Argon Pedion

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Argon Pedion (Greek: Ἀργὸν Πεδίον, lit. 'untilled plain') is the geological name of a "closed karst basin" in the Arcadian highlands in the Peloponnese peninsula of southern Greece. This name was already used in the passed down publication of the ancient geographer Pausanias (110-180 AD). He called it untilled plain, because grassland and acres may be flooded beyond the time, when annual vegetation starts. When winter rains are very heavy, floods can even turn into temporary lakes. Intensive karst formation (drainage in underground waterways of limestone layers) prevents a permanent lake. In rare cases, even today, modern technologies can not prevent flooding, such as on the Peloponnese, in Italy or Portugal.

Arcadia is in fact a country, where herding and some farming have dominated in all times. However, since classical roman time: for the people, who don't live there, the country symbolizes pure, rural, idyllic life. But in reality it is a permanent struggle for existence within the difficult mountainous Greek environment. Nevertheless, some progress in Arcadia is also achieved in Argon Pedion.

The Polje Argon Pedion
Temporary lake in Argon Pedion, A7 motorway. Ditch to ponor (10 tree tops in water, front left)
Totally green in springtime

Geography[edit]

Environment[edit]

The prefecture Arcadia (Νομός Αρκαδίας) is almost entirely rural and mountainous (Arcadian Plateau). The villages are scattered all over the land; there are only very few cities, even the largest city Tripoli, Greece, with ca. 50 000 inhabitants is relatively small. Steep mountains and forests are scarcely populated. Extensive forests dominate in the central north (Mainalo) and the central south, following the prefectures southern border which marks the mountain chain of the Parnon, way down to the coast of the Argolic Gulf. Valleys divide the mountain chains, but they are important draining paths only from November to April. During the dry period many brooks even dry up totally. The size of the valleys indicate, there were larger water quantities in earlier time periods.

On steeply inclined slopes the topsoil is often drastically eroded, only degenerated shrubland prevails. Alluvial sediment deposits are scarce. Accumulated soil structures are found only in plains, basins or flat coastal sections.

Climate[edit]

The climate of the Peloponnese is similar in all parts, the temperature varies only in relation to the height. The influence of the Mediterranean Sea is omnipresent, as no point of the land is at a lager distance than 50 miles. The climate is best classified as mediterrranean with dry hot summers and mild wet winters. As the dry season may last for months, the thin rests of soil on mountain slopes are merely covered by Maquis shrubland, often of a degraded character.

Even then, forests, when healthy and dense, are only mildly more humid and cooler. Very dominant is the intensive karstification, which is present throughout. This dries out the humidity of soil; the closed character of the karst basins may cause floods, as subterranean drainage can be too slow. But during the relatively short spring time the rain of the last winter and mild temperatures may result in a very beautiful, blossoming seatson, where the biodiversity of Arcadian landscapes will show (April, May).

Economic developments[edit]

As intensive dry summer periods nay cause severe lack of fresh water, retaining it in reservoirs would be an important contribution to public health by supplying sufficient drinking water at all times. At the same time publicly supplied water for irrigation and, eventually, for electricity from power stations, could help to develop the country. Even so, there are no planned or realized projects of the kind in Arcadia (exception: Earlier floods in the very large Tripoli Karst Basin, which often caused the rise of the temporary “Lake Taka”[1] have been collected in a dammed pond. Tripoli also cropped large quantities of drinking water from an aquifer - against the will and the interests of the village Sagka[2] nearby). The majority of the people in their rural environment, making their living by herding or agriculture, often lack the means to improve, or irrigate with technology.

Forests, often in mountains, where access is difficult, are rarely economically cultivated. For care, cleaning up and re-forestation after forest fires[3] (devastating in dry periods) resources for personal and tools are not available.

