Witold Szczuciński | Adam Mickiewicz University in Poznań (original) (raw)

Papers by Witold Szczuciński

Acta Palaeobotanica, 2021

Lobelia dortmanna L. (Lobeliaceae family) is an indicator species that is predominantly found in ... more Lobelia dortmanna L. (Lobeliaceae family) is an indicator species that is predominantly found in oligotrophic and acidic lakes. They are mainly distributed in northwestern Europe. Their occurrence in Poland is highly threatened by the increasing grade of human activity and environmental eutrophication; however, new sites of Lobelia were discovered in the last few decades, for example, in Lake Krzywce Wielkie situated in Bory Tucholskie National Park (BTNP), Poland. The existence of Lobelia in this lake was unexpected because Cladium mariscus was also found in the lake. Cladium has different ecological demands and is regarded as a species typical of calcareous habitats where calcium is found in abundance in the substrate. To explain the coexistence of both species in Krzywce Wielkie, pollen analysis of organic sediments was performed for four short cores collected from the littoral zone of the lake and for one long deep-water core. Additionally, macrofossil analysis was done for all ...

Scientific Reports, 2020

Under conditions of global warming, organisms are expected to track their thermal preferences, in... more Under conditions of global warming, organisms are expected to track their thermal preferences, invading new habitats at higher latitudes and altitudes and altering the structure of local communities. To fend off potential invaders, indigenous communities/populations will have to rapidly adapt to the increase in temperature. In this study, we tested if decades of artificial water heating changed the structure of communities and populations of the Daphnia longispina species complex. We compared the species composition of contemporary Daphnia communities inhabiting five lakes heated by power plants and four non-heated control lakes. The heated lakes are ca. 3–4 °C warmer, as all lakes are expected to be by 2100 according to climate change forecasts. We also genotyped subfossil resting eggs to describe past shifts in Daphnia community structure that were induced by lake heating. Both approaches revealed a rapid replacement of indigenous D. longispina and D. cucullata by invader D. galeata immediately after the onset of heating, followed by a gradual recovery of the D. cucullata
population. Our findings clearly indicate that, in response to global warming, community restructuring may occur faster than evolutionary adaptation. The eventual recolonisation by D. cucullata indicates that adaptation to novel conditions can be time-lagged, and suggests that the long-term consequences of ecosystem disturbance may differ from short-term observations.

Przegląd Geologiczny, 2020

About 5,000 years ago near Morasko (the district of the present-day city of Poznañ, western Polan... more About 5,000 years ago near Morasko (the district of the present-day city of Poznañ, western Poland) the largest known iron meteorite shower in Central Europe took place. The evidence of that impact, documented so far, comprises numerous iron meteorite fragments distributed over an area of approximately 3 km 2 and at least six meteorite impact craters with a maximum diameter of about 100 m. The present paper reviews the most recent findings related to the meteorite, craters, processes of their formation, as well as the environmental effects of the impact in the Morasko area. The most important findings, reported in this review cover: 1) the recognition of two new minerals in the meteorite: moraskoite and czochralskiite; 2) the identification and detailed analysis of the ejecta layer around the craters and underlying paleosoil providing evidence for the mid-Holocene age of the impact; 3) the numerical modelling constraining the range of likely physical properties of the impactor, e.g. the diameter of the projectile forming the largest crater and its landing velocity (c. 1.5 m and 10 km/s, respectively);4) the studies of the nearby lake and peat deposits revealing restricted environmental effects of the impact. The Morasko craters field is currently one of the best-studied examples of small/moderate-sized meteorite impact in unconsolidated sediments.

