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Vegetation history and human activity during the last 6000 years on the central Catalan coast (northeastern Iberian Peninsula)
Abstract
In this paper, we present the results of four pollen diagrams obtained from the northeastern coast of the Iberian Peninsula. These data, together with a set of 11 radiocarbon dates, allow us to make some suggestions about human activity in this area mainly during the last 6000 years. We have established four main stages of this activity. Phase I (7000–3000 B.P.) shows some sporadic human clearance without qualitative and/or quantitative changes inside the natural woodland, except for slight oscillations in AP values. These clearances are synchronous with Neolithic and Bronze Age settlements. Phase II (3000–1500/1300 B.P.) demonstrates a different human action on the landscape along the Catalan coast. Sampling sites located in rich agricultural plains and close to urban centres show continuous woodland clearance during the Iberian period and especially during Roman times. In contrast, at boring sites far from these towns, the irregular and sporadic woodland disturbances continue, although these become more common. Phase III (1500/1300–850 B.P.) shows further woodland clearance fires along the coast. Pollen, archaeological and historical evidence allow us to relate this to the introduction of grazing in the coastal area, connected with seasonal transhumance between the littoral and mountain regions. Phase IV (850–300/150 B.P.) is characterised by the final clearance of woodland and the development of olive farming. During this phase the agrarian Mediterranean landscape was definitively formed.
... Wooded areas were also widespread, with abun-dant scrubs and holm oaks (Montaner et al., 2014;Castanyer et al., 2016;Ejarque et al., 2022). The reduction of forest mass indicates progressive deforestation during the Iron Age (e.g., Riera & Esteban, 1994;Piqué, 2002), linked to an increase in arable land (López et al., 2011). ...
... The results obtained from the dental mesowear analysis show that Caprinae and cattle consumed less woody plants in the second phase (450-325 BC) than in the first phase (550-450 BC). This scenario is consistent with the progressive reduction of the forest mass documented by palaeoenvironmental studies in the north-eastern Iberian Peninsula (e.g., Riera & Esteban, 1994;Piqué, 2002). ...
... The results are also consistent with feeding on eroded landscapes. Increased woodland clearance and land degradation in the region at that time have been documented by palaeoenvironmental studies (Riera & Esteban, 1994;Piqué, 2002). ...
Two major settlements were established in the Empordà region (north-eastern Iberian Peninsula) in the Iron Age (6th-2nd centuries BC), 15 km from each other: the Greek colony of Empúries and the Iberian city of Ullastret. This coexistence of two different ethnic entities in the same region – and the same environment – presents an opportunity to shed light on the variability of livestock practices in these settlements, as well as their relationship with the environment. For this purpose, in addition to traditional zooarchaeological approaches, we reconstructed the animal palaeodiet and seasonality of death using three different proxies: dental meso- and microwear analyses, and cementum analysis. The results of the study, conducted on caprine and bovine teeth from both sites, support the hypothesis proposed in previous works, namely that the environment was exploited differently depending on livestock species. Caprinae (sheep and goats) were fed in marginal areas and less suitable areas for agriculture while, in contrast, cattle grazed on rich grassland and/or in wetland areas. The combination of cementochronology and dental microwear suggests a lower consumption of grasses in summer for Caprinae and cattle. Seasonality results show that Caprinae were mainly slaughtered during spring and summer.
... First, progressive climate aridification in the north-west Mediterranean basin since the Late Holocene and the increasing impact of human activities-which in combination led to the expansion of sclerophyllous vegetation (i.e., evergreen oak) at the expense of Meso-Mediterranean deciduous species (i.e., deciduous oak)-is a well-known ecologic dynamic documented and discussed in an extensive literature (Allué et al., 2009;Azuara et al., 2015;Jalut et al., 2000Jalut et al., , 2009Mariotti Lippi et al., 2020;Pérez-Obiol et al., 2011;Reille and Pons, 1992;Revelles et al., 2022;Riera Mora and Esteban-Amat, 1994). In particular, the process had been ongoing on the Barcelona plain since the middle Bronze Age (approximately 3250 cal BP), according to the pollen sequence from Besos (Riera Mora and Esteban-Amat, 1994). ...