The land, which is suitable for herding or agriculture, is locally cultivated in traditional forms only, yielding just enough for a modest sustenance. Systematic public support, which could help to produce surplus value is rare. A realized example of economic development is the joint coastal project of the prefectures Arcadia and Argolis for irrigation with fresh water. In the big submarine (!) spring “Anavalos” at Kiveri, (Argolic Gulf), the sweet water is so good, it needs no chemical treatment. It is transported in a large concrete canal to the important, fertile coastal plain of Argos.[4]

There is no industrial production in Arcadia. There was migration in all of Greece, in the Peloponnese and also in Arcadia's Argon Pedion, mainly after 1945 to North America and Australia. But it did not really solve the problem. In the sixties of the last century job migration, induced by the German economy, rose migration to another peak. The shrinking of the population of Arcadia continues. Urbanization, a more recent tendency, is also observed in the prefecture. Tourism, heavily promoted by the Greek state, prefectures and local administrations, has no major effect on Arcadia, exceptions: some coastal hotel business and tourists with classical Greek education.

The infrastructure of transportation is miserable. While one heavily frequented highway connects Athens with Patras along the Corinthian Gulf, there is only one other modern highway (motorway), connecting Corinth with Tripoli and the south (two divisions, Messenia and Laconia). The partly tolled motorways, are the only constructions, where the very mountainous, difficult topography of the Peloponnese does not dictate the route. But considering the current traffic across the Peloponnese, the dual carriageway capacity will be oversized for a long time to come. The topography makes road or railway construction expensive. Financing a modern network for public transport, for railways and a countrywide road system for the Peloponnese is impossible. The only railway line supporting Arcadia and the south (Corinthia-Tripoli-Kalamata), a narrow gauge railway, was partly refitted and then – before operation – liquidated, including goods traffic. This network deficit limits the development of markets for profitable, regional agrarian production. Migration, urbanization and the miserable regional roads weakens agrarian orientation, also that of the Argon Pedion.

The polje Argon Pedion[edit]

The karst basin Argon Pedion (a polje similar to those in the karstic Dinaric Alps) is a neighbor basin (4 x 2 km) in the north east to the large “Tripoli Plateau” (30 x 6 km) in the high Arcadia.[5] Two mountains, opposite to each other form a 250 m wide flat, but with a lift of 5 m at the south end of Argon Pedion, this made the plain to a closed basin. Consequently, only floods with a water level higher than 5 m can be drained aboveground. The rain down the mountains fills the draining ditches, then floods the untilled plain (grass land), making the soil sucked with water. Exceptionally large rain waters may swell up to a temporary lake, whose upper border may not or may reach the acres in the slightly higher upper basin section, that is cultivated by the village Sagka. The subsurface drainage (see below the section “Geology, Hydrogeology”) may be so slow that it will extend into the vegetation zone (April).

The grass land is ideal for herding sheep and goats, as a ground sucked with water makes a wanton grass vegetation, that dries up later in the dry period. With the “cows of the poor” many people of the two villages at the borders of the basin make their living. When the grass land is dried up, especially the goats, well known for their abilities to undemanding feed and easy digesting, weatherproof in hot and cold and climbing well even on bare rock may move to the mountain slopes, where they can feed on sparse vegetation of shrubs. Yet this bares the danger of overgrazing, as plants are kept down by preferred feeding of all kinds of buds.

The villages of Argon Pedion[edit]

In many Greek villages styled fountains and a threshing floor are dedicated, vivid symbols of rural identification and tradition: See the photo of the spring water fountain at Nestani (φιλίππεοις Κρήνη), a rebuilt remnant of King Philip II of Macedon (382-336 BC) and the photo of village Sagka with three traditional Threshing floors (choros, Greek for dance: Χορός). The circular threshing floors, indicated by stone circles, were the locality, where the villagers joint for dancing after a successful harvest. In our times the word “choros” still characterizes the very popular Greek group dance. Any dancing floor in contemporary Greece is called “Chorostasi”, Χοροστάσι.

The village Nestani on a slope at the south end of Argon Pedion is focused on the untilled fields, the grass land for sheep and goats. In our age of urbanization and increased motorized mobility, where extensive and intensive land cultivation are on the decline, Nestani became more interesting as the place of residence and commuting to work in Tripoli or vicinity.

