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Pollen analyses of a 90 cm deep lacustrine sediment profile from the Mahasamund District of Chhattisgarh State, central India demonstrated that between ca. 3600 and 2500 cal yr BP (Neoglacial climate interval), open forest vegetation occupied the landscape in the region under a dry climate, probably indicating reduced monsoon (the Indian Summer Monsoon: ISM) rainfall. Further, the open forest vegetation was succeeded by a mixed tropical deciduous forest between ca. 2500 and 1650 cal yr BP (∼550 BC to AD ∼300) under a warm and humid climate with increased monsoon rainfall. The warming period and an amelioration of climate (strong ISM condition) is comparable to the Roman Warm Period (RWP), recorded globally between 2500–1600 cal yr BP (∼550 BC to AD ∼350), and also known as the 'Golden Age of India' owing to increased agricultural output, trade commerce and socio-economic prosperity in India. Subsequently, between ca. 1650 and 950 cal yr BP (AD ∼300–1000), the existing mixed tropical deciduous forest transformed into an open mixed tropical deciduous forest under a warm and relatively less humid climate with reduced monsoon rainfall, correlatable with the Dark Ages Cold Period (DACP). Finally, between ca. 950 cal yr BP to the present (AD 1000 onwards), mixed tropical deciduous forest again came into existence and occupied the landscape around the study area under a warm and relatively more humid climate with intensification of the monsoon rainfall, corresponds with the Medieval Warm Period (MWP), which is known between AD 740 and 1150 worldwide. [ABSTRACT FROM AUTHOR]

Palynological analysis and radiocarbon dating of a short sediment core from a high-altitude mire in the Arasbaran area of northwestern Iran reveals long-term vegetation dynamics, climate change and anthropogenic impact. Our findings indicate the prevalence of semi-desert steppe vegetation, with a variety of Asteraceae – mainly Lactuceae – species from 3000 to 1440 cal yr BP. This period is followed by a higher occurrence of Artemisia spp. and Brassicaceae (1440–1330 cal yr BP), a re-expansion of Lactuceae (1330–1030 cal yr BP) and Brassicaceae (1030–330 cal yr BP) and, finally, Caryophyllaceae species (since 330 cal yr BP). The reconstructed millennia-long dry climate in the highlands of northwestern Iran is in good accordance with climate reconstructions from other east Mediterranean sites. Two phases of moister conditions between 2100–1400 and 1000–350 cal yr BP would correspond to altitudinal Quercus–Carpinus forest expansion in the Arasbaran area. The earliest indication of anthropogenic activity in the area dates back to the onset of the record, around 3000 cal yr BP. The occurrence of small maxima of Juglans regia, Corylus avellana and Cornus mas pollen at around 1350 cal yr BP is interpreted to reflect a temporary expansion of fruit cultivation. For the last millennium the occurrence of pollen attributable to Polygonum, Euphorbia, Plantago and Rumex suggests a diversification of steppe vegetation, which may reflect intensified agropastoral activities in the Arasbaran highlands. Based on our pollen record, the regional vegetation in the Kalan area remained largely stable over the last three millennia. However, changes in local hydrology caused substantial changes in wetland vegetation. [ABSTRACT FROM AUTHOR]

To obtain insight into the natural variability of the coastal ecosystems off southern Kalimantan, late Holocene environmental conditions between ca. 2850 and 990 cal yr BP in the Java Sea were investigated. A 134-cm-long sediment core collected ∼50 km off the Pembuang River mouth was analysed for organic-walled dinoflagellate cysts, pollen/spores and biogeochemical parameters, e.g. organic carbon (Corg), total nitrogen (N) and calcium carbonate (CaCO3) as well as carbon and nitrogen stable isotope composition (δ13C, δ15N). Sediments consist of mixed terrestrial as well as marine organic matter, are characterised by low nutrient uptake and suggest generally low river discharge that is supported by very low pollen and spore concentrations (256 pollen grains cm−3and 20 spores cm−3at maximum, respectively). Foraminifera and coccolithophores dominated the plankton over cyst-producing dinoflagellates and diatoms. Dinoflagellate cyst assemblages are composed mainly of oxidation-resistant species of the generaOperculodiniumandSpiniferiteswith a minor contribution ofImpagidinium(mainlyI. strialatum). The percentages of round brown and peridinioid cysts are low and decrease from the bottom of the core to the top. Palynological and biogeochemical data appear well correlated and synchronously reflect changes in the marine environment. It is reconstructed that after ca. 2480 cal yr BP, bottom waters became increasingly ventilated. A typical open-water dinoflagellate cyst association is gradually replaced by a more coastal association between ca. 2480 and 1530 cal yr BP that is most likely attributed to El Niño-induced seasonal differences between dry and wet periods of the year. After 1530 cal yr BP, a more pronounced influence of the Pembuang River is indicated by an increase in δ15N and decreased δ13C which is supported by the occurrence of nutrient-sensitiveLingulodinium machaerophorumandNematosphaeropsis labyrinthus.The overall results indicate short-scale local environment fluctuations attributed to abiotic factors. [ABSTRACT FROM AUTHOR]

We present the first record ofPotamomycesHyde (Ascomycota, Dothideomycetidae) from soil sediments of the El Palmar National Park, Entre Ríos, Argentina. Nineteen samples were taken (each 2–4 cm from the surface) of a 80 cm thick core composed of a homogeneous lithology of argillaceous fine-grained sands. This taxon was only identified in the basal sample of the core (371 ± 30 years BP), located in a palm area (Butia yatay) with a semi-dense herbaceous-shrub layer. We propose an amendment of the generic diagnosis based on the revision of the species described up to now, and of a new one here defined (P.palmarensis). Additionally, we confirm that the morphotaxonMediaverrunitesJarzen & Elsik ex Nandi & A. Sinha is its junior synonym, so we propose new combinations for seven species. We recommend the use of this natural taxon instead of the morphotaxon in future contributions. In terms of the geographical and stratigraphical distribution ofPotamomyces, our record is the first mentioned for Argentina and the southernmost for South America. Based on its ecological requirements, a humid sub-tropical environment and abundant organic matter in the soil are suggested for the Latest Holocene of the study region. This hypothesis is supported by current knowledge of regional climatic and environmental conditions for the study area during the short humid interval of the Little Ice Age. [ABSTRACT FROM PUBLISHER]