Správa národního parku Podyjí

You can learn more about the formation of the landscape on the south-eastern edge of the Bohemian Massif in the area which is now covered by the Podyjí NP before the end of the last Ice Age from the publication “A Geological Map of the Podyjí and Thayatal National Parks with Explanations” (R. Roetzel, 2005).

The main factor which helped to form the landscape in the Tertiary Period was the definitive retreat of the sea, which began around 11 million years ago. Another main factor was the lifting of the edge of the Bohemian Massif, which took place at the same time as the subsidence of the Alpine Foreland between 5 and 1.5 million years ago. This change in the relief and the formation of a distinctive step at the south-eastern edge of the current Podyjí NP led to the gradual deepening of the Dyje river valley. This process continued down into the crystalline bedrock and resulted in the formation of a deep river canyon with well-developed meanders. The existence of such a canyon-like valley is the fundamental factor in the further development of the region’s landscape.

With the onset of the colder periods in the Pleistocene (Ice Ages), the erosion and physical weathering of the rocks accelerated. The valley with very few trees and woody plants was exposed to the effects of the wind, including large temperature variations. Distinctive landforms such as boulder fields, rock pillars and castle koppies developed in these conditions due to the effects of water and frost. The process of deepening the river valley also accelerated. The plateaux to the north of the river, as well as the gentler leeward valley slopes were covered by wind-blown loess sediments. At the beginning of the damp Boreal period, after the end of the Ice Ages (around 11,000 years ago), the loess on the valley slopes was broken up as deep gulleys were eroded into it. Tertiary marine and riverine sediments, as well as the younger loess deposits, were also eroded and carried away from the south-eastern slopes of the Bohemian Massif – the current heathland areas between Znojmo and Retz. This erosion led to the exposure of the older, pre-Tertiary surface, which is formed of deep effusive rocks. These volcanic rocks have a sparse soil covering, consisting of the remnants of sediments which have not been carried away. Deeper soil is only found around the current villages. The shallow soils on these gentle, rocky slopes around the villages, which we now call the Znojmo-Retz Heathland Belt, have been primarily used as pastures ever since the first farmers settled here thousands of years ago.

This area was very sparsely settled during the last cold period in the Pleistocene, although material evidence of the presence of Neanderthals around 40,000 ago can be found at suitable sites above the river valley. Evidence of the presence of modern humanoids, such as the Cro-Magnon hunters has not been found in the area, because their large Pleistocene prey animals mainly lived on the flatlands of the South Moravian River Basins to the east. The development of this landscape in the Postglacial Period is described in the publication “Protected Areas in the Czech Republic – Brno Section”.

During the warmer and damper period of the Postglacial – the Atlantic Period, which began around 8,000 years ago, the process of development of deciduous forests reached its peak and such forests already covered the majority of this area. Only the steep rocky slopes, talus fields and extremely poor localities, as well as parts of the alluvial plain, remained unforested. However, at the same time the conditions for the development of agriculture improved and this landscape has been visibly changed and modified by human activities ever since.

 

Axe-hammer head used by Neolithic farmers

 

Neolithic agriculture led to a considerable increase in population density and the face of the landscape began to change as the areas with deeper, more fertile soils were deforested. Pasturelands were mostly founded on poorer, drier localities, as well as in the forests and around the settlements. It is no co-incidence that the majority of the sites which were periodically settled by various cultures in prehistoric times are basically the same places where we can find the current villages. These localities above the Dyje valley are often at the springs of smaller streams where the soil is deeper, as well as in places which are protected from extreme weather. One of the most interesting settlement localities is around the modern-day village of Mašovice, where artefacts have been found in the loess horizon, which document more-or-less continuous settlement of the area since the arrival of the first farmers 7,500 years ago up to the present day. These finds include a cult shrine or temple consisting of a double rondel, as well as the lower body of a female fertility statue – the “Venus of Mašovice”. These archaeological finds provide indirect evidence that this landscape was already so heavily influenced by human activity 6,000 years ago that large ungulates (bison, primitive oxen) and large predators (bears) were unable to survive here.

The intensity of the agriculture increased after the development of bronze-working (around 4,000 years ago) and iron-working (around 2,750 years ago). Various crafts also developed and the new caravan trails permitted the development of long-distance trading. The population and settlement density also increased. Suitable positions on high ground above the river were transformed into fortified settlements, e.g. the headland where the Znojmo Castle now stands, Šobes, and the Ostroh headland behind the Nový Hrádek ruined castle. The high promontory at Hradiště near Znojmo has been continually settled since the Early Iron Age, through to the period of the Great Moravian Empire and up to the present day, and is of great prehistoric and historical significance.

