Evolution Of Vegetation, Relief And Geology In Central Poland Under Anthropopressure

Published in: Origin of Relief of Central Poland and Its Anthropogenic Transformation in Łódź University Geographical Research, edited by. E.Kobojek, T.MarszałThe review of the localities with biogenic, slope, fluvial and aeolian deposits in which the indirect impact of human activity on their ori gin is recorded, shows that evidence of changes of the vegetation pat tern and evolution of the relief and geological structure are in Central Poland particularly numerous. The exact correlation of the sites is beyond the scope of this chapter, due to the strictly local nature of prehistoric anthropopressure and a variety of environmental condi tions. Nevertheless it is possible to draw some general remarks. 1. More significant changes in the relief and geology of Central Poland that occurred under human pressure date back to the Neo holocene (the Early Subboreal Period and Subatlantic Period). More pronounced transformation of the slopes, river valley bottoms and aeolian landforms occurred since the Middle Bronze Age, around 3500 years ago. 2. The punctuated changes, in both vegetation and abiotic com ponents of the environment, were marked at the earliest in the large river valleys (e.g. Warta, Ner, Bzura rivers) and minor valleys within the Warsaw-Berlin pradolina. In higher lying parts of Central Po land, these changes on a similar scale emerged much later, only after ca. 2000–2500 years. It was connected with much worse conditions for the settlements in areas of more diversified relief configuration, with poorer soils and limited access to water. 3. The transformation of the vegetation, relief and geological structure took place gradually, along with the expansion of prehis toric settlement of the Trzciniec Culture , the Lusatian Culture and the Przeworsk Culture, whereas in the historical period – along with Early Medieval settlement. Less important for these changes were the impact of people of the Neolithic cultures, and short-stay of peo ple of the Pomeranian Culture in the Central Poland area. 4. The studied transformations were driven by both natural factors, particularly climate, which has changed during the Holo cene repeatedly (but on a relatively moderate scale), and by anthro pogenic factors, the importance of which was growing rapidly in the expansion phases of prehistoric cultures. These influences are rela tively easy to distinguish in the palynological profiles by a well-de fined group of plants accompanying the settlement and economy, whereas their distinguishing in the relief and geology transforma tions is much more difficult. However, it should be stressed that the development of the slopes and aeolian geosystems, and superim posing increased fluvial activity, in many cases were synchronous. This synchronous response, noting at the same time in different sed imentary environments, rather indicates the dominance of anthro pogenic factor, because the humid climate, favourable to stimulate fluvial and slope processes is less favourable for the simultaneous development of aeolian relief. Favourable natural conditions un doubtedly facilitated breaking the balance of the geosystem and the initiation of processes and their more efficient course under anthro pogenic changes of the environment. 5. The trends of the Neoholocene relief transformations were very different. Both processes, leading to local increases of relief and diversified terrain morphology (e.g. gully erosion, so-called wheel erosion, formation of agricultural terraces, accumulation of series overlaying of Late Glacial dunes) and the processes of op posite trends (e.g. aggradation of valley bottoms, tillage erosion, dismant ling of old dunes). Most Neoholocene morphogenetic pro cesses resulted in the increased lithological differentiation, soil for mation and increasing geodiversity of the environment. 6. A number of processes that affected the nature of the vegeta tion, relief and geology was a targeted, intentional and direct inter ference (e.g. land clearance in order to obtain arable fields, energy raw materials and building materials, construction of embankments in river valleys, exploitation of till, sand and other aggregates). How ever, most of the changes should be regarded as unintended and negative, so to speak, a side effect of centuries of settlement and economy. There may be mentioned here: planation of slopes used for agriculture, gully erosion, wheel erosion, the spread of poor aeo lian areas or the increase in the frequency and scale of floods in the Central Poland rivers as a result of an accelerated water circulation on the vegetation-free slopes. 7. Obviously, the Holocene morphogenetic cycle occurred in the past (and is still occurring) under human impact, which proves the J. Dylik’s thesis quoted in the Introduction. This cycle, superim posed on the periglacial morphogenesis, partially obliterates its ef fects and partially only modifies them. Taking into account the short duration of the Holocene cycle, it is characterised by a large dynam ics of the processes being accelerated and intensified by man

Late Glacial organic sediments in palaeogeographical reconstructions (cases from the Łódź region)

Late Glacial organic succession is recorded at the Żabieniec and Koźmin Las sites, in the Łódź region. A multiproxy approach provides a palaeogeographical assessment and yields a new insight into the old morainic area of the Polish Lowland. Additionally, the key profile Witów contributes in the reconstruction. It is demonstrated that the Late Glacial organic sediments of the Łódź region contain signs of environmental changes, starting from the first warming just after the Weichselian ice-sheet retreat from the Polish territory. Records at Żabieniec, apart from registering biotic and abiotic conditions which influenced functioning of a peatbog, provides information on the permafrost behaviour throughout the Late Glacial. At Koźmin Las, a unique discovery of the in situ riparian forest accompanied by organic sediments led to a high-resolution study of a series of events taking place on the floodplain during the Younger Dryas

