Identifying activity areas in archaeological soils from a colonial Virginia house lot using phytolith analysis and soil chemistry

Environmental archaeology methods can uncover both house lot organization and economic adaptation practices when applied systematically in conjunction with traditional archaeological research. This is the first study to employ both phytolith analysis and soil chemistry to interpret activity areas on an archaeological site. The patterning in the phytolith and soil chemistry analyses from the site of Rich Neck Plantation, Williamsburg, Virginia, reveals a set of six activity areas in and around the 17th century house lot, demonstrating a degree of economic diversification generally attributed only to 18th century colonial economic and social transformations.     

One,two, three phytoliths: assessing the minimum phytolith sum for archaeological studies

The number of phytolith studies has increased steadily in the last decades in palaeoecological as well as archaeological research, and phytolith analysis is currently recognised as a proper area of expertise within archaeobotany. This has led towards a strengthening in the standardisation of the different steps involved in analysis; e.g. sampling strategies, laboratory extraction or processing of plant material/soils for the creation of reference collections. In spite of this, counting procedures remain one of the areas that could be further developed. The aim of this paper is to assess representativeness of phytolith count size in archaeological samples and specifically to assess whether an increase in total number of individuals counted influences the number or distribution of morphotypes observed. Two statistical tests are performed to evaluate the representativeness of count size: phytolith sum variability analysis (PSVA) and morphotype accumulation curve (MAC). The analyses show the relationship among the number of counted phytoliths, the variability (that is, the number of different morphotypes identified) and the stabilisations of the MACs. Results allow us to support the standard count size in phytolith studies, which ranges from 250 to 300 particles. Together with a quick scan, this strategy should produce a precise and clear phytolith assemblage for archaeological studies.     

Late Holocene Neotropical agricultural landscapes: phytolith and stable carbon isotope analysis of raised fields from French Guianan coastal savannahs

This paper summarizes phytolith analyses from four pre-Columbian agricultural raised-field sites of the coastal savannahs of French Guiana—Savane Grand Macoua, Piliwa, Bois Diable and K-VIII—and carbon isotope analyses from the first-named site. The combined phytolith and ¹³C isotope analyses evidence the transformation of the landscape from a relatively homogeneous wetland vegetation comprised of a mixture of C4 and C3 plants (the latter including Cyperaceae and other herbaceous monocots such as Marantaceae and Heliconia, Oryzoideae grasses, and other plants typical of frequently flooded areas) to the construction of raised fields that were dominated by C4 plants (maize and other Panicoideae grasses). Our analysis proves the utility of phytoliths for tracing the agricultural history of landscapes, showing that, as in other parts of the Central and South American lowlands, maize (Zea mays) was one important crop cultivated in raised fields. We also estimated the productivity of raised-field agriculture, showing that in combination with other subsistence activities, it certainly had the capacity to sustain sizeable populations.     

Rapid phytolith extraction for analysis of phytolith concentrations and assemblages during an excavation: an application at Tell es-Safi/Gath,Israel

A rapid phytolith extraction procedure is described, that allows phytolith concentrations and morphotype assemblages to be analyzed within hours. This procedure enables the results of these analyses to be used during an archaeological excavation, in order to better understand how plants were used. The new procedure was tested using a standard phytolith extract and two experimental phytolith-sediment blends and found to be both accurate and precise. The reliability of partial slide counting was evaluated and found to be as accurate and precise as existing phytolith quantification methods. The new extraction and counting procedures were applied to an archaeological site, Tell es-Safi/Gath, Israel. The results demonstrate how information on phytolith concentrations in sediments that are available from one day to the next, can be used during an excavation to more effectively document the local features of interest and obtain better information.     

