László Bank, László Haraszthy, Adrienn Horváth and Győző F. Horváth
In this study, the results of a long-term nest box installation program of the Common Barn-owl Tyto alba (Scopoli, 1769) in Southern Hungary were evaluated, which program was conducted during a 24-year period (1995–2018). The percentages of occupied nest boxes ranged from 9.72 to 73.44% in the first breeding periods while this varied between 0 and 41.46% in the case of repeated clutches in the same nest boxes with second broods. A total of 1,265 breeding attempts were recorded including 1,020 (80.63%) in the first and 245 (19.36%) in the second breeding periods, from which a total of 210 (16.6%) clutches did not produce any fledglings. The modal clutch size was 7 eggs in both first and second annual clutches. However, the value of productivity was higher in the case of larger clutch sizes and we found significant linear relationship between initial clutch size and fledgling production per nesting attempt in both breeding periods. Significant variation of reproductive parameters was observed among the years. The proportion of egg loss showed significant decline, while the change of hatching success and the variation of annual productivity showed significant slight positive linear trend during the 24 years. Our results suggested that despite the outlier values of reproduction characteristics in the extreme years with negative effect, a relatively stable Common Barn-owl population can be maintained by the placement of nest boxes in the investigated region.
Adrienn Horváth, Anita Morvai and Győző F. Horváth
This study investigated the dietary niche of the Barn Owl (Tyto alba) in an intensively farmed landscape, based on pellet samples from 12 nesting pairs containing 25 animal taxa and 1,994 prey items after the breeding season in 2016. Based on land use categories of the buffer area around each nest, three landscape types (agricultural, mosaic, urban) were considered, to analyse the diet composition and food-niche parameters. Niche breadth was calculated at the local and landscape level. Small mammals were the most frequent in the diet than other prey in each of the landscape types. The Common Vole (Microtus arvalis), considered to be an important agricultural pest was the most numerous prey in all landscape groups. The trophic niche of Barn Owl varied between 0.69 – 0.86 at the local level, and the overall value of niche breadth was significantly higher in the urban than in the other two landscape types. Our results showed that the increase of Common Vole frequency lead to a decrease in niche breadth; significantly negative relationship was detected between these parameters. Despite differences in niche breadth, similarly high niche overlaps were detected by the randomisation test in the three landscapes. Our results suggest that the diet composition of Barn Owls, mainly their food-niche pattern, reflected prey availability in the comparison of the studied landscapes, which pointed out that it is necessary to examine the dietary difference of Barn Owls at the finer scale of land use.
András Polgár, Adrienn Horváth, Katalin Szakálosné Mátyás, Attila László Horváth, János Rumpf and Andrea Vágvölgyi
Almost half of the total area of Hungary is arable land. Nearly one-third of this area is poor-quality arable land where agriculture would be uneconomical. Energy plantations can be grown extremely well on poor-quality land. Currently, the carbon neutrality of wood as a raw material must also be justified, considering several factors. Environmental life cycle assessment (LCA) was developed as a tool for sustainable, decision-supporting, environmental management, which is an outstanding tool for the well-established analysis of environmental impacts, although the application of it in forestry remained a challenge for the LCA community. No sector specific LCA and life cycle inventory methodology has been developed in forestry; thus, implementing such a methodology remains a big challenge. Calculated on a common functional unit (100 m3/ha wood chips, 100% energy purpose), we have performed a comparative environmental life cycle assessment for harvesting technologies of short rotation energy plantations (technology related to stands of 3 ha of poplar, 5–10 ha of willow, 20 ha of willow), specifically for the third year harvesting work system. Research results on global warming potential show the carbon footprint of harvesting work systems, the knowledge of which has a strong influence on the environmental consideration of raw material (wood chips) and also on the more precise definition of carbon sequestration capacity. The typical values of carbon balance ratio (1.37–1.46) indicate a positive carbon sequestration potential and a magnitude well within the system boundaries of the third year harvesting work system submodule. The results obtained enable the estimation and prediction of environmental impacts for the whole lifecycle of the plantation.