The Last Days of a Mediterranean Wet Landscape:
© Andrea Luca Balbo
Paper Presented at the Forum UNESCO University and
Revised: July 2006
The Slavonic word polje literally translates into field or plane. In karstic geomorphology it indicates a tectono-karstic depression typically found in Dalmatia and often occupied by karstic lakes (Jennings, 1971, Jennings, 1985, O'Sullivan, 2004). As part of the wetland-reclamation policy promoted by Arrigo Serpieri under the Fascist regime, in 1932 the Italian government achieved the drying of Lago d'Arsa (Polje Čepić), the only karstic lake of Istria Peninsula, Croatia. Lago d'Arsa had been the largest natural basin of freshwater in the region. By draining the lake, this reclamation project was meant to bring new arable land and increase the overall regional agricultural production. As a matter of fact, since the desiccation of the lake, and because of the highly permeable karstic geological background, the lack of freshwater has been a recurrent issue in dry summers. Not even the construction of a dam and the creation of an artificial basin upstream in the 1960s were sufficient to overcome the increased agricultural need for freshwater, and the large new farms built on the polje floor were soon abandoned.
After briefly presenting the morphological characteristics of poljes and the origins of Polje Čepić, I report two contrasting views on the lake from the period of its reclamation. I then explore how the drying of the lake affected the way of living, the knowledge, and the culture of its people. Drawing from collected geoarchaeological (archaeological and palaeoenvironmental) evidence I show how a wet landscape had characterized the area and influenced its people for millennia, leading to specific cultural and land-use adaptations previous to its extinction. I suggest that the lowering of the water table is threatening the rich cultural and environmental heritage preserved within Mediterranean wet landscapes, preventing us from understanding the past of these landscapes and their people. Presently, a gas pipeline is being constructed through the polje. It is suggested that the development of such projects should involve the financing of scientific research in culturally sensitive regions. I finish by shortly assessing the potential of the geoarchaeological approach to cultural landscapes. Such an approach can inform on the processes underlying the development of peculiar adaptive strategies, as well as help managing the material and immaterial heritage including cultural identity, archaeological and environmental remains in rapidly changing environments.
The drainage of wetlands as a form of reclamation of new land for agriculture has been practiced since Protohistorical times, by Etruscans, Greeks and Romans (Smith, 1976). Among the reasons for drying wetlands is that a lowered water table allows for the development of deeper and drier soils, which warm up more quickly in spring and allow for an earlier plantation of crops. The downside of wetland draining is that the rich organic topsoil peat can be lost rapidly after drainage as well as the biodiversity usually associated to wetland wildlife habitats (Goudie, 1993, Goudie & Viles, 1997). One of the characteristics of land management in Italy, under the Fascist regime, at the beginning of the 20thcentury, was the reclamation of wetlands through systematic ditching and drying. The development of a strong agricultural policy through wetland reclamation projects (bonifiche from the Latin word bonus) was a priority. Istria was one of many regions around the Mediterranean in which the effects of such policy could be felt (Novello, 2003).
With this paper I will briefly describe the polje, a typical but underrepresented feature of the Mediterranean region, and its outstanding value as a karstic wetland and a cultural landscape (Fowler, 2004). The case study presented is that of Polje Cepic in Istria, Croatia, where a geoarchaeological project has recently taken place. After presenting two contrasting views of Polje Cepic from the late 1920s, I will discuss how the occurrence of radical changes in Mediterranean wet landscapes can affect their cultural identity and heritage. Considering a long-term time scale I will try to show the centrality of these wet landscapes in the Mediterranean karst. Based on historical and archaeological evidence, I will propose a view stressing the necessity for past polje settlers to elaborate mosaic land-use strategies. I will discuss the viability of such strategies in these environments, as an alternative to large engineering interventions. Supported by the first results of the geoarchaeological project ongoing in Polje Cepic, I will argue for the effectiveness of geoarchaeology in exploring the potential of poljes as containers of endangered cultural, archaeological and environmental heritage (Brown, 1997). As a conclusion I will place the geoarchaeological approach to cultural landscape in perspective with present-day management planning and sustainability of karstic regions.
