LIFE FOR SEEDS: Siberian iris on Lake Cerknica

Part of the LIFE FOR SEEDS project also involves restoring grassland habitats and preparing a proposal for a new agricultural measure from the Agri-Environmental-Climate Payments (KOPOP) intervention package. These are activities that require a good knowledge of the biology and ecology of species characteristic of the habitat being restored or the habitat we want to maintain through agri-environmental measures, as, for example, restoration activities carried out in the wrong way can cause more harm than good.

To this end, during the implementation of project activities such as habitat type mapping and the collection of seeds from wild species, which the project partners store deep-frozen in a seed bank, we also catalogued locations and researched the impact of management on plant species that we identified as bioindicators. Such species are important for nature conservation as they are an indicator of the functioning or preservation of habitats.

Some of the bioindicator species can also be considered umbrella species, as appropriate management to ensure their long-term survival also ensures favorable conditions for other species characteristic of the umbrella species' habitat. Based on its biology, the Siberian iris (Iris sibirica) can also be considered one such bioindicator species of wet grasslands and lowland marshes. It is protected in Slovenia and may not be picked or removed from nature; it is also listed on the red list of endangered species.

The Siberian iris is generally threatened by:

• the abandonment of mowing, which leads to the gradual transformation of its habitat into forest,
• the degradation and disappearance of suitable habitat due to drainage, urbanization, etc.,
• soil fertilization and the associated intensive mowing (several times a year), which favor the growth of other plant species and often impoverish the biodiversity of fertilized land,
• removal from nature for horticultural or ornamental purposes,
• regular mowing at inappropriate times, which eventually exhausts the plants to the point of extinction.

The light-loving Siberian iris blooms in late spring or early summer, but its seeds ripen only in late summer or early autumn, so mowing has a direct impact on its growth, which can be either positive or negative.

By learning about the ecological requirements and habitat of the Siberian iris in the area of the intermittent Lake Cerknica, we have deepened our knowledge of the factors threatening it and, based on the results of research into the impact of management on it (together with the results of research into Fragrant onion), we will be able to determine a management method that will enable the sustainable maintenance of its habitat and populations.

We hope and trust that our proposal for a KOPOP measure will see the light of day and be well received by landowners, as this will ensure that Siberian irises and other endangered species continue to adorn the lake meadows and that our descendants will also be able to experience the wonderful diversity of our very special piece of the world.