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Kullman, Leif
Alternative names
Publications (10 of 27) Show all publications
Kullman, L. (2020). Främmande trädarter sprids till svenska fjällbjörkskogar. Fauna & flora: en spegling av svensk natur, 115(1), 16-21
Open this publication in new window or tab >>Främmande trädarter sprids till svenska fjällbjörkskogar
2020 (Swedish)In: Fauna & flora: en spegling av svensk natur, E-ISSN 0014-8903, Vol. 115, no 1, p. 16-21Article in journal (Other (popular science, discussion, etc.)) Published
Place, publisher, year, edition, pages
Stenungsund: Naturcentrum AB, 2020
National Category
Biological Sciences
Identifiers
urn:nbn:se:umu:diva-177615 (URN)
Available from: 2020-12-15 Created: 2020-12-15 Last updated: 2020-12-17Bibliographically approved
Kullman, L. (2020). One hundred years later and in a warmer climate: A case of ecotonal treeline change in the Swedish Scandes. Ecology & Conservation Science: Open Access, 1(3), Article ID 555564.
Open this publication in new window or tab >>One hundred years later and in a warmer climate: A case of ecotonal treeline change in the Swedish Scandes
2020 (English)In: Ecology & Conservation Science: Open Access, ISSN 2689-4637, Vol. 1, no 3, article id 555564Article, review/survey (Refereed) Published
Abstract [en]

This paper accounts for a case of substantial transformation of the treeline ecotone (Picea abies (L.) Karst.) in the Swedish Scandes. Duringthe past 100 years, coinciding with summer warming by 1.6 °C, the ecotonal landscape changed from predominance of stunted krummholzindividuals to a mosaic of tree groves and intervening alpine tundra.

Place, publisher, year, edition, pages
Irvine: Juniper Publishers, 2020
Keywords
Treeline ecotone, Picea abies, Climate change, Swedish Scandes
National Category
Ecology Climate Research
Identifiers
urn:nbn:se:umu:diva-177614 (URN)10.19080/ECOA.2020.01.555564 (DOI)
Available from: 2020-12-15 Created: 2020-12-15 Last updated: 2021-04-29Bibliographically approved
Kullman, L. & Öberg, L. (2020). Shrinking glaciers and ice patches disclose megafossil trees and provide a vision of the Late-glacial and Early post-glacial subalpine/alpine landscape in the Swedish Scandes: review and perspective. Journal of Natural Sciences, 8(2), 1-15
Open this publication in new window or tab >>Shrinking glaciers and ice patches disclose megafossil trees and provide a vision of the Late-glacial and Early post-glacial subalpine/alpine landscape in the Swedish Scandes: review and perspective
2020 (English)In: Journal of Natural Sciences, ISSN 2334-2943, Vol. 8, no 2, p. 1-15Article in journal (Refereed) Published
Abstract [en]

Extensive glacier recession has prevailed for almost 100 years in the Scandes and other parts of the world. At the lower fringe and forefields of shrinking alpine glaciers and ice patches, a plethora of ancient tree remnants is recovered. This is presumably the first time of exposure since burialby ice thousands of years ago. These remains represent prior stands of virtually all boreal tree species, currently growing in northern Scandinavia. As a consequence, a previously unexpected and patchily treed high-mountain landscape emerges, in some cases 600-700 m higher than present-day treelines. This difference in treeline positions between then and now (corrected for land uplift) indicates that summer temperatures have declined by about 3 °C since the early Holocenetreeline maximum. Radiocarbon-dating reveals that the age of the tree remnants ranges between c. 16 800 and 2000 cal. yr BP. Initially,the high-mountainpeaks stood out asnunataks in a surrounding for long glaciated landscape at lower elevations. As the ice sheet gradually shrinked, glacier cirques and hollows became filled with tree groves, in a matrix of alpine tundra. In addition to Betulapubescens ssp. czerepanovii, Piceaabies and Pinussylvestris, these high-elevation enclaves contained tree species, previously unknown to such high positions and so early. These are Piceaabies and a species currently considered as exotic to Scandinavia, namely Larixsibirica. In response to gradual climate cooling since the middle Holocene, the tree stands declined and dead trees were eventually entombed by glacier ice, which is currently disintegrating.