The village Sagka remains focused on its cultivating the fertile soils of the upper basin, even so the low level of mechanization and the declining importance of traditional land cultivation is imminent. However, around the village, on alluvial grounds and on slope terraces, where the soil is as rich as in the plain, ambitioned villagers successfully established gardens and niche-plantation for which they developed new regional market chances.[6]

Geology, Hydrogeology[edit]

Geology of Greece und Peloponnese[edit]

Beginning at the border of Montenegro with Albania starts the geological massif of the “Hellenides”, which cover all of Western Greece, the entire Peloponnese[7] and, in a large bent across the Aegean Islands, West Anatolia. The geotectonic phenomena are characterized by the development of faults, overthrusts and regional metamorphism in a very large timespan: Mesozoic to Middle Miocene. Tectonics created the „Olonos-Pindos“-Zone und die „Gavrovo-Tripolitza“-Zone, together a prolonged carbonate platform, of which the geologist Jacobshagen says: “The Hellenides are a mountain chain of overthrust per excellence.” “Nappe transport was very large in Western Greece. For the West Hellenic nappes as well as for the Pindos nappe, 80-100 km are minimum amounts.”[8]

This Carbonate platform also characterizes the mountain ranges of Arcadia and thus the closed basin Argon Pedion. There are several karst plains (high plateaus) formed between the various mountains of the prefectures of Corinthia and Arcadia and one plain in Achaia, Messenia and Laconia respectively. Smaller local fault movements turned the “intra mountain lows” into “closed karst basins”. These karst formations, of which there are several in Arcadia, are basins, where one or several katavothres (ponors) allow subsurface drainage.

Physical and chemical weathering and all kinds of water erosion washed the surfaces of the mountains,[9] over time, accumulating layers of loose sediment on the rocky floors of the basins. Over long time the carbonate platform, dominantly layers of limestone (often composed of remains of marine organisms), became heavily shattered by tectonics. The sedimentary limestone rock, being highly soluble in CO2 enriched water, undergoes the typical karst process: more or less CO2 enriched rain water seeps into the cracks and joints of the shattered limestone layers and solutes the stone. The cracks and joints become wider and wider, dikes, underground brooks or rivers, even water caves may result. In large formations, reaching down and lateral over several layers, voids of all sizes are created: pores, joints, caves. These are groundwater reservoirs, also called karst aquifers. The water filling of a groundwater reservoir, its so called “water table”, may vary, This depends on the quantity of rain, on clocking debris or other properties of subterranean waterways. Important large subterranean waterways between the Arcadian highland and the Argolic Gulf formed. These were results of tectonic faults. The existence of such faults have been backed up by a large geological study, which had the Arcadian karst basins as subject. The distribution of the subsurface karst waters and the retention time in the karstic underground, until the water emerged again in large springs at the Argolic Gulf, was quantified and verified by several dye tracingtests in 1983.[10]

Hydrology and Morphology of Argon Pedion[edit]

Although the karst water of spring “Anavalos” at Kiveri emerges in the sea water of the continental shelf it is sweet water of surprisingly good quality: The chlorides have an extraordinary low value and thus the water is suitable for irrigation. Since the emerged water quantity is large,[11] a 5-meter broad concrete canal was built to transport the irrigation water over 15 km to the extensive fertile low plain of Argos, where thousands of farmers cultivate the plain. It is interesting, that de reemerging of the karst water of Argon Pedion in the large submarine spring Anavalos was already known by the ancient author Pausanias. He refers to the Argon Pedion and to the spring Anavalos, which, in his publication, is called “Dine”.[12]