Although the size-frequency distributions of icebergs can provide insight into how they disintegr... more Although the size-frequency distributions of icebergs can provide insight into how they disintegrate, our understanding of this process is incomplete. Fundamentally, there is a discrepancy between iceberg power-law size-frequency distributions observed at glacial calving fronts and lognormal sizefrequency distributions observed globally within open waters that remains unexplained. Here we use passive seismic monitoring to examine mechanisms of iceberg disintegration as a function of drift. Our results indicate that the shift in the size-frequency distribution of iceberg sizes observed is a product of fracture-driven iceberg disintegration and dimensional reductions through melting. We suggest that changes in the characteristic size-frequency scaling of icebergs can be explained by the emergence of a dominant set of driving processes of iceberg degradation towards the open ocean. Consequently, the size-frequency distribution required to model iceberg distributions accurately must vary according to distance from the calving front.

Environmental Earth Sciences, 2005

Tsunami sediments deposited in a coastal zone of Thailand by the 26 December 2004 tsunami wave we... more Tsunami sediments deposited in a coastal zone of Thailand by the 26 December 2004 tsunami wave were sampled within 50 days after the event. All surface and ground waters in tsunami- inundated zone revealed significant salinity at that time. The tsunami sediments, composed mainly of fine to medium sand, contain significantly elevated contents of salts (Na+, K+, Ca+2, Mg+2, Cl and SO 4−2) in water-soluble fraction, and of Cd, Cu, Zn, Pb in the bioavailable fraction and As in the exchangeable fraction in relation to the reference sample. The origin of contaminants is marine, as well as litho- and anthropogenic. The salts and Pb, Zn and Cu reveal high correlation to each other and to the mean grain size (pore size and porosity). Serious environmental hazard exists in that region because, due to gentle morphology, there is a risk of migration of the contaminants into ground waters and food chain.

DC resistivity soundings and geomorphological surveys have been carried out in the marginal zones... more DC resistivity soundings and geomorphological surveys have been carried out in the marginal zones and adjacent outwash plains of two glaciers in central Spitsbergen, Nor− wegian Arctic: Ebbabreen and Hörbyebreen. The study has revealed complex relationships between landforms, buried glacier ice and permafrost. From this work it is possible to dis− tinguish between moraine ridges which are ice−cored and those which are not. The latter oc− cur in areas which have possibly been affected by glacier surge. The active layer thickness was found to be 0.4 to 2.5 m for diamicton deposits (moraines) and 0.3 to 1.6 m in outwash glacifluvial sediments. The sediment infill thickness in valleys was determined to be as much as 20 m, thereby demonstrating that sandurs have important role in sediment storage in a glacial system. Typical resistivity values for sediment types in both the active layer and in permafrost were also determined.

The relationships between meteorological conditions, permafrost active layer thickness and therma... more The relationships between meteorological conditions, permafrost active layer thickness and thermal structure were studied for a dry, polar climate site, next to Petunia− bukta (central Spitsbergen), during four successive summer seasons (2000)(2001)(2002)(2003). In addi− tion to determination of the ground sedimentological and mineralogical properties, the fol− lowing parameters were measured: air temperature, air humidity (both at 2 m and 0.05 m above the ground), wind direction and velocity (at 2 m), precipitation, cloudiness, thickness of the permafrost active layer and ground temperature at 0.05, 0.1, 0.25, 0.5 and 0.75 m be− low the surface. The permafrost level was lowered 0.7 to 1.1 cm day −1 during days with tem− perature above freezing, reaching a maximum depth of 1.2 m. The temperature of the top 0.1 m of the ground reacted within one to two days to changes in air temperature. The reac− tion period of the ground temperature at 0.5 m was several days. Rainfall events were of mi− nor importance to thermal ground structure, in contrast to sites with a more marine climate. Other meteorological factors had a very small influence on the ground temperature. During summer, a well developed thermal gradient reaching over 12°C m −1 was observed, followed by isothermal conditions with temperature of 0°C at the beginning of fall, and reversal of the thermal gradient (−6.7°C m −1 ) in late fall. The interannual variations were mainly due to changes in summer temperature and to the length of period with snow cover in spring, which limited the beginning of thawing. The thermal structure of active layer is governed by seasonal conditions, regardless of overall climatic change.