Place, publisher, year, edition, pages
Madison: American Research Institute for Policy Development, 2020
National Category
Ecology Physical Geography
Identifiers
urn:nbn:se:umu:diva-177613 (URN)10.15640/jns.v8n2a1 (DOI)
Available from: 2020-12-15 Created: 2020-12-15 Last updated: 2021-05-03Bibliographically approved
Kullman, L. & Öberg, L. (2020). The recent history of subalpine krummholz pines (Pimus sylvestris) in the Swedish Scandes. International Journal of Research in Geography, 6(1), 16-28
Open this publication in new window or tab >>The recent history of subalpine krummholz pines (Pimus sylvestris) in the Swedish Scandes
2020 (English)In: International Journal of Research in Geography, ISSN 2454-8685, Vol. 6, no 1, p. 16-28Article in journal (Refereed) Published
Abstract [en]

This paper accounts for photographic surveys of stunted old-growth krummholz pines (Pinussylvestris) in the context of climate change and variability since the late 1970s and early 1980s. The study was conducted within the alpine-tundra ecotone of the southern Swedish Scandes. The life-histories of pineswith this shrubby and stunted growth mode are little studied. They may play some role as dispersal nuclei, contributing to elevational treeline rise in cases of future climate warming. In contrast to earlier assumptions, it now appears that pines, growing in open spaces of the subalpine birch forest belt, may regenerate vegetatively by layering, enabling surprisingly old ages. Having survived the harsh centuries of the Little Age, they have recently attained tree stature and started to produce offspring in their near vicinity. Thereby they contribute to ongoing pine treeline rise and transformation of the forest-alpine tundra ecotone. 

Place, publisher, year, edition, pages
ARC Publications, 2020
Keywords
Krummholz, Pinus sylvestris, treeline ecotone, climate change, regeneration. layering
National Category
Ecology
Identifiers
urn:nbn:se:umu:diva-177616 (URN)10.20431/2454-8685.0601003 (DOI)
Available from: 2020-12-15 Created: 2020-12-15 Last updated: 2020-12-16Bibliographically approved
Kullman, L. (2015). Higher-than-present medieval pine (Pinus sylvestris) treeline along the Swedish scandes. Landscape Online, 42(1), 1-14
Open this publication in new window or tab >>Higher-than-present medieval pine (Pinus sylvestris) treeline along the Swedish scandes
2015 (English)In: Landscape Online, E-ISSN 1865-1542, Vol. 42, no 1, p. 1-14Article in journal (Refereed) Published
Abstract [en]

The upper treeline of Scots pine (Pinus sylvestris L.) is renowned as a sensitive indicator of climate change and variability. By use of megafossil tree remains, preserved exposed on the ground surface, treeline shift over the past millennium was investigated at multiple sites along the Scandes in northern Sweden. Difference in thermal level between the present and the Medieval period, about AD 1000-1200, is a central, although controversial, aspect concerning the detection and attribution of anthropogenic climate warming. Radiocarbon-dated megafossil pines revealed that the treeline was consistently positioned as much as 115 m higher during the Medieval period than today (AD 2000-2010), after a century of warming and substantial treeline upshift. Drawing on the last-mentioned figure, and a lapse rate of 0.6<sup>o</sup>C/100 m, it may be inferred that Medieval summer temperatures were about 0.7 <sup>o</sup>C warmer than much of the past 100 years. Extensive pine mortality and treeline descent after the Medieval warming peak reflect substantially depressed temperatures during the Little Ice Age. Warmer-than-present conditions during the Medieval period concur with temperature reconstructions from different parts of northern Fennoscandia, northwestern Russia and Greenland. Modern warming has not been sufficient to restore Medieval treelines. Against this background, there is little reason to view further modest warming as unnatural.

Place, publisher, year, edition, pages
International Association for Landscape Ecology, 2015
Keywords
Climate change, Little ice age, Medieval warm period, Megafossils, Pinus sylvestris, Swedish scandes, Treeline
National Category
Climate Research Ecology
Identifiers
urn:nbn:se:umu:diva-212352 (URN)10.3097/LO.201542 (DOI)2-s2.0-84940040383 (Scopus ID)
Available from: 2023-07-24 Created: 2023-07-24 Last updated: 2023-10-03Bibliographically approved
Kullman, L. & Oberg, L. (2015). New Aspects of High-Mountain Palaeobiogeography: A Synthesis of Data from Forefields of Receding Glaciers and Ice Patches in the Tarna and Kebnekaise Mountains, Swedish Lapland. Arctic, 68(2), 141-152
Open this publication in new window or tab >>New Aspects of High-Mountain Palaeobiogeography: A Synthesis of Data from Forefields of Receding Glaciers and Ice Patches in the Tarna and Kebnekaise Mountains, Swedish Lapland
2015 (English)In: Arctic, ISSN 0004-0843, E-ISSN 1923-1245, Vol. 68, no 2, p. 141-152Article in journal (Refereed) Published
Abstract [en]

