Pikaajalised muutused Eesti taimestikus ja floora kaitseks sobivad looduskaitsemeetmed.

Increased human influence causes loss of habitats of plant species and changes in species distribution. Combining changes in species distributions and abundance with their functional traits enables to evaluate species of which habitats are most endangered and to recommend appropriate measures for conservation. This study addressed the decline in species distributions and corresponding conservation measures on three levels: the whole country, one habitat type and the species level. Analysis of the changes in distribution of all species of terrestrial habitats in Estonia revealed that the persistence of flora of different habitat types varies and the persistence of species depends on species characteristics related to habitat preference and distribution. For example the distribution species of mires has declined more than that of species of forests and grasslands; distribution of habitat specialists has declined more than that of habitat generalists etc. The results show on one hand the negative effect of increased human influence on species distribution and on the other hand the decline caused by cessation of management of semi-natural habitats. Results of the analysis of the occurrence of declining species of alluvial meadows highlight the importance of preserving the habitat quality, especially the moisture regime, for the conservation of declining species of alluvial meadows. However, the occurrence of declining species is not simply predictable from the site characteristics and for protection of declining species species-specific conservation measures may be needed. Assessment of the effectivity of reinforcement of one declining plant species (Ligularia sibirica) showed, that it is effective only if the habitat quality for this species is preserved or restored. As the reproductive potential and genetic diversity in smaller populations of this species are lower, the use of only the local genetic material for reinforcement may not be sufficiently effective. The results also revealed the complex effect of interspecific interactions to reinforcement and reproduction of Ligularia, the neighbouring plants offering shelter and protection on the one hand and causing the mortality of juvenile plants on the other hand. The results show, that the decline of species at different scales is caused by different reasons, which have to be determined for applying appropriate conservation measures.Üha suurenev inimmõju põhjustab taimeliikide kasvukohtade kadu ja muutuseid liikide levikus. Liikide leviku ja arvukuse muutuste sidumine liikide funktsionaalsete tunnustega võimaldab hinnata, milliste kasvukohtade liigid on enam ohustatud ning soovitada sobilikke looduskaitsemeetmeid. Antud töö uuriski liikide levikut ja looduskaitsemeetmeid kolmes erinevas mastaabis: terve Eesti taimestik, ühe kasvukohatüübi taimestik ja ühe liigi tase. Eestis maismaaelupaikade taimede levikus toimunud muutuste analüüs (võrreldes Eesti taimede levikuatlase infot aastatest 2004 ja 1970) näitas, et floora püsimine on erinevates kasvukohatüüpides erinev ning liikide leviku püsimine sõltub liikide kasvukohaeelistust ja levikut iseloomustavatest tunnustest. Nii näiteks on soode liikide levik Eestis vähenenud rohkem kui metsade ja niitude liikide levik, samuti on enam vähenenud elupaigaspetsialistide levik. Toimunud muutused liikide levikus näitavad ühelt poolt inimmõju suurenemise negatiivset mõju (kuivendamine, eutrofeerumine) kui ka selle puudumise ehk pärandkoosluste hooldamata jätmise mõju. Väheneva levikuga liikide esinemise analüüs ühes konkreetses kasvukohatüübis, lamminiitudel, näitas, et vähenevate liikide säilitamiseks on oluline kasvukoha kvaliteedi (eriti niiskustingimuste) säilitamine. Samas pole vähenevate liikide esinemine taimestiku koosseisu järgi lihtsasti ennustatav ning taolised liigid võivad säilitamiseks vajada täiendavaid kaitsemeetmeid nagu näiteks tugiasustamine. Uurides ühe väheneva taimeliigi, hariliku kobarpea, tugiasustamise efektiivsust, selgus et see on edukas ainult juhul, kui kasvukoha kvaliteet on sobiv ning kuna väga väikestes populatsioonides on taimede paljunemisedukus ning geneetiline mitmekesisus väiksemad, siis ei pruugi kohaliku geneetilise materjali kasutamine populatsiooni elujõudu piisavalt suurendada. Analüüs tõi esile ka liikidevaheliste suhete keeruka mõju kobarpea paljunemisele ja tugiasustamisele. Ühelt poolt tingib naabertaimede hajus konkurents suure juveniilsete kobarpea taimede suremuse, kuid teisalt pakuvad naabertaimed kobarpeale kaitset üleujutuste ja loomkahjustuste eest. Tulemused näitavad, et liikide vähenemist erinevates mastaapides põhjustavad erinevad põhjused, mille väljaselgitamine on eelduseks sobivate looduskaitsemeetmete rakendamiseks

Wooded meadows of Estonia: conservation efforts for agricultural landscape

We provide an overview of the amount and ecological condition of wooded meadows throughout Estonia after significant changes in agriculture in the second part of 20th century. We also present the first attempt to estimate the success of recent conservation efforts for wooded meadows. Our analysis is based on recent exhaustive inventories. We found that Estonia, despite a decrease of the area in wooded meadows by two orders of magnitude during the 20th century, still has about 8400 ha remaining of which approximately 5800 ha are meadows with, at the least, an intermediate conservation value. The latter is directly dependent on mowing regime. Efforts to preserve wooded meadows include establishment of protected areas and financial support for mowing. The national conservation subsidy has been useful and supportive for wooded meadows, however the total amount of this subsidy has been small compared to the area that could be supported. The much larger funds of agri-environmental subsidies have largely not been available for wooded meadows. Moreover, there has been no record keeping about subsidisation of semi-natural grasslands using agricultural support schemes. Although the preservation of some good examples of wooded meadows in Estonia seems guaranteed, further degradation of this valuable habitat type on a national scale is very probable.vo