Early Spring Flora of the Sub-Pannonic Steppic Grassland (NATURA 2000 Site) in Bilje, Northeast Croatia

Abstract

-The diversity of early spring vascular fl ora was studied in the Sub-Pannonic steppic grassland in the village of Bilje, north eastern Croatia. In all, 109 plant taxa within 35 families were found. The highest number of taxa belongs to the families Poaceae, Fabaceae, Asteraceae, Caryophyllaceae, Lamiaceae and Rosaceae. Specifi c habitat conditions, characterized by moderately wet and moderately acidic soil with intermediate fertility and the effects of the continental climate favour the development of different plant life forms. Out of the total recorded plant taxa, hemicryptophytes make up 59.6%, followed by therophytes (22.0%) and geophytes (13.8%). Chorological analysis shows that the most numerous are plants of Eurasian (33.9%), Pontic-Central-Asian (21.1%) and Central European (21.1%) fl oral elements. According to their status in the Red List, three critically endangered (CR), one vulnerable (VU) and three nearly threatened (NT) plant species were found. Altogether, the steppe-like grassland in Bilje is a unique habitat rich in valuable plants of the Croatian fl ora, including the critically endangered Doronicum hungaricum, therefore it is of great importance to preserve it. Important management tools include mowing and controlling the spreading of cultivated and invasive plant species.

A UAS and Machine Learning Classification Approach to Suitability Prediction of Expanding Natural Habitats for Endangered Flora Species

“…The field detection of flora units from this study indicated an increase in the population count of endangered flora species, with the number of detected flora units increasing to 129 as compared with 109 units five years prior [7]. To potentially extend their habitat to neighboring areas, we proposed a habitat suitability prediction method based on noninvasive field observations from remote sensing imaginh using a UAS multispectral camera system and machine learning classification.…”

“…The steppe in Bilje is located in the central part of a cemetery and covers an area of 0.63 ha, representing the last remnant of the steppe-like grassland in Croatia (Figure 1). There is a significant share of the xerothermic elements from the eastern European steppes, for which this study area represents a westernmost limit of distribution [7]. Research in the past thirty years has confirmed that there were more such habitats in eastern Croatia but they have mostly disappeared due to land-use transformation into arable land or overgrowing with shrubs [10].…”

“…All these conditions place additional demands on land management of protected natural areas in Croatia; under the new circumstances, a detailed inventory is required for the purpose of spatial planning [6]. The most recent study, in 2016, on the flora of the steppe-like grassland in Bilje reported a total of 109 plant species detected from 35 families [7]. The steppe-like grassland in Bilje was protected in 2001 under the category of natural monument and it represents an integral part of the ecological habitat network of the Republic of Croatia within the Natura 2000 [7].…”

“…The most recent study, in 2016, on the flora of the steppe-like grassland in Bilje reported a total of 109 plant species detected from 35 families [7]. The steppe-like grassland in Bilje was protected in 2001 under the category of natural monument and it represents an integral part of the ecological habitat network of the Republic of Croatia within the Natura 2000 [7]. Due to the human-made habitat degradation caused by suboptimal land management over the years, an initiative was started for the expansion of steppe-like grassland in Bilje.…”