The soils of the karst basins are fertile. The top layers mix with loose sediment and further down with finer grained particles like sand. In these particles water seeps slower, but it is also stored like in a sponge. Below this there is a layer of irregular thickness of finer and finest grained particles: Weathered limestone particles like marl, silt, loam and/or clay, and Minerals. The water permeability of these materials varies, seeping may be drastically reduced, this will generally allow an “upper aquifer”, as can be seen on the photo, where the water table is visible in the old irrigation well. When the seepage into the rock layers is slow, but possible, an aquifer is called “aquitard”. When the capacity limit of the upper aquifer is reached, and more water is supplied, the flooding starts. In rainy winters there may be more water than the only one katavothra, which opens in the limestone rock wall below the village Nestani, can drain rapidly enough. A temporary lake will be created. It happens, that the mass of water will not all be drained by the beginning of spring time.[13] This phenomenon of a temporary lake in Argon Pedion is documented for the years 2003, 2014 and again March 2019.[14] The not obstructed subterranean water transport from the katavothra to the springs at the Argolic Gulf takes ca. 190 hours.[15]

Floods that swell to the size of a temporary lake in a karst basin can in many cases be avoided with modern technologies. But there are also situations, where technical measures fail or are too costly. Then, even today, a lake of that kind may form: E.g. in other basins of the Peloponnese, in Portugal, in Italia or Slovenias Dinarides.[16]

Anthropogenic developments[edit]

The people of the villages Nestani and Sagka secured their livelihood in accordance with what the plain and its environment facilitated. Cultivating the ground and proper treating the available water resources reflected the local opportunities. On slopes and alluvial soils around the villages, which have favorable grounds as in the plain, the people cultivated gardens and terraces. A good example for creativity and successful entrepreneurship is the building of new terraces and planting of nut trees on a suitable slope, that had enough soil. For the plan to be successful, it was only essential, to make provisions for a steady water supply. For the rich harvest of walnuts the local motorway to Tripoli, Kalamata and Sparti, but most notably to Corinth and Athens opened aspects for expanding agriculture beyond traditional limits and finding a market niche. Meanwhile, the engaged people of Sagka are expanding to grow standard products like vegetables on their terraces for sale in local markets. The entrepreneurs have established webpages to promote their ecologically oriented projects.[17]

The care necessary for cultivating and watering the plain in the dry summer period was achieved by walled irrigation wells with chunky shovels. There were wells distributed across the whole plain. The metal is now rusty, the wells are rugged constructions, but no longer in use. Where necessary and affordable these tools are replaced by motorized pumps. The people cultivating the terraces had a good idea for energy-saving automation of the watering. They made use of the incline of the slopes by placing a water tank on top and stretching the retention of water for irrigation over the whole rain season. Apart from single initiatives, the mechanization of agriculture, measured by international industry standard, is still rather modest.

Drainage ditches are everywhere in the plain and obviously important to prevent it from becoming swampy, but taking care of holding the water table and the proper humidity for grass land and acres as long as possible is another thing. All drainage is towards the one single kathavotha. That is why excessive precipitation in case of intensive winter rainfall often exceeded the capacity of ditches to swiftly transport the water and the Katavothra to swallow it. Advanced knowledge, machinery and methods beyond smallholding agriculture were implemented: New ditches were dredged, all ditches well cleaned, a row of trees planted to strengthen the ground. The 5 meter opening of the katavothra in the massivel limestone rock was sheathed by a strong metal lattice. However, to change the ca. 50 km long subterranean waterway to the re-emergence in the submarine spring Anavalos at Kiveri has not been attempted. Speleologists have operated the cave only up to the first siphon. Exploring and improving the conduit to enlarge the water transportation capacity is anyway impossible - even with most advanced technologies.

The construction of the motorway A7, Corinth-Tripoli-Megalopoli in the nineties of the last century, now finished close to Kalamata and Sparti (2019), left the fragile ecology and eology/hydrogeology of Argon Pedion untouched. Rocky slopes were cut to keep the roadway some meters above a potentially high rising temporary lake water level. But on one section, ca. 900 m, the road embankment is just high enough, not to be flooded, but it cuts the basin. The ditch to the katavothra is bridged. This section of the motorway is seen in the photo (the ditch is flooded, but 10 tree tops rise above the water level).

History of Arcadia and Argon Pedion[edit]

The ancient geographer[edit]

The publication of Pausanias (120-180 AD), handed down in Hellenistic Greek (Ελλάδος περιήγησις), also available in German and English translations (Description of Greece), describes in Book 8, Arcadia, and explicitly also Argon Pedion.[18] Actually, the name “Argon Pedion”, the modern Greek term for “untilled plain”, is the term Pausanias introduced in his publication.

