Reducing CO2 emissions from land: Restoring wetlands or drainage systems?

Restoration works in Saessaare bog.
Restoration works in Saessaare bog. Source: RMK

The carbon footprint of Estonia's drained landscapes is comparable to that of our whole transport industry. Nevertheless, Estonian forestry and agriculture today are mainly dependent on drainage systems built over the past century. Restoring peatlands and reconstructing drainage systems is difficult to reconcile, experts say.

In recent months, a great deal of commentary has been published on the topic of land use. In a public plea submitted to the government on October 12, 11 timber industry umbrella organizations said that if Estonia met all of its goals in the land use and forestry sectors, it would result in the loss of 14,000 jobs and a decrease of 2.5 percent in GDP.

The tensions between land use and greening are particularly evident in the restoration of wetland areas while also reconstructing clogged drainage systems.

Scientists and conservationists have been working on major restoration efforts in Estonia's peatlands for over a decade. In other words, previously excavated ditches have been filled in to restore the area's natural water collection. The goal was to restore habitats and, in the long run, to slow climate change.

Drained peat soils emit about 1.4 million metric tons of carbon dioxide annually, whereas the peat layer of a true wetland could stores carbon dioxide very well.

Conservationist Indrek Tammekand helped restore wetlands at the Kikepera nature reserve in Pärnu County by filling in drainage ditches.

"When this draining was done, it was thought that large forests could grow here, increasing our wood supply. We can now see that 50 years of drainage had little effect on forestry needs. Instead, the ecosystem's natural potential that could aid also in climate change mitigation has vanished," Tammekänd said.

Wetland restoration now is primarily limited to nature reserves, at the same time as drainage ditches in commercial forests and agricultural land are rapidly located and restored.

Rüütli bog in Alutaguse National Park, Ida-Viru County. Source: Rene Kundla/ERR

Although no new drainage systems are being build today, Estonia still has about 1.4 million hectares of registered land reclamation area, with 750,000 hectares located on forested and 640,000 on agricultural land.

However, the actual extent of drainage systems in Estonia may be even greater as many locations are not unregistered.

The impact of drying techniques is clear from the reduction of Estonia's wetlands. It was once a textbook fact that 22 percent of Estonia's land was wetlands. In reality this percentage is significantly lower; just about seven percent of the land still functions as wetlands in ecological terms, Jüri-Ott Salm, the head of the wetland project at the Estonian Fund for Nature (ELF), said.

Although wetland restoration has been underway in Estonia for more than a decade, the scale of the restoration remains "non-existent" in comparison to the scale of drainage systems, Salm continued.

Even though no new drainage systems are being constructed at present, the effects of the ditches excavated in the past are enormous, he said.

"We have really reached a tipping point if we now need to restore even protected areas in order to preserve their natural mechanisms. The task at hand is to regain that natural balance there," Salm said.

Jüri-Ott Salm, Estonian Fund for Nature (ELF). Source: "Osoon"

"Some bad choices were made during the Soviet era: drainage systems were set up in places where there was really no point in making them -- where cultivating the land produced little income," said Tiiu Valdmaa, the head of the department of land management and land use at the Estonian Agriculture and Food Board (PTA).

Quick fixes have already been exhausted

Anti Rallmann, an expert in land conservation and the head of the department at Metsatervenduse OÜ (Estonian forest recovery association), develops and implements ways to prevent environmental damage caused by excessive land use during the repair of a ditch in Valga County's Uniküla area.

Where ditches tend to clog, sedimentation basins are being build to lessen the need for maintenance, he explained. Without periodic cleanings, natural habitat in ditches can develop faster, making them more self-sufficient and limiting the amount of minerals and nutrients that are carried away with the water.

Anti Rallmann, Metsatervenduse OÜ. Source: "Osoon"

When it comes to emissions caused by excessive drainage practices, there are few good solutions, he said.

"In fact, simple solutions have been exhausted by now, and from this point on it becomes extremely difficult."

Estonian forestry, he continued, has already taken big steps towards becoming climate-friendly. "RMK is carrying out large-scale restoration of wetlands, we have to leave standing trees in the forests and we are no longer restoring all the land reclamation [drainage] systems. The massive wetland of Soomaa, which was drained in the 1980s, but where access was difficult and the increase in forest growth was so modest that it was easier to abandon it and close the ditches, is an example of such a easy way out."

Rallmann said, however, that things are not so straightforward: closing ditches in wrong places, also along the Õru stream, can have disastrous consequences and seeking to backtrack forest drying techniques in general has very real repercussions.

Moreover, the drainage of peatland soils has a significant impact on agriculture as well as forestry.

Valdmaa also confirmed that officials are under pressure to reduce land drainage: "As officials, we need to issue permits [for restoring of existing drainage systems]. However, reconstruction projects today must be very thorough and sustainable, taking into account the need to purify water and preserve biodiversity, so that when systems are restored, living organisms and the natural ecosystems are taken in account as well." 

However, she said, agricultural use of land inevitably entails CO2 emissions to a greater or lesser degree, and this is where the land use could be in conflict with climate goals.

Tiiu Valdmaa, Estonian Agriculture and Food Board (PTA). Source: "Osoon"

While greening and land usage can be reconciled, she continued, it depends on how skillfully it is done; there are many choice points.

"It would be much better if we had specific goals for the amount of agricultural land needed to feed our population. Alternatively, if we intend to buy food elsewhere, we should have a forest to generate the funds. /.../ If our limitations were precisely known, it could happen that we manage to conserve nature and restore bogs on one side of the road, while rebuild the forest drying systems on the other," Valdmaa said.

Jüri-Ott Salm of the Estonian Wildlife Fund agreed that important decisions must be taken soon.

"It is curious that money for both restoring peatlands and reconstructing drainage systems, or even agriculture, which is drainage-based and has very high climatic impacts on peat soils, actually comes from taxpayers. In this regard, land usage in Estonia and the European Union as a whole is highly inconsistent."


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Editor: Kristina Kersa

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