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  • Author: Peter Uhrin x
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Abstract

Climate conditions in cities are constantly changing, creating a worsening environment for the growth of trees and performing their ecological functions. Qualitative evaluation of their responses to the often extreme climatic conditions and habitat for their growth is an important part of care for urban and historical greenery. This work deals with applying visual methods for the assessment of morphological characters, crown destructive manifestations and eco-physiological aspects of vitality through micromarker of quality of assimilation organs. Evaluation was carried out in two types of environment, in city of Nitra and an environmentally unloaded historical park in Nová Ves nad Žitavou. The research was conducted on six trees of species Acer pseudoplatanus L., through visual assessment and measuring the values of chlorophyll fluorescence-a. The measurement results were statistically evaluated and graphically interpreted.

Abstract

Adaptability of Acer platanoides L. to deteriorating urban conditions was assessed through qualitative parameters describing crown destruction, assimilation organs efficiency, chlorophyll a content, and content of alochtonous elements in leaves. The adaptability assessment was based on comparison between study trees growing in an environmentally loaded town area and control trees in a historical rural park, both localities in Slovakia (Central Europe). The results of visual assessments performed in 2015 and 2016 showed higher crown and leaf quality (Qns) for the individuals growing in the rural park (Qns 2015 = 0.44, Qns 2016 = 0.43) compared to the individuals in urban conditions (Qns 2015 = 1.44, Qns 2016 = 1.56). The values of chlorophyll a content index (CCI) were higher in the trees growing in the rural park (CCI = 25.914) than in the urban environment (CCI = 16.290). The performance of assimilation organs was evaluated through the maximum fluorescence yield (Fv/Fm) and electron transport rate (ETR) at both sites. During the years 2015 and 2016, there were measured higher values in the rural park (Fv/Fm 2015 = 0.828, Fv/Fm 2016 = 0.820) than in the town (Fv/Fm 2015 = 0.823, Fv/Fm 2016 = 0.772). Higher ETR values were measured on trees in the urban area (ETR 2015 = 47.345, ETR 2016 = 65.284) and lower in the park area (ETR 2015 = 36.832, ETR 2016 = 59.495). The urban locality demonstrated higher contents of Cu, Zn, Fe, Pb, Na and Ca elements in tree leaves compared to the rural park. The adaptability index (Ia) values indicate an average adaptability of the Norway maple to the urban environment (Ia 2015 = 1.93, Ia 2016 = 2.13) in comparison with a good adaptability in the rural park (Ia = 0.8–1.6).

Abstract

Until now, late summer or autumn invasions into inhabited building have been regarded as phenomenon typical for the common pipistrelle, pipistrellus pipistrellus, exclusively. During the investigation of this phenomenon in the city of Košice (eastern Slovakia), we discovered that it was not always entirely specific for this species. During the period 2016–2018, we recorded 3 events out of 35 invasions, where small groups of common pipistrelles that invaded into inhabited buildings were also accompanied by individuals of two con-generic bat species, pipistrellus pygmaeus and pipistrellus kuhlii. Cryptic species p. pipistrellus and p. pygmaeus were determined by genetic test. In addition, in 2019, we recorded the first winter occurrence of another pipistrelle species, pipistrellus nathusii, in this urban environment. We conclude that areas of frequent invasive behaviour of p. pipistrellus may be sometimes associated with concomitant occurrence of other related species that share common thermal or foraging niche and such behaviour could be evidence of their urbanisation tendencies.

Abstract

Urbanised landscape represents composed structures of technical and biotic elements where social and economy activities create living space for human society but with strongly changed environment. To dominant characters belong climate changes with increased air temperature, drought and emission load, which has developed wide spectrum of stress factors influencing the urban vegetation. For the assessment of plant growth and adaptation response, we have used Sycamore maple (Acer pseudoplatanus L.) as study model woody plant. In the framework of visual characters, we assessed the following indicators: (a) assimilation organs (leaf necrosis); (b) crown quality (degree of foliage and degree of dead tree crown); (c) trunk and branch quality (mechanical damage, incidence of wood destroying fungus and trunk cavities and callus healing of trunk wounds). Each indicator was assessed in five-point scale, and in the end, the common index of quality was calculated. The quality index achieved 9.33 points in the first and 10.33 in the second evaluation periods in the Nitra city and 2.66 at the both assessed periods in the comparable rural park. In the group of physiological indicators, chlorophyll a fluorescence marker and its Fv/Fm parameter were used. Within three repeating assessment during growing season (June, August and September), the average values reached Fv/Fm = 0.814 in the city and Fv/Fm = 0.829 in rural park. The results confirmed statistical significances between loaded city conditions and relatively clean rural locality. Used markers have shown as appropriate tools for growth response measurements of street trees in a changed urban environment.