 

Celtic tools

Around 2,000 years ago the Celtic inhabitants were forced out of the area by Germanic tribes. The northern border of the Roman Empire (Limes Romanum) ran along the Danube valley around 60 km south of Podyjí and the area in front of the border witnessed frequent battles between the Germanic tribes and the Romans. This region was sparsely settled for several centuries, so that many previously settled localities reverted to nature. This trend continued during the Migration Period in the 5^th and 6^th centuries AD. Except for Hradiště, the central part of Podyjí remained uninhabited, with only trading routes passing through the area.

 

The arrival of the Slavs at the beginning of the 7^th century saw the area becoming much more densely populated again and all suitable localities were recolonised. Hradiště became a centre of power again, and was one of the most important population centres on the western edge of the core territory of the Great Moravian Empire. Hradiště remained an important centre of power until it was conquered by the Magyars before the middle of the 10^th century.

The peak of the Early Medieval Period saw a transfer of power from Hradiště to the Znojmo Castle on the opposite promontory. The positions of the farming settlements had already stabilised on the sites of the present day villages. As the Bohemian Kingdom grew in political strength, the system of agriculture also developed and the three-field system came into usage. Formerly abandoned localities were recolonised, meaning that many of the forests were felled as far as the edge of the canyon. The building of border castles such as Bítov, Vranov nad Dyjí and Znojmo during the reign of Prince Břetislav led to the consolidation of the southern border of Moravia. The founding of the town of Hardegg and the Kaya and Nový Hrádek Castles in the 14^th century all brought important changes to the landscape of the central section of the Dyje valley. The building of these towns and castles led to further deforestation to provide fields and meadows to feed the inhabitants, open areas to improve their defences, as well as roads and trails for access and communication. Watermills were built at suitable localities along the Dyje river, with a few more on larger tributaries, leading to further landscape modifications to provide access and space around them. Water regimes were also modified as weirs and millstreams were built to hold back and divert the water to run the mills. The valley slopes were terraced and used to grow grape vines and fruit trees at suitable localities. The area covered by vineyard terraces clearly increased until the end of the 18^th century, when vine diseases and changes in society reversed this trend. Around 90 hectares of the valley bottom along the Dyje river and the Klaperův potok and Fugnitz streams were converted into meadows, which were used for grazing or hay production until the mid 20^th century.

During the Thirty Years War in the first half of the 17^th century, the political and economic collapse in the society resulted in a dramatic reduction in the intensity of agriculture in the area and many localities reverted to nature. The re-awakening of society in the 18^th century was accompanied by the growing influence of industrial production. Water-powered ironworks and a factory producing ceramics (stoneware) were set up in Vranov and two completely new villages – Šumná and Lesná – were founded in the forest complex.

The gradual increase in the contribution of industry, commerce and services to the national product during the 19^th century also brought gradual changes to life in the countryside, and this life is still changing even today. Animal grazing was already in decline from the mid 19^th century onwards and certain agricultural products were replaced by cheaper imported goods. Some localities on the eastern edge of Podyjí were reforested, especially in the period after the Second World War.

The growth in the urban population in the second half of the 19^th century brought new lifestyles, where the townspeople had more free time. Tourist clubs and local heritage groups were founded and they began to focus on the nature and landscape of the central Dyje river valley. These first tourists visited such attractive places as the Ledové sluje (Ice Caves) near Vranov; the Nový Hrádek ruined castle and the Devět Mlýnů (Nine Mills) localities. The 20^th century also brought new projects which dramatically influenced the landscape. The Vranov Dam and Reservoir with a hydroelectric plant was completed in the 1930s. The dam and reservoir in Znojmo was completed in the late 1960s. The flow regime and water properties in the Dyje have been permanently modified ever since.

The events surrounding both world wars led to considerable plundering of the forests in Podyjí. Two lines of defensive fortifications were built in the river valley and around the villages before the Second World War, totalling more than 100 bunkers in the Podyjí NP region.

The post-war political changes, leading to the formation of an impenetrable border zone behind the “Iron Curtain” greatly restricted access and economic usage of the lands in Podyjí. This resulted in many localities becoming re-naturalized, especially areas which were previously used as meadows. The process of enrichment of nature with nutrients (eutrophication), especially from agriculture, but also transported from emissions from industry and transport, accelerated from the mid - 20^th century onwards. The socialist collectivized agriculture also led to the destruction or drastic simplification of the complex structure of the landscape, which had developed over many centuries.

The target for a protected land, which is awarded the statute of a national park, is primarily to develop the natural values towards a near-natural state and the protection of biodiversity.

Author: Martin Škorpík