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Diatomite deposits of the lacustrine Truckee Formation near Hazen, Northern Nevada, are of Miocene age (ca. 10.3 million years old) and consist of varved deposits within commercial mines. These exposed deposits have been primary source of paleontological samples of stickleback fish fossils (Gasterosteous doryssus) spanning 100,000 years. These samples have revealed stasis, rapid morphological and genetic evolution, and local extinction of G. doryssus against a background of changing diatom communities. Here, we draw on geological, limnological, anthropogenic, and bibliographical data to illustrate the geographic and paleontological context of the Hazen diatomite deposits. We include a stratigraphic section describing lithology and stickleback specimen frequency at a 1 mm resolution. This paper should help researchers identify patterns in fossil site distribution and better understand the geological processes that have shaped the area, spurring new sampling and future research.

The ecosystem services and immense biodiversity of Amazon rainforests are threatened by deforestation and forest degradation. A key goal of modern archaeology and paleoecology in Amazonia is to establish the extent and duration of past forest disturbance by humans. Fossil phytoliths are an established proxy to identify the duration of disturbance in lake sedimentary and soil archives. What is not known, is the spatial scale of such forest disturbances when identified by phytoliths. Here we use phytolith assemblages to detect local-scale forest openings, provide an estimate of extent, and consider long-term forest recovery. We use modern phytolith assemblages of 50 Amazonian lakes to i) assess how phytolith assemblages vary across forest cover at 5 spatial scales (100 m, 200 m, 500 m, 1 km, 2 km), ii) model which phytolith morphotypes can accurately predict forest cover at 5 spatial scales, and iii) compare phytoliths with pollen to quantify their relative ability to detect forest cover changes. DCA results show phytolith assemblages could be used to differentiate low, intermediate, and high forest cover values, but not to distinguish between biogeographical gradients across Amazonia. Beta regression models show Poaceae phytoliths can accurately predict forest cover within 200 m of Amazonian lakes. This modern calibration dataset can be used to make quantitative reconstructions of forest cover changes in Amazonia, to generate novel insights into long-term forest recovery. Combining phytoliths and pollen provides a unique opportunity to make qualitative and quantitative reconstructions of past vegetation changes, to better understand how human activities, environmental and climatic changes have shaped modern Amazonian forests.

Waste management is paramount to town planning and ancient civilizations across the world have spent resources and mobilized labor for waste disposal and reuse. The study of waste management practices offers a unique window into the daily lives, social organization, and environmental interactions of ancient societies. In the Indus Valley Civilization, known for its urban planning, understanding waste disposal in rural settlements provides crucial insights into the broader socio-economic landscape. While extensive research has documented sophisticated waste management systems in urban Indus centers, little is known about practices in rural settlements. This gap limits our understanding of regional variations and rural-urban dynamics within the civilization. In this paper, using isotopic and microscopic proxies, we characterize the waste disposed of at the rural Indus settlement of Kotada Bhadli to reconstruct the sources of waste, including heated animal dung, and burned vegetation. We propose that rural agro-pastoral settlements in Gujarat during the Indus Era systematically discarded such waste in specific locations. By characterizing waste produced at Kotada Bhadli, we are also able to reconstruct the natural environment and how the natural and cultural landscape around the settlement was exploited by the residents of the settlement for their domestic and occupational needs. Our identification of the attention paid to waste disposal by the inhabitants of Kotada Bhadli adds significant data to our understanding of waste disposal as an insight into past lives. [ABSTRACT FROM AUTHOR]

Earth ovens are a ubiquitous feature of eastern North America, used throughout many cultures and periods, leaving a highly visible signature of habitational life. This study focusses on one of the four uniquely outsized earth ovens from the center of a woodhenge at Hopewell Mound Group, the type site of the Hopewell culture. Cleaned of artifacts and fire-cracked rock, this feature required specialized analysis to shed light on its function: macrobotanical methods of seed identification and wood charcoal analysis along with phytolith and soil micromorphological analysis. These analyses create a holistic picture of the earth oven, the woodhenge, and the nature of feasting and ritual at Hopewell Mound Group, along with a snapshot of the paleoenvironment. Results show ritual use of ash wood (Fraxinus sp.), Eastern Agricultural Complex seeds seasonally timed with a summer solstice ritual, and grass leaf phytoliths deposited deeper than the surrounding natural strata. Feasting at this site seems to be focused on feeding large numbers of people, as opposed to a small set of competitive elites. [ABSTRACT FROM AUTHOR]

Purpose: A prerequisite for the successful application of phytoliths in paleoenvironmental reconstruction is the correct interpretation of their environmental significance. In this context, key questions include: What magnitude of temperature/precipitation change is required to effect significant changes in surface soil phytolith percentages? When temperature/precipitation increases by a certain amount, what is the corresponding response of the percentages and assemblages of surface soil phytoliths? Additional detailed research is required to answer these questions. Materials and methods: We analyzed the phytoliths in 90 surface soil samples collected along the isohyets corresponding to the mean annual precipitation (MAP) of 400 mm (with the mean annual temperature (MAT) range of 3.24℃) and 600 mm (with the MAT range of 8.29℃) in Northeast China. Our objective was to determine the response of phytoliths to different temperature gradients. Soil phytoliths were extracted and identified using heavy liquid separation and microscope observations. Results: The DA of the phytolith percentages enabled the separation of samples collected along the two isohyets, with a total accuracy of 94.44%. MAT was the principal factor affecting the spatial distribution of phytoliths, with an explanation rate of 46.40%. In the surface soil samples collected along the two isohyets, the percentages of ELONGATE, ACUTE BULBOSUS, and PTERIDOPHYTE-TYPE morphotypes, were significantly negatively correlated with MAT, while the percentages of SQUARE were significantly positively correlated with MAT. However, the relationship between PAPILLATE percentages and MAT varied, showing both positive and negative correlations. A temperature gradient of ~ 3℃ was insufficient to significantly affect the percentages of SADDLE, BULLIFORM FLABELLATE, and BILOBATE. The phytolith index (C/W) can be effectively used to reconstruct the palaeoclimate in Northeast China. An MAP change of 200 mm resulted in significant changes in the percentages of ELONGATE, SADDLE, BULLIFORM FLABELLATE, and TRACHEARY (with the respective rates of 39.57%, 780.77%, 179.00% and 81.25%). However, the percentages of ACUTE BULBOSUS, SQUARE, RONDEL, BILOBATE, CRENATE, PTERIDOPHYTE-TYPE, SILICIFIED STOMATA, and PAPILLATE did not change significantly. Conclusions: Our results contribute to an improved understanding of the response of various phytolith morphotypes to temperature, and they provide a modern process basis for future phytolith-based paleoclimatic reconstruction in this region. [ABSTRACT FROM AUTHOR]

