Wood for Building: Woodland Exploitation for Timber Procurement in the Prehistoric and Protohistoric Balearic Islands (Mallorca and Menorca; Western Mediterranean)

Abstract: The study of timber wood and wood charcoal fragments from archaeological sites (aka anthracology) constitutes a relevant archaeobotanical field of research for both landscape reconstruction and the study of past people-woodlands interactions. Regarding this second research field, variables other than taxa are known to be a key to the social organization of woodland management. In this sense, wood diameter constitutes a core factor of fire management, fuel provisioning and both firewood and timber procurement. These wood uses are most commonly represented in the archaeological record by charcoal fragments (both dispersed in the sediment and/or concentrated in fire structures) due to the fact the wood experiences both mass loss and fragmentation during carbonization. So the original form of the wood used (trunk, branch, twig) is no longer recognizable. Different pith-location tools (PLT) have been proposed previously in order to virtually locate the charcoal fragment in relation to the central part of the stem or trunk (pith) where the used wood originally came from. Among them, PLTs based on trigonometry are proven to be the most reliable, but have not yet been extensively tested on referential datasets in order to establish reliable analysis of the accuracy of the measurement of the missing radius, margins of error and correction factors. In this study we present an experimental referential dataset for 7 different taxa, both angiosperms and gymnosperms. The first aim was to move forward on the establishment of the trigonometric tool by testing if it is also suitable and valid for all the woody species producing tree rings. The second purpose was to provide a ready-to-use tool to estimate the missing radius with an interval of confidence. Lastly we also tested the effect of the carbonization on two taxa. According to the results obtained, a measuring protocol, correction factors and guidelines to interpret the subsequent results are established. In addition, an R function is now available to estimate the real radius from the calculated one with PLTs.

Abstract: This paper reviews the past distribution of Aleppo pine woodlands in the Ebro Basin, Northeastern Iberia, from the Mesolithic to Modern times based on wood charcoal data. The aim is to detail the chronological timing and the drivers explaining the long-term presence of Aleppo pine woodlands and associated thermophilous flora. The available charcoal data support the early spread of Pinus halepensis during the Mesolithic (ca. 9000 cal BP) accompanied by Mediterranean trees and shrubs like Quercus sp. evergreen, Juniperus sp., Arbutus unedo, Pistacia lentiscus, Rhamnus/Phillyrea, Cistaceae, and Rosmarinus officinalis, as a local response to global climate change in the Early Holocene. During the arrival and the propagation of the Neolithic culture (ca. 7500–5500 cal BP), anthracological records, as well as regional palynological sequences, demonstrate the progressive replacement of an conifer-dominated open parkland by both Quercus sp. deciduous and evergreen woodlands in response to the Middle Holocene rise in temperature and humidity. This evidence, however, converges with the general idea that the presence and the spread of Pinus halepensis and associated scrubland have usually been attributed to the onset of landscape anthropization. The frequency of xero-thermophilous open scrubland and the use of Aleppo pine for fuel and woodcrafting progressively increased during the Bronze and Iron Ages, and especially in Ibero-Roman and Medieval/Islamic times, when the vegetation landscape in the Middle Ebro Basin was largely deforested as a consequence of increasing demographic pressure, grazing and the establishment of proto-urban centers.

Abstract: Iron Age archaeology in Europe and the Mediterranean often faces significant difficulties to establish precise chronological frameworks by means of radiocarbon dating due to the so-called Hallstatt Plateau. This problem worsens in those archaeological sites excavated decades ago with a lack of stratigraphic control of the objects recovered. The archaeological studies carried out in Iron Age funerary contexts from Mallorca (Balearic Islands) are greatly affected by these two distorting factors. Therefore, it has been difficult to establish an accurate chronology for the origin and abandonment of certain individualization practices, such as the use of wooden coffins in collective necropolises. The goal of this paper is to overcome these limitations and to define the most reliable chronological framework for this funerary phenomenon by applying a multi-proxy approach. Thus, the chronological information provided by the detailed typological study of the material culture associated with the wooden coffins was connected to the results obtained from an extensive series of new radiocarbon dating of the wooden coffins. In addition, a wiggle-matching analysis (different 14C dates for the same wooden object corresponding to individual tree-rings) was also conducted in some wooden coffins in order to enhance the precision of the radiocarbon dates. Accordingly, the direct and indirect chronological information show that the use of wooden coffins in Mallorca started around 800–750 cal BC and was abandoned at c. 350–300 cal BC.