... First, progressive climate aridification in the north-west Mediterranean basin since the Late Holocene and the increasing impact of human activities-which in combination led to the expansion of sclerophyllous vegetation (i.e., evergreen oak) at the expense of Meso-Mediterranean deciduous species (i.e., deciduous oak)-is a well-known ecologic dynamic documented and discussed in an extensive literature (Allué et al., 2009;Azuara et al., 2015;Jalut et al., 2000Jalut et al., , 2009Mariotti Lippi et al., 2020;Pérez-Obiol et al., 2011;Reille and Pons, 1992;Revelles et al., 2022;Riera Mora and Esteban-Amat, 1994). In particular, the process had been ongoing on the Barcelona plain since the middle Bronze Age (approximately 3250 cal BP), according to the pollen sequence from Besos (Riera Mora and Esteban-Amat, 1994). We may assume that during the 1st century CE, the ecological niche of deciduous oaks was already limited to more humid areas in the hinterland hills (Carrillo et al., 2018), an idea that is in line with results obtained from the Roman pollen sequence from the moat of Barcino that suggest a scarcity of deciduous oak after the foundation of the colony (Bianco et al., 2023). ...
Funerary cremations in Roman times were important rites of passage that involved the use of fire to accompany the dead into the afterlife. In the present study, we investigated the wood fuel that was used to build cremation pyres and the foodstuffs involved in offerings and funerary feasts in a necropolis of Barcino (present-day Barcelona), dated to the 1st century CE and located at the Sant Antoni Market site. Our approach began with the analysis of wood charcoal and fruit/seed remains, which were preserved over time through carbonisation. These archaeobotanical remains offer valuable insights into the selection of woody species and the condition of wood logs used for cremations. Additionally, they shed light on the food composition of offerings and feasts in this area of the Mediterranean coast, where data on such practices are scarce.
The anthracological analysis of different combustion structures revealed that the principal taxon used for the stacks was evergreen oak, with deciduous oak playing a significant role during the initial use of the necropolis. Dendro-anthracological analysis indicated that medium to large diameters wood logs of deciduous oak obtained from mature individuals were commonly employed. Moreover, charcoal analysis suggested the use of pruning remains from fruit trees such as olive, grapevine, walnut, plums, and members of the apple family, providing evidence of arboriculture practices in the city. Additionally, various minor woody species (Aleppo and mountain pines, juniper, cypress, mastic, and rockroses) may have had several functions, including symbolic sensory aspects relating to smell and good flammability, the constitution of small objects or furniture placed on the stack (boxwood), and fire kindling or decoration (mastic, rockroses, honeysuckle, and laurustinus).
Carpological analysis indicated that the most abundant offerings and/or feast remains consisted primarily of cultivated fruits such as figs, walnuts, and grapes, while pulses and cereals were comparatively scarce or absent. Finally, a noteworthy quantity of Arbutus berry remains was recorded, marking the first occurrence of such findings in similar Roman contexts to date.
Keywords: Funerary pyres; Roman Barcelona; Wood fuel; Food offerings/feasts; Anthracology; Carpology
... In this framework, our study represents a novel analysis of the urban supply of biotic resources. On the other hand, several pollen sequences have been obtained from the Barcelona plain, such as from Besòs (Riera Mora and Esteban-Amat, 1994;Riera and Esteban, 1997), Mercabarna , and the Cagalell palaeolake (Riera Mora, 1990) (Fig. 1). These sequences facilitate an overall reconstruction of the vegetation dynamics on the Barcelona plain throughout the Holocene, although the resolution and precision for Roman chronologies are not always adequate. ...
