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The state of bio-ecological characteristics of the one-year shoots of Robinia pseudoacacia L. Under the conditions of industrial pollution

Abstract

The paper studies the influence of industrial pollution on bio-ecological characteristics of the one-year shoot of Robinia pseudoacacia L. in the conditions of the city of Dnipro, Ukraine. It analyses the state of biometric parameters of the shoot and anatomic indices of the stem of the studied species exposed to toxic gases. It was found that there are adaptive changes in the histological structure of the stem of R. pseudoacacia under the conditions of technogenesis. The study revealed that bio-ecological characteristics of the black locust are highly resistant to industrial emissions with big shares of SO2 and NO2. It was suggested to use R. pseudoacacia for greening of the technogenic territories.

Open access
Suitability of MODIS-based NDVI index for forest monitoring and its seasonal applications in Central Europe

Abstract

The paper demonstrates the multipurpose application of the normalized difference vegetation index (NDVI) derived from MODIS products for forest monitoring across the Central-European macro-region Slovakia and Hungary (i.e., the Western Carpathians and Pannonian basin). Relationships between forest dynamics and NDVI were analysed and used for determining the onset of phenophases in spring and autumn and for the assessment of forest growth and health condition. To identify the phenophases, the NDVI profile during the year was established by fitting a double logistic sigmoid function to data and phenological metrics were developed based on the calculated extreme values of the sigmoid function and its derivatives. According to our analyses, leaf unfolding and leaf fall were significantly delayed or advanced in 2018 with the increase of altitude and latitude (p < 0.01). The longitudinal aspect was significant only in the autumn phenophase with earlier onset of leaf fall towards to the east. The duration of the growing season varied extensively within the region, mainly according to altitudinal and latitudinal occurrence of beech forests. Positive associations between annual tree-ring width and standardized summer NDVI were found for conifers at local scale. The highest correlation period was between July 12 and August 12 as the most critical periods for forest growth. Slight positive correlation can be observed during March – April that could be associated with the varying start of the growing seasons. In the forest health study, whereas NDVI values could well identify the location and extent of a recent forest damage due to a combination of snow break and wind break, an urgent demand for more detailed field data was obvious.

Open access
Sysmä Community Currency: An Analysis of its Success from the Perspectives of Purposes, Stakeholders and Promotion

Abstract

The article is a case study of a local currency, recently introduced in the rurally situated municipality of Sysmä, Finland. As a small community suffering a gradual population decline since the 1960s, Sysmä municipality has begun to innovate with several projects this millennium. Here, we analyse as a narrative and from the viewpoint of experienced tensions, the introductory phase of one of these projects, which strictly is a hyper-local currency acting as a system of account. It is noted that there are unclarities regarding the purpose of the scheme, and that different stakeholders and other observers do have varying ideas about this purpose. Political decisions over limiting rights of issuance of the local currency to locally registered businesses; and its exclusive use for local association subsidies have created some challenges to the acceptance of the currency. Further, the currency has limited uptake due to technical issues, injudicious use of the marketing mix and difficulties with innovating in a rural area. Noting these issues and the peculiarity of the scheme amidst other typical European local currency schemes, the article also points out benefits of the scheme and potential future developments.

Open access
A Ten-Year Biomonitoring Study of Atmospheric Deposition of Trace Elements at the Territory of the Republic of Belarus

Abstract

For the third time since 2005 atmospheric deposition of trace elements in Belarus was monitored by the moss technique widely used in Europe for air pollution studies. Samples of moss species of Hylocomium splendens and Pleurozium schreberi were collected at 86 sites over the Gomel, Vitebsk and Minsk Regions in the summer of 2015. A total of 30 elements were determined by epithermal neutron activation analysis. Studying of the temporal trends in Belarus was undertaken with the results obtained in previous moss surveys in 2005/2006 and 2010/2011. Comparison with the analogous data from the neighbouring countries showed relatively low contamination levels in Belarus for the most heavy and toxic elements. The results of survey 2010/2011 showed that, except Cr, other element concentrations reduce or are at the same levels.

Open access
Trophic characteristics of Lymnaea stagnalis (Mollusca: Gastropoda: Lymnaeidae) in toxic environment

Abstract

The influence of ions of heavy metals (copper, cadmium, nickel, zinc, cobalt and manganese) was investigated on the basis of trophic characteristics: the average daily ration (ADR), and duration of food passage (DFP) of the Lymnaea stagnalis L. in various concentrations of toxicants in vivisection experiment. In addition to these indicators, the total amount of food consumed in the solutions with various concentrations of pollutants was found out during the chronic experiment and it was calculated for an individual (average monthly ration – AMR). It leads to the conclusions about the intensity of food consuming considering different levels of intoxication. In solutions with lethal concentrations, the death of animals occurs during the first day of its impact due to the damage of tissues and organ systems. Chronic lethal concentrations of toxicants inhibit the nutrition of pond snails dramatically. At the beginning of the experiment, solutions of heavy metals with sublethal concentrations give some stimulatory effect on the digestive system of molluscs that is replaced by its suppression in case of longer being in the toxic environment. The influence of toxicants within a subthreshold limit cannot be considered safe because of the cumulative properties of heavy metals – they become sublethal with prolonged exposure time.