Abstract: The pioneering nature of Mediterranean pines and their phytosociological role have been largely discussed in relation to different agents (e.g., edaphic, climatic or anthropogenic). In this context, Aleppo pine is one of the most widespread pine species in the Mediterranean basin, as it is especially adapted to climatic constraints, such as drought and high seasonality, and has a high tolerance for salinity and strong coastal winds. It is also well adapted to regeneration after anthropogenic landscape disturbances, highlighting its important after-fire regeneration rates. In this sense, phytosociological studies conducted in Mediterranean landscapes have found that this species' wide distribution is mostly due to its rapid regeneration after human landscape transformation, including fire, and the abandonment of agricultural lands. Aleppo pine is considered to broadly develop after human action in sclerophyllous formation, in which it would be scarce or absent without human intervention. Parallel, paleoenvironmental and archaeobotanical studies have attempted to trace these trends back to prehistoric times to investigate this species' role in Late Pleistocene and Holocene vegetation and evaluate the role of climate and human action in its diachronic dynamics. In this study, we present a compendium of anthracological, dendro-anthracological and archaeopalyonological data with the objective of (i) investigating the nature and distribution of Aleppo pine on the island of Mallorca and (ii) evaluating the possibility that human action could have resulted in the spread of this pine species during the first two millennia of permanent human occupation of the island (c. 2300 cal. BCE–1st-century ACE). Investigating these archaeobotanical datasets, as well as making comparisons with anthracological and paleoenvironmental studies in neighbouring Mediterranean zones (Iberia), allowed us to attest that Aleppo pine is a natural, pre-human component of the Holocene vegetation of the island, and it is especially well-adapted to coastal environments. Moreover, we describe the trends and characteristics of the human management of pine woodlands through anthracology and dendro-anthracology, suggesting that human action did not provoke widespread growth of Aleppo pine in Mallorca at the expense of other vegetation types during prehistory. Such processes, well-documented by current phytosociological studies, probably began at some unknown point after the Romanisation of the island.

Abstract: Aleppo pine (Pinus halepensis Miller) is present in the palaeoenvironmental records of Mallorca (Balearic Islands, Western Mediterranean) since the Early Holocene. It is also documented in the archaeological charcoal analysis (aka anthracology) of early prehistoric sites, but it was especially exploited at certain sites during the Late Iron Age. However, different woodland exploitation strategies cannot be deciphered purely through the taxonomical identification of charcoal fragments, so it is difficult to assess if the presence of Aleppo pine in archaeological assemblages is due to specific social management strategies (branches and/or trunks exploitation). Anthraco-typological methods, based on the measurement of charcoal-pith distance (allowing original wood diameters to be inferred) and ring width, have already been proposed for temperate species (Quercus petraea/robur) as a methodology to define the woodland exploitation of past societies and human impact on forest formations. However, such an approach yet to be set up for conifers growing in Mediterranean environments. In this study we have adapted the anthraco-typological methodology to conifer wood anatomy and evaluated its applicability on the archaeological charcoal assemblages of Aleppo pine, through complete dendrological analysis of the referential material. Our research is based on the systematic measurement of two different dendro-anthracological parameters on archaeological charcoal fragments: charcoal-pith distance and ring width. The results have been compared with the information on ring width and the growing conditions of modern trees in three different forest formations in Mallorca, representing the entire environmental variability of the Aleppo pine forests on the island. Trunk cores and wood discs of different diameter were measured in order to establish criteria to distinguish between both tree organs from the archaeological charcoal fragments. Analysis of this dataset has proved that anthraco-typological methods are applicable to Mediterranean conifers and to further interrogate pinewood exploitation in prehistoric Mallorca. Additionally, we have been able to question the formation of archaeological charcoal assemblages, identify various woodland management strategies and the human impact on woodlands during prehistory.

Abstract: According to radiometric dates and the current state of research, the Balearic Islands were not colonized by humans prior to c. 4420/4220 cal yr BP. Therefore, it is possible to know the natural evolution of the landscape of the Balearic Islands for the first two-thirds of the Holocene (c. 10,000 to c. 4300 cal yr BP). This study aims to improve our understanding of the respective roles of human societies and/or climate in the transformation of vegetation cover during the Late Holocene in this Western Mediterranean archipelago. The results show the importance and control of climate oscillations in the evolution of vegetation throughout the Early and Middle Holocene. Our data clearly show that the transformation of the landscape started before the first human settlements. In Minorca (north-eastern Gymnesian Islands), this upheaval occurred between 5825 and 4675 cal yr BP (fourth to third millennium BC), while in Majorca (the largest of the Gymnesian Islands) the transition is less well dated, oscillating between 7169 and 2535 cal yr BP. In the southern Pityusic Islands, observed changes in Ibiza are less pronounced and coincide with the 4.2 cal kyr BP climate event, synchronous with human colonization. The correlation between forest fires and rapid climate events, as well as the resilience of vegetation until the Middle Ages (tenth century) in Ibiza, suggest that the evolution of climatic conditions is the preponderant parameter for explaining Holocene vegetation changes on these islands.