Pausanias describes the ancient road, which starts at the ancient city of Argos, ascending the mountain chain Artemisio to the “Portitsa-Pass” and then, abruptly downhill, the zigzag descent into the basin of Argon Pedion. The zigzag path is still there and visible (see the photo “Ladder”). Pausanias describes the “Ladder” (Κλιμαξ Παυσανία) with a detail about its steps.:

[4] There is a pass into Arcadia […]. There are two others on the side of Mantineia: one through what is called Prinus and one through the Ladder. The latter is the broader, and its descent had steps that were once cut into it.[…].

Pausanias, Book 8, Arcadia, 8.6.4, English by W.H.S. Jones/H.A. Ormerod, London 1918

After crossing into Mantinean country over Mount Artemisius you will come to a plain called the Untilled Plain, whose name well describes it, for the rain-water coming down into it from the mountains prevents the plain from being tilled; nothing indeed could prevent it from being a lake, were it not that the water disappears into a chasm in the earth. [2] After disappearing here it rises again at Dine (Whirlpool). Dine is a stream of fresh water rising out of the sea by what is called Genethlium in Argolis.

Pausanias, Book 8, Arcadia, 8.7.1f, English by W.H.S. Jones/H.A. Ormerod, London 1918

Argon Pedions untilled plain and a spring fountain, that the Macedonian King Philipp built next to the ancient city Nestane are described. The tradition of today's village Nestani keeps a reminiscence of the historical fountain in its center.

… on the left of the plain called Untilled is a mountain, on which are the ruins of a camp […] it is said that by this Nestane Philip made an encampment, and the spring here they still call Philippium after the king.[…]

Pausanias, Book 8, Arcadia, 8.7.4, English by W.H.S. Jones/H.A. Ormerod, London 1918}}

Pausanias’ time obviously had a basic knowledge of the hydrology of the untilled plain and the re-emergence of the water in the submarine spring Anavalos in the continental shelf of the Argolic Gulf (Anavalos was then Dine).

The ancient Portitsa-Pass is an impressive human made monument: A 6 m deep incision in the rock at the mountain crest, 3 m, broad enough to give way to a wagon, of which rests of wheel tracks were discovered[19] The descent on Pausanias’ Ladder in ancient time was a zigzag wagon driveway, of which the historical upper section still exists. Today a modern zigzag driveway allows access for heavy transportation (electricity pylon). A webpage, unfortunately solely available with German text, is very instructive, however, for its photographic illustrations of ancient remains and modern views.[20]

The Greek geologist I. Mariolakos published two articles (in Greek and in English) combining geological knowledge about the karst basins of the Arcadian Plateau (including Argon Pedion) with classical myths of the same territories. He documented surprising similarities between myths and geological facts.[21]

The Renaissance of Arcadian idyll[edit]

A remarkable interpretation of Theocritus’ “idyll” was given by the roman poet and epics writer Virgil. He took the idealized Sicilian rustics and set them in Arcadia. For him Arcadia was the homeland, where idyll had its origin. The idea was “reborn” in the Italian “Renaissance”, supported by the enthusiastic patron Lorenzo de' Medici. Arcadia, the “Country of the Shepherds” inspired Italian poetry (Poesia bucolica) and became a very important literary genre. The leading painter Nicolas Poussin, French, but living in Rome, had a lasting impression not only on the baroque epoch of art. His two versions of the painting “Et in arcadia ego” (e.g. “Even in Arcadia, there am I”) symbolize pure, rural, idyllic life, peace and death. Ever since then and to the present this kind of blissful idea of self-complacent shepherd life is Arcadia, the Greek country, that is not a classical Greek city state, an “idyll” that is alive – especially among many “Classically Educated”.