Recent recession of high-mountain glacier ice and perennial snow and ice patches has exposed megafossil and macrofossil tree remnants and peat, offering a new source of Holocene high alpine vegetation history in the Scandes. Radiocarbon dates of 90 tree megafossils from Swedish Lapland, 29 of which had not previously been published, range from 11 980 to 1950 cal yr BP. During the interval 9500-8500 cal yr BP, mountain birch (Betula pubescens ssp. czerepanovii) and Scots pine (Pinus sylvestris) grew 600-700 m higher upslope than they do today, which is a new and remarkable discovery. Subsequently, tree density gradually declined at higher elevations, and as the tree line moved downslope, the ratio of Betula to Pinus increased. Tree growth ceased around 4500 cal yr BP, presumably in response to the return of perennial ice and snow. A short episode of resumed tree growth of Betula indicates conditions warmer than present around 2000 years ago. Between c. 8500 and 7300 cal yr BP, Picea abies, Larix sibirica, Populus tremula, Sorbus aucuparia and Alnus incana were subordinate species on a forest floor dominated by plant species characteristic of prealpine or subalpine woodlands. Growth of trees as much as 700 m higher upslope than today around 9500 cal yr BP implies that summer temperatures at that time may have been 3.0 degrees C warmer than today's temperatures (corrected for land uplift). This inferred temperature difference between the early Holocene and the present concurs with changes in the Earth's orbital parameters.

Keywords
glaciers, tree growth, megafossils, macrofossils, Holocene, radiocarbon dating, climate change, edish Scandes
National Category
Ecology
Identifiers
urn:nbn:se:umu:diva-107181 (URN)10.14430/ARCTIC4480 (DOI)000357907900001 ()2-s2.0-84936756173 (Scopus ID)
Available from: 2015-09-01 Created: 2015-08-19 Last updated: 2023-03-24Bibliographically approved
Kullman, L. (2015). När eken växte vild i fjällen - En varmare och rikare tid text: [When the oak was a mountain tree]. Svensk Botanisk Tidskrift, 109(5), 260-266
Open this publication in new window or tab >>När eken växte vild i fjällen - En varmare och rikare tid text: [When the oak was a mountain tree]
2015 (Swedish)In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 109, no 5, p. 260-266Article in journal (Refereed) Published
Abstract [sv]

Eken växte vild i våra södra fjälltrakter för 8000 år sedan. Det är slutsatsen man måste dra efter Leif Kullmans fynd av en barkbit påTäljstensvalen nära Handöl i sydvästra Jämtland.

Place, publisher, year, edition, pages
Svenska Botaniska Föreningen, 2015
National Category
Biological Sciences
Identifiers
urn:nbn:se:umu:diva-199955 (URN)2-s2.0-84946027213 (Scopus ID)
Available from: 2022-10-10 Created: 2022-10-10 Last updated: 2022-10-10Bibliographically approved
Kullman, L. (2014). Recent cooling and dynamic responses of alpine summit floras in the southern Swedish Scandes. Nordic Journal of Botany, 32(3), 369-376
Open this publication in new window or tab >>Recent cooling and dynamic responses of alpine summit floras in the southern Swedish Scandes
2014 (English)In: Nordic Journal of Botany, ISSN 0107-055X, E-ISSN 1756-1051, Vol. 32, no 3, p. 369-376Article in journal (Refereed) Published
Abstract [en]

Changes in plant species richness on alpine summits in the southern Swedish Scandes were analyzed between 2004/2006 and 2012. This period experienced consistent summer and winter cooling and finalized with a cold and snow rich summer 2012. Re-surveys of these summits had previously documented substantial increases in species numbers in concordance with climate warming since the mid-20th century. Over the present study period, species richness decreased by 25-46%. The majority of lost species were those that had advanced upslope during the previous warm episode. Cooling since the mid 2000s and particularly the unusually short and snow-rich growth period in 2012 caused a floristic retrogression. Taken together with extensive upshifts of many species during previous relative warm decades, recent downshifts highlight the large capability of certain alpine species to track their ecological niches as climate changes. The pivotal importance of unusually late-lying snow in 2012, suggests that snow cover phenology exerts a more direct effect on the composition of the alpine flora than ambient temperatures. Dynamic modeling of future ecological landscape evolution needs to consider episodes of the kind reported here.

