Exploring the role of plant–animal interactions in the long-term development of heritage landscapes in Europe

Abstract

Spanning from southern Europe to central and eastern Europe, open woodlands, such as forest-steppe and garrigue, and the grasslands within, constitute protected heritage landscapes considered hotspots for biodiversity, faced with threats from climate change and the disappearance of traditional farming and herding practices. Through a review of published case studies, we explore the biographies of the Eurasian agro-pastoral landscapes in eastern Europe, southern France, the Iberian Peninsula and the Italian and German Alpine forelands. Alongside depicting the natural features that raise our interest in these environments today, we search for anthropogenic agencies in the formation and maintenance of agro-sylvo-pastoral land use in these interconnected aspects: forest openness, biodiversity and animal husbandry. We focus especially on the impact on vegetation of domesticated animals since prehistoric times. Based on different kinds of complementary proxies from palaeoecology as well as bioarchaeology and geoarchaeology, we demonstrate that these environments are the result of a longue durée process at the interplay between natural and anthropogenic dynamics. This review highlights the importance of further understanding landscape dynamics through the lens of long-term developments of environments and of herding/farming practices, to help inform tangible cultural heritage and conservation programes for the protection of European landscape diversity.

This article is part of the theme issue ‘Unravelling domestication: multi-disciplinary perspectives on human and non-human relationships in the past, present and future’.

1. Introduction

The fabric of landscapes is shaped by physical forces such as hydrology, climate, topography and lithology, and determined by organisms in the biome, such as plants and animals. Meanwhile, human populations over time have increasingly altered and transformed landscapes [1,2], primarily for food production purposes through herding and farming of domesticated species. Prior to the introduction of farming into Europe, by the Mid-Holocene diverse forested environments had developed that varied in species composition as a result of geomorphology, geography and climate [3–7]. Likewise, alongside extensive woodlands, open habitats were present in relation to water courses as well as natural clearings that were maintained in part by wild animals [1,8,9]. The transformation of these Early-Mid Holocene environments over thousands of years via climatic change alongside human activity has led to the development of new ecological habitats, in what can be considered a continuous process. Present-day European agro-sylvo-pastoral landscapes are recognized as an important component of tangible and intangible cultural heritage and local identities (hereafter ‘heritage landscapes’), while representing significant areas of biodiversity from an ecological point of view [10–14]. These landscapes correspond to fragile ‘ecosystem complexes’ [14], such as those of the Mediterranean garrigue and Iberian dehesa/montado, the Eurasian forest-steppe, and the relict xerophytic calcareous grasslands in the Italian and German Alpine forelands (figure 1). Today, they are often threatened owing to the disappearance of the low impact non-intensive traditional practices that fostered them for millennia.

Figure 1.

The landscapes discussed in the text are displayed on the map of European ecological regions (http://www.eaa.europea.eu/). The legend focuses on vegetation components from the study regions only; full legend available online. The photos represent (a) garrigue in Languedoc, France (H. Soria, 2005); (b) dry grasslands in Baden-Württemberg, Germany (L. Brandtstätter, 2024); (c) dry calcareous grasslands in the Euganean Hills, Italy [15] (M. Dal Corso, 2024); (d) forest-steppe in central Ukraine (M. Dal Corso, 2016); (e) forest-steppe in Crimea (A. Salavert, 2011); (f) dehesa in Extremadura, Spain (A. Beltz, 2006).

Animals, namely herbivores both wild and domesticated, are being increasingly recognized as niche constructors [8,16–18]. However, the effects of animal husbandry on landscape transformation are largely understudied in the reconstructions of the palaeoecological and anthropogenic processes that since millennia have transformed the natural environment in temperate, continental and Mediterranean Europe. Traditional herding practices have been and still are pivotal in maintaining these important areas of biodiversity, while at the same time physical aspects of a particular region influence herding practices in terms of the choice of domesticated species and production strategy [19]. For example, there is reduced ability for woodland regeneration within areas once intensively grazed by domestic (cattle, goat) or wild animals [14]. This results in a semi-open landscape with shrubs and grasses, where younger tree growth is restricted to hard-to-reach areas. By contrast, animal trampling, e.g. by sheep herds, can create good conditions for tree seedlings but on a limited scale and only in cases of non-intensive (non-continuous, and/or seasonal) grazing [20]. Moreover, animals actively transform plant composition and distribution via zoochory and enrichment of soils with dung [21,22]. Therefore, besides climate and other physical factors, among anthropogenic activities, herding practices should be considered as having a significant impact on the evolution of European landscapes [12,18]. For this reason, we seek to understand the role of prehistoric animal husbandry in the development and maintenance of agro-sylvo-pastoral landscapes.

To deepen our understanding of landscape formation in the selected regions, we take the perspective of a longue durée and examine long-term changes in forest cover, biodiversity and herding practices, as key aspects characterizing agro-sylvo-pastoral land use. These three interconnected aspects allow (i) an investigation of forest cover, diversity and structure, i.e. species composition and the degree of canopy openness; (ii) tracking changes in biodiversity due to the creation of new habitats after anthropogenic disturbance; (iii) a reconstruction of land use within different types of forested or open environments offering a range of seasonal resources and under contrasting husbandry regimes. For instance, increase in botanical synanthropic species [23,24], as far as palaeo-records allow taxonomic identification, is known at least within traditional farming and husbandry. Such three aspects could be interlinked: for example, the collection of meadow resources for fodder could lead to the creation of selective clearings [25,26] while grazing/browsing within woodland could create open patches and plant species selection [27,28]. Changes in nutrient levels and trampling due to animal passage for seasonal movements or penning will cause the disturbance of plant communities, to the detriment of some plant species in favour of others.

