Étude des macro-, méso- et micro-charbons du site épigravettien de Mezhyrich (Ukraine) : données taphonomiques et anthracologiques

This paper is the state of the art of charcoal signal studies (macro-, meso- and micro-charcoal) that have been carried out at the Epigravettian settlement of Mezhyrich. This work took part of the French ANR project “Mammouths”. Charcoal signals have been found in both natural and archaeological (pits and activity areas) deposits that have been sampled during the 2007–2008 archaeological excavations. This study aims at discussing the natural versus anthropic causes of those charcoal signals. Microscopic charcoal have been observed and quantified from loess sediments; they are probably the consequence of regional fire regimes. Charcoal signals found in archaeological layers would be mainly caused by human activities. The major charcoal signal is observed within the microscopic part of the archaeological sediments and thereby underlines the intensity of taphonomic processes. The identification of wood charcoal shows that birch and willow were located along the riverbanks, which provides further discussion of prehistoric fuel management in Pleniglacial context.     

Charred olive stones: experimental and archaeological evidence for recognizing olive processing residues used as fuel

After extracting oil from olives a residue is left usually referred to as the olive oil processing residue (OPR). This study explores the way in which ancient societies may have used OPR as fuel for fires to generate heat and the various issues that are related to the residues of this fuel. After drying, the high heating value and structure of OPR makes it an excellent and efficient fuel. Upgrading OPR further, through thermal conversion or charring, provides an even more efficient fuel (COPR), with a hotter and smoke free flame, a higher heating value and which is lighter in mass and thus easier to transport. After a fire is extinguished two types of remains of the fuel are left i.e. char and ash. Analyses on both remains, recovered from archaeological deposits, could be used as a source of information on fuel utilization. Laboratory experiments on charred modern OPR and stones show that by measuring their reflectance and analyzing their structure under reflected light microscopy, OPR and COPR can be distinguished in the charred material recovered from three archaeological sites in Greece and Syria. Based on these investigations it is suggested that on the three sites COPR was used as fuel. Ash, sampled together with the char, provides the possibility of investigating if other types of fuel were used, apart from OPR or COPR. On the investigated sites no ash was collected, but the analysis of the modern OPR showed that the properties of its ash could be used to distinguish it from other types of fuel. Ash from modern OPR and olive stones showed the presence of phytoliths. The often discussed issue related to the sharpness and smoothness of the edges of charred fragmented olive stones was investigated. The results showed that this is not a reliable criterion for recognizing olive oil production. It is recommended that in addition to the identification of the botanical material more properties of the remains of fuels should be analysed. To prevent destroying and losing char and ash as a result of excavation activities such as flotation and sieving, special measures have to be taken. The results show that analysing char and ash may provide valuable information on the (pyro)technology practised in ancient societies.     

Distinguishing rice (Oryza sativa Poaceae) from wild Oryza species through Phytolith analysis: Results of preliminary research

Asian rice is an important grain, not only in its homeland but in many areas of the world. Identifying rice in the archaeological record is a challenge, especially in the moist tropics, where organic materials preserve only when charred. Phytolith analysis, the identification of opaline silica bodies, provides an alternative method for identifying this important crop. Results of our research suggest thatOryza contributes phytoliths that are genus-specific, that bulliform characteristics alone do not permit separation of wild and domesticatedOryza in regions where species overlap, and that a number of phytolith types, especially silicified glumes, show promise for separating wild from domesticated forms. With further research it should be possible to identify rice through its phytolith assemblage in archaeological soils in the heartland of its domestication and use.     

A morphometric study of variance in articulated dendritic phytolith wave lobes within selected species of Triticeae and Aveneae

