Climate change may strongly modify the habitat conditions for many woody plant species. Some species could disappear from their natural habitats and become endangered, while others could adapt well to the changed environmental conditions and continue to survive successfully or even proliferate more easily. A similar process can occur within the artificial urban environment as the hitherto popularly planted urban trees may suffer from the extremities of the urban climate. However, among the planted taxa, there are species that spread spontaneously and appear as weeds in extensively managed gardens. In our study, we evaluated the native and non-native species involved in spontaneous spreading in the institutional garden of Buda Arboretum (Budapest) during the COVID-19 period in 2020–2021 when entry was prohibited, and maintenance went on in a restricted, minimal level. We investigated the correlation between spontaneously settling and planted individuals, and then performed multivariate analyses for native and non-native spreading plants for spatial and quantitative data. During our studies, we observed the spontaneous spreading of 114 woody species, of which 38 are native and 76 are non-native. Taking the total number of individuals into account, we found that, in addition to the 2653 woody species planted, a further 7087 spontaneously emerged weeds developed, which creates an additional task in the maintenance.

The world’s big cities, including Budapest, are becoming more crowded, with more and more people living in smaller and smaller spaces. There is an increasing demand for more green space and trees, with less vertical and less horizontal space. In addition, deteriorating environmental conditions are making it even more difficult for trees to grow and survive. Tree species in urban areas have multiple functions and high ecosystem services when in good health. Among taxa with diverse habits, sizes, crown shapes, growth vigor, longevity, urban tolerance, and canopy habit, our research aims to evaluate urban specimens of spherical species with smaller space requirements and sizes but have regular geometric crown shapes in public plantations in Budapest. In the restricted urban habitats, the city’s cadastral records include 4676 specimens with spherical crowns. Among the species examined, eight species with globular crowns (Acer platanoides ‘Globosum’, Catalpa bignonioides ‘Nana’, Celtis occidentalis ‘Globosa’, Fraxinus excelsior ‘Nana’, Fraxinus ornus ‘Mecsek’, Platanus × hispanica ‘Alphen’s Globe’, Prunus × eminens ‘Umbraculifera’ and Robinia pseudoacacia ‘Umbraculifera’) were evaluated in relation to age, health, wood type, crown size, and shade projection in order to show which species are or will be suitable in the future.

Field surveys are essential in the Hungarian motorway planning process so that it would be possible to assess their impacts on the landscape, since the available databases are insufficient in respect of listing all the valuable elements of the landscape. The aims of the research are to analyse the impacts of the planned M30 Motorway (located in north-eastern Hungary) on the landscape, to enumerate the cultural and natural valuable elements of the landscape near and within the area to be expropriated, to explore the possibilities of their protection and to outline the possible land use conflicts likely to arise after the implementation of the motorway. The main sources used for the research were: landscape, green space management and environmental protection studies made for the modification of the affected settlements’ urban plans, field surveys alongside the entire track, and existing environmental databases. In the case of M30 motorway, the chosen corridor was mostly acceptable in the sections where the motorway track leads along the track of the existing Main Road 3, because it is fitted to an existing linear artificial landscape element, it is basically on the border of two natural micro-regions and can also fit into the existing land use structure. Nevertheless, it is not considered to be the best choice in places where it separates vineyards from vine cellars, where it is located within 50 meters from residential areas or where it passes through small plot vineyards or horticultural areas instead of the arable lands of the nearby plain.

The purpose of this study is to evaluate the potential of restoration of a stream section. The starting point of the multiple-step assessment process was a historical analysis, which resulted in the definition of different sections within the study area, providing a base for the further restoration goals. The assessment of the current conditions was elaborated particularly to determine those factors, which could limit restoration. These assessments cover the land use pattern, furthermore the analysis of vegetation and habitat patches. As a result of the historical analysis, it has been found that the stream side habitat patches have decreased significantly despite the constant space available. This change was not caused by the increased area of the settlement, but rather by the higher dominancy of arable forms of land use. The greatest share of wet and mesic meadows and agricultural habitats in the study areas, covering 57.5% of the total area, indicates significant anthropogenic effects. Consequently it can be stated that the reference conditions are not the only determining factors of the restoration possibilities. Restoration style and intensity have been defined on basis of all assessed factors.

