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In the context of a practical course that is required for 2nd year students who aim to achieve a Bachelor's degree in Psychology, we will conduct a replication study of “The context-specific proportion congruent stroop effect: Location as a contextual cue” by MATTHEW J. C. CRUMP, ZHIYU GONG, and BRUCE MILLIKEN.

Past temperature records are key tools for inferring climate dynamics and provide empirical data for testing climate models to improve our mechanistic understanding of natural climate variability. Unfortunately, very few quantitative records of pre-historic continental temperatures exist in Europe. Moreover, existing paleothermometers mainly provide mean annual or warm season temperatures, limiting our understanding of climate variability during the transitional seasons and winter. Alkenones are temperature-sensitive lipids produced by Isochrysidales algae, which have been used for decades to reconstruct quantitative changes in sea-surface temperatures. In lakes, they are not ubiquitous, but they have been increasingly reported in both saline and freshwater lakes worldwide, suggesting that there is great potential for alkenone-based paleotemperature reconstructions in lacustrine settings. Lacustrine alkenones have already been successfuly used to reconstruct paleotemperatures in high-latitude lakes. Depending on the timing of ice-out, they record winter/spring or summer temperatures. In our study, we found that a significant number of Swiss lakes contain lacustrine alkenones. Other studies in mid-latitude European lakes suggest that the peak of alkenone production occurs in spring. The monitoring of Lake St Moritz, an alpine lake in the South East of Switzerland, will allow determining the seasonality of alkenone production in mid-latitute high altitude lakes. Combining genetic analyses and the monitoring of physico-chemical parameters will provide more information about the ecology of the alkenone producers. Our first results suggest that we will be able to improve the understanding of alkenone production in freshwater lakes and to develop the first spring lake temperature reconstruction in Switzerland that extends beyond existing historical records., EGUsphere

13th European Diatom MeetingProgress in Diatom Biogeography: Explanations for Microbial Endemism2-4 March 2021Amgueddfa Cymru – National Museum Wales, Previous studies show that climate variability and volcanism along with the arrival of humans played a significant role in the recent evolution of insular Azorean ecosystems. However, the timing and rate of anthropogenic impacts are poorly understood. Paleolimnological research allows us to reconstruct ecological conditions prior to and after human settlement on oceanic islands, to understand how species and island ecosystems responded to both natural and anthropogenic disturbances. Here, we present the first high-resolution reconstruction of ecological changes in Lake Funda (Flores Island, Azores) over the last millennium based on diatom analysis from a 993 cm-long sediment core retrieved in June 2017. The chronology of the reconstructed paleoenvironmental events has been established with a preliminary radiocarbon-based age model. The three main ecological periods were mostly related to human disturbance. (1) During the pre-human arrival period (AD 950 to 1330), the sediment record has a diverse benthic and tychoplanktonic diatom assemblage dominated by Staurosirella pinnata and Pseudostaurosira elliptica, representing the baseline conditions of Lake Funda. (2) Upon human arrival in Flores, around AD 1330, human disturbances in the catchment area (e.g., livestock release and gradual forest clearance) and climate fluctuations led to changes in the diatom assemblage. Several climate fluctuations from AD 1330 to 1560 and the onset of human-driven deforestation (ca. 1380 AD) led to an abrupt drop in diatom diversity and the dominance of eutrophic Aulacoseira spp.. (3) Finally, the most recent period (AD 1560 to 2008) corresponds to the well-established Portuguese settlement in Flores Island. Complete forest clearance led to a second ecological perturbation characterized by a highly productive lake with an anoxic hypolimnion and enhanced in-lake nutrient recycling. From 1980, changes in diatom assemblages suggest prolonged periods of summer stratification and increase in extreme climatic events, which could be associated with recent climate change. The synergistic influence of multiple environmental stressors (climate and anthropogenic) may have resulted in major shifts in the diatom assemblages of Lake Funda. This study increases our understanding of how the interplay between climate and anthropogenic factors results in drastic shifts in lake ecosystems. The present paleolimnological approach has important implications for long-term ecosystems conservation management in remote volcanic oceanic islands. This research is funded by DISCOVERAZORES (PTDC/CTA-AMB/28511/2017; DL57/2016/ ICETA/EEC2018/25) and through the funded research project PaleoModes (CGL2016-75281-C2) and the Luso-American Foundation's "Crossing the Atlantic" program., This research is funded by DISCOVERAZORES (PTDC/CTA-AMB/28511/2017; DL57/2016/ ICETA/EEC2018/25) and through the funded research project PaleoModes (CGL2016-75281-C2) and the Luso-American Foundation's "Crossing the Atlantic" program.

