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Terracing is found widely in the Mediterranean and in other hilly and mountainous regions of the world. Yet while archaeological attention to these ‘mundane’ landscape features has grown, they remain understudied, particularly in Northern Europe. Here, the authors present a multidisciplinary study of terraces in the Breamish Valley, Northumberland. The results date their construction to the Early to Middle Bronze Age, when they were built by cutting back the hillside, stone clearance and wall construction. Environmental evidence points to their use for cereal cultivation. The authors suggest that the construction and use of these terraces formed part of an Early to Middle Bronze Age agricultural intensification, which may have been both demographically and culturally driven.

National audience; Silicon (Si) is the most abundant element on the earth’s surface after oxygen. Si can be found in minerals, electronic chips, cosmetic products, and plants for instance. Here we review the Earth's terrestrial Si cycle, focussing on ecosystem services. We show that silicon can participate in the inherent and manageable properties involved in all ecosystem services. As records of the past, phytoliths can be useful parameters in cultural services. Si is involved in provisioning services because Si may influence the production of food and fibers. Si is also involved in regulating services because of Si involvement in carbon sequestration. Regulating and provisioning services may be improved through Si management, e.g. by application of Si to fertilize soils and plants.

The paper concerns the analysis of the local environment around the multi-layer settlements of Mergen 6 and 7 situated in the immediate vicinity of each other. The settlements existed successively (partly contempora-neously in the early and high Neolithic) in the forest-steppe belt of Western Siberia. Two methods were chosen to obtain the results: spore-and-pollen (palynological) and microbiomorphic analyses of the cultural layers of the settlements of Mergen 6 and Mergen 7. In the settlement of Mergen 6, the following samples were collected for the palynological and microbiomorphic investigation: a vertical column from the center of the ditch of the dwelling no.5; areal soil samples of the dwelling no.5 from underneath the pottery debris of the Neolithic and Eneolithic periods; areal samples from the bottom layer of the dwelling no.21. In the settlement of Mergen 7, two vertical core samples were selected for the pore-and-pollen analysis: in the ditch of the dwelling no.1; and in the inter-dwelling area. Samples from the hearthing of the dwellings and from the inter-dwelling space were collected for the microbiomorphic analysis. The obtained results show that both settlements existed during the forest-steppe conditions, although the original landscapes of the sites chosen by the people for building the settlements were different in the early and high Neolithic. It appears that during the early Neolithic, the settlement of Mergen 6 was associated with an open site with meadow-steppe vegetation; birch forests constituted a small part of the land-scape, whilst there were no pine forests in the close vicinity. During the middle Neolithic, people in the settlement of Mergen 7 preferred to settle in a birch wood, having cleared out a small area to build the dwelling. The results of the microbiomorphic analysis show that, despite the lack of pine forests nearby the settlements, people still used pine tim-ber in housebuilding, apparently, intentionally. The frequent occurrence of remains of the wood detritus at the level of the floor of the dwellings and under pottery supports the initial archaeological observations about timber decking inside the houses. However, pollen and phytolithic studies do not demonstrate a wide use of the wetland waterside vegetation in housebuilding, apparently, because the lake at the time was not overgrown on the banks by reed and cattail. There-fore, despite the close location of the two sites and their similar hunting-fishing specialization of the subsistences, their populations in different chronological periods preferred distinct local conditions.

The primary research goal is to identify differences and diagnostic features of the phytolith spectra of the steppe and forest phytocoenoses. The paper presents the research results of recent soils from various communities. The authors employ the phytolith analysis method. The isolation of phytoliths from recent soils has been carried out with the help of the maceration method and from plants – the dry ashing method. The authors counted the phytoliths using the Olympus BX-51 light microscope. Additionally, the authors have compiled the spectra using the 2C software. The paper compares the phytolith spectra of plain and mountain steppe phytocoenoses. The comparison reveals that the considered plain communities are more similar in phytolith composition than the mountain ones. The following morphotypes are common for all spectra: low conical rondel particles and psilate ribbed particles. These are the forms that characterize steppe communities. Analysis of phytolith spectra of the mountain forest communities demonstrates that the presence of ribbed particles of psilate is common for all spectra. The common feature of all forest spectra is the presence of psilate symmetrical particles, polylobate trapeziforms, lanceolates (trichomes) with a massive base, and trapeziform bilobate (“Stipa-type”) particles. In the spectra of all pine forests, there is a low content or complete absence of needle phytoliths. Diagnostic features of individual phytocoenoses have not been found. The most significant is the ratio of individual phytolith forms in the phytolith spectrum. The comparative analysis of phytolith spectra of the phytocoenoses in the south of western Siberia is carried out for the first time.

Supplementary filesfor 'Investigating the use of grinding tools in prehistoric Bulgaria by phytolith analysis'. ESM 1. Full description of the protocol used to process archaeological samples for phytolith extraction and other files relevant to the methods. ESM 2. Phytolith datasets, including the full counting sheet, the processing weights and the dataset used for multivariate statistics. ESM 3. Description of the methods and the results of the XRF analysis of two grinding tools.

The Beganchik locality is a stratigraphic sequence of loessic deposits, pedogenic horizons and Paleolithic occupations located at the Kama-Volga confluence. The sequence is exposed on a bluff formed on the west side of an erosional remnant between the Kuybyshev Reservoir and the former channel of the Aktay River. Although the site is known for its Terminal Paleolithic-Mesolithic occupations of the Pleistocene-Holocene transition, evidence of older occupations and remains of fauna has been identified. Our research team identified evidence of human presence associated with a pedogenic horizon of MIS 3 age. Two AMS radiocarbon ages from a hearth produced ages around 47 000 years BP. Pollen and phytoliths from two soils horizons, including the one associated with the hearths indicate a steppe environment coincident with the formation of correlative soils elsewhere in the Russian Plain.

Silicon (Si) accumulation is known to alleviate various biotic and abiotic stressors in plants with potential ecological consequences. However, for dicotyledonous plants our understanding of Si variation remains limited. We conducted a comparative experimental study to investigate (1) interspecific variation of foliar Si concentrations across 37 dicotyledonous forbs of temperate grasslands, (2) intraspecific variation in foliar Si concentration in response to soil Si availability, the influence of (3) phylogenetic relatedness, and (4) habitat association to moisture. Foliar Si differed markedly (approx. 70-fold) across the investigated forbs, with some species exhibiting Si accumulation similar to grasses. Foliar Si increased with soil Si availability, but the response varied across species: species with higher Si accumulation capacity showed a stronger response, indicating that they did not actively upregulate Si uptake under low soil Si availability. Foliar Si showed a pronounced phylogenetic signal, i.e., closely related species exhibited more similar foliar Si concentrations than distantly related species. Significant differences in foliar Si concentration within closely related species pairs nevertheless support that active Si uptake and associated high Si concentrations has evolved multiple times in forbs. Foliar Si was not higher in species associated with drier habitats, implying that in dicotyledonous forbs of temperate grasslands high foliar Si is not an adaptive trait to withstand drought. Our results demonstrated considerable inter- and intraspecific variation in foliar Si concentration in temperate forbs. This variation should have pervasive, but so far understudied, ecological consequences for community composition and functioning of temperate grasslands under land-use and climate change. Supplementary Information The online version contains supplementary material available at 10.1007/s00442-021-04978-9.

Phytolith analysis is a well-established archaeobotanical tool, having provided important insights into pre-Columbian crop cultivation and domestication across Amazonia through the Holocene. Yet, its use as a palaeoecological tool is in its infancy in Amazonia and its effectiveness for reconstructing pre-Columbian land-use beyond archaeological sites (i.e., ‘off-site’) has so far received little critical attention. This paper examines both new and previously published soil phytolith data from SW Amazonia to assess the robustness of this proxy for reconstructing pre-Columbian land-use. We conducted the study via off-site soil pits radiating 7.5 km beyond a geoglyph in Acre state, Brazil, and 50 km beyond a ring-ditch in northern Bolivia, spanning the expected gradients in historical land-use intensity. We found that the spatio-temporal patterns in palm phytolith data across our soil-pit transects support the hypothesis that pre-Columbian peoples enriched their forests with palms over several millennia, although phytoliths are limited in their ability to capture small-scale crop cultivation and deforestation. Despite these drawbacks, we conclude that off-site soil phytolith analysis can provide novel insights into pre-Columbian land use, provided it is effectively integrated with other land-use (e.g., charcoal) and archaeological data.

Phytoliths are intra and extracellular siliceous deposits present in different plant tissues. Si uptake and transport are mediated by Lsi genes and its concentration is associated with forage quality. Our objective was to determine the phytolith content in seven Eragrostis curvula genotypes at the outbreak and re-growth stages to assess its relationship with the forage quality parameters and perform a genome-wide analysis to detect the presence/absence of Lsi genes. The mean values of the phytolith content of dry matter varied between 1.94–2.26% and 2.72–4.71% at the outbreak and re-growth stages, respectively, with highly significant differences among the genotypes and phenological stages. A highly negative correlation was observed in the phytolith content and in vitro dry matter digestibility and crude protein, revealing its importance as a selection parameter in breeding programs. A positive correlation was obtained between the phytolith content and lignin, neutral detergent fiber, and acid detergent fiber. The main morphotypes of the phytoliths included saddle-shaped, bulliform, and acicular cells. Genes Lsi1, Lsi2, Lsi3, and Lsi6, previously reported in silica uptake, were identified and compared with related species, being the gene sequences highly conserved, meaning that its accumulation is probably due to differences in the gene expression or different allelic variants among cultivars.