Our second aim is to provide an overview of the methodological approaches for reconstruction of regional landscape development, which can inform and contribute to current habitat conservation actions. To explore the longue durée, researchers use different kinds of on-/off-site proxies that allow a (pre-)historic perspective on human–plant–animal interactions. This is not without challenges, and to assess the degree of anthropization of a given landscape via activities, such as herding, can be difficult. First, this is due to the difficulty of defining the ‘naturalness’ of a studied region i.e. an ecosystem shaped by natural factors alone [20,29]. Herbivory by wild animals (from large herbivores to beavers) shapes landscapes and in some cases has been proposed as a driver of ecological change, such as forest openness, prior to the advent of farming [16]. This obviously complicates teasing apart herbivory by wild or domesticated animals from small-scale herding systems, such as prehistoric ones. Secondly, the chronological and spatial resolution of on-/off-site bioarchaeological archives is often different, and therefore, to overcome this, multi-proxy perspectives are required. Thirdly, other practices may have favoured forest openings, namely crop cultivation and settlement. We will consider these challenges when comparing the landscape biographies attested in palaeoecological and archaeological archives from the selected regions (figure 1).

In our review, attention is given especially to the period between the Neolithic and the Iron Age (6th−1st mill. BCE), i.e. the arrival of the first farmers and herders until the establishment of complex and interconnected societies in late prehistory. Evidently later periods had a significant contribution to the development of such heritage landscapes as we know them today. However, we are here concerned in identifying the impact of early farming in the selected regions and with it characterizing early agro-sylvo-pastoral land use, particularly animal herding, which can be now approached with different research methods. Using a survey of published literature, we review palaeoenvironmental and archaeological studies of European regions that (figure 1). Via case studies, we will synthesize and correlate multi-proxy evidence to investigate the processes leading to the emergence of what resonates with today's heritage landscapes, as well as the socio-environmental and ecological outcomes within these landscapes that have resulted from the impact of herding animals. These case studies will allow us to highlight the gaps in the research and future directions, necessary to understand the dynamics of heritage landscapes while contributing to inform future conservation strategies.

2. Complementary materials and methods

Understanding the complex scenarios that have led to the creation of European landscape diversity in a long-term perspective requires a holistic approach that encompasses the natural sciences and humanities. Methods of investigation come from the fields of palaeoecology, palynology, soil sciences, genetics, geochemistry (biomarker and stable isotope analysis), and archaeological sciences, such as zooarchaeology, palaeo-ethnobotany (or archaeobotany), geoarchaeology, bioarchaeology, traceology, among others. In general, the most complete picture derives from a multi-disciplinary approach because of differential preservation of the materials and archives, and because of the spatial and temporal limits relative to each method. Moreover, by integrating different proxies from independent archives, it is possible to tackle complex research questions about resource management as well as distinguishing between human and climatic influences on changes in woodland cover.

The proxies to investigate the environmental and cultural history of a region can be found in both on- and off-site archives (figure 2). These archives can be considered complementary because they have different temporal and spatial scales and relate to complementary human activities [30,31]. Off-site archives can be exploited to uncover past landscape dynamics and land use from undisturbed, continuous, diachronic sequences (e.g. lake sediment cores, peat sequences from mires, soil sequences), allowing the reconstruction of long-term continuous/semi-continuous diachronic perspectives. By contrast, on-site archives (e.g. archaeological stratigraphy and materials, including coprolites, macro-faunal and -botanical remains) usually cover shorter temporal scales, although some archaeological sites cover thousand(s) of years, and relate to well defined cultural dynamics. Human selection and taphonomy mitigate the extent to which plant and faunal records accumulate on-site; however, these materials are used to assess the exploitation of plant/animal resources and, indirectly, characterize local environments. Environmental information in terms of forest composition and biodiversity gained from on-site archives, such as that recovered from the study of wood in waterlogged sites [32,33], can be verified by independent proxies from off-site ones. For example, on-site charcoal assemblages help to disentangle firewood and leafy-hay use (e.g. [34]), while off-site micro-/meso-/macro-charcoals allow the reconstruction of regional and local fire history (e.g. [35–37]). Moreover, vegetation history and the quantification of forest cover based on palynology vary from a (supra)regional to a local reconstruction, according to the geomorphology and catchment of the basin under study (e.g. [38,39]), and vegetation history or environmental rconstruction is usually associated, nowadays, with the recovery of spores of coprophilous fungi which provide evidence of pasturelands. Geoarchaeology also contributes to the study of the formation and evolution of anthropogenic features and landscapes through the analysis of both natural pedological and sedimentary deposits and archaeological sites (e.g. [40–42]). Furthermore, secondary analyses on off-/on-site records, such as stable isotope analysis, environmental and ancient DNA (eDNA and aDNA) and biomarker analysis provide additional information about animal husbandry and its relationship with local ecologies. For example, low stable carbon isotopic values from animal bone and teeth can indicate the use of woodland pasture and leafy-hay fodder; large-scale diachronic studies of single cultures can demonstrate changes in these practices relative to landscape openness [28,43]. In terms of herding practices and, indirectly, of grazing pressure, a particularly rich source of information are coprolites, fumier and dung layers from stables and animal penning areas, including caves and rock shelters, which can inform us about the use of the territory and, potentially, seasonal practices (e.g. [44–47]).

Figure 2.

A comparative illustration of the main proxies found in on-site (archaeological; shorter duration) and off-site (natural; longer duration) archives. Many proxies may be studied in both kinds of archives and different independent proxies can contribute to the study of landscape openness, biodiversity and herding practices in the past, ultimately leading to the reconstruction of landscape developments. Graphic: M. Dal Corso.

