Alessia Masi

The European Modern Pollen Database (EMPD) project

Modern pollen samples provide an invaluable research tool for helping to interpret the quaternary fossil pollen record, allowing investigation of the relationship between pollen as the proxy and the environmental parameters such as vegetation, land-use, and climate that the pollen proxy represents. The European Modern Pollen Database (EMPD) is a new initiative within the European Pollen Database (EPD) to establish a publicly accessible repository of modern (surface sample) pollen data. This new database will complement the EPD, which at present holds only fossil sedimentary pollen data. The EMPD is freely available online to the scientific community and currently has information on almost 5,000 pollen samples from throughout the Euro-Siberian and Mediterranean regions, contributed by over 40 individuals and research groups. Here we describe how the EMPD was constructed, the various tables and their fields, problems and errors, quality controls, and continuing efforts to improve the available data.

Stable isotope analysis of archaeological oak charcoal from eastern Anatolia as a marker of mid-Holocene climate change.

Comparison between modern trees and archaeological charred wood is an under-explored method to study climate change, which may help to infer past environmental changes. The stable carbon content of deciduous oak charcoals was analysed for five periods covering more than a 1000 years (3350-2000 BC) at the site of Arslantepe, Turkey, together with modern deciduous oak specimens from five rare arboreal patches still present in the area (17-64 km from the site). In studies of past climate change it is difficult to distinguish human-induced changes from independent variations, such as the impact of past populations on the landscape and their relationship with climate changes in the mid-Holocene. Archaeology can evaluate climate signals preserved in fossil plants in light of past human life. This paper will contribute to understanding environmental changes that can be attributed to climate variation and those linked to human activities. We compared (13) C/(12) C of modern and fossil oaks in order to correlate the (13) C-content to environmental features of Arslantepe, both today and between 3350 and 2000 BC. At present, this area is semi-arid. The results show important similarities to palaeoenvironmental records for the rest of the Near East. The climate trend can be divided in three main phases: instability phase from ca. 3200 to 2900 BC; a phase of relative stability (until 2350 BC); and a final increase in aridity. The comparison of Δ(13) C values between fossil and modern plants shows that present climate is more arid than that between the end of the fourth and the whole third millennium BC.

Organic geochemical and palynological evidence for Holocene natural and anthropogenic environmental change at Lake Dojran (Macedonia/Greece)

In this study, we present lipid biomarker and palynological data for a sediment core from Lake Dojran (Macedonia/Greece), which covers the entire Holocene period. We analyzed vascular plant-derived n-alkanes, combustion-derived polycyclic aromatic hydrocarbons (PAHs), fecal steroids, and bacterial and archaeal glycerol dialkyl glycerol tetraether (GDGT) lipids in concert with microcharcoal and pollen assemblages to reconstruct climatic, environmental, and human impact in the Dojran catchment and the greater Dojran area. Overall, our results suggest a relationship between anthropogenic activity and environmental/climatic change since increased human impact corresponds to phases of higher humidity and high lake levels at Lake Dojran. During the early Holocene, the record reveals increasing temperatures and humidity and concurrent increasing vegetation cover and runoff/soil erosion, respectively. Following a thermal maximum during the middle early Holocene, temperatures decrease gradually until present. The middle-Holocene at Lake Dojran is characterized by relatively stable environmental conditions followed by greater climatic instability and strong anthropogenic overprint during the late-Holocene. The fecal stanol record reveals phases of increased human impact during the early Bronze Age, the late Bonze/early Iron Age, and the Middle Ages. A phase of low stanol and PAH concentrations from the late Iron Age until the early Middle Ages is either related to ecosystem changes and/or changes in settlement pattern since concurrent pollen data indicate intensified land use. Human impact re-intensified during the Middle Ages with some variability probably related to climatic variations of the ‘Medieval Warm Period’ and the ‘Little Ice Age’.

Climate-driven past fires in central Sicily.

Wildfires in the Mediterranean basin are very important even if their causes and dynamics are not always fully understood. Fire occurrence is driven by several factors, such as the availability of fuel and the amount of biomass. In the Mediterranean basin, the seasonality of climate and its influence on vegetation plays an important role on flammability. Short-term fire dynamics and its relationship with vegetation is the subject of many present-day studies from local to global scales. Long-term fire dynamics can be investigated studying the residues of past plant burnings, such as microcharcoals. Microcharcoals extracted from lacustrine sediments are considered as a fire proxy and pollen as the best one for palaeovegetation reconstruction. We use pollen and microscopic charcoal data from a well-known Holocene sediment record from Lago di Pergusa (Sicily) to analyse their long-term relationships and to gain insights into environmental versus human-induced changes of fire behaviour. At a local scale, the fuel for wildfire is mainly provided by deciduous oaks. On the contrary, irrespective of the regional or local scale of analysis, Mediterranean vegetation seems not particularly fire-prone. Our data show that the largest fires occurred when the precipitation amount in the study area was sufficiently high to allow the development of all vegetation belts, from the Mediterranean to the montane one. Even if no doubt is left on the role of anthropogenic pressure in Sicily in the last few millennia, nonetheless our data highlight the relevant role of climate forcing on wildfires, which is mainly related to regional forest cover and, hence, to biomass and fuel availability.