Drought is an abiotic stress that may be aggravated by climate changes with increasingly warmer and drier summers. This is a severe problem in the chestnut crop in Portugal due to its need for water during this time, which is essential for good formation and development of the fruit. Si fertilization is referenced by several authors as important in the tolerance of plants under drought. The experiments were carried out in the field trial and chestnuts were fertilized with 0, 5, 7.5, and 10 mM potassium silicate (SiK), which was applied to the soil and to the leaves and exposed to a non-irrigation and an irrigation phase during the summer. Results indicate that Si fertilization increased the relative water content and water potential, while the transpiration rate, stomatal conductance, and stomatal density were reduced under deficit irrigation in Si-treated plants (10 mM SiK). Moreover, the Si induces a higher photosynthetic activity and vessel frequency with a smaller diameter, promoting a higher relative hydraulic conductivity and a lower vulnerability to cavitation. This work suggests that Si can be used as a potential source to induce drought tolerance in chestnuts.

Widespread ethnographic evidence exists for the addition of animal dung to clay during the process of ceramic production. However, conclusive evidence of dung tempering in archaeological ceramics is relatively rare. The aim of this study is to ascertain whether, and under which conditions, dung tempering of pottery is identifiable. To answer these questions, we assessed whether a combination of micro-particle analysis in loose sediment and thin-section petrography can reveal the addition of dung to the clay paste by focusing on faecal spherulites, ash pseudomorphs, phytoliths and coprophilous fungal spores. We analysed several series of experimentally produced ceramic briquettes tempered with different types of dung and dung ash, which were fired at a range of increasing temperatures. Our study shows that the identification of dung tempering represents a challenge, and it depends on a number of different factors, among others the original presence of dung markers in the dung used, the manufacturing process, the firing temperatures and the firing atmosphere. Overall, through a multidisciplinary approach, our work clarifies a variety of issues connected to the identification of dung in ancient pottery, highlighting the role of faecal spherulites as the most promising proxy. This work was supported by the Excellence Initiative of the Eberhard Karls Universität Tübingen and the Ministry for Science, Research, and Art of Baden-Württemberg. SGA’s work has been funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie H2020-MSCA-IF-2017, grant agreement number 794823, MapDung project.

This study examines the contribution of ethnoarchaeological and experimental research to interdisciplinary approaches on the identification and taphonomy of livestock dung. Ethnographic and experimental records provide comparative reference models on a range of taphonomic issues that are still understudied, such as variation in the type and preservation of plant and faecal microfossils that are excreted with dung and the effects of heating. The focus in the present study is on the taphonomy of ingested phytoliths and calcitic spherulites that originate in the digestive tracts of cattle, sheep and goat found in fresh modern dung pellets. The reported records are from the modern farming village of Bestansur, Iraqi Kurdistan. The experimental results show significant changes in microfossil composition and phytolith and spherulite stability and integrity, with increased melting of phytoliths and variations in morphotype composition (e.g. grass short cells appear less stable) from heating at temperatures around 800°C, whereas the spherulite darkening occurs within a range between 500–700°C, with a maximum production at 650°C. This integrated approach illustrates the contribution of the much-needed ethnographic and experimental records of animal dung to understanding of taphonomic issues, which are fundamental for the interpretation of this valuable microfossil material in archaeology., This research was conducted within the framework of the MICROARCHEODUNG and the Central Zagros Archaeological Project (CZAP). The first author’s work has been funded by the European Union’s MICROARCHEODUNG project. The project has received funding from the EU Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No H2020-MSCA-IF-2015-702529. GA’s work has been supported by an University of Reading Undergraduate Research Opportunities Programme fellowship supervised by MP and WM. KD’s research was supported by an AHRC South West and Wales Doctoral Training Partnership PhD studentship and placement.

Mwanganda's Village (MGD) and Bruce (BRU) are two open-air site complexes in northern Malawi with deposits dating to between 15 and 58 thousand years ago (ka) and containing Middle Stone Age (MSA) lithic assemblages. The sites have been known since 1966 and 1965, respectively, but lacked chronometric and site formation data necessary for their interpretation. The area hosts a rich stone artifact record, eroding from and found within alluvial fan deposits exhibiting poor preservation of organic materials. Although this generally limits opportunities for site-based environmental reconstructions, MGD and BRU are located at the distal margins of the alluvial fan, where lacustrine lagoonal deposits were overprinted by a calcrete paleosol. This has created locally improved organic preservation and allowed us to obtain ecological data from pollen, phytoliths, and pedogenic carbonates, producing a regional-to site-scale environmental context for periods of site use and abandonment. Here, we integrate the ecological data into a detailed site formation history, based on field observations and micromorphology, supplemented by cathodoluminescence microscopy and mu-XRF. By comparing local, on-site environmental proxies with more regional indicators, we can better evaluate how MSA hunter-gatherers made decisions about the use of resources across the landscape. Our data indicate that while tree cover similar to modern miombo woodland and evergreen gallery forest prevailed at most times, MSA hunter-gatherers chose more locally open environments for activities that resulted in a lithic artifact record at multiple locations between 51 and 15 ka.(C) 2022 The Authors. Published by Elsevier Ltd. info:eu-repo/semantics/publishedVersion

Fumier sequences play a primary role in the study of livestock management and the use of space in prehistoric pastoralist societies. These sequences are formed when dung accumulated in sheepfold caves and rock shelters is burnt, resulting in an overlapping of burnt and unburnt sedimentary layers. Thus, fire is a key taphonomic agent in the formation and alteration of fumier sequences.The characteristics, functions, and management of burning events influence the preservation of the macro- and micro-remains potentially biasing the interpretation of the archeological record. Therefore, it is important to understand the taphonomic effects of fire in fumier sequences.In this chapter, we use a multi-scalar and interdisciplinary approach to the study of burning events at El Mirador cave. We analyzed the phytolith, fecal spherulites, pollen, non-pollen palynomorphs (NPP), and parasite remains in the fumier sequence, together with the mineral (FTIR) and magnetic properties of the sediments. In addition, we studied the effects of fire on the macrofaunal assemblages. The results obtained here provide the basis for a tapho-diagenetic framework that illustrates robustly the formation dynamics of the El Mirador fumier sequences.

The primary research goal is to identify differences and diagnostic features of the phytolith spectra of the steppe and forest phytocoenoses. The paper presents the research results of recent soils from various communities. The authors employ the phytolith analysis method. The isolation of phytoliths from recent soils has been carried out with the help of the maceration method and from plants – the dry ashing method. The authors counted the phytoliths using the Olympus BX-51 light microscope. Additionally, the authors have compiled the spectra using the 2C software. The paper compares the phytolith spectra of plain and mountain steppe phytocoenoses. The comparison reveals that the considered plain communities are more similar in phytolith composition than the mountain ones. The following morphotypes are common for all spectra: low conical rondel particles and psilate ribbed particles. These are the forms that characterize steppe communities. Analysis of phytolith spectra of the mountain forest communities demonstrates that the presence of ribbed particles of psilate is common for all spectra. The common feature of all forest spectra is the presence of psilate symmetrical particles, polylobate trapeziforms, lanceolates (trichomes) with a massive base, and trapeziform bilobate (“Stipa-type”) particles. In the spectra of all pine forests, there is a low content or complete absence of needle phytoliths. Diagnostic features of individual phytocoenoses have not been found. The most significant is the ratio of individual phytolith forms in the phytolith spectrum. The comparative analysis of phytolith spectra of the phytocoenoses in the south of western Siberia is carried out for the first time.

This paper presents the results of a study on fluctuations in the water level of the Curonian Lagoon (in the Baltic Sea). To date, the genesis of this inland bay as part of the complex postglacial development of the southeastern Baltic is poorly understood. The data from lithological, geochronological, and phytolith analyses, as well as assessments of plant and animal macroremains from the lagoonal sediments, provide a reconstruction of local coastal biocenoses and water level dynamics in the Middle and Late Holocene time. This study reveals the fairly dynamic evolution of the coastal zone of the Curonian Lagoon over the past 7000 years, as indicated by the traced succession of plant communities from forest to near-shore, open-water biocenoses and the alternations of the drying out and inundation of the area under consideration. Thus far, a connection with two stages of the Baltic Sea water level fluctuations has been traced: the regressional stage, which took place approximately 5600 cal years BP, and the Late Subatlantic transgression, which started at approximately 1100 cal BP. This study demonstrates that phytolith (microbiomorphic) analysis is a promising method for the study of temperate-latitude lagoonal sediments, providing information not only on the local plant communities, but also on the changes in the hydrological regime of the area.