... 172-173;Jalut et al., 2000;Azuara et al., 2015). In the case of the Catalan coast, however, this trend has been detected since at least the Bronze Age (Riera Mora and Esteban-Amat, 1994;Allué et al., 2017) and, thanks to this study, we can corroborate the fact that on the Barcelona plain this process was already underway prior to the foundation of the Roman colony. In fact, the limited frequencies of Quercus sp. ...
Woodlands are especially important spaces for city fuel provisioning. During Roman times urban centres carried out numerous activities with frequent wood-energy requirements, and as a result, they potentially impacted the composition of the surrounding forests.
Considering this premise, this study discusses the wood fuel economy and the configuration of the landscape around the Roman colony of Barcino (present-day Barcelona), located on the NW Mediterranean coast. We approached the topic starting from an analysis of wood charcoal fragments and pollen remains sampled from several rescue archaeological excavations along the perimeter wall of the Roman city, in order to shed light on the composition of the urban wood fuel exploited and the land cover of the suburban area between the 1st and the 6th centuries CE.
The charcoal analysis revealed that most of the fuel procured for Barcino came from holm oak woodlands, with Quercus ilex, Arbutus unedo and Erica arborea woods predominantly being harvested. Furthermore, the composition of the fuel charcoal debris appeared similar in the different excavation-sectors as well as constant through time, suggesting the existence of a fuel supply economy common to the whole city and sustainable woodland management to fulfil these needs.
Moreover, pollen analysis detected an important deforestation process in the ager of the city, accompanied by an increase in cereal and vine cultivation. In addition, either pollen and/or charcoal findings assessed the introduction of new fruit trees in the area (Castanea sativa, Juglans regia, Maloideae, Citrus sp., Punica granatum, Prunus sp.). Overall, these data suggest the fragmentation and ever-increasing shift of forested areas in the hinterland of the Barcelona plain, as well as on the hills.
... Thus, different palaeobotanical approaches have been applied to determine past plant communities. Data relating to the presence of plant communities come from published pollen records (e.g., Azuara et al., 2020;Carrión et al., 2007;Carrión et al., 2010aCarrión et al., , 2010bFletcher et al., 2012;Fletcher and Sánchez, 2008;González-Sampériz et al., 2017;González-Sampériz et al., 2020;Iriarte-Chiapusso et al., 2016;Jalut et al., 2000Jalut et al., , 2009Leunda et al., 2020;Pérez-Obiol et al., 2011;Revelles, 2017;Revelles et al., 2022;Riera et al., 2007;Riera and Esteban, 1994; among others) and charcoal sequences (e.g., 2021; Allué et al., 2009;Allué and Mas, 2020;Mas et al., 2022;Piqué et al., 2018;Ros, 1998;Ros and Vernet, 1987;Uzquiano, 2018, among others). These have served as the primary sources of reference in research of this type. ...
... Pollen records provide palaeoecological data on a large geographical scale, whereas anthracological records have more local significance (e. g., Asouti and Kabukcu, 2021;Chabal, 1992Chabal, , 1997Chabal et al., 1999;Kabukcu, 2018;Kabukcu and Chabal, 2021). Some palaeobotanical researchers suggest that it is not possible to propose a single palaeoecological model of the Holocene for the NE Iberian Peninsula (e.g., Allué et al., 2009Allué et al., , 2017bBurjachs and Riera, 1996;Carrión et al., 2010a;Piqué et al., 2021;Revelles et al., 2022;Riera and Esteban, 1994). Indeed, palaeobotanical data indicate the existence of a highly heterogeneous landscape. ...