RECORDS ON ANTHROPOGENIC ENVIRONMENTAL CHANGES IN SMALL RIVER VALLEYS IN THE VICINITY OF ŁOWICZ (CENTRAL POLAND): THEIR SIGNIFICANCE FOR THE RECONSTRUCTION OF LATE HOLOCENE SETTLEMENT TENDENCIES

Based on palaeobotanical analyses of organic deposits, as well as geomorphological and geological studies at four sites in various geomorphological locations in relation to tributaries of the Bzura River, the presence of traces of human activity, its intensiveness, and classification to cultural levels were analysed. A pattern of later and later settlement in areas remote from the axis of the Warsaw–Berlin streamway was observed along with the gradual introduction of settlement from river valley bottoms to watershed zones

Limnic past of peatlands in the Łódź Region

Studies of infills of present-day peatland basins of the Łódź Region revealed the presence of lacustrine sediments underlying peats. They usually rest on mineral bottoms of basins, and their accumulation began in the Late Vistulian and continued in the Holocene. Out of 17 objects subjected to geological and palaeoecological examinations such arrangement was found in 8 of them. In the locality of the Żabieniec peatland 16.4 m of biogenic sediments was documented. The essential part of the profile contains detrital gyttja (at the bottom – detrital-clay gyttja, above – fine detrital gyttja). Within the Ner-Zawada peatland the thickness of biogenic sediments is 4.70 m and lake sediments are represented by clay- calcareous gyttja and calcareous gyttja. The thickness of biogenic sediments in the Ługi peatland reaches to 2.90 m. At this locality detrital- calcareous gyttja and detrital gyttja accumulated on the mineral substratum. In the Rąbień peatland basin the thickness of lacustrine sediments and peat reaches 6.2 m; on sandy bottom rest detrital-clay gyttja and detrital gyttja. In the Silne Błoto-Witów peatland only the 3.5 m long profile of the so- called “west island” contains lacustrine deposits covered by herbaceous peat. In the bottoms of a few other peatlands of the region, biogenic lake deposits were found, but their thickness is small (such as Korzeń, Bęczkowice, Parchliny). Therefore it may be assumed that some peatlands of the Łódź Region are of limnic origin. The presented examples of lake sediment series in the basins of contemporary peatlands in the Łódź Region allow to conclude that during the last fifteen thousand years, lakes occurred in this area, not only in numerous oxbow basins, but also in plateau depressions and aeolian landforms. Lake basins were more frequent during the late Vistulian, and survived in the Holocene until the Subboreal period. All water bodies of wetlands of the Łódź Region, except for oxbows, which are observed today, are of an anthropogenic origin.Analiza wypełnień mis współczesnych torfowisk regionu łódzkiego wykazała pod torfami obecność osadów jeziornych. Zalegają one zwykle na mineralnym dnie mis, a ich akumulacja rozpoczęła się w późnym vistulianie i trwała jeszcze w holocenie. Spośród 17 obiektów poddanych szczegółowym badaniom geologicznym i paleoekologicznym taki układ osadów stwierdzono w ośmiu z nich. W misie torfowiska Żabieniec udokumentowano 16,4 m osadów biogenicznych, a zasadniczą część profilu stanowi gytia detrytusowa (w dolnej części detrytusowo-ilasta, a powyżej gytia drobnodetrytusowa i grubodetrytusowa). W obrębie torfowiska Ner-Zawada miąższość osadów biogenicznych wynosi 4,70 m, a osady jeziorne reprezentują: gytia ilasto-wapienna i gytia wapienna. Miąższość osadów biogenicznych w obrębie torfowiska Ługi sięga 2,90 m, na mineralnym podłożu zalega gytia detry- tusowo-wapienna i gytia detrytusowa. W torfowisku Rąbień miąższość torfu i podścielających go osadów jeziornych sięga 6,2 m, na piaszczystym podłożu zalegają: gytia detrytusowo-ilasta i gytia detrytusowa. Torfowisko Silne Błoto-Witów dokumentuje jedynie profil z tzw. wyspy zachodniej o miąższości 3,5 m prezentujący głównie osady jeziorne, przykryte przez torf zielny. W podłożu torfów kilku innych torfowisk regionu stwierdzono biogeniczne utwory jeziorne, ale ich miąższość jest niewielka (m.in.: Korzeń, Bęczkowice, Parchliny). Uznać więc należy, że część torfowisk regionu łódzkiego ma pochodzenie limnogeniczne. Zaprezentowane przykłady serii osadów jeziornych w misach współczesnych torfowisk regionu łódzkiego pozwalają stwierdzić, że w trakcie ostatnich 15 tysięcy lat jeziora występowały na tym obszarze nie tylko w licznych starorzeczach, ale także w obniżeniach wysoczyznowych i wśród form eolicznych. Zbiorniki jeziorne funkcjonowały liczniej w okresie późnego vistulianu, a w holocenie przetrwały aż do okresu subborealnego. Wszystkie zbiorniki wodne na obszarach mokradeł regionu łódzkiego, poza starorzeczami, obserwowane współcześnie, mają charakter antropogeniczny