Morphometric analysis has proven to be an effective tool for distinguishing among phytolith assemblages produced by closely related plant taxa. Elongate dendritic epidermal phytoliths are produced in the inflorescence bracts of many cereal species. Under light microscopy, these articulated dendritic phytoliths produce wave patterns between the margins of the cells that are reported to have taxonomic significance. In this study we explore morphometric variance among the lobes of the wave patterns formed by the articulated dendritic phytoliths within selected species of cereals as a first step towards understanding the variance between species. We found that there is often significant variance in dendritic wave lobes among different accessions of a species, among the different types of inflorescence bracts of the species (glumes, lemmas and paleae), and among each bract type’s location on the inflorescence (upper, middle and lower third of inflorescence spike or panicle). We observed that shape morphometries are typically more reliable and require a smaller sample size for statistical confidence than size morphometries. We further observed that adequate samples sizes for analysis of several shape morphometries of articulated dendritic wave lobes are considerably smaller than those reported to be required for analysis of the same morphometries of individual or isolated dendritic phytoliths. To gain a preliminary sense whether there is potential for discriminating between taxa in light of the significant variance within species, we compared our data to archaeological material from the historical center of Brussels. We demonstrate that while there is considerable variance in the morphometries among accessions, bract types and inflorescence locations within each species, there may yet be potential for discriminating between cereal species in archaeological samples by the morphometries of their dendritic phytolith wave lobes. We present one possible paradigm for conducting such analysis on archaeological material.     

Tracing microfossil residues of cereal processing in the archaeobotanical record: an experimental approach

Interdisciplinary methodological approaches are fundamental for studying tool use and crop processing patterns in the archaeological record. Many archaeological studies of plant microfossil evidence, primarily those of phytoliths, starch grains and pollen, are concerned with processing methods which can be replicated through experimentally produced plant residues. However, most of these studies rely on crop identification through the presence or absence of such microfossils while giving little or hardly any weight to taphonomy and formation processes, which are critical for interpreting archaeological contexts. An investigation of experimentally produced phytolith and pollen assemblages provides the opportunity to evaluate the impact of cereal processing on both microfossils. Controlled experiments were conducted at the Museum of Menorca, Balearic Islands, Spain, for assessing microfossil taphonomy using Iron Age Talayotic tools and Hordeum vulgare (hulled barley) grown nowadays on the island. For dehusking, a sandstone mortar and a wooden pestle were used outdoors, whereas grinding took place indoors using a limestone quern and handstone. The results indicate that the size of multicellular or anatomically connected phytoliths decreases as a result of mechanical degradation suffered through processing activities, whereas the proportion of cereal pollen grains increases through these processes. Additionally, experimental samples from dehusking and sieving provided abundant evidence of floral bracts, and also of other plant parts and even different plant species, such as phytoliths from leaves and stems and non cereal pollen taxa, which were also to be found on the surfaces of the ground stone tools. These findings highlight the importance of integrating different lines of microfossil evidence and taking into account formation and taphonomic aspects, as well as the value of experimentally produced data for a better understanding of tool use and crop processing.     

Man and vegetation in northern Tenerife (Canary Islands, Spain), during the prehispanic period based on charcoal analyses

Changes in wood taxa used as fuel on the island of Tenerife from 250 B.C. to 1500 A.D. were studied, using charcoal analyses from three archaeological sites. These sites were occupied by “guanche” prehistoric peoples up to the conquest of the island by the king of Castille in 1496. It appears that the collection of wood by prehistoric people had not significantly altered the woody vegetation around the vicinity of the sites. The arrival of European settlers, however, brought new economic and cultural practices which were radically different from those of the prehistoric society.     

Assessing the importance of environmental factors to phytoliths of Phragmites communis in north-eastern China

Phytoliths have proved to be reliable indicators of environmental conditions both at present and in the past, and can provide evidence for the distribution of taxa or vegetation. Understanding the environmental significance of phytoliths within plants helps in drawing more reliable inferences about palaeovegetation and in reconstructing the palaeo-environment. The present study examined the relationship between phytoliths and environmental factors to assess the environmental significance of different types of phytoliths. Phytoliths were extracted from Phragmites communis growing in xerophytic and aquatic habitats at twelve sampling sites in north-eastern China and their implications for the environment were assessed using quantitative data mainly including phytolith concentration and environmental factors and statistical analyses. Principal component analysis (PCA) of several environmental factors (including the climate, micro terrain, and the physicochemical properties of soils) revealed that other factors being constant, P. communis phytolith concentrations were influenced largely by the average annual temperature and precipitation. Orthogonal experiment analysis and three-way analyses of variance of the concentrations confirmed the reliability of the results of the PCA. More specifically, the concentrations of the saddle and rondel types of phytoliths (the short-cell phytoliths) were closely linked to the average annual temperature whereas those of the elongate, lanceolate, and bulliform phytoliths (the non-short-cell phytoliths) were more sensitive to the variations in water status. The results contribute to further confirming the major environmental implications of phytoliths and, in turn, providing a reference for growth and development of wetland plants. Our findings also provide critical information that could help managers and policymakers assess and modify ecological restoration practices.     

