Environmental improvement works started in Razna Lake

The Nature Protection Administration (Administration) project for restoration of habitats and species habitats in Razna Lake has started to reduce the lake coastal overgrowth with canes and to find the best solutions for strengthening the erosion affected banks.

Razna Lake is a natural pearl of the Razna National Park, whose uniqueness is determined by its landscape attractiveness, the large variety of fish and birds, whose lifestyle is associated with waters. In recent years, the Razna Lake has been affected by visible changes – the shallow part of the water is growing with dense cane stands, once the sandy shore turns into a slant, while there has been increased erosion in several coastal stages, and the shore is intensively washed during the lake's waves.

The kidneys and other aquatic plants die each year, their mass accumulated in the shallow coastal part of the lake. Over time, a thick layer of sludge is formed from this mass, which starts to transform into a swamp in separate places. Access to the open water of the lake is difficult in such places, but the change in lake contributes to the disappearance of the biological, landscape and recreational (recreational) values of the site. To restore the sandy coastal areas, it is necessary to keep the kidneys on a regular basis, collect their root weaves and the accumulated sludge layer.

The reconstruction project of habitats and species in several coastal areas of the lake has already launched cane mowing works this year to form free corridors without water, which would contribute to the waves of lake and the absence of naturally-maintained shallow areas. The works are already started on the eastern bank of the lake at Strodi, where the mass of dead cane and cane root has been collected in the long zone of several dozen meters without water. “This is one of the most technologically challenging places, because the dead plant layer is even half-metre thick, the brush has begun to grow and the coast has already been swamped,” reveals project manager Inga Hoņavko.

The lake research and preparatory work have already been carried out in 2021. In the light of the recommendations of the experts, for the next two years, the aquatic plants will be used in a fragmentary and progressive manner. A total of 35 ha of pruning stands at the Strods, at the Tiles horn, around Zosna, along with the Ginewich and the Dvarcs, will be used during the project. Special conditions for the rearing of Razna lake cane are laid down in a large rebellion. There is an uncovered cane bottle, forming four islands (~ 20 x 20 m) per ha; a cane edge bordering open water is left at least 30 m wide and not more than 50 % of the total cane area per year. In view of the conditions for the protection of birds and fish, biotechnical measures in Razna lakes are carried out within a relatively short period of time, from 1 July to 30 September.

In addition to the harvesting of water plants and the removal of sludge, the project also provides for the strengthening of the lake shore in the critical stages of the Razna Lake – the coast of Tiles and the shore at Lipuški, where the lake approached the regional road Malta-Kaunata, as well as the eastern bank of the lake at the Veresovka graves. Only natural materials will be used to strengthen the shore: the anchorages will be made from arable stones, taking into account historically maximum levels of lake water. This year, the development and harmonisation of the shore-building project is taking place, the construction of anchorages will be carried out in 2023.

The overall budget of the project habitat and habitat restoration or “management measures in specially protected natural areas and micro-reserves for improvement of the conservation status of habitats and species” (No. 5.4.3.0/20/I/001) is planned to ~ 3.5 million EURO, 85% of which is financed by the European Union Cohesion Fund. Time of implementation of the project: from 2021 to 2023.

More information:
Inga Hoņavko,
Project Manager
inga.honavko@daba.gov.lv
Phone: 28607129