Abstract: Charcoal analysis aims to study different aspects of forest management, techno-economical choices and their specific impact on past landscapes, as well as the impact of climatic events. However, at the present time, charcoal analysis is generally limited to the study of a list of taxa and their relative frequency, as the methods usually employed in dendrochronology to characterize past woodland, based on long tree-ring series, are not suitable for anthracological material. Today, the new challenge for charcoal analysis is thus to develop adapted dendrological tools. In this context, the aim of the ANR DENDRAC project “Development of dendrometrical tools applied to anthracology: study of the interactions between Man, resources and environments” was to characterize modern-day wood stands in accordance with historical woodland practices and convert dendroecological data into parameters adapted to charcoal analysis. The purpose of this study is to define the dendrological features with the help of the anthracological tools without explaining the observed differences between the sampled stands (given the stational variability, age and regeneration modes). The first step consisted in creating dendro-anthracological tools based on morpho-anatomical criteria that help to characterize growth, distinguish heartwood from sapwood and evaluate charcoal-pith distance. The second step involves characterizing three modern-day wood stands (coppice under standard, high forest and young stand formed by a mixture of seeded and coppice trees), defined by their structure, stand density and regeneration modes, using dendrological data measured on fresh wood material and modelled into anthracological data with the dendro-anthracological tools. In this way, anthracological types were defined for each wood stand, forming anthraco-typological models, which area useful for the interpretation of archaeological charcoal assemblages. Finally, an anthracological key is proposed to sort archaeological charcoal fragments in anthraco-groups before data processing.

Abstract: With this article we intend to explore a theoretical and methodological approach to energy procurement and consumption in prehistoric households through the archaeological record. To do so, we focus on a specific kind of archaeobotanical material, charred wood, and in a specific case study, the Bronze Age Naviform society of the Balearic Islands. We discuss different theoretical issues related to the study of energy consumption as socio-environmental arena of nature–culture interaction and apply the classic methodologies developed by the anthracological discipline (taphonomic interrogation of the samples and taxonomical identification) to approach the landscape practices related to firewood gathering and consumption in the megalithic Naviform households (so-called navetiforms). We present data from three of these structures in two different sites from the South of Mallorca. These datasets reveals a mosaic landscape in which the Naviform groups organized the firewood procurement in relation to their taskscape and landscape perception and organization. Sclerophyll and open vegetal formations dominated the landscape and provided the main energetic resources to the Naviform households. The cyclopean navetiforms constituted the locus in which the social life of the familiar group inhabiting them was organized and, it is in this context that the firewood practices revealed in the anthracological record can be interpreted.

Abstract: Paleoenvironmental and archaeological data show that Mediterranean landscapes result from long-term socio-environmental interactions. Mediterranean islands constitute a place of passage where the creation of cultural landscapes can be traced through colonization and anthropization histories. Palynological studies carried out in the Balearic Islands highlight a deep vegetation change from the mid- to late-Holocene, but the climate-environmental-human interactions are not fully understood yet. In this study, we aim to disentangle the causalities of landscape changes during the last six millennia using a multi-proxy approach on an off-site core for the first time in Minorca island. We find that, during the mid-Holocene, the climate was wetter than today with less rainfall seasonality than in the current Mediterranean. This climate, favoured the expansion of box formations and the predominance of forested formations with minimal anthropized conditions. First agropastoral activities appeared in the sequence between ca. 3500–2650 cal BCE in north-eastern Minorca, coinciding with other sporadic archaeological evidence (Cova dels Morts rock-shelter) which support the possibility of a pre-Chalcolithic discovery and frequentation of the island. We record deep environmental change during the third millennium cal BCE, reflected in the substitution of the former mesophytic vegetation by Mediterranean maquis formations dominated by wild olive trees, heathers, mastic and Cistaceae. We propose that maquis, garrigues and open-land vegetation were favoured by human action in a context of increasing climatic dryness and seasonality, promoting vegetation flammability and substitution of former mesic communities to more adapted termophilous vegetation. The comparison of our new record from Addaia with other pollen studies from the Balearic Islands highlights the resilience of mesic vegetation to climate change. This is shown by the survival of box formations to the increased aridification initiated at ca. sixth–fifth millennium cal BCE (ca. 7–6 cal kyr BP) in the Western Mediterranean which culminated at ca. fourth–third millennium cal BCE (ca. 5–4 cal kyr BP). Additionally, whilst sporadic human presence versus stable occupation are difficult to detect in archaeological records, the coupling with paleoenvironmental studies may offer new scenarios and information for human arrival in the Balearic Islands.

