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We produced the first spatially explicit, cross-border, digital map of long-term (160 years) land use in the Carpathian Ecoregion, the Hungarian part of the Pannonian plains and the historical region of Moravia in the Czech Republic. We mapped land use in a regular 2 × 2 km point grid. Our dataset comprises of 91,310 points covering 365,240 km 2 in seven countries (Czechia,

Location, spread, abundance and density of forest regeneration are key factors in understanding forest dynamics as well as in operational management of uneven-aged stands. Simulation of forest growth, silviculture and planning of skid road networks require accurate and objective methods for locating forest regeneration. Terrestrial laser scanning has high potential for tree mapping, however, the development of automatic processing methods has been focused on mature trees so far. This study introduces an automatic procedure to locate individual trees with 3-6 meter height from terrestrial laser scanner data. The method has been validated on three sample quadrates representing different stand structures and it succeeded in detecting 79-90% of trees extracted manually from the point cloud. Out of the investigated stand features, stem density had the strongest impact on the performance, while branching intensity slightly affected the detection rate. The results highlight that terrestrial laser scanning has the ability for the quantitative evaluation of regeneration, providing a prospective tool for surveying forests of contiguous cover.

Sporobolus vaginifl orus, a "for a long time expected" invasive alien of North American origin has now reached Hungary. Th e fi rst stands were recorded in 2015 in SW Hungary on the motorway M70 near Letenye; its occurrence was already foreseen in view of its expansion along the roads of Croatia and Slovenia. Similarly to other aliens (e.g. Senecio inaequidens, Plantago coronopus) arriving from the Adriatic direction on the newly constructed motorways the authors reckon with its further rapid expansion in Hungary.

Th e fi rst part of the newly launched series includes miscellaneous new records from fungi to vascular plants. New Th e present paper includes also the revision of the occurrence of Calamag rostis villosa in Hungary and concludes that it has been extinct in the country.

Abstract:Proper knowledge about resources in forest management is fundamental. One of the most important parameters of forests is their size or spatial extension. By determining the area of treefall gaps inside the compartments, a more accurate yield can be calculated and the scheduling of forestry operations could be planned better. Several field-and remote sensing-based approaches are in use for mapping but they provide only static measurements at high cost. The Earth Observation satellite mission Sentinel-2 was put in orbit as part of the Copernicus programme. With the 10-m resolution bands, it is possible to observe small-scale forestry operations like treefall gaps. The spatial extension of these gaps is often less than 200 m 2 , thus their detection can only be done on sub-pixel level. Due to the higher temporal resolution of Sentinel-2, multiple observations are available in a year; therefore, a time series evaluation is possible. The modelling of illumination can increase the accuracy of classification in mountainous areas. The method was tested on three deciduous forest sites in the Börzsöny Mountains in Hungary. The area evaluation produced less than 10% overestimation with the best possible solutions on the sites. The presented work shows a low-cost method for mapping treefall gaps which delivers annual information about the gap area in a deciduous forest.

This paper presents a fully automatic method addressing tree mapping and parameter extraction (tree position, stem diameter at breast height, stem curve, and tree height) from terrestrial laser scans in forest inventories. The algorithm is designed to detect trees of various sizes and architectures, produce smooth yet accurate stem curves, and achieve tree height estimates in multi-layered stands, all without employing constraints on the shape of the crown. The algorithm also aims to balance estimation accuracy and computational complexity. The method’s tree detection combines voxel operations and stem surface filtering based on scanning point density. Stem diameters are obtained by creating individual taper models, while tree heights are estimated from the segmentation of tree crowns in the voxel-space. Twenty-four sample plots representing diverse forest structures in the south boreal region of Finland have been assessed from single- and multiple terrestrial laser scans. The mean percentages of completeness in stem detection over all stand complexity categories are 50.9% and 68.5% from single and multiple scans, respectively, while the mean root mean square error (RMSE) of the stem curve estimates ranges from ±1.7 to ±2.3 cm, all of which demonstrates the robustness of the algorithm. Efforts were made to accurately locate tree tops by segmenting individual crowns. Nevertheless, with a mean bias of −2.9 m from single scans and −1.3 m from multiple scans, the algorithm proved conservative in tree height estimates.