Background and aims Palm fossils are often used as evidence for warm and wet palaeoenvironments, reflecting the affinities of most modern palms. However, several extant palm lineages tolerate cool and/or arid climates, making a clear understanding of the taxonomic composition of ancient palm communities important for reliable palaeoenvironmental inference. However, taxonomically identifiable palm fossils are rare and often confined to specific facies. Although the resolution of taxonomic information they provide remains unclear, phytoliths (microscopic silica bodies) provide a possible solution because of their high preservation potential under conditions where other plant fossils are scarce. We thus evaluate the taxonomic and palaeoenvironmental utility of palm phytoliths. Methods We quantified phytolith morphology of 97 modern palm and other monocot species. Using this dataset, we tested the ability of five common discriminant methods to identify nine major palm clades. We then compiled a dataset of species' climate preferences and tested if they were correlated with phytolith morphology using a phylogenetic comparative approach. Finally, we reconstructed palm communities and palaeoenvironmental conditions at six fossil sites. Key results Best-performing models correctly identified phytoliths to their clade of origin only 59 % of the time. Although palms were generally distinguished from non-palms, few palm clades were highly distinct, and phytolith morphology was weakly correlated with species' environmental preferences. Reconstructions at all fossil sites suggested that palm communities were dominated by Trachycarpeae and Areceae, with warm, equable climates and high, potentially seasonal rainfall. However, fossil site reconstructions had high uncertainty and often conflicted with other climate proxies. Conclusions While phytolith morphology provides some distinction among palm clades, caution is warranted. Unlike prior spatially restricted studies, our geographically and phylogenetically broad study indicates phytolith morphology may not reliably differentiate most palm taxa in deep time. Nevertheless, it reveals distinct clades, including some likely to be palaeoenvironmentally informative. [ABSTRACT FROM AUTHOR]

The Ecuadorian Amazon holds more biodiversity than most other places on Earth. Palms are a particularly dominant component of the vegetation; however, it remains unknown to what degree the pattern has persisted through time. Here, we investigate the persistence of palm dominance through time and the degree to which past human activities (e.g., fire, cultivation, and forest opening) have affected changes in palm abundances across five regions of the Ecuadorian Amazon. We analyzed soil cores (40–80 cm depth) from each region for charcoal (evidence of past fire) and phytoliths (evidence of past vegetation change). The timings of fires (based on 14C radiocarbon dates), the occurrence, recurrence, and number of fires (based on charcoal presence and abundance in samples), and the amount of change in palm abundances (based on phytoliths) varied within and between the studied regions. The charcoal and phytolith results indicate the presence of low levels of past human activity at all sites. Our results show that patterns of modern palm hyperdominance found in Amazonian forests have not been persistent through time, and that even low levels of past human activities can affect palm abundance. [ABSTRACT FROM AUTHOR]

Quaternary geomorphological dynamics in the lowland tropics of South America can be described from the stratigraphy of hillslope colluvium and alluvial deposits. The analysis of sediments through the identification of depositional microfeatures and biomineralized microfossils, combined with their absolute dating by optically stimulated luminescence (OSL), allow the reconstruction of paleoenvironmental conditions. The objective of this work was to investigate the dynamics of depositional processes leading to colluvial deposition in the Araripe Plateau, Northeastern Brazil, from the analysis of stratigraphic sections, using phytoliths as indicators of paleovegetation and sediment micromorphology in the identification of depositional processes. The correlation of sediments ages, ranging from the OS3 to the OS2 (Last Glacial Maximum) with phytophysiognomy indices indicated the contribution and deposition of phytoliths from an arboreal/shrubby vegetation, replaced on the surface by grass vegetation. Periods of drier climates were correlated with LGM ages, with more open vegetation composed of grasses, in synchronously with less intense geomorphological events. The micromorphological analysis revealed that the characteristics of the deposits reflect more the action of depositional processes than pedogenetic ones. The correlation of phytolithic indices with micromorphology corroborated the environmental and geomorphological dynamics of the periods dated in the stratigraphic sections. [ABSTRACT FROM AUTHOR]

Raised garden beds were once among the most common Native American earthworks in eastern North America. Typically located on prime agricultural land, they are now among the rarest. However, previously unrecorded archaeological raised beds can still be uncovered, especially in more marginal agricultural settings. This chapter details the discovery of a previously unrecorded ancestral Native American ridged agricultural field site in Juneau County, Wisconsin, USA. The site was first identified in 2020 by the authors using publicly available historical aerial imagery and a recent lidar survey. Here we describe its confirmation as a ridged field archaeological site and emplace it within broader anthropogenic landscapes of Wisconsin. Methods described herein can be employed globally to locate and document raised bed agriculture. [ABSTRACT FROM AUTHOR]

Combustion features are routinely studied using micro-geoarchaeology in prehistoric sites, providing information on human social life. In submerged prehistory such features have not been studied from the microscopic perspective, and here we present a study of three combustion features from two submerged Neolithic sites from the southeastern Mediterranean: Atlit-Yam (ninth-millennium cal BP) and Neve Yam (eighth-millennium cal BP). Mineralogical analyses were utilized to detect heated clay while quantification of phytoliths, ash pseudomorphs, and dung spherulites allowed determination of fuel sources. Micromorphology was deployed to determine whether or not the features represent in situ combustion activities and to understand formation processes. Two installations from Atlit-Yam contain evidence for short in situ fire events that were fueled by wood and reached 700–900 °C. One installation from Neve Yam contains reworked deposits that bear evidence for combustion at 500–700 °C, includes remains of wood ash and livestock dung. However, this feature cannot be identified with certainty as an in situ combustion feature. This research shows that pyrotechnological, functional, and social information can be gleaned from underwater combustion features using a micro-geoarchaeological approach and techniques. [ABSTRACT FROM AUTHOR]