The aim of this study is to conclude the experiences of the maintenance practice of an artificial thermal lake. The first years (2015-2017) of the development of the lake were analysed and evaluated along the following questions: a) What kind of design processes and maintenance interventions are related to the process of fitting the lake into the landscape? b) How have the ecological conditions of the lake evolved in the past period (zonation, succession, plantation and colonization)? c) Which general experiences could be gained from the operation of this artificial thermal lake this far? The authors of the present study were already engaged in the planning process, participating in the preparation of four different design documentations. The planting design and the maintenance instructions were based on a physico-chemical monitoring, phytoplankton, zooplankton and macroinvertebrate sampling, and machrophyte assessment. The significant processes during the three years of the lake are presented by functional groups of biota, separately assessing the characteristics of the changes of macrophytes. In 2017 an individual macroinvertebrate assessment was done, moreover a fish die-off occurred in August 2017, which are mentioned separately as well. The data in total suggested that the water of the lake is highly hypertrophic, further machrophyte introduction can prevent the plant nutriments to be absorbed by algae. Partly the algal growth but also the unlucky coincidence of other factors (e.g. high water temperature, cold weather front, maintenance problems) led to the die-off of the spontaneously overpopulated fish stock in 2017.

A tájépítészet magyarországi elismertségének növeke-dése, a tájépítészeti tervezés egyre jelentősebb szerepeazzal jár, hogy a tájépítészeti növényalkalmazás, a tudato-san tervezett kiültetések, mesterséges növénytársulásokegyre erősebben képesek alakítani a hazai flóra összeté-telét és képét. Ugyanakkor az őshonos, és különösen avédett növényfajok meglehetősen csekély részaránybanjelennek meg a tájépítészeti alkotásokban, a tervezők szí-vesebben nyúlnak idegenhonos taxonokhoz. Az őshonosnövényfajok mellőzése a nagy léptékű tájépítészeti alko-tások (közparkok, ökoturisztikai létesítmények, városiszabadterek) esetében jelent különösen komoly problé-mát, hiszen ezeken a zöldfelületek mennyisége, ökoszisz-téma-szolgáltatásai és környezeti nevelési potenciálja iskiemelkedően magas.Kutatásunkban az őshonos fajok alkalmazásávalfoglalkozunk, illetve több szempontból megvizsgáljuka védett fajokkal kapcsolatos tájépítészeti lehetősége-ket. Áttekintjük a védett fajok alkalmazására vonatkozószabályozási környezetet, valamint vizsgáljuk a Magyar-országon védelem alatt álló fajok előfordulását a dísznö-vény-kereskedelemben is, azt áttekintendő, hogy a piaciszereplők valóban betartják-e a természetvédelmi jog-szabályokat. Az őshonos fajok tájépítészeti alkalmazásátkiemelten a BudaPart városrész mintáján vizsgáljuk, amintaterület kiültetéseinek fajszintű elemzésén keresztül.Mindemellett jó gyakorlatokon és megvalósult példákonkeresztül illusztráljuk, hogy milyen lehetőségek állnakrendelkezésre az őshonos és védett növényfajok alkalma-zására a tájépítészetben. Eredményeink reményeink sze-rint rávilágítanak arra, hogy különösen nagy kiterjedésű,illetve természetvédelmi szempontból kiemelten jelen-tős projektek esetében nagy szükség lenne az őshonosnövényfajok szélesebb körű alkalmazására, illetve arra,hogy fontos és időszerű lenne, hogy elkezdődjön a szak-mai párbeszéd bizonyos védett fajok ellenőrzött körülmé-nyek között történő kultúrába vonásának lehetőségeiről.