Dental microwear analysis is a proxy for analysing the diet in extinct and extant vertebrates, especially mammals. The limits of these approaches are still rather poorly known, especially in terms of taphonomic impacts. Indeed, several physical or chemical phenomena may have altered the microscopic features linked to the diet and compromised their study. In this article, we evaluate the effect of sediment abrasion on teeth on low-magnification tooth wear studies. We used a tumbling machine in order to reproduce abrasion marks on 57 molars and premolars of Equus sp., Capra hircus and Sus scrofa employing two types of sediments: a mixture of clay and sand sediment with small (150–200 μm) and rounded particles and a sandy one with larger (350–500 μm) and sub-angular particles. The teeth underwent up to 2 h of tumbling simulation, and casts were made at regular intervals in order to evaluate the evolution of the taphonomic impact over time. Our experiment shows that both sediments strongly alter the teeth after a certain time; the fine particles contained in the mix of sand and clay sediment have a much stronger impact on the enamel than the sand; the mix of clay and sand sediment tends to increase the number of pits and reduce the number of scratches, vice versa for the sand; and sedimentary and dietary marks do not have the same morphology and can be distinguished. The abrasion marks (compared to dietary scratches) tend to be wider, shorter, with an isotropic distribution, more frequent on the most exposed parts of the teeth (such as the cusps or the edges). The pits resulting from sediment tumbling present an irregular morphology in comparison with dietary pits, which are rounder. Both sediments have an impact on the enamel surfaces. Thus, when signs of taphonomic alteration (e.g. presence of abrasion marks, taphonomic pits, notches in the edges of enamel) are documented, we recommend avoiding studying the tips of the cups of the Suidae (and probably other bunodont teeth) and the portions of enamel at the edge of equid teeth which are more affected by taphonomic processes, especially in the mix of sand and clay sediment. This work has important implications for microwear studies applied to fossil samples. It makes it possible to recognize some taphonomic features linked to mechanical abrasion of the enamel, to consider with more caution the teeth that have been preserved in fine sediment and to choose, in order to characterise the diet, the areas least impacted by taphonomic alterations., This research was funded by the International Research Network (IRN 0871 CNRS-INEE): Taphonomy European Network (TaphEN). It has also been supported by LabEx ARCHIMEDE from the “Investissement d’Avenir” programme ANR-11-LABX-0032–01. The research of FR is supported by the Spanish Ministry of Science and Innovation through the PID2019-103987 GB-C31project and the “María de Maeztu” excellence accreditation (CEX2019-000945-M) and by the Generalitat de Catalunya through the 2017 SGR 836 project and the CERCA Program/Generalitat de Catalunya. A. X. was funded by the Austrian Science Fund (FWF, project number P29501-B25). A. P. is supported by the Spanish Ministry of Science and Innovation (FJC2019-040804-I, Subprograma Juan de la Cierva-Formación).

Orientador: Francisco Sérgio Bernardes Ladeira Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências Resumo: As planícies fluviais são feições deposicionais do vale de um canal associadas a um regime climático ou hidrológico particular da bacia de drenagem, nesse sentido, os sedimentos são temporariamente armazenados e processos de agradação ou degradação serão responsáveis pela dinâmica nestes compartimentos. Em função dessa dinâmica, sobretudo no clima tropical úmido, os depósitos fluviais são rapidamente alterados quimicamente e horizontes pedológicos poderão evoluir, reunindo ali uma série de nutrientes e elementos químicos responsáveis pela ocupação de uma vegetação típica, em às condições climáticas, sedimentares, hidrológicas e pedológicas regionais. Nessas unidades geomorfológicas ocorre uma alta diversidade de habitats terrestres, transicionais e aquáticos em diferentes estágios de evolução, o sistema rio-planície fluvial traz um alto grau de heterogeneidade de processos físicos, químicos e bióticos, portanto, tais áreas possuem enorme potencial ecológico e preservam importantes informações ambientais do passado. O objetivo deste trabalho foi interpretar tais informações no que toca a evolução da bacia do Rio Pardo, desde a sua nascente no estado de Minas Gerais até a sua foz junto ao Rio Grande, na divisa entre São Paulo e o triângulo mineiro. Preliminarmente, algumas características morfométricas foram levantadas com o objetivo de identificar indícios de ajustamentos recentes na bacia que tenham influenciado a dinâmica do canal, analisando espacialmente a distribuição de anomalias de drenagem, perfis longitudinais, lineamentos estruturais e falhas. De posse dessas informações partiu-se para a análise de 14 perfis de solo selecionados ao longo da planície fluvial do Rio Pardo e afluentes, onde 7 foram estudados quanto às suas características químicas, granulométricas e micromorfológicas, associando-as aos ambientes de sedimentação e aos principais processos de intemperismo, incluindo datações por 14C e Luminescência Ópticamente Estimulada (LOE). Os resultados mostraram que os processos de intemperismo são bastante significativos mesmo em ambientes onde a pedogênese pode ser ocasionalmente interrompida por depósitos fluviais. As análises mostraram que muitos destes processos de alteração estão ainda em curso, na micromorfologia observou-se em alguns perfis zonas de alteração de Biotitas/Muscovitas para argilominerais. Na macromorfologia observou-se que em determinadas situações a pedogênese foi capaz inclusive de gerar horizontes Bt, pouco comuns em áreas de drenagem pouco eficiente, como são as planícies fluviais, por esse motivo foi essencial a utilização da metodologia de fácies sedimentares, pois através dela foi possível identificar através da arquitetura do depósito qual a sua posição relativa dentro da planície, que poderia favorecer ou não os processos de alteração química. Observou-se também que há registros de climas mais frios e secos na bacia no período entre 35.000 e 17.000 anos, que se mantiveram até o último máximo glacial (? 17.000 AP). No Holoceno Médio (6000 a 3845 anos A.P) o clima passou a um estágio mais quente e úmido que o atual, com predomínio das gramíneas, mas com aumento de fitólitos de Palmeiras, assim como empobrecimento isotópico de 13C. No Holoceno Superior o clima passou a ser tipicamente quente e úmido, com maior participação de morfotipos de árvore e arbustos e também das Palmeiras, indicando uma vegetação mais próxima aos cerrados que hoje ocupam a porção mais à jusante da bacia Abstract: Floodplains are depositional features of a channel valley conected to a specific climatic or hidrologic condition of the drainage basin, in this sense, sediments are temporarily stored and agradation or degradation processes will be responsible for the dynamics of these units. As a function of this dynamics, mostly in humid tropics, floodplain deposits are fastly chemically weathered and soil horizons could evolve, yielding nutrients and chemicall elements responsible for the ocupation of a typical vegetation, as an answer of climatic, sedimentary, hidrologic and pedologic conditions. These geomorphologic units have a high diversity of terrestrial, transitional and aquatic habitats in different stages of evolution, the river-floodplain system brings high degree heterogeneity of physical, chemical and biotic processes, therefore, such areas have an important ecological potential and are able to preserve data from past environments. The aim of this work was to understand such informations about the evolution of Pardo River basin, from its headwaters in Minas Gerais state to the mouth, at Grande River, at the borders of São Paulo state and "triângulo mineiro". Preliminarily, some morphometric features were carried out in order to identify evidences of recent adjustments in the basins that changed channel dynamics, particularly the drainage anomalies distribution, longitudinal profiles, structural lineaments and faults. Regarding these basic informations, 14 soil profiles were selected in the floodplains of Pardo river and their affluents, where 7 were studied regarding chemical, grain size and micromorphology features, associating them to the architecture of sedimentation and to weathering processes, including 14C and OSL (Optically stimulated luminescence) datings. The results showed that weathering processes are very significant even tough in situations where pedogenesis could be ocasionaly interrupted by floodplain deposits. Most of these processes are still running, micromorphology analysis has revealed transformation of Biotite/Muscovite into clay minerals in several profiles. Macromorphology has revealed that in some situations the soil forming processes were able to generate Bt horizons, unusual in poorly drained areas such as floodplains, for that reason the sedimentary facies method used was essential, only by using it we could identify the deposit architecture and its relative position on floodplain, which could support or not chemical weathering processes. Records of climates colder and drier than today were identified between 35000 and 17000 years BP, situation kept until the last glacial maximum (? 17000 BP). In the Middle Holocene (6000 a 3845 years BP) climate changed to a warmer and wetter than today condition, where grass phytoliths prevailed despite an increase of palms as well as an impoverishment of 13C signal. In Upper Holocene the climate changed to a typical warm and humid tropical condition, with higher participation of trees, schrubs and palms phytoliths, which indicated a vegetation closer to the savannas that are spread today mostly on upper parts of the basin Doutorado Análise Ambiental e Dinâmica Territorial Doutor em Geografia FAPESP 2011/00261-3

