Tisza River, Hungary

Over three days, from Oct. 7th-9th, the UNL-IGERT group learned about the Tisza River and the Great Hungarian Plain from our hosts/guides/teachers, Péter Balogh, and Béla Borsos. The Tisza River is the basis for a case study of a complex social-ecological system. Here's some more insight into its physical geography, hydrology and geomorphology, and a bit more discussion about the "shadow network's" story to re-connect the floods with the plain.

This post compliments the one previous (Nagykörü, Hungary). 


Béla (left) and Péter (right)

The Tisza River is a large tributary of the Danube River (both are major rivers in Central Europe). The river basin (156,000 km²) covers five countries (Hungary, Slovakia, Ukraine, Romania, and Serbia), but the Tisza is considered to be mostly a Hungarian river ("Hungary is bordered by itself" since the Hungarian Empire was separated after WWI). The shape of the basin is exceptionally important for flooding, since the arc-like shape of the Carpathians causes stormwater flowing from the tributaries to converge on the main river channel after storms in near unison. The mountains receive 3-4 times the amount of rainfall as the plains (2000 vs. 600 mm/yr). These factors make the Tisza "flashy" with flow rates changing by a factor of 50 or more, accompanied by sudden (24-36 hours) and extreme (up to 12 m) rises in river stage.


Geographic setting of the Great Hungarian Plain, surrounded by the Carpathian Mountains to the north and east (image from WorldAtlas.com)

Humans have a long relationship with river engineering along the Tisza. Sometime during the Medieval period (c. 1100-1200), a Fok-system of dikes (with sluices) was built to control inundation of floodwaters onto specific areas of the floodplain. In the 1700s, Hungarians used the floods as a means to fight against invading Ottoman soldiers. Also during that time, the Tisza was deepened and shortened (by 400 km) and more dikes were built to prevent flooding of wheat fields and settlements.  From 1860 to 2000, a series of seven construction phases occurred, in which the dikes along the Tisza were expanded and raised as a means of flood defense. Today, the dikes are 4-6 m above the river. The seven phases were required for at least two reasons: 1) The headwater regions in the mountains were largely deforested leading to less storage of water and more runoff; and 2) The floodway (within the dikes) continually aggrades (rises) over time due to sedimentation. The latter process has continued as a positive feedback until the dikes (earth embankments) reached their physical limits and now they cannot be raised any further (as evidenced by dike breaks becoming more frequent). Currently, 2700 km of dikes "protects" 17,300 km² of land along the Tisza within Hungary. In total, dikes within the Tisza River valley stretch 4500 km, and have reduced the area of the active floodplain by 90%.


Map of historic (c. 1700s) areas inundated by floods within large sections of the Hungarian plain (right) and neighboring Danube River valley (left). Péter is pointing to his village, Nagykörú (big circle). He explains to me that the village would not, in fact, have been inundated by floods during this time since it was built on a high natural terrace (relict of an older floodplain).  

Historically, settlements were situated on high lands—only later with man-made dikes did these areas become inundated by floods. Today ~$39 billion is in risk of damage by floods. Over the past 20 years, rising high waters have been overtopping the dikes. The largest and most damaging flood was in 2010. Therefore, there are real consequences, and the issue of flooding is pressing. 



The rise that the road follows is only 1-2 m higher than the surrounding land, but this is enough to be considered on "high" land, which was historically safe from floods.

Péter explaining the physical geography/geomorphology of the region and the potential for a Fok-polder system. Low elevations on this Digital Terrain Map (DTM) are in dark blue, and high elevations are in red-orange. Polders are natural depressions, or "old river beds" that have been preserved as the meandering river has migrated.

The situation for the Tisza River valley is quite bad now as the potential for devastating floods increases. Also, the river channel has degraded (lowered) its bed, thus lowering the water table during dry periods; but the dikes contain many large flows in the active floodway, and thus raise the water table during wet periods. Because of these processes, and because of the spatially varying capacity of the floodway to transmit water, during any given time there can be areas within the Tisza valley flooded and other areas in agricultural drought. Cash crops continue to be subsidized, and subsistence farming is rare to see (but it still continues to some degree). 