3. Towards a biography of European agro-sylvo-pastoral landscapes

(a). Western Mediterranean agro-sylvo-pastoral landscapes

The Mediterranean region presents a very diverse geography of mountains, valleys, inland and coastal environments, covered by woodlands and scrublands, under a climate characterized by dry and hot summers and mild and humid autumn–winters (dry/warm summer Mediterranean climate, CSa/CSb, Climate-Data.org; [48]). Within this macro-region, in river valleys and on plateaus in the western Mediterranean basin including the Iberian Peninsula, sclerophyllous and semi-deciduous woodlands characterize the landscape [49]. Within this ecoregion, agro-sylvo-pastoral landscapes, such as the dehesa in southern and central Spain and montado in Portugal (figure 1f), play a significant role in livestock rearing, while in the adjacent ecoregion of northeastern Spain and southern France Mediterranean forests [49], low shrubland known as garrigue can be found which constitutes another type of Mediterranean forest-steppe (figure 1a). The formation of Cistus, Halimium and Thymus garrigues developed by grazing and (natural/anthropogenic) firing of the Quercus rotundifolia woodland [50]. The garrigue, dehesa and montado are remarkable Mediterranean landscapes in terms of species composition, structure and ecology, in a long-term co-evolution with human cultures. At the same time, (micro)climate has played an important role in this region in shaping the vegetation mosaic, as seen during the Early and Middle Holocene with the example of the expansion and displacement of birch (Betula), which prefers humid conditions [50], or of beech (Fagus) expansions in the plains from refugia [51]. Bioarchaeological archives are of fundamental importance in understanding the chronological and cultural framework of these agro-sylvo-pastoral landscapes’ development (figure 3).

Figure 3.

Western Mediterranean: map of the sites mentioned in the text, with information about the proxies used in on- and off-site studies: (1) Gazel (France), (2) Taï (France), (3) Cazan-Le Clos du Moulin (France), (4) Abeurador (France), (5) Font-Juvénal (France), (6) Cova Colomera (Spain), (7) Lake Banyoles and La Draga (Spain). Map produced with ArcGIS Pro by R. M. Rossi (University of Padova), basemap sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, © World Wildlife Fund, Inc. and the GIS User Community. Graphic: M. Dal Corso.

Dehesa and montado landscapes of Iberia are classified as sclerophyllous pastoral woodland composed of cork oak trees (Quercus suber) and other species, such as evergreen oak (Quercus ilex), olive (Olea europaea), sweet chestnut (Castanea sativa), ash (Fraxinus spp.) and willow (Salix spp.), accordingto the soil wetness, interspersed with agricultural fields, olives and other fruit trees, and pastures. They support wildlife as well as livestock and crops, and forest products like cork, honey, mushrooms and wild game. Over the past century many dehesas and montados have been cleared to create monocultures. The species composition that makes up these mixed woodlands highlights how these biomes are dependent on climate, soil, topography and geology, and at the same time shaped by the intensity of land-use history and grazing seasonality. Dehesas and montados form an important part of the transhumance systems, used seasonally during winter and spring, on the migration routes between high mountain grasslands and the lowlands woodland pastures (cañadas in Spain). In the seasonality of Mediterranean wood-pasture usage, water availability is important because tree density is related to both ecohydrology and socio-economic factors. For example, in dehesas close to Seville, tree density was found to be low where rainfall measured above 650−700 mm, in comparison with areas where rainfall was greater than 650−700 mm and tree density was more controlled by socio-economic factors [52]. Moreover, the structure and species composition of these wood-pastures depends on the grazing species and the size of the herds [28,53,54] . Palynological studies in southwestern Spain covering from the Mid-Holocene until to 1900 CE [55] suggest that during the Iron Age, a more developed dehesa occurred that lasted throughout the Roman to Medieval periods.

Botanically speaking, the garrigue ecosystem in France is evergreen open scrub-pasture, rich in herbaceous and small woody plants, such as evergreen oak and juniper (Juniperus spp.), but also shrubby trees like box tree (Buxus sempervirens), rosemary (Salvia rosmarinus) and cistus (Cistus spp.) found on stony and poor-nutrient calcareous soils. Unfavourable microclimatic conditions given by a prolonged dry season, fires, but also animal trampling and grazing, are what enable the garrigue to maintain itself over the long term. Indeed, the garrigue is a state of the landscape within an ecological cycle [56]. Currently, in such an environment without human/domestic animal pressures, it has been shown that boxwood moor gradually evolves into wooded brush, followed by forest recolonization with pubescent oak [48].

In southern France, several analyses based on archaeological wood charcoal, like at L’Abeurador and Font-Juvénal [57] (figure 3), have shown the increase of evergreen oak together with box, to the detriment of deciduous oaks in Mediterranean limestone environments, from the end of the Neolithic (ca 3000−2500 BCE) onwards [57–60]. In the Rhone Valley, off-site sequences and on-site archaeological records have given a contradictory picture of the environment, depending on the proxies used. Phytolith analyses of dung indicate a dominance of grassland formations, and thus a widely open woodland landscape. By contrast, most charcoal samples indicate a deciduous oak forest in both on-site and off-site records. This dichotomy has been interpreted as evidence of an agro-sylvo-pastoral system with a physiognomy that can be close to the dehesa system. At the Middle Neolithic site of Cazan-Le Clos du Moulin, Provence, France (figure 3), the regular selection as fuel of the heliophilous shrub Arbutus unedo (strawberry tree) attests the existence and use of scrubland, possibly also for pasture [61]. In the garrigue, goat grazing and tree fodder are proposed to explain the replacement of the original deciduous oak forest by evergreen oak, which is more competitive in the case of anthropogenic disturbances [62]. Stable isotope analysis from caprine teeth from Taï and Gazel, Languedoc, France (figure 3), indicate the consumption of forest products in the winter, which may have been a deliberate strategy [58]. At Taï, a multiproxy analysis highlights the major role played by forest grazing, mainly by sheep/goats, in explaining the replacement of the original deciduous oak forest with dense evergreen coppice, especially in the Middle Neolithic [61].