Lab Laboratoria Aparatura Badania, 2008

Thirty-one metals and fifteen PAHs were examined in soils of central Spitsbergen, high Arctic. On... more Thirty-one metals and fifteen PAHs were examined in soils of central Spitsbergen, high Arctic. One of the world's northernmost human settlements and natural tundra were sampled to estimate the local human impact and its range. The contamination caused by local sources is significant only in the closest vicinity, and is usually at least an order of magnitude lower than European limits. The metal concentrations are closely related to bedrock geology and they are at similar levels as elsewhere in Svalbard. The long-distance transport of contaminants was not found at a significant level.

Environmental Earth Sciences, 2006

The 26 December 2004 tsunami covered significant portion of a coastal zone with a blanket of pote... more The 26 December 2004 tsunami covered significant portion of a coastal zone with a blanket of potentially contaminated sediments. In this report are presented results on mercury concentrations in sediments deposited by the tsunami in a coastal zone of Thailand. Since the total mercury concentrations are insufficient to assess mercury mobility and bioavailability in sediment, its fractionation was applied. Sediments were sampled within 50 days after the event and analyzed by sequential extraction method. The procedure of sequential extraction involved five subsequent stages performed with solutions of chloroform, deionized water, 0.5 M HCl, 0.2 M NaOH, and aqua regia. The mean concentration of total mercury in sediments was 119 ± 50 ng g−1 dry mass (range 66–230). The fractionation revealed that mercury is mainly bound to the least bioavailable sulphides 75 ± 6% (range 62–86), organomercury compounds 14 ± 7% (range 4–26), and humic matter 9 ± 7% (range 1–27). The lowest contributions bring fractions of water-soluble mercury 0.8 ± 1.0% (range 0.1–3.6) and acid soluble mercury 0.9 ± 0.5% (range 0.2–2.1). Although, the total mercury content is similar in a reference sample and in the tsunami sediments, the highly toxic organomercury fraction contribution is higher in the latter. The results were compared with chemical and sedimentological properties of the sediments but no significant correlations were obtained between them.

Acta Palaeobotanica, 2021

Lobelia dortmanna L. (Lobeliaceae family) is an indicator species that is predominantly found in ... more Lobelia dortmanna L. (Lobeliaceae family) is an indicator species that is predominantly found in oligotrophic and acidic lakes. They are mainly distributed in northwestern Europe. Their occurrence in Poland is highly threatened by the increasing grade of human activity and environmental eutrophication; however, new sites of Lobelia were discovered in the last few decades, for example, in Lake Krzywce Wielkie situated in Bory Tucholskie National Park (BTNP), Poland. The existence of Lobelia in this lake was unexpected because Cladium mariscus was also found in the lake. Cladium has different ecological demands and is regarded as a species typical of calcareous habitats where calcium is found in abundance in the substrate. To explain the coexistence of both species in Krzywce Wielkie, pollen analysis of organic sediments was performed for four short cores collected from the littoral zone of the lake and for one long deep-water core. Additionally, macrofossil analysis was done for all ...

Scientific Reports, 2020

Under conditions of global warming, organisms are expected to track their thermal preferences, in... more Under conditions of global warming, organisms are expected to track their thermal preferences, invading new habitats at higher latitudes and altitudes and altering the structure of local communities. To fend off potential invaders, indigenous communities/populations will have to rapidly adapt to the increase in temperature. In this study, we tested if decades of artificial water heating changed the structure of communities and populations of the Daphnia longispina species complex. We compared the species composition of contemporary Daphnia communities inhabiting five lakes heated by power plants and four non-heated control lakes. The heated lakes are ca. 3–4 °C warmer, as all lakes are expected to be by 2100 according to climate change forecasts. We also genotyped subfossil resting eggs to describe past shifts in Daphnia community structure that were induced by lake heating. Both approaches revealed a rapid replacement of indigenous D. longispina and D. cucullata by invader D. galeata immediately after the onset of heating, followed by a gradual recovery of the D. cucullata
population. Our findings clearly indicate that, in response to global warming, community restructuring may occur faster than evolutionary adaptation. The eventual recolonisation by D. cucullata indicates that adaptation to novel conditions can be time-lagged, and suggests that the long-term consequences of ecosystem disturbance may differ from short-term observations.