The vision explained to us by Péter and Béla (of the Fok-Polder system), is to adapt human infrastructure and our own desires so they balance with the provisions of the natural environment, and to stop adapting/engineering nature to fit human needs by continuing to protect against floods with dikes alone. All that would be needed are strategically located sluices in the dikes, and appropriate land use changes. 

One last statement offered by Péter: "What do you need to break a dike? ... a dike."

The Tisza River looking downstream (SE) from the ferry on the way back to Nagykörú.

Posted by Nathan Rossman

Nagykörü, Hungary

Post written by Maggi Sliwinski

On October 7th, we began the first of our three big IGERT trips. We left our hostel at 6:15am and headed to the train station, where we would begin the half-day journey to Nagykörü, a small town in Hungary where we would spend 3 days. We traveled to Budapest, where we caught a train to Szolnok, where we were picked up by our hosts Peter and Bela, plus Motszi the dog. Motszi was not too happy to have new people around, but he got used to us eventually!

Our first quick stop was at a flowing well that was tapped into the aquifer over 1000 feet below ground. The water was hot and sulfury, but Peter filled up six jugs to take home for drinking water. The sulfur smell did wear off, and it tasted good. The water in Nagykörü was chlorinated, so that's why Peter wanted the fresh aquifer water. There are apparently lots of hot springs throughout Hungary, and also some geothermal electricity capacity. The spring was also near our first view of one of the tributaries to the Tisza River, the river our trip would be focused around. The tributary was channelized, and was almost empty.

Flowing well

View of a tributary to the Tisza River

We arrived in Nagykörü where we had our lunch at the local restaurant. We were served tomato soup and fried fish and potatoes. It was a really yummy meal, but there was lots of food to eat. Lots of us couldn't finish, I just hope our hosts and the chef weren't offended by our small stomachs. After lunch we dropped our stuff at the guest house, Gazdasági Ellátó, and had a bit of free time to relax before evening workshops. The evening workshop took place in the local community center, which was a really nice building. To start us off, they served shots of Palinka, a local fruit brandy, to us all. Apparently this is a traditional practice before meetings.

Community center

Palinka being served before our first meeting.

Our cute guest house rooms.

The Tisza River is able to rise 10m (30 feet) in just a day or two during spring time with snow melting. Historically, the water would flow onto the flood plain, where it would scarcely be above my hips and only in the lowest lying areas at that. The yearly flood of the river would reinvigorate that land with nutrients and soil moisture, and would allow fish to spawn. Before the river was managed by humans, the region was widely known for its highy productive fisheries, and its huge variety of hardy fruit trees. The region was also well suited to raising cattle and pigs, since they can wade through shallow floods and consume native vegetation. What is not well suited to this periodic flooding is monoculture crops of corn and wheat.

The town was full of flowers.

The town also had lots of fruit trees, which would
have been abundant in the landscape before
monoculture cropping was introduced.

The river has been heavily managed since the mid-1800s because someone then decided that the region should be used to grow wheat, because of high demands for wheat coming from expanding cities and frequent wars. Today, the people in the region depend on the government to protect their farm fields from the river, and fear river flooding, even though it used to be the life blood of the region. There is no memory left, accept in historical records, of how the Tisza River used to be. This region is also impoverished because there are a lot of absentee landowners and corporations run the farming enterprises from afar.

One of the dikes and Motszi the dog

Our first speaker was Atilla Lovas, the water engineer for the local water district, responsible for managing the Tisza River in this region. He told us about the establishment's way of managing the Tisza River, which involves dikes, dams, and emergency reservoirs. The emergency reservoirs are low-lying areas on farmers' fields, which can only be used when the river is at dangerously high levels. The farmers are compensated if their fields are flooded. Atilla was quite proud that his agency had moved away from simply continually raising the dikes to trying to figure out how to lower the water levels through the use of emergency reservoirs. The dynamics of the river make it particularly important to manage well, although we heard from our hosts that there are other frameworks through which to view water management.