Ethnoarchaeological study of phytolith assemblages from an agro-pastoral village in Northern Greece (Sarakini): development and application of a Phytolith Difference Index

Phytolith assemblages are analysed in an ethnographic agro-pastoral community in Northern Greece. A new method for analyzing the data, combined with the concentrations of phytoliths per gram sediment, helps to differentiate diverse uses of space in the village. The Phytolith Difference Index (PDI) contrasts the phytolith assemblages in sediment samples from the region around the village least affected by human activities with those in the village and its immediate surroundings. The PDI reveals that many of the samples are dominated by the input of the stalks of the domestic cereal, rye, which is used for food, animal fodder and roof thatching. The PDI also differentiates between dung from mules or donkeys with dung from free ranging cows and goats. Activity areas analysed include storage areas, stabling areas, animal enclosures, floors from living areas that were repeatedly swept, hearths and open areas between structures. The combined use of the PDI, together with phytolith concentrations and phytolith morphotype analyses, may prove to be useful for deciphering activity areas in archaeological sites of not only agro-pastoralists, but also pastoralists and hunter–gatherers.     

Stability of phytoliths in the archaeological record: a dissolution study of modern and fossil phytoliths

Opaline phytoliths are important microfossils used in archaeological and ecological research. Relatively little is known about the stability of phytoliths after burial. Under alkaline pH conditions they can dissolve, and mechanical disturbances can cause a loss of their more delicate appendages. Here we present an experimental study of phytolith stability (combination of solubility and abrasion). Modern and fossil phytoliths were extracted from wheat using new methods to minimize dissolution, and by burning in an oven. These assemblages were placed in a solution buffered to pH 10 and maintained under constant temperature and shaking conditions. The silicon concentrations in the solution were monitored once a week for 5 weeks. The phytolith morphologies in each assemblage were determined at the outset of the experiment and after 5 weeks. The results show that there are differences in stability between various assemblages. Modern inflorescence wheat phytolith assemblages are more unstable than those from leaves/stems. Burnt assemblages are less stable than unburnt assemblages, and a fossil phytolith assemblage about 3000 years old is more stable than the modern wheat assemblages. The results also show that individual phytolith morphotypes have different stabilities, and as a result of dissolution and abrasion, some morphotypes may resemble others. This study further shows that archaeological and/or paleo-environmental interpretation of phytolith assemblages may change with the assemblage’s state of preservation.     

Use of space in a Neolithic village in Greece (Makri): phytolith analysis and comparison of phytolith assemblages from an ethnographic setting in the same area

Phytolith analyses were conducted in a Pottery Neolithic village (Makri) of Northern Greece in order to reconstruct aspects of past human activities as a function of both space and time. The analyses of phytolith assemblages were based on a reference collection of modern plant phytoliths (Tsartsidou et al., 2007), as well as an ethnographic study in an agropastoral community (Sarakini) in the same area that showed that many phytolith assemblages are characteristic of the activities carried out in different locations within and around the village (Tsartsidou et al., 2008). The same approach was used for studying the phytolith assemblages in the Neolithic village of Makri, namely measuring phytolith concentrations, diversities of phytolith assemblages relative to control samples collected from samples outside the village and detailed analysis of various phytolith morphotypes. At Makri samples from floors and various constructions (i.e. pit, platforms) were analysed, as well as sediments from an open area inside the village. The results show that Neolithic Makri was a society with a mixed agricultural and pastoral economy. Wheat and barley were cultivated for food and fodder and free-range animals were raised in a village inhabited year round. Indoor areas were not clearly differentiated from outdoor areas inside the village. The phytolith assemblages in only one series of floors produced at a specific location over an extended period of time reflected the use of that space for cereal storage or food processing. The phytolith assemblages from all the other floors examined did not reflect the local activities, but rather the constructional materials used for producing the floors.     