Przegląd Geologiczny, 2020

About 5,000 years ago near Morasko (the district of the present-day city of Poznañ, western Polan... more About 5,000 years ago near Morasko (the district of the present-day city of Poznañ, western Poland) the largest known iron meteorite shower in Central Europe took place. The evidence of that impact, documented so far, comprises numerous iron meteorite fragments distributed over an area of approximately 3 km 2 and at least six meteorite impact craters with a maximum diameter of about 100 m. The present paper reviews the most recent findings related to the meteorite, craters, processes of their formation, as well as the environmental effects of the impact in the Morasko area. The most important findings, reported in this review cover: 1) the recognition of two new minerals in the meteorite: moraskoite and czochralskiite; 2) the identification and detailed analysis of the ejecta layer around the craters and underlying paleosoil providing evidence for the mid-Holocene age of the impact; 3) the numerical modelling constraining the range of likely physical properties of the impactor, e.g. the diameter of the projectile forming the largest crater and its landing velocity (c. 1.5 m and 10 km/s, respectively);4) the studies of the nearby lake and peat deposits revealing restricted environmental effects of the impact. The Morasko craters field is currently one of the best-studied examples of small/moderate-sized meteorite impact in unconsolidated sediments.

Although the size-frequency distributions of icebergs can provide insight into how they disintegr... more Although the size-frequency distributions of icebergs can provide insight into how they disintegrate, our understanding of this process is incomplete. Fundamentally, there is a discrepancy between iceberg power-law size-frequency distributions observed at glacial calving fronts and lognormal sizefrequency distributions observed globally within open waters that remains unexplained. Here we use passive seismic monitoring to examine mechanisms of iceberg disintegration as a function of drift. Our results indicate that the shift in the size-frequency distribution of iceberg sizes observed is a product of fracture-driven iceberg disintegration and dimensional reductions through melting. We suggest that changes in the characteristic size-frequency scaling of icebergs can be explained by the emergence of a dominant set of driving processes of iceberg degradation towards the open ocean. Consequently, the size-frequency distribution required to model iceberg distributions accurately must vary according to distance from the calving front.

Environmental Earth Sciences, 2005

Tsunami sediments deposited in a coastal zone of Thailand by the 26 December 2004 tsunami wave we... more Tsunami sediments deposited in a coastal zone of Thailand by the 26 December 2004 tsunami wave were sampled within 50 days after the event. All surface and ground waters in tsunami- inundated zone revealed significant salinity at that time. The tsunami sediments, composed mainly of fine to medium sand, contain significantly elevated contents of salts (Na+, K+, Ca+2, Mg+2, Cl and SO 4−2) in water-soluble fraction, and of Cd, Cu, Zn, Pb in the bioavailable fraction and As in the exchangeable fraction in relation to the reference sample. The origin of contaminants is marine, as well as litho- and anthropogenic. The salts and Pb, Zn and Cu reveal high correlation to each other and to the mean grain size (pore size and porosity). Serious environmental hazard exists in that region because, due to gentle morphology, there is a risk of migration of the contaminants into ground waters and food chain.

DC resistivity soundings and geomorphological surveys have been carried out in the marginal zones... more DC resistivity soundings and geomorphological surveys have been carried out in the marginal zones and adjacent outwash plains of two glaciers in central Spitsbergen, Nor− wegian Arctic: Ebbabreen and Hörbyebreen. The study has revealed complex relationships between landforms, buried glacier ice and permafrost. From this work it is possible to dis− tinguish between moraine ridges which are ice−cored and those which are not. The latter oc− cur in areas which have possibly been affected by glacier surge. The active layer thickness was found to be 0.4 to 2.5 m for diamicton deposits (moraines) and 0.3 to 1.6 m in outwash glacifluvial sediments. The sediment infill thickness in valleys was determined to be as much as 20 m, thereby demonstrating that sandurs have important role in sediment storage in a glacial system. Typical resistivity values for sediment types in both the active layer and in permafrost were also determined.