The Saltgrasses are pioneer plants in the early stages of succession in saline soils and constitute particular zonal communities of low species variability. Phytolith assemblage analysis of these species allows a community type to be characterized that consists mainly of species with well-defined environmental adaptations, which are significant because of their paleoecological importance. The aim of the present study is to characterize phytolith assemblages of Distichlis species in South America, emphasizing their leaf morphotypes. Four Distichlis species, mainly of South American distribution, and four chloridoids species from different clades of the subfamily (Lycurus, Eragrostis, Muhlenbergia and Sporobolus) were selected for this study. The phytoliths were obtained following Labouriau's calcination technique. Quantitative analysis of the morphotype abundance in the phytolith assemblages studied allowed the three main groups to be distinguished, with the common presence of multicellular phytoliths with long, short, bulliform and subepidermal silicified cells, as well as unicellular phytoliths, such as short narrow saddle, prickles and hairs, polyhedral and long elongate types. Conversely, the exclusive presence of horned towers, short truncated cones, circular/ovoid, papillae trichome, silicified microhairs, and isolated and articulated irregular epidermal cell phytoliths in Monanthochloinae clade species distinguishes them from the Muhlenbergiinae clade species with square/rectangular and subrectangular saddles and acute dumbbells. Eragrostis and Sporobolus species have shown some particular morphotypes (such as hairs with cushions, long truncate cones, dumbbell and dumbbell/saddle). The results not only allowed us to identify the Distichlis species, but also to distinguish them from other grasses, including those in their subfamily; and represent a potential tool to identified halophytes environments outside New World saltgrasses. Fil: Zucol, Alejandro Fabián. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina Fil: Patterer, Noelia Isabel. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina Fil: Moya, Eliana Vanesa. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina Fil: Fernández Pepi, María Gabriela. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Although palms are recognized as a plant group of tropical and sub-tropical ecosystems, in South America they can also be found in temperate savannas under certain conditions. Therefore, since these plants have been widely used as palaeoindicators in warm and humid climates, it is important to know what phytolith contribution these plants have made in temperate environments. El Palmar National Park (Argentina) protects the largest remnant of savanna palm, Butia yatay (Mart.) Becc., one of the southernmost palm communities in the continent. This modern analogue study assessed the variability of silica phytoliths in 15 selected species of plants, 20 mulch samples (organic horizon) and 60 soil samples that were collected in all the plant communities selected for this study: dense palm trees (DPT), shrubbery with isolated tall palms (SIP), psammophile steppe (PS) and humid psammophile steppe (HPS). Our results show that grasses exhibit the most diverse forms. Palms, sedges and dicots can be distinguished by the different proportions of several diagnostic morphotypes. Palm tree communities can be characterized based on a presence a high proportion of globular echinate and trapeziform sinuate/oblong phytoliths. Psammophile steppes have a high proportion of bilobate, polylobate and cross phytoliths and a low presence of globular echinate. Humid psammophile steppes show a high presence of bilobate, cross and dicot phytoliths with a low proportion of trapeziform sinuate/oblong phytoliths and an absence of globular echinate morphotypes. The ratio of palm to grass phytoliths allowed us to obtain differences between the palm groves, psammophile steppe and humid psammophile steppe ecosystems. These analyses can then be used to determine this type of ecosystem in temperate humid savannas. Phytolith assemblages provide an important record for the characterization of the plant-soil system and production-incorporation system in mixed communities as a tool in the construction of palm trees paleoenvironments. Fil: Patterer, Noelia Isabel. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina. Universidad Autónoma de Entre Ríos; Argentina Fil: Zucol, Alejandro Fabián. Universidad Autónoma de Entre Ríos; Argentina. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina Fil: Fernández Pepi, María Gabriela. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Brea, Mariana. Universidad Autónoma de Entre Ríos; Argentina. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina

International audience; A recent publication on the phytolith assemblage at Fahien rockshelter, Sri Lanka (Premathilake and Hunt) is argued to represent: the exploitation of wild Musa acuminata and M. balbisiana during the Late Pleistocene; the introduction of edible diploid cultivars from the Southeast Asia-New Guinea region during the early to mid-Holocene; the generation and cultivation of triploid banana hybrids on Sri Lanka before 6194-5994 cal bp; and the subsequent spread of derived triploid cultivars to mainland India and westward to Africa. A careful review of the archaeobotanical research presented by Premathilake and Hunt, in the context of broader multidisciplinary evidence (agronomy, archaeobotany, genetics and linguistics) for the domestication and spread of banana cultivars, indicates that three main aspects of their argument are problematic: the lack of clarity in the characterization of banana domestication in the past; the methods used to discriminate phytoliths into banana taxa; and the promotion of Sri Lanka as a source region rather than a recipient of banana cultivars. Following reconsideration, the Fahien evidence is consistent with previous interpretations for the origins of diploid and significant triploid cultivars outside of Sri Lanka and dispersal to that island.

Domestic rice agriculture had spread across the mainland Indian subcontinent by c.500 BC. The initial spread of rice outside the core zone of the central Gangetic Plains is thought to have been limited by climatic constraints, particularly seasonal rainfall levels, and so the later spread of rice into the dry regions of South India is largely supposed to have relied on irrigation. This has been associated with the development of ritual water features in the Iron Age (c.1000–500 BC), and to the subsequent development of tanks (reservoirs) during the period of Early Historic state development (c.500 BC–500 AD). The identification of early irrigation systems within South Asia has largely relied on early historical texts, and not on direct archaeological evidence. This initial investigation attempts to identify irrigated rice cultivation in the Indian subcontinent by directly examining rice crop remains (phytolith and macrobotanical data) from four sites. The evidence presented here shows that, contrary to accepted narratives, rice agriculture in the Iron Age-Early Historic South India may not have been supported by irrigated paddy fields, but may have relied on seasonal rainfall as elsewhere in the subcontinent. More caution is urged, therefore, when using terms related to ‘irrigation’ and ‘agricultural intensification’ in discussions of the Iron Age and Early Historic South Asia and the related developments of urbanism and state polities. Electronic supplementary material The online version of this article (10.1007/s12520-019-00795-7) contains supplementary material, which is available to authorized users.

Among the buried urban Anthrosols and Technosols, urban Dark Earth composes a major challenge to urban archaeologists and soil scientists. These homogeneous units are often the result of a complex formation history, involving human actions and natural processes. In order to understand the significance of the late medieval to pre-industrial urban Dark Earth observed on the site of Mundaneum in the historical centre of Mons (Belgium) an integrated soil micromorphological and phytolith study has been performed. The aim of this study is to understand how the urban Dark Earth formed and to identify the major natural and human processes that are involved in its formation. The results show that major natural processes are bio- turbation, sedimentation, humification, alkalinisation and clay translocation. These processes are mainly human induced. Main human activities include cereal cultivation, horticulture, dumping of waste and trampling. Phy- toliths proved to be an important witness of the presence of plant material, in a context where organic remains tend to decompose rapidly. The integrated approach allowed to come to a better understanding of the tapho- nomical history of the phytoliths, hence permitting to distinguish plant remains related to manure, cereal pro- cessing and in situ cultivated plants. The study further permitted the authors to gain insight in part of the biography of the site and its surroundings, hence showing changes in spatial organisation and the progressive urbanisation of the area. As such, this analysis provides an important stepstone to the further geoarchaeological study of town development in Medieval and Modern periods.

International audience; At Gien (France), indoor floors from early Middle Ages occupation (8th–10th c. AD) are very well preserved, providing a new reference for archaeological investigation in northern France. This site is located on an outcrop, 20 m above the Loire valley, where a 15th c. castle stands now. The medieval occupation combines high-status houses with crafting and agricultural areas. They constitute a new urban nucleus, which grew 2 km east from an ancient Roman settlement. During the rescue excavation, four buildings of different status were sampled and studied using an integrated approach, combining stratigraphy, micromorphology, chemical, macro-remain and phytolith analyses. Micromorphological investigations helped to identify 74 built floors, from 0.5 to 150 mm thick, made with transformed local clay or imported silty earth. Mineral floors were covered by vegetal ones, consisting of crop processing refuse. These litters include an abundance of phytoliths and some seeds, both produced by cultivated cereals, which were processed in situ, such as Triticum durum, Secale cereale and Hordeum vulgare. The refuse above the mineral and vegetal floors were trampled. They were produced not only by domestic activities, such as cooking and eating, but also by metallurgic activities and animal husbandry. The investigation of a contemporary pit indicated that, despite the large amount of refuse, floors were well maintained and regularly rebuilt. The spatial distribution of waste indicated that a single space could be dedicated to several activities, which were not necessarily separated by new floors. Moreover, the total absence of bioturbation allowed the study of a stage of dark earth formation, by comparing it to the contemporaneous mechanical disturbance of a part of the strata which occurred when building new floors. All these results give new evidence of the richness and the complexity of the early Middle Ages town, in addition to help identifying the activities which could take place in early castral areas.

