Chironomidae-inferred anthropogenic and natural processes in moat and palaeochannel systems − Rozprza case study

Celem pracy jest paleoekologiczna rekonstrukcja środowiska w rejonie stanowiska archeologicznego w Rozprzy (woj. łódzkie), na podstawie analizy subfosylnych zgrupowań Chironomidae (Diptera). Zmienność zgrupowań Chironomidae w późnym glacjale zbadano z wykorzystaniem profilu jeziornego pobranego z paleomeandru rzeki Luciąży. Odtworzono średnie temperatury lata i zmiany hydrologiczne w okresie ok. 13 300 – 12 200 lat cal. BP, wraz z jednym z pierwszych dobrze udokumentowanych stwierdzeń chłodnej oscylacji interallerødzkiej w Europie Środkowo-Wschodniej. Stosunkowo wysokie temperatury lata (do 16˚C) w młodszym dryasie mogą wskazywać na lokalnie cieplejsze warunki pod koniec zlodowacenia wisły bądź wysoki stopień kontynentalizmu w tym stadiale w Polsce środkowej. Wyniki analiz Chironomidae umożliwiły rekonstrukcję zmian siedliskowych w paleostarorzeczu i fosie, wchodzącej w skład kompleksu późnośredniowiecznego gródka. W zbiorniku sztucznym (fosa) wykazano znacznie szybsze tempo paludyfikacji niż w starorzeczu. W naturalnych zbiornikach zgrupowania Chironomidae były kształtowane głównie przez globalne i regionalne zmiany klimatyczne. W fosie determinantami występowania i składu Chironomidae były lokalne zmiany siedliskowe, takie jak zmiany trofii wody oraz przepłukiwanie fosy. Analiza osadów organicznych z czterech rdzeni pobranych w obrębie systemu fos, pozwolił na scharakteryzowanie zmian siedliskowych w czasie i przestrzeni. Nawet w tak małym i płytkim zbiorniku, tempo i zakres procesów ekologicznych nie były równomierne. Zróżnicowanie fosy zależało głównie od głębokości dna, ekspozycji na procesy denudacyjne i zaopatrzenia w świeżą wodę. W pracy przedstawiono również wyniki analizy grup morfologicznych i troficznych Chironomidae, będącej pierwszym etapem badań nad wykorzystaniem ich cech funkcyjnych w paleoekologii. Udowodniono, że morfo-taksonomia może być wykorzystywana do rekonstrukcji zmian siedliskowych w podobnym stopniu, jak gildie troficzne.This work was supported by National Science Centre grant [DEC-2013/11/B/HS3/03785] and Faculty of Biology and Environmental Protection, University of Lodz subsidies of for young scientists [B1711000001557.02, B1811000001847.02, B1911000002143.02

The optimal time for sampling macroinvertebrates and its implications for diversity indexing in rheocrenes − case study from the Prokletije Mountains

In most studies, sampling of springs has typically been undertaken over one season, which has raised the question what the most suitable time(s) to undertake sampling is. In this study, we report the results of macroinvertebrate monthly samplings performed in two springs in western Kosovo in order to determine the most appropriate time to undertake sampling to characterise biodiversity. Diversity indices have revealed that insect assemblages remain more diverse than assemblages of fully aquatic invertebrates. The results of SIMPER have revealed that winter communities remain the most dissimilar one another and also to other seasons. However, when Gammarus balcanicus is excluded, this pattern becomes blurred. To sum up, our results illustrate that (1) multiple surveys covering more than one season provide a comprehensive picture of total biodiversity, and (2) for appropriate characterising of the macroinvertebrate community in the studied rheocrenes at least winter and summer were required

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

The optimal time for sampling macroinvertebrates and its implications for diversity indexing in rheocrenes − case study from the Prokletije Mountains