Use of wood energy in the United States — An opportunity

The use of wood for energy — including the burning of solid wood and black liquor from pulping — has been growing at a rate significantly greater than that for all other uses such as lumber, pulp, or particleboard. In the United States, the end of most wood is not lumber or pulp and paper but feed for energy. In 1983, 155·5 M Mg of wood were used for energy. This could threaten to increase the price of wood for those other uses, or it can stimulate us to seek more creative ways of using untapped wood resources for fuel.On the basis of estimates of heavy wood energy use relative to other uses for wood, and estimates of continuing high costs for fossil fuels, we suggest here the feasibility of meeting the demand for fuelwood through small-scale cooperatives. Such an approach can improve forestry practices and can avoid unduly increasing the cost of wood for other end uses.     

Finger Millet processing in East Africa

Although archaeobotanical sampling and recovery programmes are a relatively recent implementation in East African archaeology, results from sites where they have been carried out follow a similar trend. This is one of abundant recovery of wood charcoal, but very little in the way of other macroscopic plant remains. Restricted archaeological evidence and ethnographic interviews show the importance of grains, in particular finger millet (Eleusine coracana), for the Bunyoro people of Uganda in pre-colonial times. It has been suggested that one of the possible reasons why finger millet is not being recovered in quantity from archaeological contexts is because the processing of this crop does not involve heating and hence there is not the chance of being deposited in charred form in the archaeological record. Recent ethnographic work on finger millet processing in Uganda shows that it is exposed to heat and potential charring during cleaning and preparation of the grain for either storage or cooking, and this regime is discussed in terms of its activities and products. These findings reinforce the need for archaeobotanists and archaeologists working in this region to look for other possible causes of the scarcity of macroscopic plant remains, and also the importance of considering integrated evidence for agricultural activity on prehistoric sites.     

Do soil phytoliths accurately represent plant communities in a temperate region? A case study of Northeast China

Modern soil phytoliths can potentially provide analogues for phytolith assemblages from archaeological and palaeoecological contexts. To assess the reliability of soil phytoliths for representing different plant communities, we analysed phytoliths in surface soils and parent plants at 65 sites representing five types of regional vegetation in Northeast China. The results demonstrated that surface soil phytolith assemblages could clearly differentiate samples from herbaceous and woody communities, and samples from Poaceae and non-Poaceae communities could be separated statistically. In addition, woody communities could be differentiated into a broadleaf-Poaceae community, a broadleaf-non-Poaceae community and a conifer and broadleaf-non-Poaceae community, except for some overlapping samples. Soil phytolith assemblages are thus able to differentiate regional vegetation types into different plant community types. In the present study, soil phytoliths represented about 30% of the phytoliths present in the aboveground vegetation. In addition, soil phytoliths from different communities reflected the aboveground vegetation with slightly different degrees of accuracy, and in addition different morphotypes exhibited different degrees of representational bias. Some morphotypes (e.g. rondel, elongate psilate, lanceolate) overrepresented the abundance of the associated plant taxa; morphotypes such as tracheid, conical epidermal, stomata and others under-represented the original plant richness; and other morphotypes, e.g. saddle, trapeziform sinuate, scutiform, were in good agreement with the numbers of plant taxa in the plot inventory. Thus, any quantitative palaeovegetation reconstruction using phytoliths should begin with the calibration of soil phytolith assemblages. We conclude that our findings provide improved phytolith analogues for different plant communities, with applications in palaeoenvironmental reconstruction, and they also provide additional insights into the mechanisms of phytolith production and deposition.     