One of the control structures leading into an emergency reservoir.

Our hosts Peter and Bela, both geographers, are sifting through historical records to determine what the region used to be like, and using sophisticated models and theories to determine what the region could be like in the future. If the river were allowed to flood more naturally, and people were more flexible and adapted to the river rather than adapting the river to their demands, it could change the region for the better. Floods would not be a surprise, but a welcome re-invigoration for the land, and a locally based economy could be a means to relieve poverty. Peter and Bela are part of a "shadow network" of people who are making sure that everything is in place (research, models, planning, support) when an opportunity arises to actually shift the region to this new way of sustainable thinking and acting.

Our second day was spent at the Tisza Lake, which is actually a reservoir formed by a dam for flood control. It's a beautiful reservoir, but it's being clogged with sediments falling out of the river, making it less capable of holding high water levels. However, this makes the area a prime spot for migrating and nesting birds. The government is trying to establish eco-tourism around the lake--we were joining in a small meeting of service providers who were working on establishing more "complex" programs--such as birding tours. It was nice to be outside and it was really warm, so we enjoyed our few hours around this place. I asked Peter if this lake and tourism center fit with his vision for the Tisza River, it does not. The reservoir is part of the unnatural river regime, and it would probably not survive if the river's natural flooding regime were to be restored.

The new building at the Tisza lake.

Tisza Lake dock.

Tisza Lake

Me searching for birds....not the right time of year!

After our trip to the lake and through the new tourism centers animal exhibits, we headed out to see two oxbow lakes--one that was cut off from the flooding river and one that is still flooded periodically. The one that is flooded periodically is much healthier looking.

Cut-off oxbow lake, more clogged with trees.

Flooded oxbow lake, less clogged with trees.

On Tuesday evening, Ilonka, Shelli, Hannah, and I took the opportunity to go see Peter's horses and help him move them to a new spot. We all also got a chance to ride bareback. Two of Peter's kids came along too, although they know English they seemed very shy to talk with us. But it was heartwarming to see Peter interacting with his children, it's clear that he loves his family and his home, which is probably why he wants to see the Tisza River restored to what it used to be.

Peter and his son, plus the wild horse (that I did not ride)

Ilonka and I on horses at sunset with a crescent moon behind us.

On Wednesday morning we had a couple more presentations from Peter and Bela to talk about shifting the river out of its current management regime and to a new, more sustainable one (we also had another shot of Palinka--at about 9am!). One thing that spoke to me was Bela's portrayal of the the nested hierarchy. People often show the three-legged stool for sustainability, with society, economy, and ecology contributing equally to sustainable thinking. Bela's diagram looked like this:

This diagram is very similar to something I had come up with on my own about a year ago because I am dismayed that people think the environment is only one leg of a three-legged stool. Everything that humans need and manufacture starts somehow from the environment. This diagram makes much more sense and should help people to re-frame how they think about sustainability.

After our morning presentations, we had a chance to meet with a local goat farmer who makes hand-crafted goat cheese. We took a walk to the Tisza River and then had to head to Budapest. This trip was really awesome because we met two actors in the "shadow network" that we've read about in papers, and had a chance to see the landscape that the role-playing game is based off of first hand. It will be helpful to have this in mind when we see the game played again in Poland this coming week.

This young man sold us locally produced and hand-made goat cheese.
He milks his herd (about 15 goats) every morning, by hand, by himself.

The group (minus Marie--sorry!) with our hosts Peter and Bela.

Neusiedler See

The saline systems discussion group visited the National Park of Neusiedler See – Seewinkel, one hour to the east of Vienna and near the border with Hungary. The trip focused on the management and loss of saline waters, one of two threats facing saline systems into the near future. (The other threat is the unnatural salinization of freshwater systems, for which we visited Hallstatt – see previous post).