Human impact around settlement sites: a phytolith and mineralogical study for assessing site boundaries,phytolith preservation,and implications for spatial reconstructions using plant remains

Defining the extent of human activity around settlement sites is of particular significance in archaeology as it may define peripheral activity areas and thus the site's boundary. In Near Eastern archaeology, site boundaries are usually defined by the presence of architectural and other macroscopic archaeological remains. Here we use the phytolith concentrations and morphotype assemblages, as well as changes in the mineralogical composition of the sediments in and around the small Iron Age site of Izbet Sartah in central Israel to determine the site boundaries. The site has a shallow stratigraphy and highly bioturbated sediments. Coincidental changes in the clay/quartz ratio and phytolith concentrations define the boundary between high and low impact anthropogenic activities. This boundary is generally some 20 m away from the architectural remains. In addition, we note that the phytoliths in the site's core show clear evidence of having been affected by chemical dissolution (i.e., diagenesis), while those in the vicinity of the site's boundary have undergone severe diagenesis. These observations indicate that phytolith diagenesis will affect site boundaries determination, as well as phytolith-based reconstructions of activity areas. We propose that phytolith preservation depends on the initial amount of available silica, the depth of burial with respect to the active root area of modern vegetation, and the presence of fresh phytoliths in the soil.     

中国北方史前遗址稻作遗存的植物硅酸体判别标准

利用植物硅酸体方法鉴定考古遗址中的栽培稻遗存,关键之一就是确立鉴定标准。通过对野生稻生长的环境背景进行综合分析,提出在中国北方地区,在全新世时期,特别是仰韶时代和龙山时代,不具备野生稻生长的气候条件;在考古遗址中发现的稻属植物硅酸体可以被看成是栽培稻的遗存。     

The phytolith archaeological record: strengths and weaknesses evaluated based on a quantitative modern reference collection from Greece

The phytolith record from archaeological strata is a powerful tool for reconstructing aspects of past human behaviour and ecology. Considerable insights into the problems and potentials of this record can be obtained by studying phytoliths in modern plants. We prepared a phytolith reference collection of modern plants mostly from northern Greece that includes quantitative information on phytolith concentrations (number of phytoliths per gram dry organic material) and morphological assemblages. Here we analyse this reference collection with the aim of evaluating the strengths and weaknesses of the archaeological phytolith record. The reference collection comprises 62 different plant taxa. Of them, 28 are trees, 1 conifer, 10 shrubs and 1 herb, 3 domesticated annual legumes and 19 monocotyledons. We demonstrate quantitatively the extent to which woody species, legumes and fruits of dicots contribute only small amounts of phytoliths to the sediments per unit tissue dry weight, while leaves of trees and shrubs produce significant amounts of phytoliths and grasses are prolific phytolith producers. We compare the data of this reference collection with a similar reference collection from another Mediterranean ecosystem (Israel). The comparison indicates that some aspects of phytolith production are probably genetically controlled, whereas others are environmentally controlled. We note that despite the fact that woody species produce few phytoliths per gram of tissue, their record can be most informative when taking into account other properties of the sediments. We also note that jigsaw puzzle-shaped phytoliths normally form in plants that grow in humid conditions, but may form in arid environments when the plants are irrigated. This study clearly shows the extent to which some plants can be under-represented and others over-represented in the phytolith record. Knowing the extent of this bias can greatly improve our interpretation of the phytolith record.     

Ethno-geochemical and Phytolith Studies of Activity Related Patterns: A Case Study from Al Ma’tan,Jordan

ABSTRACT

Understanding Neolithic sites in southwest Asia is often difficult because of the lack of preservation of organic remains and the effects of various taphonomic processes that alter the original record. Here, we use an ethnographic approach to test the potential of using plant phytoliths and geochemistry to aid our interpretation of southwest Asian Neolithic sites. Our study of a recently abandoned stone and mud constructed village in Jordan, shows that for certain activity types, phytoliths and geochemistry can help distinguish different construction methods and functions, particularly for burnt areas, animal use areas and where there has been the addition of a specific construction material. For features constructed from the same source materials distinctions are more problematic. Geochemical and phytolith proxies were individually effective in distinguishing activity areas and construction materials, but signals were diminished when the statistical analysis was run on both forms of evidence combined. It is therefore recommended that the data from plant phytolith and geochemical analyses are subject to separate statistical tests and that the two sets of results are used in combination to interpret archaeological sites and their uses.     