美国俄亥俄州南部两种不同间伐强度对森林可燃物载量和碳的影响(英文)

本研究的目的是测定两种不同间伐强度下(70%和50%),美国俄亥俄州南部橡树混交林森林可燃物(包括枯落物、木本、草本和倒木)碳储量和其燃烧后可能释放的碳量。研究结果表明枯落物和木本碳含量显著高于草本部分。在50%、70%间伐和对照中,森林枯落物分别占了总的橡树混交林可燃物碳储量的36.6%,50.9%和66.0%。粗木质残体分别占了58.4%,48.0%和32.6%。小的木本和草本在总的森林可燃物中占据很小比例。在50%、70%间伐和对照三种情况下,总的森林可燃物分别是54.07t/ha、41.98t/ha和20.73t/ha。如果对这些森林可燃物进行燃烧,50%、70%间伐和对照中,其森林可燃物将释放碳量分别为90.39t/ha、70.19t/ha和34.66t/ha。虽然它们之间没有产生显著的差异,但和对照进行比较,间伐后仍产生了较多的一、二级森林可燃物。在50%、70%间伐和对照中,分别产生了25.08t/ha、23.47t/ha和14.38t/ha一、二级的可燃物。计划用火在燃烧这些可燃物成分时,在50%、70%间伐和对照中,可能会分别释放41.93t/ha、39.24t/ha和23.55t/ha碳。此研究对使用计划用火来减少引起森林火灾的森林可燃物具有一定的意义。     

Life Cycle Assessment of Greenhouse Gas Emissions from Marine Fuels: A Case Study of Saudi Crude Oil versus Natural Gas in Different Global Regions

The understanding of the greenhouse gas (GHG) emissions dimension in discussing the future of marine fuels makes it important to advance the current life cycle assessment (LCA) practice in this context. Previous LCA studies of marine fuels rely on general LCA models such as GREET and JEC well‐to‐wheels study. These models do not fully capture the various methane losses in the fuel supply chain. The primary goal of this LCA study is to compare the GHG emissions of heavy fuel oil and marine gas oil produced from Saudi crude oil to liquefied natural gas (LNG) in different global regions. A sensitivity analysis was performed to show how results may vary with non‐Saudi crudes. A secondary goal was to advance LCA of marine fuels by utilizing, for the first time, a set of bottom‐up engineering models that enable detailed analysis of specific oil and gas projects worldwide. The results show particular cases where LNG use in marine applications has a significant countereffect in terms of climate change compared to conventional marine fuels produced from a low‐carbon‐intensity crude oil. When the results are calculated based on a 20‐ versus 100‐year methane global warming potential, LNG appears noncompetitive for climate impact in marine applications.     

Climate, human palaeoecology and the use of fuel in Wadi Sana, Southern Yemen

This study integrates analysis of wood charcoal assemblages with climate proxies, palaeoenvironmental and archaeological data sets in hyper-arid Wadi Sana, Yemen, to address the availability and use of wood fuels by South Arabian hunter-herder groups from the Early Holocene (8000–7700 cal. b.p.) to Middle Holocene (6900–4800 cal. b.p.) periods. The Early Holocene environment, regulated by a stronger Southwest Asian monsoon, was moister than the present, providing a marshy winter grazing area for cattle herders, whose construction of hearths and food preparation strategies changed over time. This study provides an insight into long term stability of land cover and use as well as the dynamics of human contributions to landscape change. We suggest that complex environmental and cultural processes affect species availability, fuel choice and land use management. Despite environmental and economic changes in Wadi Sana, our dataset does not show changes in fuel choice from the Early to Middle Holocene.     

Cooking and Season as Risk Factors for Acute Lower Respiratory Infections in African Children: A Cross-Sectional Multi-Country Analysis

Background

Acute lower respiratory infections (ALRI) are a leading cause of death among African children under five. A significant proportion of these are attributable to household air pollution from solid fuel use.

Methods

We assessed the relationship between cooking practices and ALRI in pooled datasets of Demographic and Health Surveys conducted between 2000 and 2011 in countries of sub-Saharan Africa. The impacts of main cooking fuel, cooking location and stove ventilation were examined in 18 (n = 56,437), 9 (n = 23,139) and 6 countries (n = 14,561) respectively. We used a causal diagram and multivariable logistic mixed models to assess the influence of covariates at individual, regional and national levels.