Open access
Utricularia vulgaris L. and Salvinia natans (L.) All. heavy metal (Fe, Mn, Cu, Zn and Pb) bioaccumulation specificity in the area of Bardača fishpond

Abstract

Paper deals with seasonal changes in heavy metal bioaccumulation (Fe, Mn, Cu, Zn and Pb) in Utricularia vulgaris L. and Salvinia natans (L.) All. of two localities (Necik and Sinjak – active fishpond basins) in the area of Bardača fishpond. According to our results, the better accumulator of Fe (3035 mg/kg) and Zn was S. natans (163.55 mg/kg), whereas Utricularia vulgaris better accumulates Mn (620 mg/kg) and Cu (10.18 mg/kg). Amounts of Pb in both investigated macrophyte were below the detection level (<0.51 mg/kg). The values of the bioaccumulation factor (BAC) of the tested metals were >1 or ~1 for both species, and the BAC values decreased in the following order in both investigated species: Fe > Mn > Cu > Zn. The results obtained indicated that tested macrophyte show very good characteristics as bioaccumulators and, thanks to this fact, they could be used in phytoremediation technique successfully in water-polluted ecosystem.

Open access
The vertical accuracy of digital terrain models derived from the close-range photogrammetry point cloud using different methods of interpolation and resolutions

Abstract

Structure-from-motion (SfM) in combination with multi-view stereo (MVS) represent techniques, which allow efficient generation of the point cloud from close-range photogrammetry (CRP) images of forest ground. Recent software products for the generation of digital terrain models (DTM) includes a wide range of interpolation methods. Previous studies showed different errors in elevations of DTMs interpolated with different methods. This study aims to analyze differences between the elevations of DTMs derived from CRP point cloud using different methods of interpolation. Six methods of interpolation included in modular system OPALS were tested in the study. In addition to simple methods of interpolation such as Snap or Moving average, more complex methods were used for interpolation of the DTMs elevations. For each method, 5 DTMs with resolution ranging from 1 to 20 cm were generated. Elevations of the DTMs were compared with the elevations of Global Navigation Satellite System (GNSS) surveyed check points. RMSE of DTMs elevations ranges from 3.4 cm to 16.2 cm. Differences between the elevations of DTMs interpolated using different methods and resolution were further investigated using one-way analysis of variance (ANOVA). The ANOVA rejected the statistical significance of the differences. Additionally, the spatial distribution of errors was analyzed. The analysis indicates that the interpolation of the extreme DTM values can be expected at the edges of the DTM when using the CRP images captured from single passing through the study site.

Open access
Young urban trees as important structures in the cultural heritage of cities – a case study from Prague

Abstract

Urban trees generate numerous ecosystem services, and these are often closely associated with the species, age and size of trees as well as with their vitality. Generally, the focus of urban and regional planning is aimed at very large trees, because very large trees are considered to be key green structures in an urban green infrastructure. However, there is a significant knowledge gap related to the importance of young trees in cities, despite their value in urban green spaces, greenways, parks, gardens, urban forests, and as components of green roofs and green walls. This study is the result of field mapping young trees in the urban area of the famous European historical city of Prague. Field mapping revealed a total of 40 individual young trees, or young tree groups, with cultural value in the study area of Prague. The results of this empirical study indicate that young trees (not just very large and old trees) can be very important structures for the provision of cultural ecosystem services in cities, and that they can be viewed as living cultural symbols. This is a new aspect in the awareness of the environmental and social roles of urban trees. This case study from Prague suggests that (i) young trees in urban areas need more attention from researchers and (ii) should be incorporated into urban planning as an important component of urban green infrastructure.

Open access
Effect of Agripreneurship on Employment and Income Generation in Cattle Fattening Business in Nigeria

Abstract

Unemployment is a major issue in Nigeria because the youth finds it difficult or impossible to secure jobs that meet their expectations. There appears to be a mismatch between graduate skills and those sought by employers. The study investigated the effect of International Institute of Tropical Agriculture (IITA) youth Agripreneurs (IYA) programme on employment and income generation on cattle fattening enterprise under the N2Africa Borno youth project. A two-stage sampling procedure was used to select IYA participants and non-participants. Results revealed that the majority of respondents were males in both categories. It also indicated that youths who are in their productive age are more into cattle fattening enterprise in both categories. The study also found that, unemployment and skill acquisition are the main driving reasons for participating in IYA. It also indicated that both categories of respondents’ required external capital support for start-up of their enterprise, and that IYA programme participants on the average earn more income per month than non-participants. IYA programme participants generated more employment opportunities which implied that the programme had not only empowered participants but also made the participants’ become employers. The study recommended that there is a need to support youths with funds, access to trainings on capacity development and skill acquisition to make them self-employed and job creators.

Open access
Food Safety Challenges in the Tourism Processes

Abstract

The modern food industry is among the key partners of today’s global tourism. As part of the tourism processes, tourists buy and consume local food in the local catering facilities. Furthermore, tourists are usually willing to try out gastronomy specialties during their travels. Food safety is important for tourists although it is not always part of their conscious behavior in the destination. Food safety standards are regulated by international contracts based on the analysis of more half a century’s experiences. Within processes related to the changes in the external environment, there are emerging issues – although in different intensity - like chemical and microbiological contamination or food terrorism. Due to the immense number of participants in tourism, it is of key importance to raise awareness of threats like food decay, infections and other negative impacts, because food safety if a basic need in all tourism destinations. The amount of waste food is increasing dramatically at a global scale. The study will introduce the findings of a food safety research in Hungary, providing useful knowledge to all stakeholders of the tourism industry.

Open access