Debarya glyptosperma (De Bary) Wittrock 1872 (Zygnemataceae, Chlorophyta) as a possible airborne alga : a contribution to its palaeoeocological interpretation

This paper reports the fi nding of Debarya glyptosperma zygospores in xeric grasslands far from the natural habitat of algal species. This fact suggests that this species is an airborne alga and this has not been reported before. What is more the discoidal shape of the zygospores may dispose this taxon among the Zygnemataceae family towards air dispersion. This new information may assist in assessing it as an indicator of limnic conditions. However, the simple discovery of Debarya without any accompanying algal taxa and/or other water plants should not be conclusively interpreted as proof of the existence of water bodies because the zygospores might originate from distant transport

Exploring extreme brightness variations in blue supergiant MACHO 80.7443.1718: Evidence for companion-driven enhanced mass loss

Evolution of massive stars is dominated by interactions within binary systems. Therefore, it is necessary to investigate all forms of interaction in binary systems that may affect the evolution of the components. One of such `laboratories' is the massive eccentric binary system MACHO$\,$80.7443.1718 (ExtEV). We examine whether the light variability of the ExtEV can be explained by a wind-wind collision (WWC) binary system model. We conducted an analysis of broadband multi-color photometry of ExtEV, time-series space photometry from TESS, ground-based Johnson $UBV$ photometry, and time-series spectroscopy. We fitted an analytical model of light variations to the TESS light curve of ExtEV. We rule out the possibility of the presence of a disk around the primary component. We also argue that the non-linear wave-breaking scenario is not consistent with the observations of ExtEV. We refine the orbital parameters of ExtEV and find evidence for the presence of a tertiary component. Using evolutionary models we demonstrate that the primary component's mass is between 25 and 45$\,$M$_\odot$. We successfully reproduce light curve of ExtEV with our model, showing that the dominant processes shaping its light curve are atmospheric eclipse and light scattered in the WWC cone. We also estimate the primary's mass-loss rate due to stellar wind for $4.5\cdot 10^{-5}\,$M$_\odot\,{\rm yr}^{-1}$. ExtEV is not an extreme eccentric ellipsoidal variable, but an exceptional WWC binary system. The mass loss rate we derived exceeds theoretical predictions by up to two orders of magnitude. This implies that the wind in the system is likely enhanced by tidal interactions, rotation, and possibly also tidally excited oscillations. ExtEV represents a rare evolutionary phase of a binary system that may help to understand the role of a companion-driven enhanced mass loss in the evolution of massive binary systems.Comment: Submitted to Astronomy&Astrophysics, 23 pages, 15 figures, 9 table

Kettle-hole peatlands as carbon hot spots : Unveiling controls of carbon accumulation rates during the last two millennia

Funding Information: We would like to thank the anonymous reviewers for their comments that helped us to improve the manuscript. The research was funded by the National Science Centre (Poland), grant 2015/17/B/ST10/01656.Peer reviewe

Neodymium isotopes in peat reveal past local environmental disturbances

Funding The Stawek profile radiocarbon dating and investigation and neodymium measurements were financed by the National Science Centre, Poland, grants no. 2019/03/X/ST10/00849 and 2020/39/D/ST10/00641. The Głęboczek profile radiocarbon dating and investigation were financed by the National Science Centre, Poland, grant no. 2015/17/B/ST10/01656.Peer reviewedPublisher PD

Znaczenie wspólnych badań historycznych i paleoekologicznych nad wpływem człowieka na środowisko. Przykład ze stanowiska Kazanie we wschodniej Wielkopolsce

The aim of the article is to present the potential of interdisciplinary research on the human impact on the environment in the past on the example of a site in Greater Poland (Wielkopolska). It uses high-resolution palaeoecological analyses of peat archives from the Kazanie peat bog as well as archaeological and historical materials reflecting the settlement and economic activity of the inhabitants of Pobiedziska and surrounding villages throughout last 1200 years.Celem artykułu jest przedstawienie potencjału interdyscyplinarnych badań nad wpływem człowieka na środowisko w przeszłości na przykładzie Wielkopolski. Zostaną w nim wykorzystane wysokorozdzielcze analizy paleoekologiczne źródeł przyrodniczych wydobytych z torfowiska Kazanie oraz materiały archeologiczne i historyczne obrazujące osadnictwo i aktywność gospodarczą mieszkańców Pobiedzisk i okolicznych wsi w ciągu ostatnich 1200 lat

Znaczenie wysokorozdzielczych wielowskaźnikowych (multi-proxy) badań paleoekologicznych dla geografii historycznej i historii gospodarczej

The article presents the importance of palaeoecology for the study of economic history, historical geography and environmental history. The text introduces the methodological possibilities of palaeoecology. We pay attention to the unused potential of high resolution palaeoecology. By using natural archives (sediments of lakes and peatlands), we are able to trace the history of changes in nature. We can reconstruct history and better understand the changes in Poland’s ecosystems and its economic development.Artykuł prezentuje znaczenie paleoekologii dla badań historii gospodarczej, geografii historycznej i historii środowiskowej. Praca przybliża możliwości metodyczne paleoekologii. Zwracamy uwagę na niewykorzystany dotąd potencjał wysokorozdzielczej paleoekologii. Wykorzystując naturalne archiwa (osady jezior i torfowisk), jesteśmy w stanie prześledzić historię przemian przyrody, możemy zrekonstruować historię i lepiej zrozumieć zmiany ekosystemów Polski oraz jej rozwój ekonomiczny