Le pays bassar, localisé au Nord du Togo, fait partie des plus importants centres sidérurgiques pré-colonial en Afrique de l’Ouest. S’il est attesté que la métallurgie du fer, qui débuta au début de notre ère, représente un tournant dans l’histoire des Sociétés, l’impact de cette activité sur l’environnement, qu’il soit direct (besoin en combustible) ou indirect (développement de l’agriculture grâce aux outils agricoles) a été très peu étudié. L’étude géomorphologique et phytolithique des archives sédimentaires de cinq tronçons localisés dans la haute et moyenne vallée du Tatré, petit cours d’eau du pays bassar a été réalisée. Cette démarche multiproxy et multiscalaire permet d’affiner l’échelle spatiale (locale, extra-locale) et temporelle (continue, brutale) des dynamiques paléoenvironnementales mais aussi de mesurer l’impact de la métallurgie sur les milieux. Elle offre ainsi l’opportunité de reconstruire l’histoire d’un système fluvial soudano-guinéen durant les deux derniers millénaires en essayant de faire la part du rôle joué par les forçages climatiques et/ou anthropiques. Les quatre phases hydro-sédimentaires identifiées révèlent des réponses variées. Les deux premières phases (avant le XVe siècle) témoignent de réponses synchrones du système fluvial à des forçages climatiques externes. En revanche, le modèle de la troisième phase (XVe - XXe siècle) qui s’illustre par une incision puis par un détritisme d’origine colluvio-alluviale très marqués, atteste d’un déséquilibre hydro-sédimentaire localisé à l’amont. Datant de la période d’activité métallurgique la plus intense, de nombreuses scories ont été identifiées dans ces dépôts. La dernière phase très récente (XXe siècle) est le résultat d’une combinaison de facteurs locaux et régionaux. The Bassar area, located in North Togo, is one of the most important pre-colonial West African metallurgical centres. The onset is considered to date back to the beginning of our era and metallurgy continued as late as the early 20th century. Despite the fact that iron metallurgy represents a turning point in the history of Societies, the impact of this activity on the environment, whether direct (need for fuel) or indirect (development of agriculture through iron tools) is not sufficiently understood. The geomorphological and phytolithical studies of the sedimentary filling from five reaches located in the upper and middle Tatré valley, a small river of the Bassar area, have been conducted. This multiproxy and multiscale approach allows to define the spatial scale (local/extralocal) and the time scale (continuous/abrupt) of the palaeoenvironmental dynamics more precisely and also to detect the impact of the past iron production on landscapes. It provides the opportunity to reconstruct the Sudano-Guinean fluvial system dynamics during the last two millenia and to identify the role played by climatic and/or anthropogenic triggers. Four distinct sediment distribution patterns have been highlighted. The two first periods (before 15th century) testify to synchronous responses of the fluvial system to external climatic triggers. The third pattern (15th - 20th centuries), dating from the most intense iron production period, represented by a strong incision and then by a coarse colluvio-alluvial filling suggests a local hydro-sedimentary instability. The last recent phase (20th century) highlights the combined role played by local and regional factors.

Archaeobotanical evidence from two Early Historic sites in Sri Lanka, Kantharodai and Kirinda, is reported, providing significant evidence for agricultural diversity beyond the cultivation of rice. These data highlight the potential of systematic archaeobotanical sampling for macro-remains in tropical environments to contribute to the understanding of subsistence history in the tropics. Direct AMS radiocarbon dating confirms both the antiquity of crops and refines site chronologies. Both sites have Oryza sativa subsp. indica rice and evidence of rice crop-processing and millet farming. In addition, phytolith data provide complementary evidence on the nature of early rice cultivation in Sri Lanka. Both Kantharodai and Kirinda possess rice agriculture and a diverse range of cultivated millets (Brachiaria ramosa, Echinochloa frumentacea, Panicum sumatrense, and Setaria verticillata). Pulses of Indian origin were also cultivated, especially Vigna radiata and Macrotyloma uniflorum. Cotton (Gossypium sp.) cultivation is evident from Kirinda. Both sites, but in particular Kirinda, provide evidence for use of the seeds of Alpinia sp., in the cardamom/ginger family (Zingiberaceae), a plausible wild spice, while coconuts (Cocos nucifera) were also found at Kirinda.

V pozdně neolitickém nalezišti Ustie na Drim, v severní části jezera Ohrid (Severní Makedonie), v odkrytém v roce 1962, se nalezly keramické fragmenty velkých plochých podlouhlých pánví. Tyto artefakty by mohly být datovány relativní chronologií zhruba do doby kolem 5200–5000 před naším letopočtem. Keramické pánve byly podle tvaru a technologických vlastností pravděpodobně používány k pečení. Přichycené materiály na povrchu studovaných fragmentů pánve byly odebrány pro následné chemické a mikroskopické analýzy (tj. analýzy škrobu, fytolitů a mikroskopických zvířecích pozůstatků). Imunologická metoda odhalila ve vzorcích přítomnost bílkovin z prasat. Přítomnost organických zbytků živočišného původu byla navíc potvrzena detekcí cholesterolu pomocí plynové chromatografie ve spojení s hmotnostní spektrometrií. Analýza detekovaných mikroskopických botanických objektů odhalila škrobová zrna několika rostlin (tj. dubu, orobince a trav). Na základě našich údajů předpokládáme, že keramické pánve z Ústí na Drim byly použity pro přípravu jídel obsahujících maso z běžných hospodářských zvířat v kombinaci s obilovinami a planě rostoucími rostlinami. The Late Neolithic palafitte site, Ustie na Drim, in the northern part of Lake Ohrid (North Macedonia), excavated in 1962, offered ceramic fragments of large, flat, elongated pans. These artifacts could be dated by relative chronology to roughly around 5200–5000 BC. According to their shape and technological traits, the ceramic pans were probably used for baking. The attached materials on the surface of studied pan fragments were sampled for consequent chemical and microscopical analyses (i.e., analyses of starch, phytoliths, and microscopic animal remains). An immunological method revealed the presence of pork proteins in samples. The presence of organic residues of animal origin was, moreover, confirmed by the detection of cholesterol using gas chromatography coupled to mass spectrometry. Analysis of detected microscopic botanical objects revealed starch grains of several plants (i.e., oak, cattail, and grasses). An interesting find was the hair of a beetle larva, which could be interpreted contextually as the khapra beetle, a pest of grain and flour. Based on our data, we suppose that the ceramic pans from Ustie na Drim were used for the preparation of meals containing meat from common livestock in combination with cereals and wild plants.

This presentation was made at the Association of Emvironmental Archaeology Spring Conference on Open Science on 24th April 2021. It explores reproducibility in terms of what reproducible research is in Environmental Archaeology, what the barriers are, and how we can do reproducible research.&nbsp

This presentation was given at the International Meeting of Phytolith Research on 7th September 2021. It introduces the FAIR phytoliths project that strives to improve the FAIRness of phytolith data for the phytolith community. It starts by explaining what FAIR is, what constraints there currently are on data sharing and what the benefits of implementing FAIR for phytolith data would be. It then goes on to explain the project - what has been done so far, our plan over the next year and also how the phytolith community can get involved. The powerpoint includes a script of the talk. There is also a video recording of the talk that can be found here:10.5281/zenodo.5475346. &nbsp

[spa] En los últimos años los estudios de microfósiles vegetales, y los fitolitos en particular, se han consolidado como herramienta indispensable para reconstruir las condiciones paleoambientales y la paleovegetación, así como para trazar la utilización y explotación de los recursos vegetales en el pasado. En este trabajo se abordan diversas cuestiones metodológicas considerando procesos de formación, composición, producción y preservación de estos microrrestos. Asimismo se incide en la importancia de entender tanto los procesos de formación como los procesos postdeposicionales que pueden haber afectado la preservación de los restos y que son cruciales en la interpretación del registro arqueológico. A través de una selección de casos de estudio articulados en tres ejes temáticos principales (reconstrucción de la paleovegetación, uso del fuego y primeras prácticas agrícolas y ganaderas), se demuestra su enorme potencial y variabilidad de aplicaciones. [cat] En els darrers anys els estudis de microfòssils vegetals i els fitòlits en particular s'han consolidat com una eina indispensable per a la reconstrucció de les condicions paleoambientals i la paleovegetació, com també per traçar la utilització i l'explotació dels recursos vegetals en el passat. En aquest treball s'aborden diferents qüestions metodològiques considerant el procés de formació, composició, producció i preservació d'aquestes microrestes. Així mateix s'incideix en la importància d'entendre tant els processos de formació com els processos postdeposicionals que poden haver afectat la preservació de les restes i que són crucials en la interpretació del registre arqueològic. A través d'una selecció de casos d'estudi articulats en tres eixos principals (reconstrucció de paleovegetació, ús del foc i primeres pràctiques agrícoles i ramaderes), es demostra el gran potencial i variabilitat de les aplicacions. [eng] In recent years studies of plant microfossils, and phytoliths in particular have emerged as an indispensable tool for reconstructing paleoenvironmental conditions and palaeovegetation and to trace the use and exploitation of plant resources in the past. This paper addresses several methodological issues considering formation processes, composition, production and preservation of this micro remains. It also stresses the importance of understanding both formation and post-depositional processes that may have affected the preservation of the remains which are crucial in interpreting the archaeological record. Through a selection of case studies related to three main themes (palaeovegetation reconstruction, use of fire and early farming practices), phytolith analysis demonstrates its huge potential and variability of applications.

Dust and grit are ingested by herbivores in their natural habitats along with the plants that represent their selected diet. Among the functions of the rumen, a washing of ingesta from adhering dust and grit has recently been demonstrated. The putative consequence is a less strenuous wear on ruminant teeth by external abrasives during rumination. The same function should theoretically apply to camelids, but has not been investigated so far. We fed six llamas (Lama glama) a diet of grass hay and a lucerne-based pelleted food in which fine sand had been included at about 8% of ingredients, for ad libitum consumption for 6 weeks. Subsequently, animals were slaughtered and content of the different sections of the gastrointestinal tract was sampled for the analysis of dry matter (DM), total ash, and acid detergent insoluble ash (ADIA, a measure for silica). Additionally, two of the animals were subjected to whole-body computer tomography (CT) after death in the natural sternal resting position. No clinical problems or macroscopic changes in the faeces were observed during the experimental period. The results indicate an accumulation of ADIA in the C3 compartment of the stomach complex, in particular in the posterior portion that is the equivalent of the abomasum in ruminants. By contrast, contents of the C1, from which material is recruited for regurgitation and rumination, were depleted of ADIA, indicating that the contents had largely been washed free of sand. The washing effect is an unavoidable side effect of the flotation- and sedimentation-based sorting mechanisms in the ruminant and the camelid forestomachs. In theory, this should allow ruminants and camelids to live in similar habitats as nonruminant herbivores at lower degrees of hypsodonty.