The Mediterranean Basin is a global biodiversity hotspot, and oak tree species play an important role in it. Since the beginning of the Holocene (~11.4 kyr BP), the distribution of forests has not occurred uniformly, resulting in diverse types of vegetation landscapes. In this study, we used a maximum entropy algorithm (MaxEnt) to obtain the ecological niche model (ENM) of two sub-Mediterranean oak species, Quercus pubescens Willd. (pubescent oak) and Quercus ilex subsp. ilex (holm oak), both in the present day in the Iberian Peninsula and within a Middle Holocene (8.2–4.2 kyr BP) climatic scenario in the NE Iberian Peninsula. Moreover, we used the locations of Neolithic archaeological sites containing anthracological data to analyze the relationship between human occupations and oak habitats. Our results suggest that the two oaks have responded differently to the climatic conditions that have occurred, and show changes in both potential distributions. The palaeolandscape vegetation map shows a denser vegetation cover in the lowlands and a more open landscape in the highlands, with a higher dominance of Quercus pubescens in the septentrional areas, while Quercus ilex was more restricted to certain coastal areas. Temperature and precipitation factors, mainly seasonal climatic conditions, have had a greater impact on the distribution of vegetation than other factors. We found a good overlap between the ENM of the two oaks and the locations of the Neolithic sites analysed, and determined that the distribution of Neolithic archaeological sites is not random. The Neolithic populations in the study area depended heavily on the resources of the deciduous and evergreen sub- Mediterranean forest, although they also exploited the resources of the mountain pine forest. Neolithic sites distribution suggests that Neolithic human groups were aware of the potential of forests and probably gathered woody resources in their surroundings.
... Aquestes noves dades corroboren la necessitat d'actualitzar la síntesi sobre els canvis ambientals neolítics i la seva causalitat partint d'estudis interdisciplinaris. Riera, Esteban 1994;Riera et al. 2004Riera et al. , 2007 Drassanes 6,5 Barcelona Riera 1995Riera , 1996Riera et al. 2004Riera et al. , 2007 Cal Miras et al. 2010) evidencien que la vall del Madriu-Perafita-Claror (Andorra) constituïa un espai forestat (Fig. 3). La part alta de la serralada estava dominada per boscos de pins i els prats alpins eren pràcticament inexistents. ...
The reconstruction of the human impacts on the morphodynamics of river deltas in the long term is challenging. The ternary diagram of Galloway (1975) used to classify morphodynamics of deltas does not include direct human influence which is now affecting most of the deltas of the world. The study of human-dominated deltas requires specific approaches and consideration of human processes and morphologies in interaction with more commonly studied natural processes and morphologies. This study demonstrates how to combine different datasets from natural and social sciences to reconstruct long term temporal trajectories of hybrid urban deltas. The Francolí delta, associated with the UNESCO city of Tarragona, offers a perfect case study to identify the different steps of a wave-dominated delta leading to a human-dominated delta over a long-term perspective. Tarragona emerged in the 1st millennium BCE and became a significant port city in the Roman period. This study identifies the evidence of a semi-protected harbour built 2000 years ago that initiates the evolution of a hybrid urban delta towards a human-dominated delta. Until the end 19th c. CE, cyclical changes at the river mouth are observed due to natural fluvial and coastal dynamics while progradation stages are partly affected by anthropogenic structures over time. The 19th c. CE is a major turning point. Morphodynamics controlled by anthropogenic factors strongly increase while fluvial and coastal sedimentation is partly erased by dredgings. The systematic approach proposed for the Francolí delta can be standardised and applied to other hybrid urban deltas allowing better comparison between urbanised deltas.