In Catalunya, northwestern Iberia, an increase in maquis vegetation has been seen during the 5th millennium BCE related to animal grazing [63,64]. At La Draga, an Early Neolithic waterlogged site situated on Lake Banyoles (Catalonia, Spain) (figure 3) has well preserved on-site contexts [65,66] and off-site archives [67]. Palaeoenvironmental studies revealed that prior to the arrival of the first farmers in the 6th millennium BCE, dense forests predominated by broadleaf deciduous trees (deciduous Quercus, Corylus), riparian forests next to the settlement (Fraxinus, Salix, Ulmus, Alnus), and a slight signal of regional sclerophyllous forests (mainly Quercus ilex/coccifera) and Mediterranean maquis (Erica) occurred [67,68]. Forests were actively managed by the farmers for firewood and construction, with the selection of specific trees for different purposes [69], and fern spores and micro-charcoal in lacustrine deposits from ca 4000 cal BCE have been proposed as evidence of clearance of deciduous and riparian local woodlands for livestock grazing [68,70]. Concerning the use of forests for animal husbandry, stable isotopic research found depleted δ¹³C values in sheep teeth that were interpreted as a reflection of marsh plant consumption [71]. However, riparian forests are excellent sources of fodder [72,73] and potentially have carbon isotopic values similar to that of marsh plants [74].

The early emergence of agro-sylvo-pastoralism cannot be generalized to the entire western Mediterranean zone. Indeed, in some more humid areas such as at the Cova Colomera site in the pre-Pyrenees, Spain (figure 3), low intensity of human activities, particularly of pastoralism, is attested by anthracological data that report a dominance of deciduous oaks at least until the Bronze Age, ca 2000−1000 cal BCE [75]. Overall, studies have shown no synchronicity in the establishment of these forest-steppe environments in the western Mediterranean [76]. Therefore, given the geographical diversity of the region, more micro-regional studies with a multiproxy approach are required, as previously proposed in reviews concerning fire history [77] and land use [78].

(b). Open vegetation and dry grasslands in the German and Italian Alpine forelands

Northern Alpine forelands are part of the ecoregion of the western European broadleaf forests [49], where beech (Fagus) represents the main climax tree species. Beech primaeval woodland and mixed deciduous woodlands covered most of these landscapes apart from wet habitats. This region, with its young moraine landscape characterized by a temperate climate (Cfb, Climate-Data.org), is rich in lakes and peatlands of different sizes. Natural and anthropogenic fires have played an important role for the creation of forest openings. The lakes and peatlands of the region provide rich multi-proxy evidence on the interplay of environmental change and human activities [79–83]. Fire history can be reconstructed from micro-charcoals obtained from the palynology slides [84,85], charcoal in soil thin sections [86] or combining both micro- and macro-charcoals [35,37,87]. In general, the open vegetation in Central European landscapes, when not dependent on river courses and wetlands, is mostly derived from land use for human subsistence practices since the onset of the Holocene.

The Early Holocene sediment record from the palaeo‐wetland in the Ammer Valley (southwest Germany) provides a palaeoecological record [87] that tracks the evolution of this landscape (figure 4a). A climatically driven transition from a river-dominated landscape towards a wetland with open stagnant waters occurred at 10 600−9500 cal BP, making the region attractive to hunter–gatherers. Mesolithic communities contributed to shaping the environment by using fire as a tool to expand open areas, as testified after 9500 cal BP by frequent low‐intensity fires and vegetation disturbance. These openings were important for their subsistence strategies because young edible undergrowth attracted wild herbivores, as well as for pioneer light-demanding vegetation including nutrient‐rich hazels [81,88]. Using leafy-hay as winter fodder and cattle pasturing in the forests were practised, enhancing animal husbandry in forested ecosystems, as discovered through the study of faunal stable isotope values (δ¹³C and δ¹⁸O; compound-specific stable isotopic analysis δ¹⁵N-amino acids and δ¹³C-dairy fats) across Central Europe during the 6th millennium BCE [28,89]. A second phase related with forest openings from the 5th millennium BCE corresponds to advanced stages of Neolithization. From the Middle Neolithic onwards and especially during the Late Neolithic fire was applied to deforested areas [90,91], or previously burned fields were manured by using them for pasture. Moreover, numerous palynological records in the region document from 4900 BC the onset of elm decline as a result of livestock and woodland management practices [81]. There is further evidence of a strong decrease of beech and final elm decline in many pollen records around Lake Constance at Böhringer See, Hornstaad, Mindelsee, Mainau and Steiβlinger (see figure 4a), during the Late Neolithic (Pfyn culture, 4300−3500 cal BCE), suggesting deforestation and heavy coppicing [81]. Evidence for permanent open vegetation as in earlier (glacial) and later periods is missing. However, as the forest became less dense, understorey vegetation was encouraged (indicated by the increase of hazel), allowing greater access to rich grazing for domesticated animals, as visible even in direct studies of plant remains in sheep/goat dung from an archaeological context [92]. Subsequently, in the Late to Final Neolithic (3400−2900 BCE), agricultural fields became permanent and the importance of livestock farming increased [83,89]. Weeds new for the region, such as corn cockle (Agrostemma githago), field mantle (Aphanes arvensis), sand poppy (Papaver argemone), French cuckoo flower (Silene gallica), but also species that today grow in meadows and pastures, such as grass aster (Stellaria graminea) and ribwort plantain (Plantago lanceolata), have been interpreted as evidence of this intensified land use. Such segetal plants could grow on fields that during short fallow periods were grazed [93]. The palynological records show the increased importance of pioneer trees (mostly birch and hazel) in the vegetation as well as charred particles, suggesting possible low coppiced forests with an important role of grazing and use of fire.

Figure 4.