The park was the first national park in Austria, established in 1983. It is an agricultural region that has changed from pasturing cattle to cultivating vineyards; it has been designated a UNESCO World Heritage Cultural Site. It has also been designated a Bird Heritage Site because 340+ bird species migrate through the small region every year, attracted by one of largest reed belts in Europe.

Lake Neusiedler See on the horizon, fringed by the second largest reed belt in Europe.

Reeds are still traditionally harvested for roof thatching.

 We met Alois Lang, who has worked at the park since its inception. Using a large, high-resolution topographic model of the region, he explained the physical characteristics of the area that make it so unique. Neusiedler See is a very shallow (max depth 2.2 m, average depth 0.8 m). It is endorrheic, fed by precipitation and regulated by evaporation, though nowadays a weir ensures that the lake does not completely dry up or flood anymore, drastically changing its hydrology.

Alois Lang explains the morphology and hydrology of the Neusiedler See - Seewinkel region.

 The same strong winds push sand out of the lake onto the eastern bank, creating sandy soils that proved perfect for vineyards, changing the land use from cattle pasturing and haying to family-owned wine production 70 years ago. We saw hundreds of neat rows of grapevines on our way to the park, covered in nets, passed over by biplanes, and enveloped in a noisy ambiance of automated gunshots, all in an attempt to keep the migrating birds out of the vineyards during the concurrent grape harvest.

The sandy soil and climate of Neusiedler See are perfect for vineyards.

Next, we met with Prof. Alois Herzig, the former director of the park and biological station, and Harry, who is in charge of park education. They animatedly discussed the park’s management successes and challenges. Rather than owning land, the park annually rents the land and the right to manage it from the local landowners. In this way, the park is composed of 10,000 hectares of little islands of land surrounded by agriculture and linked together by plots of land that have gone fallow as part of a government-subsidized program, adding another 3-4,000 hectares.

Map of Neusiedler See; the green areas show the national park.

Fallow plot in between two vineyards.

The management of the land depends entirely upon the decisions of the 28 national park staff; they are not dictated numbers by government entities, such as bird population numbers or hectares conserved. If they notice something that works, they continue to do it. For example, they noticed that cattle-grazed land provided more bird habitat than mowed land or untouched land, so they paid to borrow traditional grey cattle from southern Austria and Hungary. In this way, they reintroduced a traditional land use practice in the region which also serves an ecological function.

The national park has enjoyed other successes in addition to recovering grasslands. The lake was once used as an eel fishery, introducing an exotic species that decimated the local fish population. In order to become a national park, the government required this industry be stopped, helping to recover the lake’s natural species assemblage. 

They also count successes within the community of Neusiedler See. The national park serves as a role model for sustainable land use and through the years there has been a change in the way locals value and use their land. So much of the land is now rented to the park or allowed to go fallow because it is of economic value to the whole community because of the ecotourism it brings, which supports stable jobs so young people can afford to stay in the community.

Birds and wine draw tourists to the region.

The town of Illmitz near a saline pond.

The national park faces challenges ahead. The first is money. The current budget is based on a contract between the regional and national governments, each paying 50% of a budget upon which the governments, without consulting the park, decide every year. The budget for 2014 is uncertain as both governments consider defunding both the national park and the fallow land subsidy. Should the park be unable to pay its rent to landowners – which already requires 60% of the budget – the landowners may choose to redevelop the land. The budget restrictions also leave only 3% for monitoring and 2.5% for education. The park does not receive revenue from tourism, so its land management, tourism advertising, and monitoring data rely solely on personal agreements it has made with local landowners, industries, and university researchers in Vienna.

IGERT saline systems group with Harry and Prof. Alois Herzig of the National Park.

 Ecologically, the main challenge is now water retention. Water management in the area focuses on maintaining stable lake levels and avoiding floods. Water is also free and unlimited, so sloppy water use among the farms is common. This inefficient consumption lowers the water table so much that the smaller Seewinkle saline ponds, which naturally tend to dry up in the summer, are drying up permanently because the groundwater that feeds them is now too deep. The park has lost 60 ponds in this way, and now focuses on educating the importance of saving the remaining forty ponds in its area.