Since the Portuguese settlement of the Azores Archipelago in the 15th century humans have extensively modified the Azorean landscape, with exotic plants dominating the present-day vegetation and eutrophication in numerous lakes. However, it is uncertain whether hydroclimate variability contributed to changes in terrestrial and aquatic ecosystems and helped facilitate the arrival of humans in the Azores. To assess the role of climate in these processes, we developed complementary paleoecological and paleoclimate records from Lake Funda on Flores Island that span the last millennium. Low variability in precipitation amount, as recorded by leaf wax hydrogen isotopes (¿Dwax) from C30 fatty acids, suggests that the hydroclimate on Flores Island was relatively stable between c. 1000-1350 CE and drier between c. 1350-1450 CE when Portuguese explorers arrived in Flores Island (1452 CE). More depleted ¿Dwax values between c. 1450-1650 CE suggest wetter climate conditions may have contributed to the slow establishment of permanent settlements on Flores Island. Major changes in n-alkane average chain lengths (ACL27-33) and 5ß-stigmastanol indicate that major shifts in vegetation composition and the widespread introduction of livestock, respectively, took place over c. 100-years between c. 1500-1600 CE. Landscape changes were followed by a decrease in ¿15N as N2-fixation by cyanobacteria increased in Lake Funda. Around the same time, increases in the ratio of 5¿(H)-stanols/¿5-sterols suggest that the lake bottom water was more frequently experiencing reducing, i.e. hypoxic, conditions, thereby enhancing in-lake phosphorous cycling and increasing the lake trophic state. Evidence of eutrophication in Lake Funda persisted during the Little Ice Age despite increased variability in ¿Dwax between c. 1650-1850 CE, highlighting continued human impacts on the lake ecosystem. Reforestation efforts on Flores Island and a drier climate in the 20th century most likely reduced nutrient leaching and soil erosion in the catchment area of Lake Funda, yet eutrophication continues to be a problem. This research is funded by through the research projects PaleoModes (CGL2016-75281-C2) and DISCOVERAZORES (PTDC/CTA-AMB/28511/2017) and the Luso-American Foundation.

20th Congress of the International Union for Quaternary Research (INQUA) in Dublin, Ireland, 25-31 july 2019, Human settlement of uninhabited land masses can dramatically transform local ecosystems and its endemic biota around the world. These changes are particularly evident on islands, where human settlement usually marked a period of large-scale habitat destruction and extinctions of local flora and fauna. Historical records specify that the Azores archipelago in the North Atlantic Ocean was settled in the mid-15th century CE. The human footprint in the Azores was large and widespread: within six centuries of colonization more than 95% of the original native forests were destroyed. Paleoecological and geochemical reconstructions from the Azores have allowed us to compare ecosystem processes and dynamics before and after colonization. To document the cultural evolution of human settlement in the Azores archipelago, we studied lake sediment records from four distant islands, located in the Western (Flores), Central (Pico and Terceira) and Eastern (São Miguel) group of islands. In particular, we investigated the role of the Medieval Warm Period and the Little Ice Age climatic periods as external driving forces for human displacement and potential triggers for cultural transformations. A suite of proxies – pollen, diatoms, chironomids, cladocerans, hydrogen isotopes, macroscopic charcoal, organic matter, inorganic composition (XRF scanning and X-ray diffractions), and lithofacies – were used to distinguish between different signals of climate change, landscape and ecosystem dynamics, and their local lacustrine responses. A comprehensive multi-disciplinary analysis of all the proxies provides strong indications that the Azores were colonized more than two centuries earlier than currently recognised. These early colonizers first reached the Central group of islands around 1100 yr CE and the Eastern group before the end of the 13th Century. The Western group was subsequently reached around 1300 yr CE. Early human activities included the introduction of domestic animals, land clearance and small-scale agriculture, and extractive forestry mostly for charcoal production. The origin of the early colonizers is further discussed during the presentation., This research is funded by the Juan de la Cierva-formación postdoctoral grant (FJCI-2015-26199), the Fundação LUSO-Americana, Crossing the Atlantic Program, and through the funded research projects PaleoNAO (CGL2010-15767), RapidNAO (CGL2013-40608-R), PaleoModes (CGL2016-75281-C2) and DISCOVERAZORES (PTDC/CTA-AMB/28511/2017).