Multiproxy study of anthropogenic and climatic changes in the last two millennia from a small mire in central Poland

The Żabieniec kettle hole is the first peatland in central Poland analyzed quantitatively with four biotic proxies (plant macrofossils, pollen, testate amoebae and chironomids) to reconstruct the past environmental change. Palaeoecological data were supported by historical and archaeological records. We focused on autogenic vegetation change and human impact in relation to climatic effects. The aims of our study were (a) to describe the development history of the mire during the last 2,000years, (b) to date and reconstruct the anthropogenic land-use changes and (c) to discuss a possible climatic signal in the peat archive. The combination of proxies revealed dramatic shifts that took place in the peatland since the Roman Period. Żabieniec was a very wet telmatic habitat until ca. AD 600. Then, the water table declined, and the site transformed into a Sphagnum-dominated mire. This dry shift took place mainly during the Early Medieval Period. Human impact was gradually increasing, and it was particularly emphasized by deforestation since AD 1250 (beginning of the Late Medieval Period). Consequently, surface run-off and aeolian transport from the exposed soils caused the eutrophication of the mire. Furthermore, chironomids and testate amoebae reveal the beginning of a wet shift ca. AD 1350. Openness considerably increased in the Late Medieval and the Modern Periods. The highest water table during the last 1,000years was recorded between AD 1500 and 1800. This wet event is connected with deforestation, but it could be also associated with the Little Ice Age. Our study shows plant succession in the Żabieniec peatland, which can be explained with the recent landscape transformation. However, such changes are also possibly linked with the major climatic episodes during the last two millennia, such as the Medieval Warm Period and the Little Ice Ag

Changes in habitat conditions in a Late Glacial fluviogenic lake in response to climatic fluctuations (Warta River valley, central Poland)

The Warta River val ley was greatly in flu enced by the ice sheet of the Last Gla cial Max i mum (LGM). A small peatland lo cated in the Warta drain age sys tem is here used as a palaeoarchive of cli ma tic and hab i tat changes dur ing the Late Gla cial (Weichselian). The ugi pound sed i ment pro file was in ves ti gated us ing multi-proxy (pol len, Chironomidae, Cladocera and geo chem is try) anal y ses that re corded changes in a fluviogenic sed i men tary de pres sion. Af ter the Poznan Phase (LGM), ugi pound func tioned as an ox bow lake that was cut off from the ac tive river chan nel as a re sult of flu vial ero sion. Since that time, the Warta River has flowed only along the sec tion now oc cu pied by the Jeziorsko Res er voir. Sed i men ta tion of lac us trine de pos its started at the be gin ning of the Late Gla cial. Sum mer tem per a ture re con struc tions in di cate cool Old est and Youn ger Dryas, but no clear cool ing in the Older Dryas. Dur ing the Youn ger Dryas the palaeolake was com pletely oc cu pied by a peatland (fen), which pe ri od i cally dried out dur ing the Ho lo cene. In ves ti ga tion of this site has tracked the re ac tion of the hab i tat to cli ma tic, hy dro log i cal and geomorphological changes through out the Late Weichselian.Peer reviewe

Multi-proxy inferred hydroclimatic conditions at Bęczkowice fen (central Poland); the influence of fluvial processes and human activity in the stone age

Fens have been forming in the river valleys of central Poland since the Bølling and went through a transformation from fully aquatic to semiterrestrial habitats during the Younger Dryas/Holocene transition. This drove plant and invertebrate communities and left a distinct pattern in chemical sediment composition, which is why river valley peatlands are sensitive palaeo-archives of climatic, hydrological and edaphic changes. Here we reconstruct the Late Weichselian history of the Bęczkowice fen in the upper Luciąża River valley using geochemical, pollen, Cladocera and Chironomidae proxies. Pollen-based age estimation indicates that the analysed peat sequence dates from the Bølling to Early Holocene. The layers 190-170 cm and 125-105 cm of the studied core were reworked by fluvial processes. Chironomidae and Cladocera communities indicate mostly limnetic conditions during the Allerød and early Younger Dryas. Peatland pools were supplied mostly by Luciąża River floods, but also by groundwater. Since the onset of the Holocene, the water level has dropped, eliminating aquatic midges and water fleas, and supporting taxa typical of astatic waters and wet soil.Peer reviewe

Chronostratigraphy of the late Vistulian in central Poland and the correlation with Vistulian glacial phases

The Vistulian decline was a period of rapid environmental events. The authors correlated ages of the last Scandinavian Ice Sheet limits in northern Poland with ages of prominent events adapting the conditions of periglacial environment of Central Poland in response to the Late Vistulian climate warming. Ages from previous thematic geological and palaeogeographical studies were collected. The approach used indicates that despite methodological uncertainties and sometimes inconsistency of ages, it is especially helpful in timing of first warming signals (ca. 19–18 cal ka BP) and establishing of environmentally bipartite 3 millennia of the Oldest Dryas in the extraglacial zone. Abrupt warming at the onset of the Bølling-Allerød is well registered in biotic and abiotic archives available from Central Poland and remains in agreement with the large recession of the southern ice sheet margin