Birds at a Seewinkel pond.

Seewinkel saline pond.

 Many of us were struck by how similar the region was to the Nebraska Sandhills in appearance and ecological function. This will lead to many interesting future discussions in the saline systems group about how saline systems are understood and managed.

Heading back to the city, marked by Vienna's "Home Mountain"

(Post written by Victoria)

(Photos by Victoria and Nathan)

Hallstatt

Some IGERT members have formed a small paper discussion group on the resilience and management of saline systems. These unique systems exist both in Nebraska and Austria, and we are curious about how the two compare. Two different threats related to salt and aquatic systems are predicted to become more serious in the coming decades: the loss of naturally saline lakes, and the anthropogenic salinization of freshwater lakes. We will visit examples of both of these situations in Austria. First, we visit a freshwater system influenced by salt.

Members of the saline systems discussion group travel to Hallstatt, in the western part of Austria near Salzburg. Hallstatt is part of the Salzkammergut, or “salt kingdom,” where salt has been mined for thousands of years, providing the region with economic stability and a vital natural resource. The region is also characterized by several freshwater lakes. Our mission is to learn more about how these two natural resources coexist and their socio-economic connection.

The town of Hallstatt seems tiny from the ferry, hugging the shores of the lake Hallstättersee and creeping up the surrounding mountains. The town has about 1,000 permanent inhabitants. Every morning, two fishermen cruise the lake with nets and return with the catch of the day for the locals and restaurants to prepare for dinner. Swans, introduced to the lake to please Empress Elisabeth when she would vacation here; today they cruise the lake looking for handouts from the peasant tourists.

We ascend a nearby mountain to visit the local salt mine. Hallstatt has been a mining center since about 7,000 years ago, and this is thought to be the oldest salt mine in the world. Neolithic people mined the salt to preserve meat; this area became one of the first known human settlements, and its archaeological importance is recognized by an era of time named after it (Hallstatt Era 800-400 BC).

Roman ruins underneath a sports shop in town.

We enter the salt mine through a tunnel dug in the 1700s, and descend to where the salt is located. The salt was deposited in layers from seawater periodically evaporating during the Mesozoic Era. The deposit is rich with iron from the seawater, giving the salt a red color. (Thanks to the guide for being so patient with all of our geology questions!)

Entrance to the salt mine.

Salt deposits in the mine.

The mine has continuously functioned through the millennia. The mining techniques adapted with technology, and today the salt is mined by being dissolved into water under pressure. The salt is then transported as brine through pipes 40 km to the town of Ebensee, where it is placed in evaporative pools to extract the salt.

The evolution of brine pipes.

An old brine pipe.

The system is so efficient that the mine only employs 28 workers total. Because of the loss of jobs in the mining industry, young people have left town for opportunities elsewhere; the population has shrunk by half, and many of the houses have become rental properties for tourists.

Hallstättersee receives wastewater discharges from the mine through one of its tributaries. On two occasions in the last few decades, the brine pipes burst leaks, releasing large amounts of brine into the lake. News reports suggested that the brine sank to the bottom immediately and therefore had no impact on the lake; we were interested in the effects of sudden intense additions salt on the benthic ecosystem. Our discussion papers found that the brine spills caused ectogenic meromixis (the lake stops mixing during “turnover” periods) and hypoxia (low or no oxygen) in the deeper regions of the lake which showed temporary die-off of benthic fauna. Even though one brine spill was much larger than the other, the lake took the same amount of time to recover from the shock by flushing the salt out of its basin (3 years, or 6 times its water residence time).

Hallstattersee

As far as we can tell, culturally and economically, though the lake is beautiful, here salt is king. The lake is lucky that it has the natural ability to respond quickly to the occasional “oops” of large brine spills, because the salt isn’t going anywhere soon.

(Posted by Victoria)
(Photos by Victoria)