German and Italian Alpine forelands: map of the sites mentioned in the text, with information about the proxies used in on- and off-site studies for (a) southern Germany: (1) Hornstaad/Untersee, (2) Mainau, (3) Mindelsee, (4) Steisslinger See, (5) Bad Waldsee, (6) Zeller See, (7) Ammer Valley—UJ15, (8) Ammer Valley—X039, (9) Aalkistensee, (10) Heuneburg. (b) Northern Italy: (1) Bergamo, (2) Mincio River sequence FOR 6, (3) Mincio River sequence BAGN 1, 2, (4) Bande di Cavriana, (5) Castellaro Lagusello, (6) Lucone D, (7) Lavagnone, (8) Santa Rosa di Poviglio, (9) Fondo Paviani, (10) Oppeano 4D, (11) La Muraiola di Povegliano Veronese. Map produced with ArcGIS Pro by R. M. Rossi (University of Padova), basemap sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, © World Wildlife Fund, Inc. and the GIS User Community. Graphic: M. Dal Corso.

After the Neolithic, at the onset of the Bronze Age (ca 2200 BCE) and especially during the Middle Bronze Age (1600−1200 BCE), new land use patterns emerged that only rarely involved fire [94]. In the Late Bronze Age (1200−800 BCE), soil erosion caused by deforestation and extensive ard cultivation led to the development of shallow topsoil on slopes and hilltops. These new habitats were favourable to plants resistant to drought, and indeed from the Late Bronze Age onwards members of the Caucalidion weed cohort, i.e. heliophilous herbs which are weak competitors compared with other crop weeds, increased in the archaeobotanical and palynological assemblages in the northern Alpine foreland [93]. The members of this cohort benefit from soil and vegetation disturbance by agriculture and grazing; many grow today in dry grasslands on disturbed sunny slopes. The 1st millennium BCE can be described as one of the first periods in Central European history in which human economic practices caused pronounced and, above all, large-scale changes to the environment and landscape throughout most of the region. For example, during the onset of the Iron Age from about 800 BC onwards, a clear phase of reduction in forest cover can be observed. This first strong and permanent deforestation, caused by logging, agriculture and forest pasture, emerged from the eighth century to the fifth century BCE in pollen archives at Bad Waldsee in Upper Swabia [95], at Aalkistensee in the Kraichgau [91] and at Huzenbacher See in the northern Black Forest [96] (figure 4a). In Zeller See, for instance, the deforestation was followed by phases of increase in light-demanding trees, such as birch (Betula spp.) and hazel (Corylus avellana), in grasses and in anthropogenic indicators: plants that benefit from arable farming and opening of the landscape [97]. In many areas, the forests had a more mixed and open character [98]. The increase in grazing indicators such as ribwort (Plantago lanceolata) is also clearly pronounced; thus pastures and meadows expanded alongside arable land. Forest and pasture were probably neither spatially nor functionally separated [99]. Grassland is essential for larger-scale animal husbandry and, at least since the Late Bronze Age, towards the end of the 2nd millenium BCE, open spaces played a significant role in human subsistence in the form of field-grass economy [99], as evident also from the archaeobotanical record from the hillfort of Heuneburg [100] (figure 4a).

South of the Alps, the ecoregion of the Po Valley mixed forests [49] stretches across northern Italy following west–east the hydrographic basin of the main Italian river, the Po River, and its several tributaries, along with other rivers, until the Adriatic coast. The floodplain is between the foothills of the southern Alps in the north and the northern Apennines in the south (figure 4b). The climate is classified as humid subtropical (Cfa, Climate-Data.org) and it is transitional: cooler in the north, with warm summers and persistent air humidity, and Mediterranean in the south and in specific micro-regions such as around Lake Garda and in the Euganean Hills. Annual rainfall ranges from 500 to 1000 mm. Nowadays this region is one of the most industrialized in Europe, covered by wide agricultural fields, artificial urban and industrial areas and intensively used traffic-ways. The few surviving natural environments consist of restricted, protected riparian woodlands and wetlands, which are important for wildlife, birds especially [101,102].

Before intensified human impact, the Po Valley was covered by mesophile mixed deciduous woodlands, which changed composition during the Holocene, following climatic and cultural dynamics (for a synthesis about the central–northern part of the Po Valley, see [38]; for the southern Po Valley, see [103]). The climax vegetation of the region has been recognized in the deciduous oak–hornbeam association (Querceto-Carpinetum boreoitalicum [104], with Quercus robur and Carpinus betulus). According to palynological and anthracological analyses, this mixed deciduous forest spread during the Mid-Holocene, when less resilient tree species, such as silver fir (Abies alba) and beech, previously growing in the hills and on the upper plain, were affected by anthropogenic fires and forest disturbance in the Neolithic and Copper Age, e.g. in the lower Mincio River [105], at Castellaro Lagusello [106] and Bande di Cavriana [107] (figure 4b). Mixed deciduous oak woodlands of common oak, hornbeam, maple (Acer), lime (Tilia), field elm (Ulmus) and southern flowering ash (Fraxinus) covered upland areas of the drained Pleistocene fluvial terraces, while riparian forests with alder (Alnus) and willows (Salix), peat bogs and swamps could be found in the periodically inundated valleys of the floodplain. More resilient to logging, coppicing and forest pastures, mixed deciduous woodlands were widely used since the Early Bronze Age by the settlers of the numerous pile-dwellings present along small water basins in the southern Alpine forelands (e.g. [106–109]). In the Middle Bronze Age (1650−1450 cal BCE [110]), with the capillary population of the Po Valley by farmers and herders of the ‘Palafitticolo-Terramaricola Culture’, a first phase of pronounced human impact contributed to change the aspect of the plain. Forest clearance, attested by peaks in micro-charcoals at the onset of villages, decrease of arboreal pollen, high diversity in heliophilous plants and strong increase in anthropogenic pollen indicators of arable land and grasslands (e.g. at Santa Rosa di Poviglio [111], Fondo Paviani [106,112]; figure 4b) correspond to the establishment of a new type of settlements, surrounded by enclosures (palisades, ramparts, moats), called ‘terramara’ and found in the floodplain until the Late Bronze Age (1150 cal BCE [110–112]).