In most studies, sampling of springs has typically been undertaken over one season, which has raised the question what the most suitable time(s) to undertake sampling is. In this study, we report the results of macroinvertebrate monthly samplings performed in two springs in western Kosovo in order to determine the most appropriate time to undertake sampling to characterise biodiversity. Diversity indices have revealed that insect assemblages remain more diverse than assemblages of fully aquatic invertebrates. The results of SIMPER have revealed that winter communities remain the most dissimilar one another and also to other seasons. However, when Gammarus balcanicus is excluded, this pattern becomes blurred. To sum up, our results illustrate that (1) multiple surveys covering more than one season provide a comprehensive picture of total biodiversity, and (2) for appropriate characterising of the macroinvertebrate community in the studied rheocrenes at least winter and summer were required

The spatial and temporal reconstruction of a medieval moat ecosystem

Abstract Moats and other historical water features had great importance for past societies. The functioning of these ecosystems can now only be retrieved through palaeoecological studies. Here we aimed to reconstruct the history of a stronghold’s moat during its period of operation. Our spatio-temporal approach allowed mapping of the habitat changes within a medieval moat for the first time. Using data from four cores of organic deposits taken within the moat system, we describe ecological states of the moat based on subfossil Chironomidae and Ceratopogonidae assemblages. We found that over half (57%) of the identified dipteran taxa were indicative of one of the following ecological states: limnetic conditions with or without periodic water inflow, or marshy conditions. Samples representing conditions unfavourable for aquatic insects were grouped in a separate cluster. Analyses revealed that the spatio-temporal distribution of midge assemblages depended mostly on depth differences and freshwater supply from an artificial channel. Paludification and terrestrialization did not happen simultaneously across the moat system, being greatly influenced by human activity. The results presented here demonstrate the importance of a multi-aspect approach in environmental archaeology, focusing not only on the human environment, but also on the complex ecology of the past ecosystems

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

The Warta River valley was greatly influenced by the ice sheet of the Last Glacial Maximum (LGM). A small peatland located in the Warta drainage system is here used as a palaeoarchive of climatic and habitat changes during the Late Glacial (Weichselian). The Ługi sediment profile was investigated using multi-proxy (pollen, Chironomidae, Cladocera and geochemistry) analyses that recorded changes in a fluviogenic sedimentary depression. After the Poznań Phase (LGM), Ługi functioned as an oxbow lake that was cut off from the active river channel as a result of fluvial erosion. Since that time, the Warta River has flowed only along the section now occupied by the Jeziorsko Reservoir. Sedimentation of lacustrine deposits started at the beginning of the Late Glacial. Summer temperature reconstructions indicate cool Oldest and Younger Dryas, but no clear cooling in the Older Dryas. During the Younger Dryas the palaeolake was completely occupied by a peatland (fen), which periodically dried out during the Holocene. Investigation of this site has tracked the reaction of the habitat to climatic, hydrological and geomorphological changes throughout the Late Weichselian

The environmental history of the oxbow in the Luciąża River valley – Study on the specific microclimate during Allerød and Younger Dryas in central Poland

The vicinity of the Rozprza archaeological site (central Poland) has been the area of a series of palaeoecological studies tracking the environmental history of the Luciąża River valley up to ca. 13,200 cal. BP. Numerous subfossil palaeomeanders of different sizes have been discovered in the valley floor. Here, we present the first results of multiproxy research on the paleo-oxbow lake fill, one of the oldest in the region. The wide range of palaeoecological analyses resulted in reconstructions of vegetation history, climatic, hydrological and habitat changes. The studied oxbow was an aquatic ecosystem with diverse invertebrate fauna until the end of Younger Dryas when it transformed into a limno-telmatic habitat. The sediment composition indicates active denudation processes and several episodes of turbulent hydrological conditions. Such an increased river activity could have caused flooding, resulting in an allochthonous matter supply to the oxbow lake in Late Vistulian. Environmental changes were strictly related to the regional features of the catchment, the transformation of soils, and the hydrogeological conditions. The chironomid- and pollen-inferred climatic reconstructions indicate periods of high and low continentality. The chironomid record indicates relatively cool summer conditions in the Allerød, especially ca. 13,000 cal. BP, possibly related to the Gerzensee Oscillation. On the other hand, a distinct increase of summer temperatures in Younger Dryas (up to 16 °C) was recorded. Such a situation was also confirmed in some other studies from the region, suggesting that it might be the effect of some specific, local palaeoclimatic conditions.Fundator badań: Fundator badań: Optional.empt