Third International Conference on Island Ecology, Evolution and Conservation in University of La Reunión Saint Denis, France, 8-13 July 2019, The discovery and colonization of islands are crucial to understand the colonization patterns of new territories, the spread of languages, past economic trade, difiusion of past societal and knowledge during the past millennium. However, historical and archaeological records are scarce and incomplete on many islands, including the Azores, hampering the determination of the exact age of first human settlements. The most commonly accepted date for the first settlement on the Azores islands based on historic documents is 1432 A.D. However, a recent environmental reconstruction of S~ao Miguel island that covers the last 730 years clearly shows that the first-settlements of this island took place by ca. 1287 A.D., approximately 150 years prior to the currently recognized colonization. Here we present a new perspective, using both classical (e.g. pollen and spores from higher plants, fungal spores, algae remains, charcoal particles, plant and animal fragments) as well as cutting-edge approaches (e.g. ancient DNA and faecal related organic compounds) to unequivocally trace the first signs of human activity preserved in long continuous sequences of natural sedimentary archives. Our objective was to perform robust high-resolution climate and environmental reconstructions for the last millennium in order to pinpoint the date that the first settlers arrived, the timing of island occupation and the spread of new settlements. These reconstructions were performed using a multiproxy characterization of sedimentary lacustrine records located on five islands distributed in an NW-SE transect. Preliminary data constrains stratigraphic points that characterize two phases of occupation of Azorean Islands. First human activities started on several islands with the introduction of cattle, extractive forestry and cereal cultivation, followed by extensive deforestation and the large-scale introduction of exotic species on land and into lakes (e.g. exotic plant species and fish introductions), which shaped the present-day lake ecosystems.

Trabajo presentado en la III International Conference on Island Biology, celebrada en La Réunión, del 8 al 13 de julio de 2019, The discovery and colonization of islands are crucial to understand the colonization patterns of new territories, the spread of languages, past economic trade, difiusion of past societal and knowledge during the past millennium. However, historical and archaeological records are scarce and incomplete on many islands, including the Azores, hampering the determination of the exact age of first human settlements. The most commonly accepted date for the first settlement on the Azores islands based on historic documents is 1432 A.D. However, a recent environmental reconstruction of S~ao Miguel island that covers the last 730 years clearly shows that the first-settlements of this island took place by ca. 1287 A.D., approximately 150 years prior to the currently recognized colonization. Here we present a new perspective, using both classical (e.g. pollen and spores from higher plants, fungal spores, algae remains, charcoal particles, plant and animal fragments) as well as cutting-edge approaches (e.g. ancient DNA and faecal related organic compounds) to unequivocally trace the first signs of human activity preserved in long continuous sequences of natural sedimentary archives. Our objective was to perform robust high-resolution climate and environmental reconstructions for the last millennium in order to pinpoint the date that the first settlers arrived, the timing of island occupation and the spread of new settlements. These reconstructions were performed using a multiproxy characterization of sedimentary lacustrine records located on five islands distributed in an NW-SE transect. Preliminary data constrains stratigraphic points that characterize two phases of occupation of Azorean Islands. First human activities started on several islands with the introduction of cattle, extractive forestry and cereal cultivation, followed by extensive deforestation and the large-scale introduction of exotic species on land and into lakes (e.g. exotic plant species and fish introductions), which shaped the present-day lake ecosystems.