The relationships between meteorological conditions, permafrost active layer thickness and therma... more The relationships between meteorological conditions, permafrost active layer thickness and thermal structure were studied for a dry, polar climate site, next to Petunia− bukta (central Spitsbergen), during four successive summer seasons (2000)(2001)(2002)(2003). In addi− tion to determination of the ground sedimentological and mineralogical properties, the fol− lowing parameters were measured: air temperature, air humidity (both at 2 m and 0.05 m above the ground), wind direction and velocity (at 2 m), precipitation, cloudiness, thickness of the permafrost active layer and ground temperature at 0.05, 0.1, 0.25, 0.5 and 0.75 m be− low the surface. The permafrost level was lowered 0.7 to 1.1 cm day −1 during days with tem− perature above freezing, reaching a maximum depth of 1.2 m. The temperature of the top 0.1 m of the ground reacted within one to two days to changes in air temperature. The reac− tion period of the ground temperature at 0.5 m was several days. Rainfall events were of mi− nor importance to thermal ground structure, in contrast to sites with a more marine climate. Other meteorological factors had a very small influence on the ground temperature. During summer, a well developed thermal gradient reaching over 12°C m −1 was observed, followed by isothermal conditions with temperature of 0°C at the beginning of fall, and reversal of the thermal gradient (−6.7°C m −1 ) in late fall. The interannual variations were mainly due to changes in summer temperature and to the length of period with snow cover in spring, which limited the beginning of thawing. The thermal structure of active layer is governed by seasonal conditions, regardless of overall climatic change.

Lab Laboratoria Aparatura Badania, 2008

Thirty-one metals and fifteen PAHs were examined in soils of central Spitsbergen, high Arctic. On... more Thirty-one metals and fifteen PAHs were examined in soils of central Spitsbergen, high Arctic. One of the world's northernmost human settlements and natural tundra were sampled to estimate the local human impact and its range. The contamination caused by local sources is significant only in the closest vicinity, and is usually at least an order of magnitude lower than European limits. The metal concentrations are closely related to bedrock geology and they are at similar levels as elsewhere in Svalbard. The long-distance transport of contaminants was not found at a significant level.

Environmental Earth Sciences, 2006

The 26 December 2004 tsunami covered significant portion of a coastal zone with a blanket of pote... more The 26 December 2004 tsunami covered significant portion of a coastal zone with a blanket of potentially contaminated sediments. In this report are presented results on mercury concentrations in sediments deposited by the tsunami in a coastal zone of Thailand. Since the total mercury concentrations are insufficient to assess mercury mobility and bioavailability in sediment, its fractionation was applied. Sediments were sampled within 50 days after the event and analyzed by sequential extraction method. The procedure of sequential extraction involved five subsequent stages performed with solutions of chloroform, deionized water, 0.5 M HCl, 0.2 M NaOH, and aqua regia. The mean concentration of total mercury in sediments was 119 ± 50 ng g−1 dry mass (range 66–230). The fractionation revealed that mercury is mainly bound to the least bioavailable sulphides 75 ± 6% (range 62–86), organomercury compounds 14 ± 7% (range 4–26), and humic matter 9 ± 7% (range 1–27). The lowest contributions bring fractions of water-soluble mercury 0.8 ± 1.0% (range 0.1–3.6) and acid soluble mercury 0.9 ± 0.5% (range 0.2–2.1). Although, the total mercury content is similar in a reference sample and in the tsunami sediments, the highly toxic organomercury fraction contribution is higher in the latter. The results were compared with chemical and sedimentological properties of the sediments but no significant correlations were obtained between them.