The study of pre-European Māori agriculture in New Zealand is hindered by a lack of direct evidence in the form of plant remains. Presented here are the results of pollen and phytolith analyses of three archaeological excavations at Auckland Isthmus, Cambridge, and northern Taranaki. All sites show landscape disturbance by people, and the discovery of pollen of the Māori-introduced cultigen Cordyline cf. fruticosa (ti), suggesting that this species had a wide geographic range, well beyond that considered climatically limited by early ethnographic accounts. The pollen of C. fruticosa can be identified in the Pacific Islands, including New Zealand which has several endemic Cordyline species. The study describes this pollen type and reviews the locations and types of both macro- and microfossils of C. fruticosa previously reported in the Pacific Island region. [ABSTRACT FROM AUTHOR]

As a plant kingdom and a biodiversity hotspot, Yunnan is a key region for our understanding of modern and past global changes in biodiversity and environment. As proxies of vegetation and climate, phytoliths have become increasingly important in ecological and paleoecological studies. In this study, phytolith analysis was carried out on samples of surface sediments from 70 lakes in western Yunnan, southwest China. These lakes are surrounded by modern vegetation types including broadleaved and coniferous forests, scrubs, grasslands, meadows, and alpine vegetation. The results of this study show that modern lacustrine phytoliths in western Yunnan are dominated by herbaceous phytoliths, among which Poaceae types are the most abundant. The 70 phytolith samples used can be divided into 4 groups, reflecting the major vegetation types from which samples were collected. The principal component analysis (PCA) and redundancy analysis (RDA) of the phytolith and climatic data of the 70 lacustrine phytolith samples showed that temperature and precipitation are the climatic parameters controlling the spatial distribution of phytolith assemblages in western Yunnan. Phytolith–MAT (mean annual temperature) and phytolith–MAP (mean annual precipitation) transfer functions were developed using weighted averaging partial least squares (WA-PLS), and both the MAT and MAP functions showed good performances (MAT: R2 = 0.67, RMSEP = 0.96 °C, MAP: R2 = 0.64, RMSEP = 140.4 mm). Our results also reveal that phytolith analysis is a useful technique offering reliable vegetation interpretation and climate reconstruction; thus, this study provides a basis for the vegetational and climatic interpretation of fossil lacustrine phytolith records in western Yunnan. [ABSTRACT FROM AUTHOR]

Purpose: The production of apple fruits in orchards or plants in tree nurseries is negatively affected by apple replant disease (ARD), worldwide. Our objective was to develop a method to counteract ARD without applying chemical soil disinfection. We tested if an addition of clays with high release of plant available silicon reduces ARD symptoms and a biochemical effect of silicon on the plant defence reaction occurs. Methods: In a greenhouse experiment, apple rootstocks 'M26' were grown for 8 weeks in a sandy replant soil, a heat disinfected control and a grassland soil (Grass) with and without amendment by bentonite and the clay blend Florisol®TM Profi (6 and 18%). The micromorphology of silica bodies (phytoliths) in roots and the phytoalexin concentration as a measure of the defence reaction of roots were analysed. In a second approach, the gene expression of ARD biomarkers involved in phytoalexin biosynthesis was determined after two weeks. Results: Normalised gene expression was significantly higher for the ARD soil with clay amendments compared to the ARD variant whereas phytoalexin concentrations were similar. Significantly lower phytoalexin levels were found in the heat disinfected and Grass variant, indicating less defence reaction than in the ARD variant. Clay amendment increased soluble silicon in the substrates and consequently silicon in the epidermis and vascular bundles, indicating high silicon accumulation. Plants grown in ARD and Grass with amendments showed improved growth compared to plants grown in the respective soils without amendments. Conclusion: The amendment of soil by clays rich in plant available silicon may counteract ARD symptoms. [ABSTRACT FROM AUTHOR]

The article presents the results of the first geoarchaeological study of the materials of Christian burials identified in the interior of the Middle Zelenchuk temple of the 10th century in the Nizhne-Arkhyz ancient settlement (Republic of Karachay-Cherkessia). The results of microbiomorphic (phytolith) and total phosphorus content analyses allowed us to reveal previously unknown features of the funeral rites of the multicultural and multi-ethnic Christian population of one of the largest cities of the North Caucasus in the Middle Ages. The differences in funerary practices between the 11th and 13th centuries became evident when studying even a small group of funerary complexes in which people of the same social group – representatives of the social elite of Western Alania – were buried. The geoarchaeological study showed an abundance of plant and animal organic matter in the burials. The complex analysis of archaeological materials and data obtained during the microbiomorphic study allowed us to conclude that members of the urban Christian community had several burial traditions: in stone boxes (tombs), in wooden frames, and a mixed ritual when a wooden structure was placed in a stone box. The presence of wooden bark particles in the burials seems to be related not so much to the material from which the burial structures were made as to the presence in the graves of bark or bast objects (bast caskets or boxes, birch bark amulets, toys, etc.). The tradition known from pagan Alanian burials of placing the head of the deceased on a “stone cushion” (more typical for male burials) was preserved in early Christian burials. In one of the four women’s graves studied, the analysis showed the presence of a “hay pillow.” Probably, before the burial, a ritual of washing the deceased was performed, as evidenced by the presence of diatoms and sponge spicules in the samples.

