The unknown natural habitat of Rosalia alpina (L.) (Coleoptera: Cerambycidae) and its trophic association with the mountain elm Ulmus glabra in Poland - a change of habitat and host plant
A unique natural habitat of Rosalia alpina (L.) located in the Beskid Niski mountain range (Carpathians) and consisting of a forest clearing community in the stage of succession with the mountain elm Ulmus glabra, in part dying and dead, is described. Results of the laboratory rearing of this longhorn beetle from elm wood as well as field observations of its adults in this natural habitat are given. This habitat and trophic association of R. alpina with U. glabra are discussed in connection with the known trophic relations of this insect species with host plants of the genus Ulmus.
The yew gall midge Taxomyia taxi has been found for the first time in the Polish Carpathians. The site lies in the “Yews in Mogilno” (“Cisy w Mogilnie”) nature reserve in the western part of the Beskid Niski (Low Beskid) Mountains. The species occurs over an area of ca. 37 ha, mostly in the northern, lowest-lying parts of the reserve. 19.4% of the inspected specimens of the European yew were found to exhibit signs of feeding by gall midges. Most of the infested yews (86.7%) were barren, 8.2% were females and 5.1% males. The yew gall midges displayed no clear preferences in relation to the health status of the host plants, although yews with a healthier photosynthetic apparatus were selected more often.
Effects of ungulate pressure on the development of young generation of trees is one of the most important issues in ecology and forestry. Ungulate pressure influence on the development of natural regeneration has been also reported from several national parks. Our study on the effects of ungulate browsing on the young generation of trees was conducted on more than 500 sample plots controlled during one growing season.
The overall browsing pressure ranged from 7.6% in seedlings to 20.3% in low saplings. The pressure of ungulates on the regeneration of Picea abies, the dominant species in the Tatra National Park, was by and large below 1%. Broadleaved species were browsed more frequently. The relationship between the plot altitudes and browsing intensity was statistically significant for seedlings and low saplings; at the higher altitudes, the browsing pressure was greater. There was also observed a statistically significant relationship between the type of former management and the browsing degree in seedlings; in the areas subjected to “landscape protection”, the intensity of browsing was higher when compared to strictly protected areas. Pressure exerted by ungulates on tree regeneration was very unevenly distributed, i.e. some plots were heavily browsed and many others - not browsed at all. The most affected tree species were Salix caprea and Sorbus aucuparia, although the percentage of browsed individuals rarely exceeded 50%. Other species favored by ungulates was Acer pseudoplatanus; despite the high browsing pressure, this species was present among seedlings and tall saplings, suggesting that it would be able to recruit to the tree layer. Abies alba was browsed less frequently than the deciduous trees; however, among the tall saplings it was the third most browsed species.
The composition and structure of forest stands in the Tatra National Park were examined using data gathered in 2016 and 2017 from 617 circular sample plots (0.05 ha each). The diameter at breast height of all living trees, standing dead trees, snags, and wind throws was measured along with diameters and lengths of fallen logs within the plot boundaries. Tree height was measured for all living trees within the core (0.01 ha) of the sample plots. Using the obtained data, height-diameter curves were calculated for all major tree species and in the case of spruce, the height-diameter relationships were also calculated separately for each of the three elevation zones (up to 1200 m, between 1200 and 1400 m, above 1400 m). For each elevation zone and park protection zone, we also determined the volumes of live and dead trees. The volume of living trees in the Tatra National Park amounted to 259 m3/ha, which was higher than the volume of dead trees (176 m3/ha). Snags constituted the largest part of the dead wood whilst over 97% of the standing dead trees were spruce Picea abies. Among living trees, the share of spruce ranged from 81% in the low elevation zone to 98% in the middle zone. Other significant species in the lower zone were Abies alba (11%) and Fagus sylvatica (4.5%), while in the middle and upper elevation zones only Sorbus aucuparia occurred in significant numbers. Furthermore, in the lower elevation zone, Fagus sylvatica was the only species displaying significantly higher volumes in the ‘strict protection’ zone compared to the other park areas. In the ‘landscape protection’ zone, Picea abies was the most dominant species and the share of other species in the lowest elevation zones calculated based on tree density was smaller than calculated based on tree volume, indicating problems with stand conversion from spruce monoculture to mixed forest.
In 2012 the development of the rosalia longicorn Rosalia alpina (L.) was confirmed in the sycamore maple Acer pseudoplatanus L., a new host plant in Poland. In the laboratory, one adult beetle was reared from a branch obtained from the Magura National Park (Beskid Niski Mts., Carpathians, SE Poland). The breeding material was collected at a site located in the fertile Carpathian beech forest association Dentario glandulosae-Fagetum, in a stand with an admixture of sycamore maple trees. In the paper the importance of the sycamore maple as a host plant is discussed.
The primary objective of this study was to characterise the edaphic conditions of forest areas in the Pieniny National Park (PNP), and to describe the dependencies between properties of forest soils and types of forest plant communities. The “Soil Trophic Index” (SIGg) for mountainous areas was applied. The evaluation of the trophism for 74 forest monitoring employed the soil trophic index for mountainous areas SIGg or SIGgo. Plant communities in the forest monitoring areas were classified according to the Braun-Blanquet’s phytosociological method. Soils of PNP present in the forest monitoring areas were mostly classified as eutrophic brown soils (72.9%), rendzinas (10.8%), brown rendzinas (5.41%), and rubble initial soils (5.41%). Pararendzinas, dystrophic brown soils, and gley soils were less common (total below 5.5%). In the forest monitoring areas of PNP, eutrophic soils predominate over mesotrophic soils. High SIGg index of the soils is caused by high values of acidity and nitrogen content. The Carpathian beech forest Dentario glandulosae-Fagetum and thermophilic beech forest Carici albae-Fagetum associations are characterised by high naturalness and compatibility of theoretical habitats. The soils of the Carpathian fir forest Dentario glandulosae-Fagetum abietetosum subcommunity is characterised by a higher share of silt and clay particles and lower acidity as compared to the Carpathian beech forest Dentario glandulosae-Fagetum typicum subcommunity. The soils of the forest monitoring areas in PNP stand out in terms of their fertility against forest soils in other mountainous areas in Poland.