CONTRASTING VIEWS ON THE DRYING OF ARSA LAKE
Poljes often occur where a limestone geological background is combined with orogenetic activity. It is likely that, following deglaciation (about 15,000 years ago) lakes occupied most of the poljes along the eastern Adriatic coast and other Mediterranean regions. Polje lakes are often shallow, with maximum depths of about ten meters, and are characterised by their hydrological variability, due to the geological background and to their sensitivity to seasonal and climatic changes (Jennings, 1971, Jennings, 1985). In spite of their variability poljes became attractive to many forms of life in a highly permeable environment where most of the water ran underground.
Polje Cepic is situated in the eastern-central part of the Istrian peninsula, at the northernmost tip of the Adriatic Sea. Polje Cepic is today an alluvial plain, located 24 to 27 m asl and about 5 km from the coastline. The polje is situated on an elongated depression developed on the western side of a structurally complex anticline (Mihljevic, 1998). The polje is surrounded by terrigenous Eocene bedrock (flysch), also constituting its basement (Sikic & Polsak, 1973). These flysch deposits form a low relief landscape on the eastern and northern parts of the polje, characterised by a network of shallow river incisions. To the east, the polje boundary is represented by the western flank of a north-south trending anticline, characterised by thrust structure of Cretaceous carbonates (Herak, 1991). This flank forms the steep slopes of the Ucka Mountains incised with a series of deep gullies. Most soils within the polje catchment developed both on terrigenous rocks of the Flysch zone and on the carbonates of the Ucka/Cicarija and Central Istria zones (Durn, 2003, Roglic, 1950, Skoric et al., 1987).
Poljes have attracted the attention of geologists, hydrologists, and engineers, who tried to understand their origins and functions, and eventually transformed them, in an attempt to improve the life of local settlers. It is only more recently that some attention has been paid to them by archaeologists, anthropologists and environmentalists. Many of these shallow lakes have dried up during the Holocene, especially due to the continuous accumulation of sediments. Polje Cepic was covered in water until 1932, when its reclamation was achieved by the Italian government, in order to introduce large-scale monoculture in the region.
The sustainers of the reclamation and the drying of the lake
Before 1932, and back to the 16th century, most maps picturing Istria showed the presence of a shallow lake within Polje Cepic (Lago & Rossit, 1981, Parenzan, 1928). In early 20th century Italy, Arrigo Serpieri was the main promoter and legislator of the so-called bonifica integrate (full reclamation) (Marasti, 2001, Serpieri, 1935, Tassinari, 1939). Shallow lakes, coastal lagoons, marshes, estuaries and all sorts of wetlands were being managed and dried all over the Italian peninsula and the colonies. Among other regions, major projects were being carried out in Sardinia (Angioni, 2004), Latium (Stabile, 2002) and Abruzzo (Giraudi, 1997). Issues related to land reclamation and its impact on local people and landscape were such a sensitive matter that the drying of Fucino Lake became the subject of the novel Fontamara (Silone, 1967). The draining of the lake occupying Polje Cepic was probably the most impressive infrastructure achieved in Istria under the Italian administration. The reclamation of the lake followed a succession of dry summers. In 1927 the Podesta of Albona (Labin), Conte Lazzarini ordered that each animal and man able to work should spend four days per year cleaning all ponds and lakes in the jurisdiction of Albona, to be used as storage for rain water (Lazzarini, 1927b). In 1930 the urge for freshwater became even more severe and Lazzarini ordered that water from the ponds should have been restricted to domestic use (Lazzarini, 1930). It was in this period that Lazzarini begun his campaign to obtain from the central government in Rome concession and support for the drying of Lake Arsa. He founded the Consorzio delta Bonifica dell'Arsa (Consortium for the reclamation of Arsa), while Prefetto (Prefectum) Mori was named chief of the reclamation of Arsa (Miglia, 1994). The drainage and the reclamation of the lake were promoted through strong propaganda, picturing the lake as a sort of malarial wasteland (De Franceschi, 1929, Lazzarini, 1927a). Eventually, Lake Arsa was dried-up through the construction of a four kilometer long, three meter wide underground channel conducting the water of the lake into Plomin Bay and the Adriatic Sea. After the opening of the tunnel, it took seven days to empty the large surface of the polje from which tons of dead fish, mainly eel, could be collected (Milevoj, 1997). New communities were introduced to the margins of the former lake to cultivate its floor. Very soon both the quantity and quality of the production decreased, following the severe dryness of Mediterranean summers. In the 1960s a dam and an artificial basin were built upstream, near Letaj, in order to counteract the lack of freshwater but the small water basin was soon filled with sediments carried downstream by the Bojunscica River (Rubinic et al., 1999). Since its creation the Letaj basin has undergone several emptying operations. By the early seventies it was clear that the cultural and natural landscape of Polje Cepic had undergone an expensive and inefficient transformation. The large farms occupying the polje are now abandoned and in ruin.