In domestic sites, where stabling layers rich in herbivore dung and litter have been identified by soil micromorphology and gas chromatography–mass spectrometry (GC-MS) biomarker analysis (e.g. Oppeano [113] and La Muraiola di Povegliano Veronese [114]), on-going investigation of botanical micro- and macro-remains coupled with faunal isotopic analysis are enabling us to define animal husbandry practices based on a variety of plant resources from floodplain woodlands to humid and dry grasslands [115–117]. River landscapes, with meandering channels and periodically flooded areas, allowed seasonally available open areas on wet substrate where grasses and sedges grew year-round. With the Bronze Age, drained upland territories occupied by woodland became suitable for agriculture and pastures too, as suggested by increasing evidence of dry grassland, favoured by grazing pressure and attested in the upper Po Valley and hills south of Lake Garda by palynological records [21,106,109,116,117], and sometimes also by carpological remains, e.g. at the waterlogged sites of Lucone D, Lavagnone [108,118] and Oppeano 4D [115] (figure 4b). To this group belong sunrose (Helianthemum sp.), small scabious (Scabiosa columbaria), burnet (Sanguisorba minor) and white laceflower (Orlaya grandiflora), among others. Salt-tolerant plants from dunes, such as sea lavender (Limonium sp.), can surprisingly be found in the inner part of the plain [106], likely testifying to natural open environments in sandy alluvial substrates that are completely lost in present times. Sand dunes were known until the last century in the upper plain close to Verona [119]. Nowadays almost disappeared, residual dry grasslands used in historical times as pastures/meadows called ‘magredi’ [120,121] and mixed deciduous forests dominated by oaks and hornbeams can be found in the northeastern upper plains and prealpine hills [122]. The first suggestion until now of haymaking on meadows in the region occurs in the Final Bronze Age at Bergamo [21], although this is sustained by plant indicators that have been attested also in the Middle Bronze Age in Oppeano 4D [115,116] (figure 4b).

The Po Valley continued to be transformed by agriculture, with drainage channels and land parcellation since Roman times, and pastures in areas of both woodlands (especially for pig husbandry) and grasslands. Wetlands provided useful plant material for matting, roofing and other everyday objects until the last century, when land reclamation and new production strategies caused the almost total loss of interest in and disappearance of these kinds of environments [101]. The long landscape history of floodplains is difficult to study for the lack of undisturbed, continuous, off-site archives, but the several ‘stratigraphic windows’ associated with archaeological sites provide insightful records for the reconstructions of human–environmental interactions and landscape development.

(c). The East European forest-steppe

The Eurasian forest-steppe is a mosaic landscape, where the potential natural vegetation is composed of extensive mixed deciduous woodland patches alternating with grasslands. This zone occupies a 3870 km² area, elongated east to west from the Altaï Mountains to the Carpathian foothills, on contrasting topographical units like hills, plains, mountains and plateaus. Here we focus on its western fringe, the East European forest-steppe, which is considered a climate-sensitive transition biome between the Central European mixed deciduous forests in the northwest and the Pontic steppe in the southeast (figure 1d,e). The climate today is mostly humid continental (Dfb), with hot summers and cold wet winters (Climate-Data.org), and as such not impeding tree growth. Climate and mean annual precipitation are important factors in the distribution of forested areas within the forest-steppe, together with edaphic and topographic conditions [8,123–125]. The area's biogeography is highly dependent on natural conditions but also on long-lasting human activities [126–128]. For this reason, the degree of naturalness of such a mosaic landscape and, more precisely, the effects of anthropogenic activities on the ratio of wooded versus treeless areas have been under debate. According to Erdős et al. [124], ‘grasslands of Eurasian forest-steppe sometimes [are] misinterpreted as deforested or otherwise degraded vegetation’. From an ecological point of view, steppe patches within the East European forest-steppe are rare biodiversity hotspots [127,129,130] in a region that has been severely damaged by crop monocultures at the hand of multinational corporations (42% of the land cover is devoted to cultivation, http://www.oneearth.org/ecoregions/east-european-forest-steppe), and that is listed among the ‘nature imperiled’ areas of the world [49]. However, besides modern agriculture, other threats for grasslands come from invasive species and forest growth, especially along valleys where gallery forests expand towards plateaus (figure 1d). Conservation programmes tend to consider the active role played by traditional farming and herding practices, including the action of grazers [123,124] and of controlled fires [130], in the maintenance of such environments. Questions arise then in terms of development and biocultural relations of this species-rich transitional biome according to palaeoecological and bio- and geo-archaeological studies.

Prior to the Neolithic, in the East European forest-steppe openings in forest cover existing owing to control of forest growth by the action of wild herbivores (i.e. natural grasslands [8]) and seasonal fires, as seen for instance in the palaeoecological studies at Lake Stiucii, Romania [127], at Lake Durankulak, Bulgaria [131] and of fen profiles Junashkiv and Pukiv, Ukraine [132] (figure 3). Several proxies within palynological and micro-charcoal studies from a few diachronic off-site sequences provide evidence of a persistent canopy openness, varying from semi-open to open forest-steppe, throughout the Holocene [85,125,132,133]. This is attested, in palynological studies, by light-demanding tree species, arboreal and non-arboreal indicators of open canopy, and micro-charcoal records. Furthermore, in these studies, biodiversity patterns seem to reflect refugial dynamics occurring since the Last Glacial period in this transitional biome [132]. At Melnichna-Krucha, Ukraine (figure 5), on-site prehistoric carpological, anthracological and phytolith records revealed that Late Mesolithic people relied on wild resources from mixed ash and oak deciduous woods and wetlands, indicating a patchy forest cover [134]. Starting with the Early Neolithic, the same archaeobotanical proxies showed that open environments in the forest-steppe at Kamiane-Zavallia, Ukraine (figure 5), were preferred by human groups, who enlarged them through prolonged farming/herding activities [135]. The subsequent agropastoral economies also favoured openness and reduction of woodlands in the immediate settlement surroundings, for example at Kovacevo, Balgarchevo, Dzhulyunitsa and Galabnik, Bulgaria [136], at Nicolaevca, Moldova [135,137], and at other sites in the Balkans [138], a trend confirmed also by enhanced anecic earthworms’ activity leading to Chernozem formation [42] (figure 5). The use of fire against steppe vegetation, confirmed by phytoliths [139], has been attested by charred awns of feather-grass (Stipa sp.) in many Neolithic and Chalcolithic sites [15,134,135,140,141]. Where a diachronic view is available, it has been suggested also that changes in the economy between farming and pastoral regimes were influenced by climate, where more humid conditions supported sedentism and cultivation, as indicated by the palaeoecological study at Omelchenki, Ukraine [125] (figure 5). The emergence of extremely large flat ‘mega-sites’ (4150−3950 BCE) with designed layout showed cooperative intention as well as the appeal of natural forest openings to farmers/herders of the Cucuteni–Trypillia Culture, capable of a complex subsistence economy [15,137,142].

