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  • Author: Zigmantas Gudžinskas x
  • Plant Science x
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Abstract

Conservation of endangered plant species requires a thorough knowledge about the present state of their populations and habitats as well as identification of current and potential threats. The aim of this research was to evaluate current distribution, state of habitats and the size of populations of Equisetum telmateia (Equisetaceae) in Lithuania as well as to reveal the main threats and requirement for the conservation of this species. Analysis of all available information revealed that E. telmateia currently occurs in seven localities in Lithuania, mainly in the southern part of the country. One formerly recorded population in the south-western part of Lithuania has become extinct. Two reported localities in the environs of Druskininkai (southern Lithuania) are doubtful, because the reports have been based on misidentified specimens. Locality of E. telmateia in the western part of the country probably has been provided erroneously and one locality in the south-eastern region of Lithuania should be verified and the identity of the species requires confirmation. Total area occupied by the stands of E. telmateia in Lithuania is 2.41 ha. Most frequently this species grows in river valleys or close to rivers and occupies alluvial forest habitats, which frequently creates complexes with habitats of mineral-rich springs or springs with tufa formations. Occasionally it grows in the habitats of forests of slopes, tall herb fringe communities and hay meadows. Sporulation of E. telmateia in Lithuania is poor: no fertile shoots were registered in two studied populations, whereas in other localities few fertile shoots were recorded. Evaluation of the status of E. telmateia in Lithuania applying the IUCN criteria resulted in its categorization as a vulnerable species. The main threats for E. telmateia are forest logging and changes in habitat hydrological regime, though wild animals, human activities and invasive plant species also have certain negative impact on the populations of this species.

Abstract

Sendžikaitė J., Pakalnis R., Gudžinskas Z., 2013: Changes in botanical diversity of sown grasslands due to naturalization and extensive management [Sėtų pievų botaninės įvairovės kaitos dėl žolynų natūralėjimo ir ekstensyvaus naudojimo]. - Bot. Lith., 19(2): 99-110 The paper deals with sown grassland naturalization models related to changes in botanical diversity of extensively managed meadows under temperate climate conditions. The vegetation surveys were carried out in Sėliškės and Polyma Experimental Field Stations (Lithuania). Based on our research data and literature sources (on the investigation of Lithuanian natural meadows), we developed the following hypothetical models of sown grassland naturalization: vascular plant species constancy alteration chronocline, vascular plant species constancy and productivity alteration topocline and a scheme of sown grassland naturalization on hilly landscape. Here we consider extensive management and naturalization as one of most natural and requiring minor investments method for grassland restoration.

Abstract

Liparis loeselii is a declining orchid species in almost all European countries, mostly because of habitat loss. Therefore, good knowledge about the species ecology, distribution and populations is required in order to substantiate measures for its conservation. The aim of this research was to evaluate all available information about distribution, habitat types and population sizes of L. loeselii in Lithuania, in order to reveal the current state of our knowledge and identify information gaps. The study was based on the analysis of herbarium specimens and information in publications and various databases (a total of 481 unique records were used: 118 from herbaria, 121 from literature and 242 from databases). Intensive accumulation of information about L. loeselii started in the second half of the 20th century and a particularly large number of records were made in the period from 2010 to 2015 during the implementation of inventory and mapping of EU Habitats all over Lithuania. A summary of all information about L. loeselii revealed that it was registered in a total of 93 grid squares, and is mainly confined to uplands. The available information is quite sufficient for the evaluation of the species distribution and prevailing habitats, but is incomplete for the evaluation of population sizes, demographic structures and population trends under changing habitat conditions. Additional investigations are, therefore, required to enable a more accurate assessment of the size and viability of the L. loeselii metapopulation in Lithuania.

Abstract

Assessment of the conservation status of a species, first, should be based on its clearly defined taxonomic identity. Insufficient knowledge of certain taxonomic groups may lead to misidentifications, misinterpretations and become an obstacle for conservation. Mentha longifolia, listed as a protected plant species of Lithuania since 1981, belongs to a taxonomically complex group of species. The aim of this research was to examine available herbarium specimens of M. longifolia and verify their identification, specify distribution of this species in Lithuania and evaluate its conservation status in the country. The study was based on the analysis of herbarium specimens and information provided in references and databases. We studied a total of 93 specimens initially identified as M. longifolia. Morphological features of 30 leaves (leaf length, leaf width, petiole length, distance from leaf base to the widest place, length of leaf tooth) of both M. longifolia and M. ×villosa were measured on herbarium specimens. After the revision of herbarium specimens, we revealed that 37.6% of specimens initially identified as M. longifolia belong to other species (mostly to M. ×villosa) and 29.0% of specimens cannot be identified precisely because of the early stage of development. Only 33.4% of M. longifolia specimens were identified precisely. Thus, M. longifolia, previously supposed as quite widespread in Lithuania, after the revision appeared to be restricted mainly to the southern and south-eastern parts of the country. Applying the IUCN criteria, M. longifolia was evaluated as data deficient (DD) species. Analysis of leaf morphological traits revealed that M. longifolia and M. ×villosa can be differentiated by the length and the width of leaf blade, the distance from leaf base to the widest part of leaf and by the ratio between the length and the width of middle cauline leaves. This study revealed that taxonomic revision of the genus Mentha in Lithuania is required. Distribution of species, ecology and state of populations, impact of alien species on native congeners should be estimated in the future.