A lonely voice against the reclamation of Lake Arsa
Perhaps a lonely voice of its time in favour of the preservation of the lake was that of Parenzan (1928), who wrote the last naturalistic report of Polje Cepic, shortly before the drying of the basin took place. His work was partly based on a previous study by Largaiolli (1904). Parenzan compiled a short inventory of the lake sediments, flora and fauna. He reported 23 aquatic plant species within the lake and surrounding wetlands. The phytoplankton living in the lake waters included 39 diatom species and 2 species of micro algae. Among the lichens and mosses, Parenzan could recognise not less than 10 species (Parenzan, 1928). Fish also abounded in the lake with more than 10 species, of which eel was the most representative. Indeed, during historical times eel constituted a year-round predictable resource for the fanners settled on the shores and margins of the polje (Nacinovic, 1984, Parenzan, 1928). Crustaceans were present with 14 species. Among the small mammals only 2 species were characterised as typical of the water basins, while over 7 species of birds were identified as well as 5 species of reptiles. In his work, Parenzan stressed how the lake, which was a unique landscape, remarkable in scientific as well as touristic terms, would have disappeared. In stark contrast with the negative image promoted by the supporters of the draining of the lake, this contemporary picture drawn by Largaiolli and Parenzan, gives the image of a healthy water basin occupying Polje Cepic. The lake and the surrounding wetlands were characterised by an extremely high biodiversity and represented a source of revenue and secure income for the people living on its margins (Parenzan, 1928). The elders who live around the polje can still recall the period when they used to play, swim, or fish in the lake.
THE PRESERVATION OF ARCHAEOLOGICAL AND PALAEOENVIRONMENTAL REMAINS WITHIN AND AROUND POLJES
The dewatering of the polje caused a series of medium and long term issues. The water stored in its sediments and soils could support agriculture for a few decades after the drying of the lake. Now, during the summer, the water table is about 3 to 5 meters under the soil surface. This occurrence has a deteriorating consequence on the local agricultural communities in constant need for water during the summer. It is not unusual hearing them saying "if it does not rain within the next two weeks, most of the harvest will be lost".
The drastic lowering of the water table has also been detrimental to the preservation of palaeoenvironmental evidence and archaeological sites hidden within the sediments under the polje floor. Part of the archaeological and palaeoenvironmental records is missing and our chances of retrieving preserved organic remains within archaeological contexts are drastically decreasing as the water table lowers (French, 2003). Within the Mediterranean realm, poljes have great potential for preserving palaeoenvironmental and archaeological data. Such information is necessary to investigate the origins of this cultural landscape as well as precious for understanding the formation of the Mediterranean landscape as a whole. Poljes constitute optimal features for developing a geoarchaeological approach to the study of landscape change within karstic regions. The geoarchaeological project being developed in polje Cepic aims at recovering as much evidence as possible regarding the communities which contributed to its formation and transformation throughout time.