Results

Main cooking fuel had a statistically significant impact on ALRI risk (p<0.0001), with season acting as an effect modifier (p = 0.034). During the rainy season, relative to clean fuels, the odds of suffering from ALRI were raised for kerosene (OR 1.64; CI: 0.99, 2.71), coal and charcoal (OR 1.54; CI: 1.21, 1.97), wood (OR 1.20; CI: 0.95, 1.51) and lower-grade biomass fuels (OR 1.49; CI: 0.93, 2.35). In contrast, during the dry season the corresponding odds were reduced for kerosene (OR 1.23; CI: 0.77, 1.95), coal and charcoal (OR 1.35; CI: 1.06, 1.72) and lower-grade biomass fuels (OR 1.07; CI: 0.69, 1.66) but increased for wood (OR 1.32; CI: 1.04, 1.66). Cooking location also emerged as a season-dependent statistically significant (p = 0.0070) determinant of ALRI, in particular cooking indoors without a separate kitchen during the rainy season (OR 1.80; CI: 1.30, 2.50). Due to infrequent use in Africa we could, however, not demonstrate an effect of stove ventilation.

Conclusions

We found differential and season-dependent risks for different types of solid fuels and kerosene as well as cooking location on child ALRI. Future household air pollution studies should consider potential effect modification of cooking fuel by season.     

‘It was maendeleo that removed them’: disturbing burials and reciprocal knowledge production in a context of collaborative archaeology

Recent decades have witnessed a growth in approaches to research and writing across anthropology's four fields that emphasize the need to respect alternative narratives and constructions of history, and to engage with anthropology's ‘publics’. These developments have generated more ethically responsible research and more inclusive writing practices. Nevertheless, the actual doing of cross‐cultural collaboration and knowledge production remains a challenge. In this three‐field (cultural, biological, and archaeological anthropology) study, we aim to capture, in writing, a process of collaborative fieldwork with Samburu pastoralists in northern Kenya that experimentally integrated ethnographic self‐scrutiny with a bio‐archaeological excavation involving human remains. In the process, we highlight the reciprocal knowledge production that this cross‐subdisciplinary, transcultural fieldwork produced.     

The interplay of ethnographic and archaeological knowledge in the study of past human subsistence in the tropics

Much of what is currently known or believed about how humans procured and produced food in the past stems from ethnographic and historical evidence of the subsistence practices of foragers and farmers. It is often difficult or impossible to relate archaeological evidence directly to the ethnohistorical record, although these two very different sources of data potentially complement each other. The potential of such complementarity is now being enhanced by the use of novel techniques, such as parenchyma, phytolith, and starch-grain analysis, for identifying fragmentary and amorphous organic remains retrieved from archaeological deposits, and by the use of the AMS (accelerator mass spectrometric) radiocarbon method to date very small samples, such as single seeds. More conventional ethnoarchaeological methods, by which field evidence of subsistence-related structures is compared with information derived from ethnographic and historical accounts, also continue to yield valuable insights into past food procurement and production. In this essay, the reciprocal relationship between archaeobotanical and ethnohistorical data is exemplified by examining (a) recent applications of novel analytical techniques in investigations of the antiquity of root and tuber cultivation in the American, African, and Southeast Asian tropics, and (b) the use of more conventional methods in the study of past forager subsistence in tropical northeastern Australia.     

New evidence for Neolithic rice cultivation and Holocene environmental change in the Fuzhou Basin,southeast China