Recent investigations of an apparently ‘empty,’ partly disturbed Viking chamber grave in Denmark (Fregerslev II, dated around the mid-10th century CE) provided an opportunity to develop a novel multi-scale and multimethod analysis of burial and post-burial processes. To overcome the limitations of poor preservation of artefacts and bones, and the lack of a clear macrostratigraphic sequence, we integrated multi-proxy analyses of organic and inorganic materials to study the spatial architecture, burial, and post-depositional processes, including soil chemistry (inductively coupled plasma mass spectrometry - ICPMS, portable X-ray fluorescence, spectrometer - pXRF), soil micromorphology, archaeobotany (wood, seeds, fruits, phytoliths), palynology (pollen, non-pollen palynomorphs), and faecal lipid biomarkers. The results enabled the detailed characterisation,spatial analysis, and sequencing of burial deposits, and the identification of post-depositional factors responsible for the poor preservation of the burial. Soil, phytolith and pollen data indicated that the base of the grave was covered with a matting of plant material, and there was no wooden floor. Faecal biomarkers detected substantial amounts of faecal matter, most probably originating from horse faeces, suggesting that a horse died in situ, and trace amounts of pig faeces, which are more likely to have been trampled into the grave. Enriched phosphorus concentrations could be linked to the bodies in the northern and southern sector of the grave. Furthermore, enrichment in lead was found where metal objects were recovered. The findings from Fregerslev II show thatintegrating high-resolution approaches to the analysis of poorly preserved burial contexts can fundamentally transform archaeological interpretations.

Herbivory is fundamental in ecology, being a major driver of ecosystem structure and functioning. Plant Si and phytoliths play a significant antiherbivory role, the understanding of which and of its evolutionary context will increase our understanding of this phenomenon, its origins, and its significance for past, extant, and future ecosystems. To achieve this goal, we need a superdisciplinary evolutionary framework connecting the role of Si in plant–herbivore interactions, in global processes, and in plant and herbivore evolution. To do this properly, we should acknowledge and incorporate into our work some basic facts that are too often overlooked. First, there is great taxonomic variance both in plant Si contents, forms, and roles, but also in herbivore responses, dietary preferences, and in fossil evidence. Second, species and their traits, as well as whole ecosystems, should be seen in the context of their entire evolutionary history and may therefore reflect not only adaptations to extant selective factors but also anachronistic traits. Third, evolutionary history and evolutionary transitions are complex, resulting in true and apparent asynchronisms. Fourth, evolution and ecology are multiscalar, in which various phenomena and processes act at various scales. Taking these issues into consideration will improve our ability to develop this needed theoretical framework and will bring us closer to gaining a more complete understanding of one of the most exciting and elusive phenomena in plant biology and ecology.

Aquesta tesi doctoral investiga sobre el poblamiento prehistòric a l'alta muntanya dels Pirineus catalans occidentals, més concretament, al Parc Nacional d'Aigüestortes i Estany de Sant Maurici (Lleida). En particular, aquest treball de recerca es distingeix per presentar una proposta metodològica innovadora, que contribueix a l'estudi de l'ocupació humana de les muntanyes durant el Neolític. La metodologia arqueològica desenvolupada s'adreça a la detecció de les activitats productives realitzades per les comunitats agroramaderes prehistòriques, la seva gestió ambiental i el seu impacte en el medi. Amb aquest objetiu s'han analitzat els fitòlits procedents de diferents tipus de dipòsits sedimentaris. Aquestes microrestes són cossos silicis produïts per les plantes, que ens informen de la composició vegetal dels sediments. Els fitòlits son un bon indicador per a l'estudi de les activitats que les societats feien amb les plantes i la conseqüent generació de paisatges socials. L'anàlisi de fitòlits s'ha integrat en aquesta tesi com una eina per a l'estudi de les ocupacions prehistòriques en zones d'alta muntanya dels Pirineus per primer cop. A més, com a proposta d'investigació bioarqueològica integradora, els resultats obtinguts s'han interpretat tenint en compte altres restes biològiques presents als sediments analitzats, com ara els carbons, el pol·len, les diatomees o la matèria orgànica. Esta tesis doctoral investiga sobre el poblamiento prehistórico de la alta montaña en los Pirineos catalanes occidentales, concretamente, en el Parque Nacional de Aigüestortes i Estany de Sant Maurici (Lleida). En particular, este trabajo de investigación se distingue por presentar una propuesta metodológica innovadora, que contribuye al estudio de la ocupación humana de las montañas durante el Neolítico. La metodología arqueológica desarrollada se enfoca en la detección de las actividades productivas realizadas por las comunidades agropastorales prehistóricas, su gestión ambiental y su impacto en el medio. Para ello, se han analizado los fitolitos procedentes de diferentes tipos de depósitos sedimentarios. Estos microrestos son cuerpos silíceos producidos por las plantas, que nos informan de la composición vegetal de los sedimentos. Los fitolitos son un indicador de las actividades realizadas por las sociedades con las plantas y su impacto en el paisaje. El análisis de fitolitos se ha integrado como una herramienta para el estudio de las ocupaciones prehistóricas en la alta montaña de los Pirineos por primera vez. Además, como propuesta de investigación bioarqueológica integral, los resultados obtenidos en esta tesis se han interpretado en relación con otros restos biológicos documentados en los sedimentos analizados, como los carbones, el polen, las diatomeas o la materia orgánica. This Ph.D dissertation focuses on the prehistoric settlement at high mountain areas of the western Catalan Pyrenees, particularly, in Aigüestortes i Estany de Sant Maurici National Park (Lleida). More specifically, this research work distinguished by an innovative methodological approach, which contributes to the study on human mountain occupation during Neolithic. The archaeological method is focused to detect the activities carried out by these agropastoral populations, the natural resources exploited and the impact caused on environment. Different sedimentary deposits were studied, in order to analyse silica phytoliths. They are siliceous bodies produced by plants, used as a proxy for detecting human activities on plants and their impact on landscape. Phytolith analysis is integrated as a tool for studying the prehistoric occupations in the high-altitude areas at the Pyrenees for the first time. In addition, into an integrated bioarchaeological approach, the results obtained are interpreted taken into account other biological remains analysed in sediments, such as charcoal, pollen, diatoms and organic matter.

Aquesta tesi doctoral investiga sobre el poblamiento prehistòric a l’alta muntanya dels Pirineus catalans occidentals, més concretament, al Parc Nacional d’Aigüestortes i Estany de Sant Maurici (Lleida). En particular, aquest treball de recerca es distingeix per presentar una proposta metodològica innovadora, que contribueix a l’estudi de l’ocupació humana de les muntanyes durant el Neolític. La metodologia arqueològica desenvolupada s’adreça a la detecció de les activitats productives realitzades per les comunitats agroramaderes prehistòriques, la seva gestió ambiental i el seu impacte en el medi. Amb aquest objetiu s’han analitzat els fitòlits procedents de diferents tipus de dipòsits sedimentaris. Aquestes microrestes són cossos silicis produïts per les plantes, que ens informen de la composició vegetal dels sediments. Els fitòlits son un bon indicador per a l’estudi de les activitats que les societats feien amb les plantes i la conseqüent generació de paisatges socials. L’anàlisi de fitòlits s’ha integrat en aquesta tesi com una eina per a l’estudi de les ocupacions prehistòriques en zones d’alta muntanya dels Pirineus per primer cop. A més, com a proposta d’investigació bioarqueològica integradora, els resultats obtinguts s’han interpretat tenint en compte altres restes biològiques presents als sediments analitzats, com ara els carbons, el pol·len, les diatomees o la matèria orgànica. Esta tesis doctoral investiga sobre el poblamiento prehistórico de la alta montaña en los Pirineos catalanes occidentales, concretamente, en el Parque Nacional de Aigüestortes i Estany de Sant Maurici (Lleida). En particular, este trabajo de investigación se distingue por presentar una propuesta metodológica innovadora, que contribuye al estudio de la ocupación humana de las montañas durante el Neolítico. La metodología arqueológica desarrollada se enfoca en la detección de las actividades productivas realizadas por las comunidades agropastorales prehistóricas, su gestión ambiental y su impacto en el medio. Para ello, se han analizado los fitolitos procedentes de diferentes tipos de depósitos sedimentarios. Estos microrestos son cuerpos silíceos producidos por las plantas, que nos informan de la composición vegetal de los sedimentos. Los fitolitos son un indicador de las actividades realizadas por las sociedades con las plantas y su impacto en el paisaje. El análisis de fitolitos se ha integrado como una herramienta para el estudio de las ocupaciones prehistóricas en la alta montaña de los Pirineos por primera vez. Además, como propuesta de investigación bioarqueológica integral, los resultados obtenidos en esta tesis se han interpretado en relación con otros restos biológicos documentados en los sedimentos analizados, como los carbones, el polen, las diatomeas o la materia orgánica. This Ph.D dissertation focuses on the prehistoric settlement at high mountain areas of the western Catalan Pyrenees, particularly, in Aigüestortes i Estany de Sant Maurici National Park (Lleida). More specifically, this research work distinguished by an innovative methodological approach, which contributes to the study on human mountain occupation during Neolithic. The archaeological method is focused to detect the activities carried out by these agropastoral populations, the natural resources exploited and the impact caused on environment. Different sedimentary deposits were studied, in order to analyse silica phytoliths. They are siliceous bodies produced by plants, used as a proxy for detecting human activities on plants and their impact on landscape. Phytolith analysis is integrated as a tool for studying the prehistoric occupations in the high-altitude areas at the Pyrenees for the first time. In addition, into an integrated bioarchaeological approach, the results obtained are interpreted taken into account other biological remains analysed in sediments, such as charcoal, pollen, diatoms and organic matter.

