Holocene Vegetation and Land Use History in the Northern Vosges (France)

A radiocarbon-dated peat profile from Rond Pertuis supérieure mire in the uplands of the Northern Vosges is studied using palynological methods. The profile dates from the middle Atlantic period (4500–3100 B.C.) to recent times. During the middle of the Atlantic period an oak forest rich in pine covered the Northern Vosges. Fir and beech immigrated at the end of the Atlantic leading to the decline of oak and pine in the forest. This also marked the onset of decisive human influence on the development of the terrestrial vegetation. Five land use phases were detected, the first one at the end of the Neolithic period (~4000–2200 B.C.). Subsequently, continuous land use is evident from the Bronze Age (2200–800 B.C.) up to now. In the late Middle Ages (A.D. 900–1500) and the early Modern Era (since A.D. 1500), the woodlands were completely altered by human activities. During the 19th century modern forestry introduced spruce into the investigated area in the Northern Vosges. Spruce afforestation then accelerated in the middle of the 20th century.researc

Holozäner Landschaftswandel im südlichen Oberrheintiefland und Schwarzwald

Die Untersuchungen zum holozänen Landschaftswandel im südlichen Oberrheintiefland und Schwarzwald konzentrieren sich auf die Zeitscheibe II (5500 bis 3000 v. Chr.) und III (1500 v. Chr. bis 500 n. Chr.) des DFG-Schwerpunktprogramms „Wandel der Geo-Biosphäre während der letzten 15 000 Jahre - Kontinentale Sedimente als Ausdruck sich ändernder Umweltbedingungen". Trotz einiger neolithischer Funde in den klimabegünstigten Lößgebieten wird der spürbare Eingriff des Menschen in die Naturlandschaft erst ab der Bronzezeit durch Kolluvien (Lößlehm) und Auensedimente nachgewiesen. Ein verstärkter Einfluß des Menschen auf die Abtragungsprozesse ist in der vorrömischen Eisenzeit, vor allem in der Latènezeit, zu beobachten. Die Ursachen dafür sind die Ausweitung der landwirtschaftlichen Nutzflächen durch die wachsende Bevölkerung bei gleichzeitiger Klimaverschlechterung. Eine einschneidende Auswirkung auf den Landschaftshaushalt hat bereits der Bergbau in der Latènezeit. Der anthropogene Einfluß auf die Geomorphodynamik verstärkt sich zur Römerzeit durch intensive landwirtschaftliche Nutzung, Siedlungen und den Bergbau. Mit dem Rückzug der Römer verringert sich die Siedlungsaktivität, und es tritt eine Stabilitätsphase mit Regeneration der Vegetation und Bodenbildung ein. Die alamannische Landnahme wirkte sich nur in den lößbedeckten und klimabegünstigten Siedlungsgebieten des Oberrheintieflandes und der Vorbergzone aus. Insgesamt führten die Aktivitäten der vorrömischen Eisenzeit und der Römerzeit zu den schwerwiegendsten anthropogenen Veränderungen im Untersuchungsgebiet während der drei Zeitscheiben.researc

A Late Würmian and Holocene pollen profile from Tüttensee, Upper Bavaria, as evidence of 15 millennia of landscape history in the Chiemsee glacier region

A late Würmian and Holocene pollen profile from Tüttensee near Chiemsee, Bavaria, covering 14 millennia of vegetation history, shows the late Würmian reforestation of the area, Holocene woodland development, and later the human impact on the landscape. In the early Holocene a distinct Ulmus phase preceded the Corylus and Quercus expansion. Afterwards, between 6000 and 4000 BCE, Picea was most common. The expansion of Fagus and Abies started at 4000 BCE, together with the decline of Ulmus. Fagus was more common than Abies. From 500 BCE Abies started to decline, Fagus has also declined from 1000 CE onwards. Before the modern times Picea/Pinus phase Quercus is prevailing. The prehistoric human impact is rather weak. A short reforestation phase at ~ 1 BCE – 1 CE hints at the rather complex migration history in this region with so called Celts, Germanic people and Romans involved. Strong human impact indicated by cereals, Plantago lanceolata, other human indicators and deforestation started at 900 CE

Earlier flowering of Betula pendula Roth in Augsburg, Germany, due to higher temperature, NO2 and urbanity, and relationship with Betula spp. pollen season

Flowering and pollen seasons are sensitive to environmental variability and are considered climate change indicators. However, it has not been concluded to what extent flowering phenology is indeed reflected in airborne pollen season locally. The aim of this study was to investigate, for the commonly represented in temperate climates and with highly allergenic pollen Betula pendula Roth, the responsiveness of flowering to different environmental regimes and also to check for commensurate changes in the respective pollen seasons. The region of Augsburg, Bavaria, Germany, was initially screened for birch trees, which were geolocated at a radius of 25 km. Random trees across the city were then investigated during three full flowering years, 2015–2017. Flowering observations were made 3–7 times a week, from flower differentiation to flower desiccation, in a total of 43 plant individuals. Data were regressed against meteorological parameters and air pollutant levels in an attempt to identify the driving factors of flowering onset and offset. Flowering dates were compared with dates of the related airborne pollen seasons per taxon; airborne pollen monitoring took place daily using a Hirst-type volumetric sampler. The salient finding was that flowering occurred earlier during warmer years; it also started earlier at locations with higher urbanity, and peaked and ended earlier at sites with higher NO(2) concentrations. Airborne pollen season of Betula spp. frequently did not coincide locally with the flowering period of Betula pendula: while flowering and pollen season were synchronized particularly in their onset, local flowering phenology alone could explain only 57.3% of the pollen season variability. This raises questions about the relationship between flowering times and airborne pollen seasons and on the rather underestimated role of the long-distance transport of pollen

Interdependence of sequential cytotoxic T lymphocyte and natural killer cell cytotoxicity against melanoma cells

Cytotoxic T lymphocytes (CTL) and natural killer (NK) cells recognize and eliminate cancer cells. However, immune evasion, downregulation of immune function by the tumour microenvironment and resistance of cancer cells are major problems. Although CTL and NK cells are both important to eliminate cancer, most studies address them individually. We quantified sequential primary human CTL and NK cell cytotoxicity against the melanoma cell line SK-Mel-5. At high effector-to-target ratios, NK cells or melan-A (MART-1)-specific CTL eliminated all SK-Mel-5 cells within 24 h, indicating that SK-Mel-5 cells are not resistant initially. However, at lower effector-to-target ratios, which resemble numbers of the immune contexture in human cancer, a substantial number of SK-Mel-5 cells survived. Pre-exposure to CTL induced resistance in surviving SK-Mel-5 cells to subsequent CTL or NK cell cytotoxicity, and pre-exposure to NK cells induced resistance in surviving SK-Mel-5 cells to NK cells. Higher human leucocyte antigen class I expression or interleukin-6 levels were correlated with resistance to NK cells, whereas reduction in MART-1 antigen expression was correlated with reduced CTL cytotoxicity. The CTL cytotoxicity was rescued beyond control levels by exogenous MART-1 antigen. In contrast to the other three combinations, CTL cytotoxicity against SK-Mel-5 cells was enhanced following NK cell pre-exposure. Our assay allows quantification of sequential CTL and NK cell cytotoxicity and might guide strategies for efficient CTL–NK cell anti-melanoma therapies