Geoarchaeology of Polje Cepic
The present paper draws from the results of ongoing geoarchaeological research within Polje Cepic. In the framework of such research, several sites covering the time span from the Late Palaeolithic to the Neolithic period were recovered (ca 25 000 to 5000 years ago). Lake sediments were extracted from the polje floor, obtaining a sedimentary sequence covering the last 8000 years. Evidence has been collected from Polje Cepic to understand its past and help plan its potential future developments as a cultural and natural landscape. Palaeoenvironmental data were gathered by drilling a core through the sediments preserved within the polje, while archaeological data were collected through the systematic survey of its margins. This research has proved the antiquity of this wet landscape and its long-term occupation by human communities. An insight on the possible reasons for the progressive infilling of the lake previous to its artificial draining has also been gained through this research (Balbo et al., 2004). I present hereafter some of the information on the past of Polje Cepic and its people gained from its geoarchaeological study.
The neotectonic depression represented by Polje Cepic has been occupied by a wet landscape for at least the last 8000 years. A lacustrine environment has characterised the area, intercalated by short periods of very low or absent water. The analyses carried out on the sediments suggest that the water body and surrounding vegetation underwent rapid changes during this period of time. Based on the radiocarbon dating of the sequence it is now apparent that between 4000 years ago and the present day sedimentation tripled, compared to the previous 4000 years. This situation is in accordance with the model proposed by Oldfield et al. (2003) for the central Adriatic, and can be similarly explained as a combined result of more intensive rainfall and clearance of slope vegetation cover beginning in the Bronze Age (Balbo et al., forthcoming).
The archaeological survey recently carried out on the margins of Polje Cepic gives strong evidence for the presence of settlers around the polje during the last 25 000 years (Balbo, 2006). Several archaeological sites from the Palaeolithic, Mesolithic, and Neolithic periods were recently found and complement the numerous cave sites previously excavated in the region. The Bronze Age is well documented by previous studies on fortified settlements and contemporary field systems (Bandelli, 1977, Skiljan, 1980). Some of the sites recently found on the margins of the polje may date to the 7th millennium BP, and be associated with the Late Neolithic horizons of nearby cave sites. In particular, the lithic assemblage from one open-air site, discovered near Frankoli, presents obsidian artefacts that could be associated with those found at Pupicina Cave, only a couple of kilometres northwards of Polje Cepic (Balbo, 2006, Balbo et al., 2005, Miracle & Forenbaher, 2005). The evidence from Pupicina Cave attests to the exploitation of well differentiated resources during the central phases of the Neolithic, during the so-called 'Danilo culture' period (7500 to 7000 years ago), including land snails and fish. The use of fish is attested through the presence of fish bones in the Middle Neolithic layers and from isotopic analyses recently carried out on the people occupying the cave at the time (Paine & Miracle, 2005). A hint about the kind of fish those people were eating is given by the representation of a European eel (Anguilla anguilla) head on a potsherd also found in the Neolithic layers at Pupicina Cave. It is most likely that Neolithic people frequented Arsa Lake on a seasonal or more flexible basis with different purposes, including the gathering and perhaps cultivation of plants, as well as hunting and fishing. There is no direct evidence so far of fishing in the lake during mid Neolithic times. Remains such as fish traps and boats are likely to be buried under the lake sediments, but their preservation is being seriously threatened by the progressive lowering of the water table on the polje floor.
MOSAIC LAND-USE: THE EXTINCTION OF A CULTURAL LANDSCAPE
The communities living on the margins of poljes adapted, throughout time, to their seasonal hydrological variability. They developed what I call here a mosaic land-use, made of differentiated and sustainable strategies for exploiting seasonally mutable resource availability, exploring new products and techniques (Rockwell, 1994). On the margins of active poljes, as Cernizko polje in Slovenia, we can still observe rural communities with a mosaic economy based on fishing, hunting and gathering, as well as on herding and cultivating. Here, the fields that are ploughed during the dry season, are covered in water during the wet season and become fishing ground. Far from being a limitation factor, the variability of the polje environment is necessary for the coexistence of such cultural and adaptive strategies exploiting a rich and constantly renewing ecological system. The radical transformation of such variability, through drying, can be a stroke to the survival of local communities and their relations to landscape and land-use (Rockwell, 1994). The difficult-to-reverse drying of wet landscapes is also threatening the preservation of their archaeological and environmental remains, which testify to the cultural richness of land-use strategies based on their high biodiversity (Head, 2000, Wenz, 2001).