Figure 5.

East-European forest-steppe: map of the sites mentioned in the text, with information about the proxies used in on- and off-site studies: (1) Kovacevo (Bulgaria), (2) Galabnik (Bulgaria), (3) Balgarchevo (Bulgaria), (4) Dzhulyunitsa (Bulgaria), (5) Durankulak (Bulgaria), (6) Lake Oltina (Romania), (7) Lake Stiucii (Romania), (8) Nicolaevca (Moldova), (9) Melnychna-Krucha (Ukraine), (10) Kamyane-Zavallia (Ukraine), (11) Maidanetske (Ukraine), (12) Omelchenki (Ukraine), (13) Yunashkiv (Ukraine), (14) Pukiv (Ukraine), (15) Ksizovo-1 (Russia). Map produced with ArcGIS Pro by R. M. Rossi (University of Padova), basemap sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, © World Wildlife Fund, Inc. and the GIS User Community. Graphic: M. Dal Corso.

Animal grazing has been investigated in relation to the maintenance of grassland in the East European forest-steppe area, via on-site investigations that combined multi-stable isotope analysis with bio- and geoarchaeology. At the Trypillia mega-site of Maidanetske, Ukraine, stable isotope analysis attested manuring of crops and a differentiated diet for domestic animals, some of which were fed with nutrient-rich fodder (crop by-products) and others grazed in extensive pastures, thus contributing to forest openness [137,142] (figure 5). Another multi-isotope study on faunal remains was carried out at the Middle Bronze Age (2400−2100 cal BCE) site of Ksizovo-1, western Russia (figure 5). Results indicated possible seasonal mobility of humans and their herds within a limited region and suggested that such small-scale movements had a very local anthropogenic impact on the forest-steppe landscape [143]. A different kind of evidence of husbandry comes from coprophilous fungal spores and pastoral pollen indicators, which at Lake Oltina, Romania, increased towards the end of the 1st millenium BCE, in the Iron Age [85] (figure 5).

In general, despite the heterogeneity of datasets and resolutions that we have for this large region, the different records align about the longevity of natural and semi-natural grasslands in the East European forest-steppe, which is likely responsible for its exceptional biodiversity [127,144]. The most mentioned elements of disturbance for forest growth at climatically favourable conditions are natural fires and, since the Neolithic, anthropogenic ‘activities’ that include intentional fires, cultivation and grazing/foddering. With few exceptions, the role of wild herbivores and domesticated animal husbandry remains unexplored within long-term palaeoecological dynamics in the East Eurasian forest-steppe.

4. Concluding remarks and future perspectives

Woodland pastures and secondary grasslands are important habitats to explore the role that animal husbandry has played in shaping European landscapes. In Europe, from Scandinavia to the Mediterranean, there has been a long tradition of woodland pastures forming an important part of cultural heritage, particularly in southern and eastern Europe—for example, the mountain summer pastures that extend into montane woodlands, pastoral woodlands and scrublands in parts of eastern Europe, the Mediterranean and the Balkans [14,62,138,145]. However, changes in farming systems, as well as market demand, mean they are fast becoming a relic of past extensive subsistence strategies. Moreover, pasturing in woodlands was banned in regions of central and northern Europe owing to shortage of timber, growing populations and industry [14]. Modern research has shown how in some regions these pastures are highly sustainable considering increasing global temperatures (for example the Iberian dehesa/montado), while in others they are more sensitive to drought and anthropogenic pressures (for example, the East European forest-steppe,).

In our review, we focused on the early farming communities, examining via survey of published literature changes in forest cover, biodiversity and herding practices, key aspects characterizing agro-sylvo-pastoral land use. This allowed us to observe (i) reductions in forest cover and changes in forest structure; (ii) increase in biodiversity due to the creation of new habitats after grazing and mowing; and (iii) the significance of animal herding in prehistoric subsistence economies and the connected exploitation of a wide range of plant resources, especially from woodlands, and according to local environments. It is evident that in our case-study regions there was an increase in habitat diversity after the establishment of herding strategies. These habitats included patchy, open woodlands and scrublands, or dry grasslands. For example, we see in pollen from lakes, archaeological deposits and especially herbivore dung, evidence of plants growing in dry grasslands in the Bronze Age of southern and northern Alpine forelands as openings expanded within the woodlands or riverine landscape. The synthesis of evidence from proxies from on-site and off-site archives presented here indicates that domesticated animals played an important role in opening up forested landscapes, probably both directly and indirectly. In some areas this was significant, for example in southern France, where charcoal analysis showed shrubland increased in the Neolithic owing to browsing, at the expense of mixed-deciduous oak woodlands previously attested. Agricultural activities increased in intensity where animals may have played an important role in providing manure, and via routing and tillage allowed communities to expand to heavy soils. It is clear that agro-sylvo-pastoral landscape evolution derived from traditional farming (e.g. through the use of controlled fires) and herding (e.g. as a result of grazing/browsing and shredding) has encouraged biodiversity, with the establishment of shrublands and secondary grasslands [8,9,146,147]. However, our understanding of the modality of herding practices, in terms of, e.g. seasonal movements, foddering, housing and herd size, is still patchy. While stable isotope studies prove successful in providing information about diet [28,143,148] and mobility, more work is needed especially related to herd demographics, which is completely understudied, and the association with complementary palaeobotanical and geoarchaeological data. What we observed for late prehistoric times should be addressed in the future also for historical times since they too contributed to the creation of the palimpsest landscapes derived from agro-sylvo-pastoral land use. In historical periods, bioarchaeological sources are often underestimated compared with the attention given to written sources, although their combination could lead to a deeper understanding of herding practices and of their influence on a given environment, i.e. to the ecological response and sustainability of practices and their cultural significance.