Archaeobotanical investigations at the site of Ona Adi in Tigrai were conducted during the 2013–2015 field seasons within the framework of the Eastern Tigrai Archaeological Project (ETAP). The site occupation spanned the Middle/Late Pre-Aksumite period (ca. 750/600 BCE) to the fall of the Aksumite Kingdom (ca. 700 CE), including the Pre-Aksumite to Aksumite transition (ca. 400 BCE–CE 1). The main objective of the study was to examine the agricultural economy in Eastern Tigrai during these periods and to evaluate the impact of social and cultural developments on the agricultural practices at Ona Adi. Recovered macrobotanical remains included wheat, barley, linseed, noog, lentil, and wild/weedy plants. In addition, evidence of finger millet was recovered along with tentative identifications of t'ef. The phytolith record shows evidence of grass processing, including morphotypes associated with Chloridoideae, Panicoideae, and Pooideae grasses. Results indicate that plants of both African and Southwest Asian origins were present in the region from the mid-eighth century BCE to the eighth century CE, but their relative importance varied throughout time in relation to socio-political changes at the regional level. Our data demonstrate a significant degree of continuity in the local agricultural economy, which remained largely unchanged even after the decline of Aksumite state. [ABSTRACT FROM AUTHOR]

Copyright of Memoria Americana is the property of Memoria Americana, Cuadernos de Etnohistoria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Context: Phytoliths constitute an important source of silicon in terrestrial and aquatic ecosystems. Schoenoplectus californicus (C.A.Mey.) Soják (Cyperaceae) is an important phytolith producer. Aims: We investigated the spatio-temporal variation in phytolith content of S. californicus in shallow lakes of the Pampean region, considering biomass and its relation to soil silicon content and lignin content. Methods: Calcination techniques were applied to quantify phytoliths. The biomass was estimated by destructive methods. Soil silicon concentration was determined through ultraviolet–visible spectrophotometry by means of the silicomolybdate method. For lignin determination, a fibre analyser and sulfuric acid were used. Key results: No significant differences were observed in the spatio-temporal analysis. There were no differences in the biomass estimation and in the phytolith per m2 contribution. Regarding soil silicon content, when the concentration was low, the phytolith production was low. Lignin content remained constant between sites. No correlation was observed between phytolith and lignin content. Conclusions: S. californicus is an accumulator of amorphous silica, generating a constant quantity of phytoliths over the years and between sites. The variation in some environmental conditions does not seem to be enough to be reflected in plant silica production. No relation between lignin and silica was found, perhaps due to their different roles in plant structure. Implications: The inclusion of other wetlands with more contrasting conditions may reveal the environmental constraints for the amorphous silica production. This study shows the importance of this community as a silicon source, and the implications of its displacement by other communities or urban development. Silicophytoliths constitute an important source of silicon in terrestrial and aquatic environments. Schoenoplectus californicus is an important silicophytolith producer. We investigated the spatio-temporal variation in silicophytolith content of S. californicus in three shallow lakes of the Pampean region, Argentina. S. californicus is generating a constant silicophytolith production over the years and between sites. This study shows the importance of this community as a silicon source, and the implications of its displacement by other communities or urban development. Photograph taken by M. De Rito. [ABSTRACT FROM AUTHOR]

This multidisciplinary study aims to decipher the impact of ancient charcoal production on past and present‐day soils in the northern Vosges Mountains. Soil observations in the field and laboratory were complemented by charcoal and phytolith studies on large thin sections, molecular analyses of organic pollutants, and phytolith analysis on bulk samples. The complex technosol platform records an ancient natural soil sequence buried by a human‐made platform on which charcoal accumulated. The current upslope soil is an entic Podzol. Palaeoecological data collected in the buried soil are reliable owing to low bioactivity due to soil acidity. Podzolisation predated the platform construction. The presence of ashes induced low soil alkalisation developed in the charcoal hearth remains and appears to have generated the migration of subsequent iron/clay/organic bands throughout the platform sediment and the buried soil. Charcoal studied in thin sections revealed mainly Quercus and Fagus taxa. Phytolith studies suggest that a less dense or degraded forest preceded platform construction, probably due to former woodland coppicing or earlier disorganised wood gathering. The specific distribution of polycyclic aromatic hydrocarbons sorbed on charcoal has persisted in soils throughout centuries, but we have no evidence that charcoal‐making activities contributed to diffuse global pollution. [ABSTRACT FROM AUTHOR]

Disturbances in tropical forests can have long‐lasting ecological impacts, but their manifestations (ecological legacies) in modern forests are uncertain. Many Amazonian forests bear the mark of past soil modifications, species enrichments, and fire events, but the trajectories of ecological legacies from the pre‐contact or post‐colonial period remain relatively unexplored. We assessed the fire and vegetation history from 15 soil cores ranging from 0 to 10 km from a post‐colonial Surinamese archaeological site. We show that (1) fires occurred from 96 bc to recent times and induced significant vegetation change, (2) persistent ecological legacies from pre‐contact and post‐colonial fire and deforestation practices were mainly within 1 km of the archaeological site, and (3) palm enrichment of Attalea, Oenocarpus and Astrocaryum occurred within 0, 1, and 8 km of the archaeological site, respectively. Our results challenge the notion of spatially extensive and persistent ecological legacies. Instead, our data indicate that the persistence and extent of ecological legacies are dependent on their timing, frequency, type, and intensity. Examining the mechanisms and manifestations of ecological legacies is crucial in assessing forest resilience and Indigenous and local land rights in the highly threatened Amazonian forests. [ABSTRACT FROM AUTHOR]

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phytoliths of biogenic silica play a vital role in the silicon biogeochemical cycle and occlude a fraction of organic carbon. The location, chemical speciation, and quantification of this carbon within phytoliths have remained elusive due to limited direct experimental evidence. In this work, phytoliths (bilobate morphotype) from the sugarcane stalk epidermis are sectioned with a focused ion beam to produce lamellas (≈10 × 10 μm2 size, <500 nm thickness) and probed by synchrotron scanning transmission X-ray microspectroscopy (≈100–200 nm pixel size; energies near the silicon and carbon K-absorption edges). Analysis of the spectral image stacks reveals the complementarity of the silica and carbon spatial distributions, with carbon found at the borders of the lamellas, in islands within the silica, and dispersed in extended regions that can be described as a mixed silica-carbonaceous matrix. Carbon spectra are assigned mainly to lignin-like compounds as well as to proteins. Carbon contents of 3–14 wt.% are estimated from the spectral maps of four distinct phytolith lamellas. The results provide unprecedented spatial and chemical information on the carbon in phytoliths obtained without interference from wet-chemical digestion. [ABSTRACT FROM AUTHOR]