Abstract: En esta Tesis Doctoral se ha realizado un estudio de las relaciones entre el paisaje vegetal y las comunidades prehistoricas y protohistoricas de las islas de Mallorca y Menorca (Illes Balears, Mediterraneo occidental) a partir del analisis de restos arqueologicos de madera (carbon y madera no quemada). La aproximacion a este objeto de estudio de ha desarrollado en el contexto tanto de las relaciones sociedad-entorno de estas comunidades como de la dinamica de la vegetacion holocena en el Norte del archipielago balear. En este sentido, se han analizado tres tipos de materiales diferentes: restos de carbon disperso en el sedimento de yacimientos arqueologicos, restos de material constructivo calcinado en contextos arqueologicos y objetos confeccionados en madera. El trabajo se organiza en tres bloques. En el primero de ellos se define la aproximacion teorica y metodologica al registro antracologico desarrollada en funcion de los objetivos propuestos. La perspectiva del estudio parte del analisis de varias aproximaciones al registro antracologico desarrolladas por diferentes investigadores en los ultimos decenios. Esto se ha puesto en relacion al contexto del analisis arqueologico de las relaciones entre las sociedades humanas y su entorno. En este sentido, se ha analizado la division entre una “arqueologia cientifica” y una “arqueologia teorica”. En el caso del analisis de las relaciones sociedad-entorno, este escenario ha influenciado el desarrollo de los trabajos de la arqueologia ambiental y, mas concretamente, en la disciplina antracologica. Muchos de estos trabajos parten de la distincion heuristica entre naturaleza y cultura, dicotomia a partir de la que se han organizado muchos de los trabajos antracologicos. Este escenario ha dado lugar a una multiplicidad de denominaciones de la propia disciplina y a la division entre las antracologas y los antracologos entre una “perspectiva ambiental”, centrada en el analisis de la dinamica de la vegetacion, y una “perspectiva funcionalista” o “paleoetnobotanica”, centrada en el analisis de la gestion de “recursos naturales”. No obstante, ambas perspectivas antracologicas, asi como diversas voces de otras disciplinas de la arqueologia ambiental, han cuestionado estas divisiones en la ultima decada, manifestando la necesidad de desarrollar aproximaciones no dicotomicas en los estudios arqueobotanicos. En este sentido, en el primer bloque del trabajo se analizan todas estas cuestiones teoricas y metodologicas y se plantea una aproximacion al registro antracologico que permita desarrollar un analisis holistico y contextual de los datos antracologicos orientado al estudio integrado de la dinamica de la vegetacion y de las interacciones entre las poblaciones prehistoricas y protohistoricas con esta. En un segundo bloque del trabajo se presentan los datos obtenidos en los 10 yacimientos arqueologicos de ambas islas de los que se han analizado restos de madera y carbon. Estos yacimientos son Closos de ca’n Gaia, Hospitalet Vell, Cova des Pas, Ses Paisses, Son Fornes, Ca’s Canar, turriforme de Son Ferrer, Cometa dels Morts, Son Maio y La Punta. Finalmente, en el tercer bloque del trabajo se discuten los datos obtenidos en relacion a los objetivos y la aproximacion establecidos en el primero de los bloques. En este sentido, se ha realizado una compilacion de todos los datos antracologicos disponibles para el contexto geografico y cronologico del trabajo, tanto los presentados en esta tesis como los publicados en trabajos de otros autores. Para el analisis de este conjunto de datos se han aplicado diversas herramientas de analisis estadistico multivariable. Todo ello ha permitido establecer varias hipotesis interpretativas en relacion a los diversos aspectos contemplados. Por una parte, el conjunto de datos antracologicos ha permitido matizar la imagen de la dinamica de la vegetacion holocena en las islas de Mallorca y Menorca, identificando diversas particularidades en relacion a otros territorios del Mediterraneo occidental. Por otra parte, el analisis de los diversos usos de las plantas lenosas identificados (combustible domestico, material constructivo, materia prima para la confeccion de objetos, combustible en ceremonias funerarias y ofrendas florales de difuntos) ha permitido caracterizar las relaciones entre las sociedades naviformes, talayoticas y postalayoticas en relacion al paisaje vegetal y a las plantas lenosas.