Teija Alenius - Academia.edu (original) (raw)

Papers by Teija Alenius

The Holocene, 2024

This research explores the vegetation compositional changes between the fifth and third millenniu... more This research explores the vegetation compositional changes between the fifth and third millennium BC on the Karelian Isthmus (north-west Russia). Special emphasis is placed on studying the timing and magnitude of the impact of hunter-fisher-gatherers on the vegetation. First, we reconstruct the local vegetation around Lake Bolshoye Zavetnoye by using the Landscape Reconstruction Algorithm modelling. The application of different scenarios to the relevant source area of pollen is used to assess the local vegetation around Lake Bolshoye Zavetnoye (BZL) at specific distances from 500 to 3000 m. The regional vegetation reconstruction is assessed by using the REVEALS model. Second, we present new pollen and charcoal data from adjacent Lake Ikmenlampi (LI). Third, we calculate indices of vegetation change for BZL, LI and the region. We further explore the potential causes for these differences between the spatial scales and compare all these outcomes with local and regional archaeological data. The results show that foragers actively manipulated their environment. A shift towards more heliophilous conditions is shown by ca 4800 BC. Between 4000 and 3000 BC, an increase in archaeological material suggests intensive resource procurement and landscape management activities, particularly near settlements. Around the BZL site a local decrease in birch is observed from 4100 BC, coinciding with an increase in the rate of vegetation changes. Additionally, a decline in tree species (spruce, hazel, Alder) from 3500 to 3300 BC suggests human activities. The high fire frequency recorded between 4090 and 3150 BC further supports the presence of local human disturbances by the deliberate use of fire to create favourable living conditions. The results from the LI site go in the same direction with fluctuating abundances of spruce and the presence of pollen from Cannabis, Hordeum, Urtica and Plantago lanceolata from ca 4000 to 3600 BC, indicating the use of spruce-dominated forests and an early, incipient cultivation.

Vegetation History and Archaeobotany, Mar 8, 2007

The introduction and development of cultivation in eastern Finland was studied by pollen and char... more The introduction and development of cultivation in eastern Finland was studied by pollen and charcoal analysis of a palaeomagnetically dated sediment profile from Lake Orijärvi, in the vicinity of permanent prehistoric fields. The earliest changes of possibly anthropogenic origin are visible in the pollen data from 1630 B.C. onwards and indications of human impact become more evident from 500 B.C. onwards. According to finds of cereal pollen and AMS-dating of charred cereal grains from the oldest field layer, the onset of cultivation can be dated to the Merovingian period around A.D. 600. To a significant extent the pollen data reflect only the cultivation of Secale during the first 600 years. The marked intensification of agricultural activities including cultivation in permanent fields only becomes evident in the pollen data from about A.D. 1050 to 1080 onwards and the most intensive land use phase dates to A.D. 1300-1965. Archaeological and palaeoecological material indicate that swidden cultivation and permanent field cultivation were in use simultaneously during the late Iron Age. The combination of these techniques together with animal husbandry and hunting formed a subsistence strategy in the climatic border-zone outside the centres of the agricultural core areas.

Palaeogeography, Palaeoclimatology, Palaeoecology, Apr 1, 2005

Physical properties of varves formed over the last ca. 10 000 years from Lake Nautaj7rvi, central... more Physical properties of varves formed over the last ca. 10 000 years from Lake Nautaj7rvi, central southern Finland provide a potential proxy record of winter precipitation and temperature via catchment runoff and erosion. The seasonal-scale varved data indicate that the winter severity and duration of summer growing season has changed considerably during the Holocene in southern central Finland. Periods of increased catchment erosion occurred at 7590-7530 BC,