The ‘invisible’ product: developing markers for identifying dung in archaeological contexts

Dung is one of the most valuable resources in arid countries: traditional communities all over the world use it for heating, cooking, building and decorative purposes. It is commonly assumed that the same happened in the past, especially after the domestication of herbivores in the 11th millennium B.C. The presence and use of dung in archaeological contexts has been routinely studied through different techniques among which spherulites (calcium carbonates that form in animals guts) and small seeds assemblages’ analyses. However all the proxies considered so far to trace dung can be unreliable, especially when used singularly. After a review of the traditional methods used to trace dung in archaeological contexts, this paper presents the results of an ethnographic study on 11 modern dung cakes collected in northern India that were analysed for chemical, spherulite and phytolith content. Our results show that the lack of spherulites cannot be taken as absence of dung input and that the combination of phytolith and chemical signatures can be a reliable proxy for the inference of dung presence in archaeological contexts.     

河南登封王城岗遗址土壤样品的植硅体分析

作为分析古代人类与植物关系的手段之一,植硅体分析在研究考古遗址中的人类活动、栽培作物及加工方式等方面,都越来越显示巨大的潜力。对王城岗遗址部分土壤样品的植硅体分析发现,在城墙夯土、城壕填土乃至城墙附近灰坑的土壤中,植硅体的密度低可能与城墙建筑有密切关系;王城岗遗址中发现的水稻、谷子的植硅体,表明当时聚落内有这两种农作物,并可能在城墙附近进行了脱壳加工。     

Locally diagnostic phytoliths of wild rice (Zizania palustris L.) from Minnesota,USA: comparison to other wetland grasses and usefulness for archaeobotany and paleoecological reconstructions

Wild rice (Zizania spp.) is an important native grain of north-central North America, with spiritual and subsistence significance to many native peoples. Due to lack of suitable proxies, its past distribution and pattern of use are poorly known. This study demonstrates the diagnostic value of silica phytoliths from Z. palustris as a proxy tool to detect its past occurrence in a variety of paleoenvironmental and archaeological contexts. Our main findings are: 1) Dominant wetland grass species in Minnesota produce phytoliths distinct from Zizania phytoliths; 2) Closely related Leersia oryzoides produces a few Zizania-like phytolith morphotypes; however, these potential confusers can be identified based on 2-D and 3-D morphologies; 3) Z. palustris produces a wide variety of phytolith morphotypes, many of which are only found in certain parts of the plant (e.g., Inflorescence Type 1 from the spikelet); 4) Z. palustris produces 23 locally diagnostic phytolith morphotypes that can be used to determine the presence and abundance of wild rice in modern and paleo lake sediments; and 5) Wild rice phytolith Inflorescence Type 1 is the morphotype most likely to be observed in archaeological contexts, and may be unequivocally diagnostic for the genera Zizania.     

TAPHONOMIC OBSERVATIONS OF ARCHAEOLOGICAL WHEAT PHYTOLITHS FROM NEOLITHIC ÇATALHÖYÜK,TURKEY, AND THE USE OF CONJOINED PHYTOLITH SIZE AS AN INDICATOR OF WATER AVAILABILITY*

An investigation of wheat husk phytoliths from a midden deposit at Neolithic Çatalhöyük provided the opportunity to investigate the impact of taphonomic processes on conjoined phytolith size. Wheat husk phytoliths from a possible crop processing deposit were examined using three methods. The results indicate that the size of conjoined forms decreases significantly as a result of laboratory extraction and slide preparation. Observations of the phytolith layer in thin section show some of the depositional and post‐depositional processes affecting phytolith size. These results indicate that these taphonomic factors need further investigation before conjoined phytolith size can be used to infer past water availability and agricultural practices.     