References[edit]

  1. ^ Wikipedia has only a Greek version with excellent photos, though: “Λίμνη Τάκα
  2. ^ See the villages webpage “Sagka village Argon Pedion” in External Links
  3. ^ See e.g. the mountains after a forest fire in the photo Image:Arkadia idyll Peloponnese.jpg
  4. ^ See the section Geology further down
  5. ^ In his publication the Greek geologist I. Mariolakos describes several parts of the Arcadian Plateau and compares them with the classical myths, which are broadly present among Greeks. (See External Links)
  6. ^ See “flourishing walnut plantation” in the section “anthropogenic developments” below
  7. ^ except the northeast of the Peloponnese, an area, which is basically identical with the prefecture Argolida
  8. ^ Jacobshagen, p. 52. See the section Literature
  9. ^ once vegetation is poor on slopes, capacity to hold or create new soil is weak
  10. ^ Morfis et al, p. 276ff, see Literature
  11. ^ The tectonic faults transport karst water from basins in Corinthia and Arcadia. See also the graphic of Image:Orohydrography_NE-Peloponnese_detail.jpg
  12. ^ See the section “History of Arcadia and Argon Pedion”, further down
  13. ^ Ford… Karst Hydrogeology and Geomorphology…, p. 361ff, see Literature
  14. ^ See the photo above at the top of the article Image:Karst-lake_Argon-Pedion_Arcadia_Peloponnese.jpg
  15. ^ Geomythological sites, Mariolakos, p. 16. See External Links. See also , available only in Greek
  16. ^ See Lake Stymfalia; see Minde (Alcanena); see Doberdò del Lago and Image:Cerkniško jezero-3.JPG in the carbonate platform Dinaric Alps
  17. ^ See below under External Links: A prospering nuts plantation of Argon Pedion
  18. ^ Description of Greece, Book 8, see Literature and External Links
  19. ^ See Klimax road… in External Links
  20. ^ See “Porta Artemissiou” in External Links
  21. ^ See the two publications by Mariolakos in External Links

Literature[edit]

  • Cvijić, Jovan, Das Karstphänomen. Versuch eine morphologischen Monographie. in: Geographische Abhandlungen A. Penck, (Hrsg), Bd. V, Heft 3, Wien 1893. German
  • Jacobshagen, Volker (ed), Geologie von Griechenland, Beiträge zur regionalen Geologie der Erde, Stuttgart, 1986. German/English
  • Pausanias, Description of Greece, English Translation by W.H.S. Jones + H.A. Ormerod, London, 1918.
  • Morfis, A. (Athens), Zojer, H. (Graz). Karst Hydrogeology of the Central and Eastern Peloponnesus (Greece). Steirische Beiträge zur Hydrogeologie 37/38. 301 Seiten, Graz 1986.
  • Lehmann, Herbert, in: Fuchs, F., (ed), Karstphänomene im Nordmediterranen Raum, (1973), Beiträge zur Karstmorphologie, Herbert Lehmann; Reprint noch aktueller Beiträge, Stuttgart 1987 German
  • Ford, D. C. and Williams, P.W., Karst Geomorphology and Hydrology, London 1989.
  • Mariolakos, Ilias. The Argon Field in Arcadia, the sinkhole of Nestani, God Poseidon and the submarine Dini Springs in the A rgolic Gulf (Peloponnisos, Greece). A geomythological approach of the Poseidon's birth. Bulletin of the Geological Society of Greece, Proceedings of the 10th International Congress, Thessaloniki, April 2004.
  • COST 621, Final Report, Groundwater Management of coastal karst aquifers, Brussels 2005.
  • Gunn, J., Encyclopedia of caves and karst Science, New York, N.Y., 2005.
  • Pentecost, A., Travertine. Springer-Verlag, Berlin Heidelberg 2005.
  • Ford, D. C. and Williams, P., Karst Hydrogeology and Geomorphology, Chichester, 2007, 4th, rev. ed.
  • Mariolakos, Ilias. Geomythological Sites and Prehistoric geotechnical and hydraulic Works in Arkadia, 12th International Congress of the Geological Society of Greece, Field Trip Guide, Patras May 2010, Greek

External links[edit]