Archaeobotanical analysis of a Bronze Age well from Sardinia: A wealth of knowledge

In 2008, during a rescue excavation in the Sa Osa area, near the town of Cabras (Sardinia, Italy), a Nuragic settlement was discovered. The excavation revealed numerous pits, wells and structures dug by the local communities between the Early Copper Age and the Iron Age. These structures were interpreted as elements of a settlement mainly involved in primary production. The most remarkable structure is Well-N, radiocarbon and archaeologically dated to the Late Bronze Age, which has yielded large amounts of waterlogged plant remains, animal and fish bones and pottery. Despite the limited set of samples, the combination of macro-remain and pollen analyses in this unique context provides important information useful for exploring not only local subsistence systems but also human impact on the surrounding environment. Grapes and figs are the most abundant remains together with other fruits and edible vascular plants. Remains of melon and mulberry were identified being the earliest remains of these two species for Western Europe. Their presence may confirm early trade between Nuragic people and the eastern Mediterranean and/or African coasts. Intentional selection of wood suggests practices associated to the collection of raw material for specific technological demands. The presence of intestinal parasites in the pollen record points to the possible use of the well as a cesspit, at least in its later use, and this is one of the earliest evidence of this type of structures in prehistoric contexts.

Under the shadow of a big plane tree: Why Platanus orientalis should be considered an archaeophyte in Italy

In Italy, Platanus orientalis L. is judged as an endangered species by some authors and non-native by others: these contrasting assessments can mislead the prioritization of management actions to preserve the species and the riparian vegetation that is its host. Based on a multidisciplinary approach, including palaeobotanical and ecological information, we assessed its status in Italy including the ecological and conservation value of the riparian plant communities hosting it in the Cilento National Park (S-Italy). Palaeobotanical data showed that P. orientalis in Italy should be considered an archaeophyte. According to the ecological assessment of the riparian plant communities hosting P. orientalis, the presence of the species can be interpreted as an indicator of an unfavourable state for the conservation of riparian vegetation. Knowing the status of a species remains one of the first steps to take to correctly propose scientifically based solutions for the conservation of plant diversity. However, there are no absolute criteria for conservation because all conservation objectives can be considered as cultural values. In this context, P. orientalis should be protected as a symbolic tree, an archaeophyte testifying an ancient common Mediterranean cultural heritage, worthy of preservation but outside of natural habitats.

The use of stable carbon isotopes in palaeoenvironmental studies in archaeology: the example of Arslantepe (Malatya, Eastern Anatolia) from 5300 to 3950 years BP

Excavations at Arslantepe have brought to light a lot of archaeobotanical material dating from 5300 to 3950 years BP. The archaeobotanical studies highlighted the presence of various botanical taxa preserved by charring. The great diversity in founding taxa and the selective use of wood can be either due to a choice or selection or even to an environmental availability. Stable carbon isotope analysis was carried out to disentangle the human choice and climate variation. In fact, δ13C values of both fresh and charred wood are environmental proxies and are related to drought stress.Analysis of selected fossil woods (deciduous Quercus and Juniperus sp.) and caryopsis (Triticum dicoccon and Hordeum vulgare) from the archaeological site were carried out. Fresh plant parts (leaf and branches) of the same taxa have been sampled in the Arslantepe area.A lot of studies correlated cultural changes with environmental factors. At Arslantepe a number of important changes are found. It is not clear, however, if the significant variations found in plants use by the successive settlers are due to cultural choices or to environmental changes. Independent information on environmental variation obtained using isotope analysis, will help archaeobotanical studies to discriminate cultural and environmental changes.

Timber exploitation during the 5th–3rd millennia BCE at Arslantepe (Malatya, Turkey): environmental constraints and cultural choices

A considerable amount of charcoal remains from the archaeological site of Arslantepe (Eastern Anatolia) has been analysed. The anthracological assemblage comes from seven archaeological periods, ranging from the Late Chalcolithic 1–2 (mid-5th millennium BCE) to the Early Bronze Age III (late 3rd millennium BCE). The woody taxa exploited by the local communities appeared to have only minor changes throughout the investigated periods. For the evaluation of wood use practices, charcoal was chronologically grouped according to depositional context. The categories of depositional context identified differentiate between the uses of wood for structural parts of buildings, object manufacture, fuel, refuse, and wood found in outdoor areas or in burial contexts. Communities at Arslantepe, characterized by different cultural and socio-economic traits, appeared overall to select timber depending on its use: hydrophilous plants prevail in building material, with the exception of the 2900–2500 BCE period when environmental constraints probably motivate the dominance of woodland-steppe plants. The differential occurrence of taxa in the diverse depositional contexts highlighted cases of under/overestimation of remains, in particular in relation to the woods for construction. Finally, taxa have been attributed to different ecological groups. The interpretation of results and the comparison with other available palaeoenvironmental data point out that climatic factors play only a secondary role in the choice of wood exploitation in the area. Human choice may vary even with constant environmental records.

Regional Vegetation Histories: An Overview of the Pollen Evidence from the Central Mediterranean

Vegetation patterns during the 1st millennium AD in the central Mediterranean, exhibit a great variability, due to the richness of these habitats and the continuous shaping of the environment by human societies. Variations in land use, witnessed in the pollen record, reflect the role that local vegetation and environmental conditions played in the choices made by local societies. The interdisciplinary study of off-site cores remains the key evidence for palaeoenvironmental transformations mirroring the ‘semi-natural’ vegetation, and revealing temporal fluctuations and the amount of human impact on a regional scale.

Erratum to: The European Modern Pollen Database (EMPD) project

Unfortunately, the list of authors contains a number of duplications, omissions and other errors in the original publication of the article. The correct list appears in this erratum.