This paper examines the contribution of microscopic multi-proxy approaches to the study of early husbandry practices and animal diet by integrated micromorphological, phytolith, and calcitic dung spherulite analyses of midden deposits at the three neighbouring Neolithic sites of Boncuklu (9th–8th millennium cal BC), Pınarbaşı (7th millennium cal BC) and Çatalhöyük (8th–6th millennium cal BC) in the Konya Plain, Central Turkey. The results reveal considerable chronological and contextual variation in human-animal inter-relations in open areas between different communities and sites. At Boncuklu, middens display well-defined areas where phytoliths and substantial accumulations of omnivore faecal matter low in spherulite content have been identified. By contrast, open spaces at the Late Neolithic campsite of Pınarbaşı comprise large concentrations of herbivore dung material associated with neonatal ovicaprine remains from spring birthing. Here, the deposits represent repeated dung-burning events, and include high concentrations of dung spherulites and phytoliths from wild grasses, and leaves and culms of reeds that, we suggest here, derive from fodder and fuel sources. Late middens at Çatalhöyük are characterised by thick sequences derived from multiple fuel burning events and rich in ashes, charred plants, articulated phytoliths – mainly from the husk of cereals, as well as the leaves and stems of reeds and sedges – and omnivore/ruminant coprolites, the abundance of the latter declining markedly in the latest levels of occupation. The application of this integrated microscopic approach to open areas has contributed to unravelling the complexity of formation processes at these sites, providing new insights into herding practices, diet, and the ecological diversity of Neolithic communities in Central Anatolia., This work was supported by the Arts and Humanities Research Council [grant number 1227582]; the British Institute at Ankara [Study Grant]; and the Horizon 2020 Marie Sklodowska-Curie action [grant number H2020-MSCA-IF-2015-702529]. This research was developed within the framework of the Çatalhöyük Research Project and the Boncuklu Project, and it was supported by an Arts and Humanities Research Council (AHRC) doctoral grant and a British Institute of Archaeology at Ankara (BIAA) study grant awarded to AGS. MP’s research received funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska Curie grant agreement H2020-MSCA-IF-2015-702529.

The analysis of microbotanical remains (starch grains and phytoliths) from food-related domestic contexts and artefacts has the potential to provide insights into daily plant preparation and consumption activities. In particular, pottery vessels offer an unparalleled comparative framework for the study of food preparation and consumption, since pottery is used for a variety of domestic food-related activities, including storage, processing and serving. This study illustrates the potential of microbotanical remains to provide a holistic approach to the plant food preparation and consumption cycle—from storage to disposal—through the analysis of starch grains and phytoliths from Late Minoan storage, cooking and serving vessels recently uncovered at the Knossian ‘neighbourhood’ of Lower Gypsades. The results show that starch grains and phytoliths are more abundant and diverse in cooking vessels, presumably reflecting a higher deposition of microbotanical remains as a result of the disturbance caused by cooking. The results further offer insights into Minoan storage and cooking practices at Gypsades, suggesting that cereals were stored de-husked in pithoi and, possibly, in palm leaf baskets, and later cooked together with non-staple plants. The virtual absence of microbotanical remains from serving vessels may be due to depositional factors and/or the fact that some of the vessels analysed in this study were used for serving/consuming liquids or animal products, and not plants., The project was made possible with funds provided by INSTAP (EH, GA, AB); Semple Fund, Department of Classics, University of Cincinnati (EH); ERC Grant No. 312785 (AB); Fell Fund, University of Oxford (AB); the British Academy Grant No. SG152915 (AB); and the BSA. While working on this manuscript, JJGG was funded by a Marie Skłodowska-Curie Individual Fellowship (MSCA 2015, European Commission Grant No. 704867) and a Juan de la Cierva Incorporación 2018 Fellowship (Spanish Ministry of Science, Innovation and Universities), and ET is currently a F.S.R. Research Fellow funded by the Universitè Catholique de Louvain.

The so-called husking tray is a pottery shape attested during the 7th and the first half of the 6th millennium BC in the Near East. These vessels are large trays with surfaces crossed by scored patterns. It has been hypothesized a functionality related to cerealprocessing and bread making, further supported by ethnographical and experimental evidence. The Neolithic site of Tell Sabi Abyad (northern Syria) has provided diverse ceramic material including storage vessels, as well as a wide range of macrobotanical remains such as hulled barley, emmer wheat, lentil, chickpea and flax. The results of use-wear and phytolith analyses from a selection of husking tray assemblages from the Late Neolithic settlement are discussed here. Use-wear distributions over their surfaces showed patterns related to the detachment of plant foods such as `bread-like¿ materials, according to experimentally-produced records. In turn, phytolith results indicated the nature of the plant material adhered to the vessel surfaces which is dominated by Pooideae grasses. Multicellullar or anatomical connected phytoliths from the husks of wheat and barley were common in these assemblages. Overall, these results suggests a functionality related to the processing of cereals into bread. This integrated approach further supports the hypothesis that husking trays were used for baking to better understand Late Neolithic culinary practices.

The Sodicho Rockshelter in the southwestern Ethiopian Highlands presents a unique site that contains sediments of Upper Pleistocene and Holocene occupation phases of hunter-gatherer communities. Excavations and previous geoarchaeological research provided a first 14C chronostratigraphic framework for the last 27 ka cal BP, which supports the hypothesis of a potential environmental refugium during the Late Glacial Maximum (LGM, ~21 ± 2 ka). Nonetheless, it is necessary to extend the preliminary interpretation of stone tool assemblages, and the geoarchaeological analyses carried out so far to provide in-depth information on prehistoric human behavior at the site under changing climatic and environmental conditions. In this study, we reinvestigate the complex stratigraphy and the paleoclimatic context of Sodicho in order to expand the knowledge about site formation, post-depositional disturbances, weathering influences, and the anthropogenic impact on the sediment deposits. Micromorphological observations and the determination of active pedogenic oxides offered a more detailed look at the microstratigraphic record in relation to shifting moisture conditions during the African Humid Period (AHP, ~15 − 5 ka). Sediment alteration and reworking are connected to the influence of sheet flow, biological activity, and human impacts such as dumping activity and site maintenance. A comparison with black carbon (BC) analyses and a qualitative phytolith ratio (quantification of dark and light phytoliths) provided evidence for variations in human fire intensity. Our collaborative and multidisciplinary approach demonstrates how the complex formation of a rockshelter site in a tropical setting with changing climatic and anthropogenic impacts can be tackled.

The present article discusses the integration of urban geoarchaeological and archaeobotanical data of a series of Dark Earth deposits situated in the alluvial valley of the Senne River in Brussels, Belgium. Due to their homogeneous character, their interpretation is a huge challenge for archaeologists. Through a case-by-case approach, a detailed picture of the sequence of different activities and (semi-) natural events, leading to the build up of Dark Earth at each individual site has been obtained. Among the activities, agricultural practices and waste management, which are rarely archaeologically recorded in urban contexts, have been identified. Despite being situated in a valley context, none of the sites presented an excellent preservation of the organic plant remains. However, through the integration of geoarchaeological and botanical data, the taphonomical history of the botanical remains could better be understood, allowing us to document the evolution of the environment surrounding the sites. Additionally, it has been demonstrated that the botanical study of Dark Earth units can also provide valuable information on vegetal consumption, in particular fruits. On a broader scale, this integrated geoarchaeologial and archaeobotanical study sheds some light on the process of urbanisation of the Senne alluvial valley between the 11th–12th and the 16th century AD.

During the past 25 ka, southern Ethiopia has undergone tremendous climatic changes, from dry and relatively cold during the Last Glacial Maximum (LGM, 25–18 ka) to the African Humid Period (AHP, 15–5 ka), and back to present-day dry conditions. As a contribution to better understand the effects of climate change on vegetation and lakes, we here present a new Predictive Vegetation Model that is linked with a Lake Balance Model and available vegetation-proxy records from southern Ethiopia including a new phytolith record from the Chew Bahir basin. We constructed a detailed paleo-landcover map of southern Ethiopia during the LGM, AHP (with and without influence of the Congo Air Boundary) and the modern-day potential natural landcover. Compared to today, we observe a 15–20% reduction in moisture availability during the LGM with widespread open landscapes and only few remaining forest refugia. We identify 25–40% increased moisture availability during the AHP with prevailing forests in the mid-altitudes and indications that modern anthropogenic landcover change has affected the water balance. In comparison with existing archaeological records, we find that human occupations tend to correspond with open landscapes during the late Pleistocene and Holocene in southern Ethiopia.