Reconstructing late Holocene palaeoenvironments in Bangladesh: phytolith analysis of archaeological soils from Somapura Mahavihara site in the Paharpur area,Badalgacchi Upazila,Naogaon District,Bangladesh

Palaeoenvironmental reconstruction based on phytolith analysis of late Holocene-aged soils in and around the Somapura Mahavihara archaeological monastery site in the Paharpur area, Badalgacchi Upazila of Naogaon District in northwestern Bangladesh was undertaken. Results indicate five climate zones marked by alternatively cool and temperate events. The phytolith assemblages of Zones 1, 3 and 5 are clearly characterized by a higher proportion of Pooideae phytoliths. The climate indices for these zones are all greater than 50, indicating cooler climatic conditions. In contrast, the phytolith assemblages of Zones 2 and 4 are typified by a higher proportion of Panicoideae phytoliths; their climate indices are 42 and 44, respectively, indicating the presence of a warmer, more temperate climate. In general, the dominance of grasses over broad- leaved trees throughout the sequences suggests that generally cool to temperate and dry conditions with some cyclical variability persisted around Paharpur and the surrounding region throughout the Pala Dynasty from AD 730 to 1080. The question of whether these shifts in vegetation might be linked with El Niño Southern Oscillation events, and whether these might in turn have cultural responses, is raised.     

The status of phytolith analysis in the American tropics

Phytolith analysis is now sufficiently mature to provide an independent source of data in tropical paleoethnobotany and paleoecology. At the same time, ongoing studies of phytoliths from tropical plants and sediments are discovering new applications. There are, to be sure, problems in interpreting prehistoric plant use and paleoecology which cannot be addressed through phytolith analysis; some of the more important ones are listed. Through a review of recent studies in the New World tropics, this paper presents some contributions to, problems of, and prospects for phytolith analysis to inform the archaeological community about such issues as (1) the origins and dispersals of domesticated plants, (2) the development of tropical forest agriculture, (3) the uses of tropical plants in prehistory, and (4) the distribution and composition of past plant communities.     

周原遗址西周墓葬出土芦苇编织物的材料鉴定及用途研究

西周时期墓葬中有机质的葬具通常保存情况极为不佳,考古学信息不甚明确,因而墓葬研究中往往无法充分利用此类材料,但此类材料具有潜在的考古学研究价值。本研究以2017年度周原遗址齐镇发掘区墓葬内所出严重降解的织物为材料,利用显微技术观察残余的表皮细胞和植硅体形态,鉴定结果表明墓葬内所出织物为芦苇(Phragmites communis),符合先秦文献中对殓席的记载,主要根据《士丧礼》和《既夕礼》两篇内容,梳理了芦苇编织物在丧葬过程中的用法和可能的出土位置,以此进一步判断出土苇席的性质主要为卧席和抗席。     

Ancient agriculture and domestic activities: a contextual approach studying silica phytoliths and other microfossils in soils

Abstract

Based on microfossil and soil data, we discuss a different methodological approach to agricultural and domestic archaeological studies, taking two Formative sites in the north-west Argentinian high valleys (province of Catamarca) as case studies, independently of traditional datasets and historical analogies. As a result of our investigations we not only recognised the vegetal species cultivated in ancient fields (dated to c. AD 800) but also distinguished some of the agricultural practices, such as crop rotation and alternation, use of animal fertilisers and irrigation resources, as well as the abandonment of the site. From this perspective, corral episodes could also be distinguished. In residential enclosures, we obtained results concerning activity areas, the definition of floors and the identification of reoccupations.     

Investigating crop processing using phytolith analysis: the example of rice and millets

The application of crop processing models to macro-botanical assemblages has traditionally been used to interpret past husbandry practices and organisation of labour involved in crop-processing. Phytoliths offer an alternative method of analysis because they are durable in most environments, regardless of whether plant parts are charred, and the identification of plant types and plant parts allows them to be used in much the same way as macro-botanical remains. Indeed macro-remains and phytoliths are complementary datasets for examining the input of plant parts, such as crop-processing waste, into archaeological deposits. We outline crop-processing models in relation to macro-remains and then develop the framework for their application to archaeological phytolith assemblages. Rice and millet processing models are explored in relation to patterns expected in both macro-remains and phytoliths. The utility of these models is demonstrated with archaeological evidence from the site of Mahagara, an early farming site in North-Central India. The results indicate a way to employ phytoliths in archaeology which complements the fragmentary evidence available from plant macroremains.