Despite decades of archaeological research on Jamaica, little is known about how settlers influenced landscape change on the island over time. Here, we examine the impact of human occupation through a multi-proxy approach using phytolith, charcoal, and stratigraphic analyses. White Marl was a continuously inhabited village settlement (ca. 1050–450 cal yrs BP) with large mounded midden areas, precolonial house structures, and human landscape management practices. We have shown that the local vegetation at White Marl was directly affected by human settlement through the use of agroforestry and burning, and suggest that fire was used to modify vegetation. Manioc phytoliths were found throughout human occupation and are broadly associated with increases in evidence for burning, suggesting fire was used to modify the landscape and clear vegetation for crop cultivation. The phytolith assemblages relate to three distinct temporal vegetation phases: (1) the earliest occupation dominated by arboreal vegetation (pre-ca. 870 cal yrs BP); (2) a transition to palm-dominated vegetation (ca. 870–670 cal yrs BP); and (3) the latest occupation representing European colonization associated with a more open, grass-dominated landscape (after ca. 670 cal yrs BP). These transitions occur independent of changes in paleoclimate records, suggesting humans were the dominant driver of vegetation change. [ABSTRACT FROM AUTHOR]

Recent advances in the study of the antiquity and development of ancient Pacific Island agriculture have been made at sites across much of the region by the application of a range of microfossil techniques, namely analysis of pollen, phytoliths, and starch. Unlike in Melanesia and Polynesia, the application of these techniques in Micronesia is limited. Here we report on microfossil analysis of Micronesian archaeological pit deposits from Tarawa atoll, in the Gilbert Islands (western Kiribati), covering the last 1,800 years. Results show local pit cultivation of Cyrtosperma merkusii and Colocasia esculenta. Together with microfossils of other subsistence taxa, namely Cocos nucifera, Morinda citrifolia, and Pandanus tectorius, and 14C dated macrofossil charcoal of Artocarpus altilis, the evidence is consistent with the atoll subsistence tradition of Remote Oceania. Because plants have differential production and preservation of pollen, phytoliths, and starch, the study shows the value of using combined analyses of these microparts. [ABSTRACT FROM AUTHOR]

The lower Nhecolândia region, in the south of the Pantanal, contains thousands of shallow freshwater and saline-alkaline lakes isolated by sandy ridges. To understand the paleoenvironment, sediment cores from B02SR (freshwater) and 07SR (saline-alkaline) lakes were analyzed, employing a combination of 14C dating, microfossils, geochemical, elemental, and isotopic analyses. The 07SR core recovered Late Pleistocene sediments (~ 23,440 cal yrs BP), and the B02SR core Middle Holocene sediments (~ 6080 cal yrs BP). The base of the cores consists of bedded sands with no organic matter, sponge spicules, or diatoms. Phytoliths suggest the presence of cerrado vegetation with seasonal floods, suggestive of a periodically inundated distal floodplain. We interpret that the two lakes sustain perennial alkaline geochemical conditions between ~ 3080 and ~ 1330 cal yrs BP. The Lake B02SR transitioned to slightly acidic waters with low electrical conductivity from ~ 1330 cal yrs BP to the present, probably associated with a connection to ephemeral shallow or perennial channels. Lake 07SR maintained consistent water chemistry throughout the record, suggesting that an isolated drainage pattern remained unchanged creating persistent alkaline conditions. Our results suggest that lake chemical changes were spatially variable in lower Nhecolândia in the Holocene, which has implications for ecosystem services. [ABSTRACT FROM AUTHOR]

The three most abundant stable isotopes of Silicon (Si), 28Si, 29Si, and 30Si, all occur in plants. Isotope studies are a potential tool to explore uptake and function of plant Si, and it is a developing field. However, there is a lack of studies from natural environments, and species from the African continent, and all plant parts including reproductive structures. In this study, naturally grown papyrus plants were sampled from the Okavango Delta and divided into five organs, i.e. umbel, culm, scales, rhizome, and roots. Samples were analysed for TN, TOC, BSi, TP concentrations, and for Si isotopes. Each organ of papyrus is represented by two samples, one from juvenile tissue and one mature (apart from the roots where age is difficult to determine). The study confirms that papyrus is a high Si-accumulating species, with BSi ranging from 0.88 % in rhizomes to 6.61 % in roots. High Si precipitation in the roots leads to an enrichment in heavy Si isotopes in the residual mobile Si pool, as light Si isotopes precipitate in phytoliths in the roots, even though in this study phytoliths were identified for all organs except for roots. In papyrus, shoot organs gradually become enriched in heavy Si isotopes along the transpiration stream, with an increase in heavy isotopes from rhizomes to scales, culm, and umbel, same pattern that has been observed for other plants in literature. [ABSTRACT FROM AUTHOR]

The use of caves and/or rock shelters as a refugee for herds was a common practice in the Mediterranean area since the early Neolithic. Shepherds move the herds to pastures in higher altitudes, away from the settlements where the animals graze nearby the shelters where livestock is regrouped. Dung and residues produced during the occupation of these shelters were generally heaped and burnt to clean the site and prepare it for new usage, forming a characteristic deposit known as fumier. Fumier deposits are a great source of information to understand past herding practices including the animal's stabled, the management of the residues, the landscape, and the use of plants. In addition, they can provide a better understanding of site formation and postdepositional processes of archaeological sediments in caves and shelters including the impact of fire. Specific microarchaeological analyses are usually utilized to study fumier deposits. Here we present a multi-proxy approach that includes phytoliths, spherulites, ash pseudomorphs, and FTIR analyses, applied to the Neolithic levels of San Cristóbal, Los Husos II (Álava, Spain) and El Mirador (Burgos, Spain), located in the upper Ebro and Duero basins. This area in the north of the Iberian Peninsula constitutes a strategic location for the spread of the productive economy to the north, west, and interior of the Iberian Peninsula. Except for the lower Level XIII of San Cristóbal, where domestic activities were documented, our results showed similar behavior for the three studied sites, with no significant differences neither in terms of plant presence nor in the formation processes of the deposits. Up to seven and two possible complete stabling episodes were identified: three and two possible ones in San Cristóbal, and four in Los Husos II. Among the plants identified grasses of the C 3 Pooideae subfamily were dominant, probably representing local grasses. The combining presence of thermally altered phytoliths, spherulites, and ash pseudomorphs points that the stabling episodes burned for several hours with temperatures ranging between 500 °C and 700 °C. [ABSTRACT FROM AUTHOR]