Vascular plants are able to conduct biomineralization processes and collect synthesized compounds in their internal tissues or to deposit them on their epidermal surfaces. This mechanism protects the plant from fluctuations of nutrient levels caused by different levels of supply and demand for them. The biominerals reflect both the metabolic characteristics of a vascular plant species and the environmental conditions of the plant habitat. The SEM/EDX method was used to examine the surface and cross-sections of the Calamagrostis epigejos and Phragmites australis leaves from post-industrial habitats (coal and zinc spoil heaps). The results from this study have showed the presence of mineral objects on the surfaces of leaves of both grass species. The calcium oxalate crystals, amorphous calcium carbonate spheres, and different silica forms were also found in the inner tissues. The high variety of mineral forms in the individual plants of both species was shown. The waxes observed on the leaves of the studied plants might be the initializing factor for the crystalline forms and structures that are present. For the first time, wide range of crystal forms is presented for C. epigejos. The leaf samples of P. australis from the post-industrial areas showed an increased amount of mineral forms with the presence of sulfur.

In the archaeological record, ash and charred organic material are the only indications of the type of fuel used by ancient societies to feed their fires. This potential source of information may help further understanding of past human behaviour in relation to fuel selection, applied type of fire and function of fires lit in hearths. This study examined ash from reference samples and ash and char samples recovered from an Iron Age peatland site in Vlaardingen, the Netherlands. Local availability and abundance made it possible for the occupants of the site to choose from different fuel resources. Peat and cattle dung were readily available, while wood was less abundant. Reference samples from various locations were collected to investigate the properties of ash. Different types of wood, peat and cattle dung were accordingly ashed and analysed. In total, two techniques were used, that is, chemical analyses (x-ray fluorescence (XRF)) for the determination of the elemental composition and microscopic studies on field images of these ashes, mounted on glass slides, to investigate phytoliths quantitatively (Si and Ca types), siliceous aggregates and spherulites. The properties of the archaeological samples were compared with these results. The archaeological char samples were used for identification and analysed using reflective microscopy to study structure and temperature by reflectance (%Ro). It provided the necessary information to determine the type of fuel used by the Iron Age farmers and obtain more information on the function of the present fire structures. The results are strong indications that Iron Age farmers used all available fuels, that is, peat, cattle dung and wood, to feed their fires. The integrated application of phytolith, geochemical and char analyses has a high potential for the identification of the fuel selected by ancient societies.

Located in the arid basalt desert of northeastern Jordan, the settlement of Jawa is by far the largest and best-preserved archaeological site in the region. The Early Bronze Age (EBA) settlement phase of Jawa (3500–3000 BCE) is characterized by a highly sophisticated water storage system made of a series of pools, dams, and canals. In addition, recent archaeological and geoarchaeological surveys have uncovered agricultural terrace systems in the nearby vicinity. In this study, four of these runoff terrace systems were investigated by detailed mapping. Additionally, thirteen sediment profiles from inside and outside the terrace systems were recorded and sampled. The examined samples were analyzed for bulk chemistry, texture, phytoliths, diatoms, and dung spherulites to supply information on the environmental and depositional conditions. The terrace systems were dated using optically stimulated luminescence (OSL). Ancient terrace agriculture was practiced on slopes, small plateaus, and valleys close to Jawa through the use of surface canals, which collected and diverted floodwater from nearby wadis or runoff from adjacent slopes. The terraced fields were usually arranged in cascades and comprised a system of risers, canals, and spillways. The terrace fills investigated yield OSL ages of around 3300 BCE, indicating that the terraces were constructed in the Early Bronze Age. The terrace fill sequences are composed of mixed unstratified fine sediments of local origin, reflecting low-energy fluvial deposition regimes. The phytolith record is dominated by Pooid grasses that include the most common Near Eastern cereals, such as wheat and barley. Increased phytolith concentrations in terrace fill sediments, as compared to samples from non-terrace deposits nearby, suggest increased plant growth and water availability within the terraces. Whether the terrace systems were used for growing food crops only or whether they were additionally used for grazing cannot be ascertained. Overall, quantitative phytolith analyses in arid environments are well suited to investigate temporal and spatial distributions of plant microfossil concentrations and their relation to human activity or paleoenvironmental conditions.

Wild cereals have been harvested all over the world by hunter-gatherer with evidences as much in South America as in Australia, North America and Subsaharian Africa. In some places there are still used for human consumption. The goal of this paper is to document phytoliths in inflorescence axis, and in kernels/inflorescences/bracts of several native Argentinian wild grasses in order to get an archaeobotanical comparative referential for the analyses of residues from both food plant processing activities and consumption. We could observe typical phytolith morphotypes from specific anatomical parts of grasses, but non-taxon specific, as well as non-diagnostic phytolith morphotypes, but characteristic of the phytolith association of a certain taxa. They all allow us to get a more complete view of the phytolith production for each specific taxon. Results obtained by Morisita Test-Past Program-suggest a trend to the organization at the level of subfamilies for the phytoliths production in the 14 species studied. Species of the genus Aristida and Cynodon show an intra-generic consistency in the production of phytoliths morphotypes per organ, and tend to be grouped in cluster analysis. In some species as Cynodon dactylon, Bromus catharticus, Aristida adscensionis, Sorghastrum pellitum and Paspalum dilatatum it can be noted a similarity in the morphotype production as much in inflorescence axis as in kernels/inflorescences/bracts. A morphological continuum between similar morphotypes could be also established, by comparing series of shapes within fragments of silicified plant tissue. Finally, we consider phytolith production from potential useful plant parts for human consumption, in a way as their presence alone, or associated with starch grain analyses, as showed by a previous work, could be used for regional dietary reconstructions. Our results from inflorescence/kernel phytolith production give us good expectation to be able to identify them in archaeological contexts. Fil: Babot, Maria del Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Arqueología y Museo; Argentina Fil: Musaubach, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Cátedra de Etnografía; Argentina. Universidad de Buenos Aires. Facultad de Filosofía y Letras. Museo Etnográfico "Juan B. Ambrosetti"; Argentina Fil: Plos, Anabela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina

Date palm (Phoenix dactylifera) can accumulate as much as 1% silicon (Si), but not much is known about the mechanisms inherent to this process. Here, we investigated in detail the uptake, accumulation and distribution of Si in date palms, and the phylogeny of Si transporter genes in plants. We characterized the PdNIP2 transporter following heterologous expression in Xenopus oocytes and used qPCR to determine the relative expression of Si transporter genes. Silicon accumulation and distribution was investigated by light microscopy, scanning electron microscopy coupled with X-ray microanalysis and Raman microspectroscopy. We proved that PdNIP2-1 codes for a functional Si-permeable protein and demonstrated that PdNIP2 transporter genes were constitutively expressed in date palm. Silicon aggregates/phytoliths were found in specific stegmata cells present in roots, stems and leaves and their surfaces were composed of pure silica. Stegmata were organized on the outer surface of the sclerenchyma bundles or associated with the sclerenchyma of the vascular bundles. Phylogenetic analysis clustered NIP2 transporters of the Arecaceae in a sister position to those of the Poaceae. It is suggested, that Si uptake in date palm is mediated by a constitutively expressed Si influx transporter and accumulated as Si aggregates in stegmata cells abundant in the outer surface of the sclerenchyma bundles (fibers).

The study of micro-objects, both inorganic and organic, which can be found associated to parchment or cellulose fibres of books and documents, or in the inks and the dirt, accumulated over the centuries between the pages, can unravel important information on the manufacture of the ancient documents, on their past vicissitudes or on the causes of aging and deterioration of the materials they contain. The results of a critical observation of micrometric objects and structures with a diagnostic or archaeological significance have in some cases been surprising. Apart from the curiosity that certain findings may or may not raise, what needs to be discussed is the fact that some chemical components, usually attributed to the manufacture of materials or the inks may instead have a particular origin and nature, and therefore lead, if not properly highlighted, to some erroneous diagnostics. Examples are given where the information obtained by means of scanning electron microscope imaging and Raman microscopy were coupled with dispersive X-ray microanalysis and Fourier Transform Infrared Spectroscopy.

Biological cycling of silica plays an important role in terrestrial primary production. Soil warming stemming from climate change can alter the cycling of elements, such as carbon and nitrogen, in forested ecosystems. However, the effects of soil warming on the biogeochemical cycle of silica in forested ecosystems remain unexplored. Here we examine long-term forest silica cycling under ambient and warmed conditions over a 15-year period of experimental soil warming at Harvard Forest (Petersham, MA). Specifically, we measured silica concentrations in organic and mineral soils, and in the foliage and litter of two dominant species (Acer rubrum and Quercus rubra), in a large (30 × 30 m) heated plot and an adjacent control plot (30 × 30 m). In 2016, we also examined effects of heating on dissolved silica in the soil solution, and conducted a litter decomposition experiment using four tree species (Acer rubrum, Quercus rubra, Betula lenta, Tsuga canadensis) to examine effects of warming on the release of biogenic silica (BSi) from plants to soils. We find that tree foliage maintained constant silica concentrations in the control and warmed plots, which, coupled with productivity enhancements under warming, led to an increase in total plant silica uptake. We also find that warming drove an acceleration in the release of silica from decaying litter in three of the four species we examined, and a substantial increase in the silica dissolved in soil solution. However, we observe no changes in soil BSi stocks with warming. Together, our data indicate that warming increases the magnitude of silica uptake by vegetation and accelerates the internal cycling of silica in in temperate forests, with possible, and yet unresolved, effects on the delivery of silica from terrestrial to marine systems.