The Early Neolithic lacustrine site of La Draga (Banyoles, Spain), where one of the first agri-cultural communities of the Iberian Peninsula settled between 7270 and 6750 cal. years BP, rep-resents an important school for bioarchaeological studies aiming to investigate the dialectic between human societies and vegetal environment in the past. In Lake Banyoles, the first evidences of human impact on the regional deciduous oak formations during the Mid-Holocene have been documented, thanks to a multi-scale approach that included pollen data from the archaeological site and from the associated lake sequence. In sector D located under the phreatic level, new methodologies of spatial analysis were applied in palynology, integrating non-pollen palino-morphs (NPPs) as good paleoecological indicators at a very local scale. The success of such methodologies allowed to describe the formation processes of the site, and evidenced patterns of social use of space by the Neolithic community in the past. In this work, a spatial approach in archaeopalynology is applied to Sector A of La Draga: in this sector, located at the highest topographical point of the site, the subaerial terrigenous sedimentation conditions have not allowed the conservation of organic matter and wooden elements, and a palimpsest of archaeological structures corresponding to different phases of occupation is observed. A total of 25 samples were analysed, from the horizontal sampling of three archaeological structures and two stratigraphic levels of the northern subsector, excavated between 2018 and 2021. The results of 51 horizontal samples from the southern subsector were also integrated to the analysis. The application of multivariate statistical analyses and spatial interpolation algorithms (IDW) enabled to identify the main climatic, taphonomical and anthropic factors associated to the formation of the horizontal pollen record in Sector A. In the pollen spectrum of Sector A, herbaceous plants dominate, as a result of direct and indirect human influence on the landscape in the past (deforestation, crops and use of plants in the deposit). The results show that the great spatial heterogeneity observed in the record is largely conditioned by taphonomical factors linked to terrigenous sedimentation in Sector A: subaerial conditions and soil erosion processes favoured the expansion of ferns in the area, and did not allow the development of coprophilous fungal organisms as observed in Sector D. However, it has been possible to identify some patterns linked to the incidence of human activity. Three structures appear associated with the use of fire, indicated by the accumulation of spores of carbonicolous and lignicolous fungi, and an accumulation of anthropic herbaceous taxa was identified to the Northeast of the sector in structure E263, indicating a possible area of storing and processing plants of socio-economic use. Finally, 14 new types of NPPs were described in Sector A. This new contribution to the understanding of the formation processes of the site and the use of space and plant resources by the first Neolithic societies in the north-eastern Iberian Peninsula demonstrates the validity of the spatial approach in archaeopalynology.
Equids played an important role in the development of communication in past societies, and were part of the
exchanges between populations. The multi-isotopic study (strontium, carbon and oxygen isotopes) conducted on
equid teeth from Bronze and Early Iron Age Can Roqueta suggests that animals originate from diverse locations
and their diet was carefully managed. The enriched oxygen and carbon isotopic ratios in equid teeth compared
with other taxa from the same site suggest that equids may have drunk from water troughs, thus creating a 13C
and 18O isotopic enrichment and partial covariance, similar to a “lake” effect. This is the most comprehensive
study on equid mobility in Iberia so far.
Presents a new approach to the problems of erosion and alluviation in relation to vegetation cover and its modifications by man, within which the significance of relations between geography and archaeology are implicit. -after Editor
Pollenanalytical and pedoanthracological data show that burning has been a constant means for man to clear areas necessary to his activities for at least five millenia. The changes induced by this practice are so far-reaching that modem ecological analysis cannot determine the real vegetal potentialities in western Mediterranean regions.
L'étude de la lagune actuelle de Canet et celle de son extension passée en direction de Saint-Cyprien offrent quelques repères palynologiques en relation avec de nouvelles datations au radiocarbone. La végétation, au Boréal, avec Pinus, Quercus et Corylus, contient tous les taxons arboréens et arbustifs méditerranéens, habituels en analyse pollinique ; la date 14C est de 8520 ± 120 B.P.
Pendant la période atlantique (date au radiocarbone : 7050 ± 80 B.P.), la série du Quercus suber colonise le Roussillon et l'effet de l'action de l’Homme commence.
De 4880 ± 80 B.P. à 4200 ± 90 B.P., les séries des Quercus à feuillage caduc augmentent. Aux environs de 4200 B.P., tandis que Abies régresse et que Fagus croit à sa place en montagne, les végétations de garrigues démarrent dans la plaine avec Quercus type ilex-coccifera, Cistus etc. Le paysage du Moyen âge (700 ± 70 B.P.) montre des indicateurs presque totalement anthropiques tels que Vitis, Secale, Juglans, Olea, Castanea., Platanus.