The Holocene, Jun 1, 2008

A detailed understanding of decadal to millennial-scale climate changes requires seasonal-scale (... more A detailed understanding of decadal to millennial-scale climate changes requires seasonal-scale (summer-winter) reconstructions of past precipitation and temperature fluctuations. Comparing seasonally resolved varve records with pollen-based sum of growing degree-days (GDD) reconstructions from Lake Nautajärvi, we examined the intra-annual nature of climate variability in central southern Finland during the Holocene. The organic varve record and the GDD reconstruction show roughly comparable trends supporting the interpretation that both proxies predominantly reflect summer temperatures in the study area. The records suggest low but rising early-Holocene (9500 to 8500 cal. yr BP) summer temperatures. The Holocene Thermal Maximum (HTM) in the GDD record dates to about 7500 to 4500 cal. yr BP, but the organic varve record along with reconstructed changes in vegetation composition, notably a peak of Tilia pollen percentages, indicate that during the HTM there was a trend towards a more continental climate with maximum mid-summer temperatures reached at 6500 to 4500 cal. yr BP. Both records reflect the start of the post-HTM cooling at about 4500 cal. yr BP, simultaneously with an increase of the amount of catchment erosion and mineral matter influx into the lake, suggesting gradually colder and/or longer winters with high net accumulation of snow. The organic varve record and the GDD record start to diverge at 2000 cal. yr BP, possibly owing to the human influence on catchment processes. The reconstructed mid-Holocene summer temperature peak deviates from the regional climate model outputs, which suggest highest summer temperatures during the early Holocene.

Vegetation History and Archaeobotany, Mar 1, 2004

Agricultural history was investigated by means of pollen and charcoal analyses from the sediment ... more Agricultural history was investigated by means of pollen and charcoal analyses from the sediment of Lake Kirjavalampi in the Riekkalansaari Island, in the northern archipelago of Lake Ladoga, NW Russia (6144 0 N, 3046 0 E). Pollen and charcoal stratigraphies, and loss-on-ignition were analysed from a 0-294-cm profile cored from the deepest part of the small lake. The pollen profile was divided into six local pollen assemblage zones Kir 1-6 and dated by three radiocarbon samples. Lake Kirjavalampi was isolated from Lake Ladoga between 1460-1300 b.c., when the River Neva was formed as a new outlet for Lake Ladoga and the water level rapidly fell. The isolation is seen as a phase of rapid sedimentation in Kir 2 (237-173 cm). Spruce (Picea) starts to decline at 113 cm ca. a.d. 70, and the earliest cereal (Secale cereale) pollen was encountered at the 97-cm level, empirically dating the onset of cultivation to ca. a.d. 600. A marked intensification in agricultural activities occurs around a.d. 1200, and the indication of an open cultivated landscape is at its strongest during the time period 1700 to 1850.

The historical Ostrobothnian (Finland) burial tradition is poorly known, particularly when discus... more The historical Ostrobothnian (Finland) burial tradition is poorly known, particularly when discussed from the environmental archaeological viewpoint. This article examines Late Medieval burial meth ...

Environmental change and anthropogenic impact on lake sediments during the Holocene in the Finnis... more Environmental change and anthropogenic impact on lake sediments during the Holocene in the Finnish − Karelian inland area

PP21B-1330 During the last postglacial evolution of the shallow northern Siberian shelf systems r... more PP21B-1330 During the last postglacial evolution of the shallow northern Siberian shelf systems regional sea level in the Arctic came to its Holocene highstand some time between 5 to 6 ka. After that time a general stabilization of the sedimentary regime occurred. That is well noted in a drastic decrease in sedimentation rates observed in all sediment cores taken from middle to outer shelf water depths of the Laptev Sea. But, at water depths lower than 30 meters – i.e., in the inner shelf and nearer to the coasts – sedimentation continued at relatively higher rates, presumably due to input of terrigenous material from river runoff as well as coastal erosion. Compared with that latter process, the huge Lena Delta should comprise a region of sediment catchment where aggradation wins over erosion. However, little is known about the detailed history of this delta during the second half of the Holocene. In order to gain more insight into this issue we have investigated three islands with...

