The impact of military activities on preserving butterfly diversity in the central Slovenian military area – Poček | Vpliv vojaških aktivnosti na ohranjanje vrstne pestrosti dnevnih metuljev na osrednjem vadišču slovenske vojske – poligon Poček

English. In 2007 and 2019, a quantitative inventory of the butterfly fauna was conducted in the central part of the Poček military training area, with the aim of comparing the fauna from both periods and evaluating the impact of military activities on the butterfly diversity. Using a standardized linear transect method and covering all habitat types represented in the military area, a total of 73 species were observed in both years (2007: 62,2019: 61), including 11 threatened species (2007: 9, 2019: 8). The fauna of both sampling periods differed significantly in composition but not in species diversity, average population density of species on single transects, and in average population density of species in the area. The difference in the faunal composition is the result of species turnover and changes in the size and spatial distribution of the population densities of the species at an individual transects. Among species whose population density decreased in 2019 compared to 2007, those with the highest densities in forest vegetation types in 2007 prevailed. On the other hand, the predominantly grassland species became more abundant in 2019. This means that regular, but temporally and spatially uneven military activities, represent heterogeneous disturbances that maintain an extremely diverse mosaic of habitat types, in which large scale extensively maintained dry calcareous grasslands and dry grasslands in the early stages of succession have the greatest conservation value. Military activities thus make an important contribution to the conservation of the biodiversity and landscape diversity of the area.

Slovenian. V letih 2007 in 2019 je bil opravljen kvantitativni popis favne dnevnih metuljev v osrednjem delu vojaškega poligona Poček sciljem primerjave stanja obeh vzorčenj ter ovrednotenja vpliva vojaških aktivnosti na pestrost favne dnevnih metuljev. S standardizirano metodo transektnega popisa na linijah, ki so vključevale vse za območje poligona reprezentativne habitatne tipe, smo v obeh letih skupaj opazili 73 vrst (2007: 62, 2019: 61), med njimi 11 ogroženih (2007: 9, 2019: 8). Favni obeh vzorčenj stase značilno razlikovali v sestavi vrst, ne pa v vrstni pestrosti, povprečni populacijski gostoti vrst na posameznem transektu in povprečni populacijski gostoti vrst na poligonu. Različnost v sestavi favne je posledica vrstnega obrata ter sprememb v velikosti in prostorski razporeditvi populacijskih gostot vrst po transektih. Med vrstami, ki se jim je populacijska gostota v 2019 zmanjšala v primerjavi z 2007 so prevladovale take, ki so imele v 2007 največje gostote v gozdnih vegetacijskih tipih; med vrstami, ki so v 2019 dosegale višje populacijske gostote kot v 2007 pa tiste, ki so bile najštevilčnejše na traviščih. To pomeni, da redne, vendar časovno in prostorsko neenakomerne vojaške aktivnosti predstavljajo heterogene motnje, ki vzdržujejo izjemno pester mozaik habitatnih tipov, v katerem imajo največjo naravovarstveno vrednost obsežni ekstenzivno vzdrževani suhi kamniti kraški travniki in suhi travniki v zgodnjih fazah zaraščanja. Vojaške aktivnosti tako pomembno prispevajo k ohranjanju biotske in krajinske pestrosti območja.