Grass silica short cell phytoliths (GSSCPs), which are profusely produced within the grasses are often subfamily-specific and hence may act as one of the reliable plant proxies in deciphering eco-climatic conditions of an area. To assess how reliably grass phytolith morphs can capture the signal of rainfall variations of an area and to overcome the bias caused due to the redundancy and the multiplicity of GSSCPs, some Chloridoid grasses and soil samples from Maharashtra part of the Western Ghats along the west-east rainfall gradient are studied. The study reveals that S addle are the dominant morphotype produced by the members of this grass subfamily irrespective of the rainfall variations. Surface soil phytolith assemblage revealed that S addle morphs are inversely proportional to rainfall i.e., they increase with decrease in rainfall and vice versa. Based on this data, regions with MAP >2000 mm and <2000 mm could be separated in the northern Western Ghats. The results of the CCA and PCA also corroborated these observations. [ABSTRACT FROM AUTHOR]

The analysis of phytoliths is a recent addition to the geosciences and has found applications in various fields over the last few decades, including palaeoenvironmental studies in fluvial environments. As a developing field, it is essential to carry out studies aimed at creating a modern reference collection that fills an information gap on the production of phytoliths by plants in this environment. These studies are essential to increase the reliability and accuracy of phytolith research in reconstructing past vegetation patterns and compositions. This study is the first with the aim of creating a pioneer collection of phytoliths in fluvial environments of the Upper Paraná River, addressing woody eudicotyledon species of greater representation on the Três Ilhas (Three Islands) Archipelago. The phytoliths were extracted from the leaves of 51 species from the botanical collection of the Nupélia herbarium (HNUP) using the dry ashing extraction method. The analysis found that 21 plant families established on the site have some kind of silica accumulation and 34 species are producers of phytoliths with an identifiable shape and size (<5um). It was confirmed the Moraceae family produces Acute bulbosus (with ramifications), both considered diagnostic at family level. Confirming the current literature on the subject, redundancy of the spheroid ornate and spheroid psilate morphotypes was observed in woody plants. Although no new morphotypes were found, the information will contribute to studies on the evolution of fluvial geoforms. [ABSTRACT FROM AUTHOR]

Siliceous phytoliths are frequently used in archaeology and Quaternary paleoecology. In order to validate the potential of phytoliths to reconstruct the vegetation history in the Atacama Desert, Chile, we analyzed the occurrence and morphotypes of phytoliths in different organs of 97 plant species from 36 families living in the Coastal Cordillera of the Atacama Desert. Phytolith extraction was conducted by a new protocol using microwave digestion, which is rapid, provides clean and well preserved phytoliths and can be employed on plant material as well as sediments. Phytoliths were found only in Poaceae and Bromeliaceae. Although this limited occurrence restricts their value for the reconstruction of past vegetation diversity, their identification to sub-family and species levels provides detailed information on the occurrence of grasses and monocot flowering plants. These taxa are sensitive to environmental factors, such as climatic conditions, i.e. temperature and water availability. Comparisons of the phytolith morphotypes isolated here with those described in the literature suggest that the characteristics of the phytoliths in the Atacama Desert may not only depend on species and plant organs, but may also be dependent on the specific regional environmental conditions. [ABSTRACT FROM AUTHOR]

In 2011, in the Aleksandrov quarry (Kursk oblast, Russia), the Ryshkovo pedolithocomplex of the Mikulino (Eemian) Interglacial (MIS-5e) was studied. It includes three to four soil profiles separated by humified pedosediments. The lower soil is an eroded gray forest soil, the two middle soils ones are meadow soils at the bottom of the ravine and a soddy-podzolic soil on the paleoslope, and the upper soil is an underdeveloped soil with elements of forest pedogenesis. Morphological, physicochemical, and microbiomorphic studies of the pedolithocomplexes on the slope and in the bottom of the buried coastal ravine filled with colluvial and alluvial–colluvial sediments made it possible to reconstruct at least three pedogenic and four morpholithogenic stages in MIS-5e, which significantly detailed the event history of the interglacial. In the profile of the Ryshkovo pedolithocomplex, the buried humus horizon of the lower gray forest soil is clearly visible reflecting warmer climatic conditions of the first half of the last completed interglacial in comparison with its second half. Soil formation in trans-accumulative landscapes was repeatedly interrupted by erosion–accumulation processes, which reflects the instability (rhythmicity) of the climatic situation during the Mikulino interglacial and correlates well with detailed records from other geological archives. [ABSTRACT FROM AUTHOR]

Abstract Background Terrestrial ecosystems contain significant carbon storage, vital to the global carbon cycle and climate change. Alterations in human production activities and environmental factors affect the stability of carbon storage in soil. Carbon sequestration in plant phytoliths offers a sustainable method for long-term carbon stabilization. Carbon occluded in phytoliths (PhytOC) is a kind of carbon that can be stable and not decomposed for a long time, so it is crucial to conduct more in-depth research on it. Results We undertook a meta-analysis on PhytOC across global terrestrial ecosystems, analyzing 60 articles, encapsulating 534 observations. We observed notable differences in phytolith and PhytOC contents across various ecosystems. Bamboo forest ecosystems exhibited the highest vegetation phytolith and PhytOC content, while soil phytolith content was most prominent in bamboo forests and PhytOC content in croplands. Human activities, such as grassland grazing, had a lesser impact on soil PhytOC transport than actions like cutting and tillage in croplands and forests. Our study separated bamboo ecosystems, analyzing their PhytOC content and revealing an underestimation of their carbon sink capacity. Conclusions Notwithstanding our findings, phytoliths’ intricate environmental interactions warrant further exploration, crucial for refining ecosystem management and accurately estimating PhytOC stocks. This deepened understanding lays the foundation for studying phytoliths and the carbon sink dynamics.