Environmental Archaeology

Moilanen, U., Juhola, T., Pätsi, S., Vanhanen, S. & Alenius, T. 2022. 'The Color ... more Moilanen, U., Juhola, T., Pätsi, S., Vanhanen, S. & Alenius, T. 2022. 'The Color of the Grave is Green' - Moss and Juniper in Early Medieval Graves at Toppolanmäki, Finland. Environmental Archaeology, doi:10.1080/14614103.2022.2083927 Two graves, initially discovered in the 1930s, were reopened and examined in 2017 and 2018 at the Early Medieval cemetery of Toppolanmäki, Finland. Soil samples taken from the graves were sampled for macrofossils, pollen and microfauna. Pollen and spore analysis provided possible evidence for the use of mosses and juniper branches in the graves. Also, mossindicating microfauna (Euglypha spp.) was detected. At Toppolanmäki, mosses were used in both coffins and earth burials. The clubmoss found in the latter could even indicate the presence of a woven carpet or mattress in the grave pit. The use of juniper, on the other hand, could indicate ritual continuation from the Iron Age as it is a common find in older cemeteries. It is also possible that the early medieval environment around the site was characterised by dry meadows and juniper bushes at the time of the burial, and even that one of the burials took place in early summer. The study highlights the research potential of graves that have been excavated decades ago and presents a new biological indicator of the use of moss in burials: the testate amoeba Euglypha.

Environmental Archaeology

Hiidenkivi : suomalainen kulttuurilehti, 2010

Palaeogeography, Palaeoclimatology, Palaeoecology, 2022

The Holocene, 2014

Precise timing of natural and cultural events provides a foundation for understanding how past na... more Precise timing of natural and cultural events provides a foundation for understanding how past natural phenomena have driven changes in population and culture. In this study, we used high-resolution Bayesian chronology to describe an event sequence of a massive and abrupt water level decline of a large lake and the contemporaneous cultural changes that occurred in eastern Fennoscandia during the mid-Holocene. The study provides the first transdisciplinary analysis of the causes and effects of the events by using a combination of archaeological, geological and ecological data. Nearly 6000 years ago, ancient Lake Saimaa, estimated to cover nearly 9000 km2at the time, was abruptly discharged through a new outlet. The event created thousands of square kilometres of new residual wetlands. The archaeological record shows a profound cultural replacement and a subsequent sharp human population maximum in the area during the decades after the decline in water level. During the population max...

The Holocene, 2024

This research explores the vegetation compositional changes between the fifth and third millenniu... more This research explores the vegetation compositional changes between the fifth and third millennium BC on the Karelian Isthmus (north-west Russia). Special emphasis is placed on studying the timing and magnitude of the impact of hunter-fisher-gatherers on the vegetation. First, we reconstruct the local vegetation around Lake Bolshoye Zavetnoye by using the Landscape Reconstruction Algorithm modelling. The application of different scenarios to the relevant source area of pollen is used to assess the local vegetation around Lake Bolshoye Zavetnoye (BZL) at specific distances from 500 to 3000 m. The regional vegetation reconstruction is assessed by using the REVEALS model. Second, we present new pollen and charcoal data from adjacent Lake Ikmenlampi (LI). Third, we calculate indices of vegetation change for BZL, LI and the region. We further explore the potential causes for these differences between the spatial scales and compare all these outcomes with local and regional archaeological data. The results show that foragers actively manipulated their environment. A shift towards more heliophilous conditions is shown by ca 4800 BC. Between 4000 and 3000 BC, an increase in archaeological material suggests intensive resource procurement and landscape management activities, particularly near settlements. Around the BZL site a local decrease in birch is observed from 4100 BC, coinciding with an increase in the rate of vegetation changes. Additionally, a decline in tree species (spruce, hazel, Alder) from 3500 to 3300 BC suggests human activities. The high fire frequency recorded between 4090 and 3150 BC further supports the presence of local human disturbances by the deliberate use of fire to create favourable living conditions. The results from the LI site go in the same direction with fluctuating abundances of spruce and the presence of pollen from Cannabis, Hordeum, Urtica and Plantago lanceolata from ca 4000 to 3600 BC, indicating the use of spruce-dominated forests and an early, incipient cultivation.