III International Conference on Island Evolution, Ecology and Conservation - La Réunion 8-13 July, Previous studies on lacustrine sedimentary sequences in the Azores show that climate variability and vulcanism along with the arrival of humans played a signi#12;cant role in the recent development of these insular Azorean ecosystems. However, the timing and rate of anthropogenic impacts on these lakes is poorly constrained. Paleoecological research allows us to reconstruct ecological conditions prior to and after human settlement, thereby contributing to our understanding of how species and island ecosystems responded to both natural and anthropogenic disturbances. To assess both types of impacts over the last 1000 years, we analysed the elemental geochemistry on bulk organic matter, diatoms, and chironomid remains in a 994 cm-long sediment core recovered from Lake Funda (Flores Island, Azores) in 2017. Preliminary results from Lake Funda show that human colonization was the main driver of ecological changes. We identi#12;ed three major ecological phases: (1) 950-1350 yr AD, a pristine lake ecosystem with mesotrophic diatom taxa, including benthic and tychoplanktonic life-forms, and free-living chironomids species representing an undisturbed environment; 2) 1350-1450 yr AD, the release of cattle and gradual forest clearance lead to an increase in nutrient inputs and the start of the human-impacted phase; and, (3) after Portuguese settlement, from 1450 yr AD to present, a second human-impacted phase resulted in lake eutrophication and the development of an anoxic hypolimnion due to an increase of nutrient loading. The #12;rst anthropogenic phase resulted in a drastic 50% decline of the overall biodiversity with a shift to planktonic diatom species and free-living chironomids, while the second was characterised by a substantial reduction in the density of chironomids and diatom assemblage shifts towards the dominance of Aulacoseira granulata and A. ambigua suggesting a shift in lake trophy. Other external drivers like major climate oscillations likely play a role within these phases as well. Our study demonstrates the sensitivity of aquatic ecosystems in remote islands to anthropogenic impacts that have the ability to overtake natural forces of variability (i.e., climate)., This research is funded by FCT (SFRH/BPD/99461/2014), and through the funded research projects PaleoNAO(CGL2010-15767), RapidNAO (CGL2013-40608-R), PaleoModes (CGL2016-75281-C2), DISCOVERA-ZORES (PTDC/CTA-AMB/28511/2017) and the Luso-American

Goldschmidt 2019 in Barcelona, 18-23 august 2019, The ecological landscape of the Azores, in particular Flores Island, was signifcantly altered by human settlement in the first half of the last millennium, in addition to changes driven by variations in North Atlantic climate and regional volcanic activity. We assessed the environmental impacts of regional climate and human-driven changes in the Azores over the past ~1000 years in a lake sediment record from Lagoa Funda. We tested for changes in the terrestrial landscape and the precipitation regime using compound-specific stable isotopic and chain-length distributions of terrestrial leaf waxes. In addition, we analyzed branched and isoprenoidal glycerol dialkyl glycerol teraethers (brGDGTs and isoGDGTs) to track trophic state changes (in particular eutrophication) after human settlement. The shift in lake sediments from massive to laminated mud in the last 500 to 600 years BP coincides with a significant increase in GDGT-0/crenarchaeol, indicative of increased methanogenic archaeal activity in the water column and the formation of bottom water anoxia. The detection of human activity using fecal sterols allows us to further hypothesize the timing of initial human settlement and the associated environmental impact., This research is funded by the research projects RapidNAO (CGL2013-40608-R), and PaleoModes (CGL2016-75281).