An ash heap is defined as a specific object at an archaeological site, usually in the form of a separate hillock containing a layer of finely-dispersed greyish-yellow or ash-coloured soil. The existing assumptions about the formation and functional purpose of ash heaps, as special archaeological objects found near the Bronze Age pastoral settlements, have so far been poorly supported by scientific data. At the ash heap near the Sintashta fortified settlement of Stepnoye, Chelyabinsk Oblast, for the first time, large-scale and comprehensive studies were carried out on the structure of these deposits, their granulometric and geochemical composition, in combination with the analysis of plant macroremains, paleoparasites, microbiomorphic and palynological complexes, indicative bacterial groups, and keratinophilic fungi. Judging by the archaeological materials, it is patently obvious that this was a multifunctional object that developed over many centuries and played different roles at different stages. The results of the conducted analyses showed that the 45 cm thick “ash” horizon in the Stepnoye ash heap contains a significant proportion of a fine sand fraction, and not a silty fraction. An increase in the biophilic elements (predominantly calcium, as well as phosphorus and sulphur), accumulated mainly in the organic matter of faunal origin, was noted in the upper bench of the ash layer. However, the high concentration of phytoliths in the “ashy” deposits indicates that the layer was formed mainly as a result of the accumulation of a large amount of plant organic matter. The absence of charcoal and the scarcity of charred macroremains indicate that the deposited organic material was not burnt but decomposed naturally. The increased content of saprotrophic bacteria in the “ashy” layer also supports the natural decomposition of an organic matter. The composition of the phyto-lithic and pollen spectrum of the “ashy” horizon is not typical for the steppe of the south of Western Siberia, since it is dominated by a group of mixed herbs with elements of a ruderal flora, and not by cereals. All the data supports the hypothesis that the ash heap is the result of regular practice of cleaning of the floor and interiors of the buildings of the fortified settlement of Stepnoye. This is evidenced by the increase in the number of keratinophilic fungi, which decompose wool and hair and therefore accumulate in the occupational layer of the structures. Based on the results of the study, the hypotheses that the Stepnoye ash heap is a place of consolidated ash removal or composting of stable manure were rejected.

As a plant kingdom and a biodiversity hotspot, Yunnan is a key region for our understanding of modern and past global changes in biodiversity and environment. As proxies of vegetation and climate, phytoliths have become increasingly important in ecological and paleoecological studies. In this study, phytolith analysis was carried out on samples of surface sediments from 70 lakes in western Yunnan, southwest China. These lakes are surrounded by modern vegetation types including broadleaved and coniferous forests, scrubs, grasslands, meadows, and alpine vegetation. The results of this study show that modern lacustrine phytoliths in western Yunnan are dominated by herbaceous phytoliths, among which Poaceae types are the most abundant. The 70 phytolith samples used can be divided into 4 groups, reflecting the major vegetation types from which samples were collected. The principal component analysis (PCA) and redundancy analysis (RDA) of the phytolith and climatic data of the 70 lacustrine phytolith samples showed that temperature and precipitation are the climatic parameters controlling the spatial distribution of phytolith assemblages in western Yunnan. Phytolith–MAT (mean annual temperature) and phytolith–MAP (mean annual precipitation) transfer functions were developed using weighted averaging partial least squares (WA-PLS), and both the MAT and MAP functions showed good performances (MAT: R2 = 0.67, RMSEP = 0.96 °C, MAP: R2 = 0.64, RMSEP = 140.4 mm). Our results also reveal that phytolith analysis is a useful technique offering reliable vegetation interpretation and climate reconstruction; thus, this study provides a basis for the vegetational and climatic interpretation of fossil lacustrine phytolith records in western Yunnan.

Background: Terrestrial ecosystems contain significant carbon storage, vital to the global carbon cycle and climate change. Alterations in human production activities and environmental factors affect the stability of carbon storage in soil. Carbon sequestration in plant phytoliths offers a sustainable method for long-term carbon stabilization. Carbon occluded in phytoliths (PhytOC) is a kind of carbon that can be stable and not decomposed for a long time, so it is crucial to conduct more in-depth research on it. Results: We undertook a meta-analysis on PhytOC across global terrestrial ecosystems, analyzing 60 articles, encapsulating 534 observations. We observed notable differences in phytolith and PhytOC contents across various ecosystems. Bamboo forest ecosystems exhibited the highest vegetation phytolith and PhytOC content, while soil phytolith content was most prominent in bamboo forests and PhytOC content in croplands. Human activities, such as grassland grazing, had a lesser impact on soil PhytOC transport than actions like cutting and tillage in croplands and forests. Our study separated bamboo ecosystems, analyzing their PhytOC content and revealing an underestimation of their carbon sink capacity. Conclusions: Notwithstanding our findings, phytoliths' intricate environmental interactions warrant further exploration, crucial for refining ecosystem management and accurately estimating PhytOC stocks. This deepened understanding lays the foundation for studying phytoliths and the carbon sink dynamics. [ABSTRACT FROM AUTHOR]

The pedocomplex of a mesodepression with birch grove amid steppe has been studied in Novosibirsk oblast, West Siberia. This pedocomplex consists if the modern soddy solod soil (Planosol) overlying the buried organo-accumulative quasigleyic soil (Umbrisol). Several peaks of the maximum accumulation of phytoliths are seen in the profile of the soddy solod soil. The largest number of phytoliths is confined to the eluvial horizon. A significant part is represented by phytoliths of steppe grasses and rod-shaped phytoliths of dicotyledonous plants (forbs, legumes). The buried soil went through the steppe stage of development, as indicated by the predominance of phytoliths of steppe grasses, which was then replaced by the meadow-forest stage with an increase in the portion of forest and meadow grasses. The presence of diatom shells has been recorded throughout the entire thickness of the soil profile, including the buried soil. Their accumulation is associated with seasonal inundation of the mesodepression. [ABSTRACT FROM AUTHOR]