Vegetation History and Archaeobotany, Mar 8, 2007

The introduction and development of cultivation in eastern Finland was studied by pollen and char... more The introduction and development of cultivation in eastern Finland was studied by pollen and charcoal analysis of a palaeomagnetically dated sediment profile from Lake Orijärvi, in the vicinity of permanent prehistoric fields. The earliest changes of possibly anthropogenic origin are visible in the pollen data from 1630 B.C. onwards and indications of human impact become more evident from 500 B.C. onwards. According to finds of cereal pollen and AMS-dating of charred cereal grains from the oldest field layer, the onset of cultivation can be dated to the Merovingian period around A.D. 600. To a significant extent the pollen data reflect only the cultivation of Secale during the first 600 years. The marked intensification of agricultural activities including cultivation in permanent fields only becomes evident in the pollen data from about A.D. 1050 to 1080 onwards and the most intensive land use phase dates to A.D. 1300-1965. Archaeological and palaeoecological material indicate that swidden cultivation and permanent field cultivation were in use simultaneously during the late Iron Age. The combination of these techniques together with animal husbandry and hunting formed a subsistence strategy in the climatic border-zone outside the centres of the agricultural core areas.

Palaeogeography, Palaeoclimatology, Palaeoecology, Apr 1, 2005

Physical properties of varves formed over the last ca. 10 000 years from Lake Nautaj7rvi, central... more Physical properties of varves formed over the last ca. 10 000 years from Lake Nautaj7rvi, central southern Finland provide a potential proxy record of winter precipitation and temperature via catchment runoff and erosion. The seasonal-scale varved data indicate that the winter severity and duration of summer growing season has changed considerably during the Holocene in southern central Finland. Periods of increased catchment erosion occurred at 7590-7530 BC,

The Holocene, Jun 1, 2008

A detailed understanding of decadal to millennial-scale climate changes requires seasonal-scale (... more A detailed understanding of decadal to millennial-scale climate changes requires seasonal-scale (summer-winter) reconstructions of past precipitation and temperature fluctuations. Comparing seasonally resolved varve records with pollen-based sum of growing degree-days (GDD) reconstructions from Lake Nautajärvi, we examined the intra-annual nature of climate variability in central southern Finland during the Holocene. The organic varve record and the GDD reconstruction show roughly comparable trends supporting the interpretation that both proxies predominantly reflect summer temperatures in the study area. The records suggest low but rising early-Holocene (9500 to 8500 cal. yr BP) summer temperatures. The Holocene Thermal Maximum (HTM) in the GDD record dates to about 7500 to 4500 cal. yr BP, but the organic varve record along with reconstructed changes in vegetation composition, notably a peak of Tilia pollen percentages, indicate that during the HTM there was a trend towards a more continental climate with maximum mid-summer temperatures reached at 6500 to 4500 cal. yr BP. Both records reflect the start of the post-HTM cooling at about 4500 cal. yr BP, simultaneously with an increase of the amount of catchment erosion and mineral matter influx into the lake, suggesting gradually colder and/or longer winters with high net accumulation of snow. The organic varve record and the GDD record start to diverge at 2000 cal. yr BP, possibly owing to the human influence on catchment processes. The reconstructed mid-Holocene summer temperature peak deviates from the regional climate model outputs, which suggest highest summer temperatures during the early Holocene.

Vegetation History and Archaeobotany, Mar 1, 2004

Agricultural history was investigated by means of pollen and charcoal analyses from the sediment ... more Agricultural history was investigated by means of pollen and charcoal analyses from the sediment of Lake Kirjavalampi in the Riekkalansaari Island, in the northern archipelago of Lake Ladoga, NW Russia (6144 0 N, 3046 0 E). Pollen and charcoal stratigraphies, and loss-on-ignition were analysed from a 0-294-cm profile cored from the deepest part of the small lake. The pollen profile was divided into six local pollen assemblage zones Kir 1-6 and dated by three radiocarbon samples. Lake Kirjavalampi was isolated from Lake Ladoga between 1460-1300 b.c., when the River Neva was formed as a new outlet for Lake Ladoga and the water level rapidly fell. The isolation is seen as a phase of rapid sedimentation in Kir 2 (237-173 cm). Spruce (Picea) starts to decline at 113 cm ca. a.d. 70, and the earliest cereal (Secale cereale) pollen was encountered at the 97-cm level, empirically dating the onset of cultivation to ca. a.d. 600. A marked intensification in agricultural activities occurs around a.d. 1200, and the indication of an open cultivated landscape is at its strongest during the time period 1700 to 1850.