Such interventions as the drying of Polje Cepic, and trying to convert multi-resource based communities to hyper-specialised agricultural ones, have a strong impact on their cultural and material traditions. A wide context, composed of objects, techniques, stories, and gestures related to both the lacustrine and the terrestrial worlds is suddenly mutilated of its central factor, the shallow lake and wetlands, and the particular way of life related to them. The material culture loses everything related to the wet landscape such as small sailing boats, canoes and fishing equipment. Only a few elderly locals can still remember myths and stories related to the lake, its variable water level and the ways of preserving it, or the very cold winters during which they could cross the lake on skates. Despite the non occurrence of engineering interventions, some of the Mediterranean poljes are nevertheless drying up. We are literally assisting the rapid extinction process of a central landscape feature throughout the Mediterranean. The evolution of poljes through time, considered as natural as well as cultural landscapes, needs to be investigated before planning their preservation or transformation. A clear understanding of how people interacted with them in the past seems necessary before engaging in large engineering interventions (Geeson et al., 2002). The pathway I decided to take in order to investigate the past of polje landscapes and their people is that of Geoarchaeology. This discipline seems to me the most suitable for investigating the natural and cultural aspects of a landscape in a long-term perspective, thus assessing the interrelation among the factors that contributed to its formation and transformation (Goudie, 1989).
THE GEOARCHAEOLOGY OF POLJES: CULTURAL LANDSCAPES IN THE MEDITERRANEAN REALM
Shallow polje lakes have been, and are still, slowly disappearing from the Mediterranean landscape, together with their way of life, cultural and archaeological characters. A study of the past of these wet landscapes can help us foresee their reaction to expected changes in climatic and land-use conditions. Their geoarchaeological study can inform us on the relationships people entertained with such mutable landscapes in the past. In the light of such results we can better evaluate their management in terms of cultural, archaeological and environmental heritage, avoiding unsustainable difficult-to-reverse transformations (Wild, 2003).
I wanted to bring forward the central role geoarchaeology can play in approaching 'atypical' cultural landscapes in order to assess alternative solutions for their management and survival. I propose to consider poljes as a material as well as an immaterial heritage made of cultural identity and long-term adaptive strategies to constantly changing environments. This heritage is composed, among others, of an extremely rich archaeology, directly linking us to universal issues such as the spread of modern humans and agricultural practices. The gathering of such knowledge has an important role to play in the shifting sustainability of Mediterranean regions, from agro-pastoral to industrial economy and tourist resort. The present research allows us to understand the story of a relevant Mediterranean cultural landscape, keeping its memory alive, and sensibly planning management for similar areas in other Mediterranean regions (Simmons, 1996).
Polje Cepic is located in Istria, a rapidly developing region, and is presently being crossed by a gas pipeline connecting the Adriatic to Zagreb. Close to this gas-route are two major sites (one Mesolithic, the other Neolithic) and the position of the extracted core. Had it been integrated with this research, the development process of the pipeline could have allowed us to recover further data regarding the environmental and cultural past of Polje Cepic. This line of action seems even more appropriate considering the pace at which tourist resorts and industrial centres are being developed, potentially uncovering and destroying the archaeological and palaeoenvironmental records.
Many poljes are still active in the Mediterranean region. With this paper, I tried to show their potential as cultural landscapes where archaeological and palaeoenvironmental research can be developed. I hope that their valuable and representative cultural character captured some attention on these 'atypical' but nevertheless endangered landscapes, scattered all over the karstic environments of the world, and of central importance in the Mediterranean realm. Poljes constitute ideal places for the study of the formation and transformations of Mediterranean landscapes, in particular concerning the long-term preservation of natural freshwater basins in karstic geological backgrounds. I believe that the joint study of environmental and archaeological records provides an invaluable framework for understanding our present position as we face important land and water management choices in cultural landscapes of the karstic and Mediterranean realms.
This page compliments of Marisa Ciceran
July 18, 2007;
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