Elemental information carried by phytoliths plays a crucial indicative role in geochemical research. For instance, it serves as an indicator of the carbon pool effect in phytoliths and aids in the elucidation of silicon sources. However, early extraction methods for soil phytoliths primarily focused on obtaining their morphological and quantitative information, lacking efficient techniques for quantitative elemental analysis. In this study, we aimed to extract Si/Al information from soil phytoliths. Considering the need for complete extraction of phytolith, six extraction methods were developed and further by alkaline dissolution to determine Si/Al. Six methods were compared in terms of enrichment capacity, the weight of extracted phytoliths, and Si/Al differences. The results indicated that the addition of Ammonia-Catechol in the commonly used heavy liquid flotation method effectively improved phytolith extraction capability and the accuracy of Si/Al results. Additionally, the inclusion of an acetic acid step before alkaline dissolution further removed surface-adsorbed impurities and enhanced the analytical quality of Si/Al in phytolith. The comparison of the data in this study with other published data shows that our method is relatively robust. The improved method proposed in this study can provide a new idea for the quantitative analysis of other elements in soil phytoliths. [ABSTRACT FROM AUTHOR]

Background and aims: Phytolith analysis is a promising tool for paleovegetation reconstruction. However, compared with grass phytoliths, there are few studies that have classified the phytoliths of trees. Therefore, reliable definitions of phytolith types in woody plants and studies of representative woody phytoliths in soils are needed to provide an improved basis for reliable phytolith-based vegetation reconstruction. Methods: To explore the morphology of woody phytoliths and their preservation in soils, we described the phytolith morphology of 60 common broadleaved woody plants in the mid-subtropical zone of China, based initially on anatomical origin, and then on shape and finally on texture. We also for the first time established an index (R value) to explore the preservation of broadleaved woody phytoliths in soil in this region. Results: We divided the phytoliths of broadleaved woody plants into 6 major types and 35 sub-types. The 6 major types are: Epidermal Cell, Silicified stomata, Tracheary, Favose, Haircell, and Others. We found some degree of correspondence between different phytolith types and the parent plants. Fagaceae, Lauraceae, Magnoliaceae, Rosaceae, Anacardiaceae and Euphorbiaceae could be clearly distinguished from other families based on phytoliths. Only eight types of broadleaved woody phytoliths were present in the soils. Elongate attenuate, Elongate entire, and Polyhedral were better preserved in soils than the other types (Elongate entire attenuate, Tabular sinuate, Hair, Sclereid, and Favose). Conclusion: Our results provide a more accurate reference for broadleaved wood phytoliths in interpreting paleovegetation in this region. [ABSTRACT FROM AUTHOR]

A displaced paleosol layer presumably used for rice farming was found in the section under a rampart in the Southern Ussuriysk fortress. The paleosol was periodically flooded, as evidenced by diatoms from different environments. Bulliform rice phytoliths were found in the paleosol. The obtained range of radiocarbon dates made it possible to reconstruct the course of events. Based on a finding of B-Tm cryptotephra of the Baitoushan Volcano (946/947 CE), the rice field existed in the period between the middle of the tenth century and the construction of the fortress at the beginning of the twelfth century. The soil was transferred from the floodplain where soil profiles were formed in the Middle–Late Holocene under drier conditions than in the Middle Ages. The moisture increase in the Medieval Warm Period was favorable for the agriculture development, including the rice cultivation. The deposits formed during severe floods overlapped both the cultural layers and the paleosol of the rice field. It was likely one of the reasons for the end of rice cultivation along with the climate change towards cooling and a decrease in precipitation. [ABSTRACT FROM AUTHOR]

The selection of a non‐shattering phenotype is a pivotal change in the process of rice domestication. However, current research is heavily restricted by the preservation conditions of macro‐plant remains in early and middle Neolithic sites, as very limited well‐preserved rice spikelet bases could be retrieved. We present a non‐destructive method based on micro‐computed tomographic (CT) scanning, which could provide detailed visualization of the internal structures of charred spikelet bases and efficiently discriminate the shattering and non‐shattering phenotypes of rice spikelet bases according to the abundance of fusiform echinate phytoliths. It could be widely applied in different contexts, especially those poorly preserved specimens and tempers in pottery sherds, greatly improving our knowledge of rice domestication. [ABSTRACT FROM AUTHOR]

Phytoliths (siliceous structures) present in the plants have been employed in the fields of taxonomy and archaeology for many decades. Rostraria cristata is an economically important grass species (Poaceae) which accumulates silica in its different organs in the form of phytoliths. In order to understand the pattern of phytolith production and biochemical architecture of silica in R. cristata, leaf epidermis (blade) using the clearing solution method and different organs using the dry ashing method, X-ray diffraction and Fourier-transform infrared spectroscopy techniques were analyzed. Both abaxial and adaxial leaf epidermis showed the presence of acute bulbosus, rectangular sinuate and stomata phytolith morphotypes. Leaf including sheath and blade had the highest silica content. Characteristic phytolith morphotypes were present in different organs. A total of 34 phytolith morphotypes were present among which nine (9) were articulated and 25 were isolated forms. The most abundant were elongate scrobiculate (48.20%) in root and rectangular sinuate (26.16%) in leaf part. Other common phytolith morphotypes present in different organs of R. cristata were articulated elongate irregular, articulated elongate scrobiculate, acute bulbosus, and polygonal rondel etc. Leaf and synflorescence had the highest similarity based on presence/absence of phytolith morphotypes (Jaccard's similarity index). XRD studies revealed the presence of cristobalite, quartz, tridymite, zeolite etc. forms of silica in different organs. FTIR spectra showed that inplane stretching vibration of Si–C was unique to root, anti-symmetric stretching vibration of C–H was unique to leaf and Al2O3.SiO2 was found in synflorescence only. Our results show the characteristic pattern of phytoliths production in R. cristata. [ABSTRACT FROM AUTHOR]