The long-scale taming of European landscapes could be considered within the domestication framework. Landscape domestication has been proposed where the actions of human societies, such as cultural practices and decisions, have physically changed landscape ecology, biodiversity and openness, thus leading to a landscape that is potentially more productive [149,150]. This definition in the past has been related to the manipulation of plant ecologies by humans. The degree or intensity of anthropization can vary from none, i.e. pristine/natural environment; to low-level, where plants (and animals) may be unconsciously promoted via small-scale clearance; to managed, where plants are encouraged by intensive clearance; to finally cultivation of a restricted group of plants creating an environment with little similarity to neighbouring ecosystems [151]. These landscapes would not have developed or been maintained without human and domesticated animals’ action. On the other hand, when considering domestication being a process that leads to a population that is biologically different from its ancestor, it is harder to sustain the definition of ‘domesticated landscapes’. The question is rather theoretical, as many of the definitions of domestication [152] consider the exigences of one species (such as humans) on another (be it a plant or an animal species). Can a landscape be domesticated? The landscapes we present here are ‘ecosystem complexes’ [14], which, in addition to ecological processes, are maintained by human action, including animal herding. At present, we do not fully understand the long-term impact, and the (pace of) reversibility, of these actions on wild plant/animal populations; perhaps the application in the future of genetic studies to wild species from palaeo-archives would nurture a cross-disciplinary dialogue between scientists on the concept of domesticated landscapes.

Beyond this discussion, our review, although not exhaustive, demonstrates the increase in multidisciplinary studies, employing independent proxies. However, in spite of this our state of knowledge remains patchy and this is in part the result of research traditions within a region (figures 3–5). It is key to consolidate information from off-site and on-site archives to create a cohesive narrative of landscape dynamics, but it is often challenging owing to different chronological resolution of on-/off-sites. The focus and terminology in use differ also among disciplines, which requires consideration, and this is clear from our use of ‘biodiversity’ as increase of species although the level of identification in palaeo-archives is not equal to that of modern biology. The multi-proxy studies demonstrate that considering a maximum of natural and archaeological archives can overcome the individual limitations of each discipline. Especially, the combination of data from faunal and botanical records, essential in the reconstruction of human impact by the first agro-pastoralists, can still be improved by merged research lines and a more open dialogue. Moreover, this review demonstrates the long-term agro-sylvo-pastoral character of some heritage landscapes and the role of husbandry in shaping these environments. It is very difficult to consider pastoral practices in isolation from other human activities, such as farming, when it comes to understanding the creation and maintenance of these iconic environments over time. However, the impact of animal husbandry practices on vegetation and soil is often underestimated in models that include reconstructions of past landscapes.

Finally, for conservation strategies against the loss of biodiversity the need to preserve, protect and encourage certain traditional production strategies is clear, given the long-term history of landscapes linked to both ecological and cultural actions [153,154]. These strategies differ by region, but in all cases, politicians and conservationists should keep in mind that it is a long-term development that combines human activities and ecological factors that has led to these heritage landscapes. In the last decades, conservation efforts have focused on European woodlands as they are considered primaeval forests. However, human–plant–animal interactions have shaped the environments for millennia [155], resulting in a diversity of European landscapes that form an important part of cultural identities tightly connected to alterations due to human intervention. In stark contrast to today’s monoculture farmscapes [156, pp. 63−66], traditional farming practices are considered necessary to maintain the significant heritage areas represented by agro-sylvo-pastoral landscapes [14] since complete land abandonment would lead to reforestation and loss of habitats and biodiversity. A present challenge concerns the implementation of sustainability and renewable resources, while reducing the impact of our production systems and lifestyles. Future research should focus on the uses of woodlands, together with other environments such as wetlands and grasslands, not only seen as pristine natural areas and biodiversity hotspots, but also conceived as a mosaic of environments that have long been targeted by human activities.

Ethics

This work did not require ethical approval from a human subject or animal welfare committee.

Data accessibility

This article has no additional data.

Declaration of AI use

We have not used AI-assisted technologies in creating this article.

Authors’ contributions

M.D.C.: conceptualization, data curation, formal analysis, funding acquisition, investigation, methodology, project administration, resources, writing—original draft, writing—review and editing; A.S.: conceptualization, investigation, validation, writing—original draft, writing—review and editing; E.M.-W.: investigation, validation, writing—original draft, writing—review and editing; R.E.G.: conceptualization, funding acquisition, investigation, validation, writing—original draft, writing—review and editing.

All authors gave final approval for publication and agreed to be held accountable for the work performed herein.

Conflict of interest declaration

We declare we have no competing interests.

Funding

This paper is the outcome of a meeting about ‘Coevolution of plants and animals during domestication’, funded by the Prehistoric Archaeology thinktank of ICArEHB (The Interdisciplinary Center for Archaeology and Evolution of Human Behaviour) funded by the Portuguese Foundation for Science and Technology (FCT) under programme UIDP/04211/2020 (PIs: R.E.G., M.D.C., Hugo R. Oliveira). M.D.C.’s work contributes to the European Research Council (ERC)-funded CoG project GEODAP, ‘GEOarchaeology of DAily Practices: extracting Bronze age lifeways from the domestic stratigraphic record’, no. 101001839.