The historical Ostrobothnian (Finland) burial tradition is poorly known, particularly when discus... more The historical Ostrobothnian (Finland) burial tradition is poorly known, particularly when discussed from the environmental archaeological viewpoint. This article examines Late Medieval burial meth ...

Environmental change and anthropogenic impact on lake sediments during the Holocene in the Finnis... more Environmental change and anthropogenic impact on lake sediments during the Holocene in the Finnish − Karelian inland area

PP21B-1330 During the last postglacial evolution of the shallow northern Siberian shelf systems r... more PP21B-1330 During the last postglacial evolution of the shallow northern Siberian shelf systems regional sea level in the Arctic came to its Holocene highstand some time between 5 to 6 ka. After that time a general stabilization of the sedimentary regime occurred. That is well noted in a drastic decrease in sedimentation rates observed in all sediment cores taken from middle to outer shelf water depths of the Laptev Sea. But, at water depths lower than 30 meters – i.e., in the inner shelf and nearer to the coasts – sedimentation continued at relatively higher rates, presumably due to input of terrigenous material from river runoff as well as coastal erosion. Compared with that latter process, the huge Lena Delta should comprise a region of sediment catchment where aggradation wins over erosion. However, little is known about the detailed history of this delta during the second half of the Holocene. In order to gain more insight into this issue we have investigated three islands with...

Environmental Archaeology

Moilanen, U., Juhola, T., Pätsi, S., Vanhanen, S. & Alenius, T. 2022. 'The Color ... more Moilanen, U., Juhola, T., Pätsi, S., Vanhanen, S. & Alenius, T. 2022. 'The Color of the Grave is Green' - Moss and Juniper in Early Medieval Graves at Toppolanmäki, Finland. Environmental Archaeology, doi:10.1080/14614103.2022.2083927 Two graves, initially discovered in the 1930s, were reopened and examined in 2017 and 2018 at the Early Medieval cemetery of Toppolanmäki, Finland. Soil samples taken from the graves were sampled for macrofossils, pollen and microfauna. Pollen and spore analysis provided possible evidence for the use of mosses and juniper branches in the graves. Also, mossindicating microfauna (Euglypha spp.) was detected. At Toppolanmäki, mosses were used in both coffins and earth burials. The clubmoss found in the latter could even indicate the presence of a woven carpet or mattress in the grave pit. The use of juniper, on the other hand, could indicate ritual continuation from the Iron Age as it is a common find in older cemeteries. It is also possible that the early medieval environment around the site was characterised by dry meadows and juniper bushes at the time of the burial, and even that one of the burials took place in early summer. The study highlights the research potential of graves that have been excavated decades ago and presents a new biological indicator of the use of moss in burials: the testate amoeba Euglypha.

Environmental Archaeology

Hiidenkivi : suomalainen kulttuurilehti, 2010

Palaeogeography, Palaeoclimatology, Palaeoecology, 2022

The Holocene, 2014

Precise timing of natural and cultural events provides a foundation for understanding how past na... more Precise timing of natural and cultural events provides a foundation for understanding how past natural phenomena have driven changes in population and culture. In this study, we used high-resolution Bayesian chronology to describe an event sequence of a massive and abrupt water level decline of a large lake and the contemporaneous cultural changes that occurred in eastern Fennoscandia during the mid-Holocene. The study provides the first transdisciplinary analysis of the causes and effects of the events by using a combination of archaeological, geological and ecological data. Nearly 6000 years ago, ancient Lake Saimaa, estimated to cover nearly 9000 km2at the time, was abruptly discharged through a new outlet. The event created thousands of square kilometres of new residual wetlands. The archaeological record shows a profound cultural replacement and a subsequent sharp human population maximum in the area during the decades after the decline in water level. During the population max...

Radiocarbon and Archaeology, Ghent, Belgium, 2013