine Margin in Swedish Lapland | Chapter 1 | Challenging Issues on Environment and Earth Science Vol. 2

 Abisko Scientific Research Station in northern Swedish Lapland has acted as a logistic centre for high-quality subalpine/subarctic geoecological research for nearly a century. Most of the research attention in recent years has been on complexities of the treeline ecotone, motivated by the possibility of alleged man-made global warming. Field observations, analyses, and interpretations resulting from research conducted in the Abisko area are discussed in light of recent observations and analyses in this context. The treeline rise of local mountain birch (Betula pubescens ssp. czerepanovii) by up to 230 metres over the last 100 years is quantitatively consistent with data obtained further south in the Scandes. This widespread inter-regional coincidence suggests that a single operative agent is to blame. Secular temperature warming of 2.5°C is the most likely candidate. This argument is backed up by age structure analysis in the birch treeline advance region, which shows that vegetative initiation of new trees peaked during the warm 1930s, when reindeer numbers were high, and peaked again during the cold 1960s and 1970s, when reindeer herds were smaller. These findings indicate that, in comparison to climate change, reindeer browsing strength has had a slight impact on birch treeline dynamics, contrary to previous hypotheses. Over the mainly warm past 100 years, the upper limit of closed mountain birch and pine stands has changed relatively insignificantly in elevation. Over the same time period or longer, low-growing krummholz (stunted growth forms) of common aspen (Populus tremula) have appeared frequently in the mountain birch area. Rapid height increment began in the warm 1930s, and has continued to this day, just as it did with birch. As a result, many people have grown to be the size of trees in recent decades. As a result, aspen (Populus tremula) has become a more prominent feature in the mountain birch forest, probably as a result of climate change. Prior arguments that aspen regeneration is achieved by seed regeneration rather than phenotypic modification of old-growth creeping individuals are refuted by the current research. In the Abisko field, new species such as Picea abies and Larix sp. have been discovered. Megafossil data indicate that Scots pine treelines are similar to those found in other parts of the Scandes (Pinus sylvestris), Summer temperatures may have surpassed those of the last few decades by around 3.0°C, based on the elevational disparity between early Holocene and present treeline positions (adjusted for 100 m land uplift). Recent reports that aspen is spreading upslope and westward in the birch forest belt through seed establishment of new individuals are questioned by this report. As a result of recent warming, they have grown to the size of trees and have become a more noticeable feature of the landscape.

Author (s) Details

Leif Kullman
Department of Ecology and Environmental Science, Umeå University, SE 901 87 Umeå, Sweden.

View Book :- https://stm.bookpi.org/CIEES-V2/issue/view/60