National Category
Climate Research Botany
Identifiers
urn:nbn:se:umu:diva-91211 (URN)10.1111/j.1756-1051.2013.00229.x (DOI)000337743100013 ()2-s2.0-84902553533 (Scopus ID)
Available from: 2014-07-21 Created: 2014-07-21 Last updated: 2023-03-24Bibliographically approved
Kullman, L. (2014). Treeline (Pinus sylvestris) landscape evolution in the Swedish Scandes - a 40-year demographic effort viewed in a broader temporal context. Norsk Geografisk Tidsskrift, 68(3), 155-167
Open this publication in new window or tab >>Treeline (Pinus sylvestris) landscape evolution in the Swedish Scandes - a 40-year demographic effort viewed in a broader temporal context
2014 (English)In: Norsk Geografisk Tidsskrift, ISSN 0029-1951, E-ISSN 1502-5292, Vol. 68, no 3, p. 155-167Article in journal (Refereed) Published
Abstract [en]

The article reports the outcome of long-term demographic monitoring of elevational treeline ecotonal stands of Scots pine (Pinus sylvestris L.) in the southern Swedish Scandes. Annual censuses were undertaken of recruitment, mortality, growth, seed viability, and causes of mortality during the period 1973-2012 in a set of 18 permanent plots. A net gain in total population size occurred over the study period as the result of periodic fluctuations in recruitment and mortality, broadly congruent with annual variations in summer and winter temperatures. Summer temperatures affected seed viability, establishment, and height growth. Winter temperatures exerted an impact foremost by changing the incidence of winter desiccation injury. As a result of infilling, pine has become a more prominent and vital component of the landscape around the forest limit, which has advanced insignificantly into the bordering mountain birch forest. The results highlight a rigid climate-forest disequilibrium and falsify models suggesting extensive and swift expansion of the treeline ecotone and closed forest at the expense of alpine tundra in response to anticipated future warming during the present century. The balance of evidence suggests that patchy forest expansion is likely to occur at a very slow (plurisecular) pace, given that climate warming prevails.

Place, publisher, year, edition, pages
Taylor & Francis Group, 2014
Keywords
mortality, recruitment, climate variability, treeline ecotone demography, landscape change
National Category
Ecology Other Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:umu:diva-88940 (URN)10.1080/00291951.2014.904402 (DOI)000334158600002 ()2-s2.0-84898648500 (Scopus ID)
Available from: 2014-05-21 Created: 2014-05-19 Last updated: 2023-03-24Bibliographically approved
Kullman, L. (2013). Ecological tree line history and palaeoclimate: review of megafossil evidence from the Swedish Scandes. Boreas, 42(3), 555-567
Open this publication in new window or tab >>Ecological tree line history and palaeoclimate: review of megafossil evidence from the Swedish Scandes
2013 (English)In: Boreas, ISSN 0300-9483, E-ISSN 1502-3885, Vol. 42, no 3, p. 555-567Article, review/survey (Refereed) Published
Abstract [en]

The postglacial tree line and climate history in the Swedish Scandes have been inferred from megafossil tree remains. Investigated species are mountain birch (Betula pubescens ssp. czerepanovii), Scots pine (Pinus sylvestris) and grey alder (Alnus incana). Betula and Pinus first appeared on early deglaciated nunataks during the Lateglacial. Their tree lines peaked between 9600 and 9000 cal. a BP, almost 600m higher than present-day elevations. This implies (adjusted for land uplift) that early Holocene summer temperatures may have been 2.3 degrees C above modern ones. Elevational tree line retreat characterized the Holocene tree line evolution. For short periods, excursions from this trend have occurred. Between c. 12000 and 10000 cal. a BP, a pine-dominated subalpine belt prevailed. A first major episode of descent occurred c. 8200 cal. a BP, possibly forced by cooling and an associated shift to a deeper and more persistent snow pack. Thereafter, the subalpine birch forest belt gradually evolved at the expense of the prior pine-dominated tree line ecotone. A second episode of pine descent took place c. 4800 cal. a BP. Historical tree line positions are viewed in relation to early 21st century equivalents, and indicate that tree line elevations attained during the past century and in association with modern climate warming are highly unusual, but not unique, phenomena from the perspective of the past 4800 years. Prior to that, the pine tree line (and summer temperatures) was consistently higher than present, as it was also during the Roman and Medieval periods, c. 1900 and 1000 cal. a BP, respectively.

National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:umu:diva-79042 (URN)10.1111/bor.12003 (DOI)000320782800006 ()2-s2.0-84879550512 (Scopus ID)
Available from: 2014-03-14 Created: 2013-08-06 Last updated: 2023-03-23Bibliographically approved
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