A stratified profile of the Zhuangbianshan (ZBS) archaeological site (Fuzhou Basin, Fujian) was studied to investigate Neolithic era anthropogenic influence and associated environmental changes. Analysis of the archaeological sediments focused on phytoliths, palynomorphs and microcharcoal. Until now, a lack of direct evidence for agriculture has made it difficult to know if Neolithic cultures of this area relied on the exploitation of wild plants such as nuts and sago palm, or a combination of farming and foraging. Three types of rice phytoliths were found in ZBS archaeological deposits, providing robust evidence for rice farming as part of a broad-spectrum Neolithic subsistence economy centered on fishing and hunting. Chronologies based on AMS ¹⁴C dates and artifact typology place the earliest rice during the Tanshishan (TSS) Period (5,000–4,300 cal bp) followed by a shift to economic dependency on rice in the Huangguashan (HGS) Period (4,300–3,500 cal bp). The ZBS phytolith assemblage contains high frequencies of rice husk (peaked-shape glume cells) phytoliths, with far fewer leaf and stem types. This indicates late stage processing activities such as dehusking, implying a focus on consumption rather than rice production. High concentrations of charcoal in the Neolithic ZBS deposits indicate local human settlement and peaks in fire use. The ZBS pollen record also reflects human settlement and peaks in local forest clearance during the Neolithic. Forest cover was renewed when the site was temporarily abandoned following the Neolithic. Rapid formation of the Min River floodplain began ~2,000 cal bp in association with retreating sea level and intensifying anthropogenic influence. Prior to that, rice farming in the Fuzhou Basin was limited by the scarcity of wetlands suitable for agriculture.     

Environmental footprint of cooking fuels: a life cycle assessment of ten fuel sources used in Indian households

Purpose

Cooking energy is an essential requirement of any human dwelling. With the recent upsurge in petroleum prices coupled with intrinsic volatility of international oil markets, it is fast turning into a politico-socio-economic dilemma for countries like India to sustain future subsidies on liquefied petroleum gas (LPG) and kerosene. The aim of this paper is to evaluate and compare the environmental performance of various cooking fuel options, namely LPG (NG), LPG (CO), kerosene, coal, electricity, firewood, crop residue, dung cake, charcoal, and biogas, in the Indian context. The purpose of this study is to find environmentally suitable alternatives to LPG and kerosene for rural and urban areas of the country.

Methods

The study assessed the cooking fuel performance on 13 ReCiPe environmental impact categories using the life cycle assessment methodology. The study modeled the system boundary for each fuel based on the Indian scenario and prepared a detailed life cycle inventory for each cooking fuel taking 1 GJ of heat energy transferred to cooking pot as the functional unit.

Results and discussion

The cooking fuels with the lowest life cycle environmental impacts are biogas followed by LPG, kerosene, and charcoal. The environmental impacts of using LPG are about 15 to 18 % lower than kerosene for most environmental impact categories. LPG derived from natural gas has about 20 to 30 % lower environmental impact than LPG derived from crude oil. Coal and dung cake have the highest environmental impacts because of significant contributions to climate change and particulate formation, respectively. Charcoal produced from renewable wood supply performs better than kerosene on most impact categories except photochemical oxidation, where its contribution is 19 times higher than kerosene.

Conclusions

Biogas and charcoal can be viewed as potentially sustainable cooking fuel options in the Indian context because of their environmental benefits and other associated co-benefits such as land farming, local employment opportunities, and skill development. The study concluded that kerosene, biogas, and charcoal for rural areas and LPG, kerosene, and biogas for urban areas have the lower environmental footprint among the chosen household cooking fuels in the study.     

Four levels of patterns in tree-rings: an archaeological approach to dendroecology

This paper introduces a method detailing how tree-ring data from subfossil and archaeological wood can be interpreted in palaeoecological terms. On the basis of a literature review concerning the effects of known impacts on tree growth, an attempt is undertaken to provide a general theoretical framework for structuring and interpreting non-recent data where the ecological context is usually missing. The most important tools are dendrotypology and the systematic analysis of tree-ring patterns on four levels. These levels are: (1) ring-anatomical patterns; (2) impact patterns in ring width series at the single-tree level; (3) stand-dynamic patterns, i.e. patterns in ring width series on a stand-wide level; (4) complex patterns that are made up of consistent combinations of the other three pattern levels with each other or additional information. The distinction of these patterns allows the disentangling of different sources of influence on tree growth, which can also potentially be applied to archaeological wood. Several types of reaction to different categories of impact are defined. On a stand-wide scale, the phases of stand development can be reconstructed by identifying characteristic combinations of events. Thus, the range of possible interpretations can be narrowed down to a few possibilities, and sometimes only one. While the general concept is thought to be applicable to a wider range of regions and ecological settings, the presented discussion focuses on gap-phase dominated lowland forests and anthropogenic stands derived from such, which form the focus of central European dendroarchaeological research.