Zheko Radev

Tobacco and tobacco products institute, 4108 Markovo, Bulgaria. E-mail: zhekoradev@abv.bg

Proteins are one of the main components of honey bee-collected pollen. In present days pollen is of great interest as food supplement. The objective of this research was to determine theprotein content of pollen in some floral species in semi-mountain area and to analyse the lengthof life of bees fed on different protein content in the pollen. The analysis of 30 samples showedthat bee pollen was described by a content of protein, which depends on the botanical origin ofbee-collected pollen. The percentage of the total protein content in the bee pollen grains rangedfrom 14.83 % for Helianthus annuus L. to 26.14 % for that of Prunus cerasifera Ehrh., and the average value was 20.90 %. In this research Rosaceae floral species had the highest levels ofprotein content of all studied representatives. The impact of the protein food on the length of lifeof worker bees was found. The average lifespan of worker bees fed on pollen from P. Cerasiferawas 24.74 days, whereas it was 16.92 days for the worker bees fed on pollen from H. annuus.Lifespan of honey bees consumed pollen with higher protein content is prolonged compared tothose that consumed pollen with lower protein content.

Kateryna Myronchuk(1)*, Yaroslav Henyk(2), and Marta Kurnytska(2)

1. Yuriy Fedkovych Chernivtsi National University, 2 Kotsyubynskoho Str., 58012 Chernivtsi,
Ukraine. *E-mail: k.myronchuk@chnu.edu.ua
2. Ukrainian National Forestry University, 103 Gen. Chuprinka Str., 79057 Lviv, Ukraine.

Object of the study are hedgerows in settlements of Ukrainian Bukovynian Carpathian region (Chernivtsi region of Ukraine). The species and quality composition, spatial, age and ecological structure and ornamental value of hedges. The formation of hedges as an element of landscaping the urban ecosystems of the Ukrainian Bukovynian Carpathian region occurred due to the influence of a number of objective (natural and anthropogenic) and subjective factors (traditions, socio-economic conditions and long-term plans for the development of the region, financing of activities for the formation and care of plantings in green spaces). The dendroflora of hedges of urban areas is represented by 32 species of woody plants from 24 genera and 15 families. Carpinus betulus L., Buxus sempervirens L., Cornus alba (L.) Opiz. and Ligustrum vulgare L. are most often used to form hedges. The vast majority of hedges is formed from one species (Chernivtsi – 98.3 %, other towns and villages – 71.1 %), and they are mainly single-row (Chernivtsi – 83.8 %, other towns – 58.2 %, villages – 70.2 %). In the settlements of the region, trimmed hedges predominate (Chernivtsi – 92.1 %, other towns and villages – 75.5 %). Most hedges are mean-height hedges (Chernivtsi – 65.8 %, other towns and villages – 66.9 %). For the formation of a curb hedge, Sріraea media Schmidt., Buxus sempervirens, Ligustrum vulgare are most often used. For first time, comprehensive studies of hedges in the settlements of Chernivtsi region of Ukraine (Bukovynian Carpathian region) were carried out according to their species composition, system, age and environmental structure, height and constitution. The features of functioning in urban ecosystems are established. A comprehensive assessment was made regarding the quality status and ornamental value of hedges in the green zones.

Volodymyr Maliuha(1), Vasyl Khryk(2), Viktoriiа Minder(3), Ivan Kimeіchuk(1,2), Maksym Raduchych(4), Andrii Rasenchuk(1), Fedir Brovko(1), and Vasyl Yukhnovskyi(1)*

1. Department of Forests Restoration and Meliorations, Forest Institute, National University of Life and Environmental Sciences of Ukraine, Kyiv. *E-mail: yukhnov@ukr.net

2. Department of Forestry, Bila Tserkva National Agrarian University, Ukraine, Bila Tserkva

3. Department of Landscape Architecture and Phytodesign, Forest Institute, National University of  Life and Environmental Sciences of Ukraine, Kyiv.

4. State Enterprise ‘Ovruch Forestry’, Zytomyr regional management of Forestry, Ukraine.

The fractional composition of forest litter was studied in pure and mixed plantations with a pre dominance of Scots pine aged 14–85 years. The study was conducted in anti-erosion plantations of ravine-gully systems of Dnieper Upland, in parks on Kyiv slopes of Dnieper River, Ovruch Ridge, as well as in the plains of Kyiv and Zhytomyr Polissia. Forest litter is with a thickness of 2.2–2.5 cm in mixed stands and 2.5–3.5 cm in pure stands with a stock of 20.8 and 27.8 t·ha-1, respectively. The mass of litterfall in the studied areas is different and ranges from 2.9 t·ha-1 in mixed planta  1 tions to 14.1 t·ha-1 in pure pine ones. Analysis of the fractional composition of litter showed that its -1 active part (leaves, crumbs, fruits) in all experimental areas is in the range from 65 to 82 %, while the inactive part (branches, bark, cones) is 18–45 % of the total mass. The active part in mixed plantations is 73–82 %, pure ones – 65–67 %, and the inactive part is 18–27 and 34–45 %, respectively. The rate of destruction and mineralization of freshly dead phytomass was determined by analysis of litterfall-litter index – the ratio of litter mass to the mass of annual litterfall. Plantations of ravine-gully systems are characterized by strongly inhibited intensity of litter mineralization with an index of 6.2–7.9. The index ranges from 2.9 to 4.5 in park plantations and from 1.1 to 5.5 in the plantations of the plain sites. The mass of water absorbed by litter is 11.0–50.8 t·ha-1 and its moisture capacity is in the range of 134–319 %, which is equivalent to 1.6–4.8 mm of precipitation.

Salomo Mbai(1), Epson Ndawedapo Noses(1), and Yonas Tesfamariam Bahta(2)*

1. Namibia University of Science and Technology, Department of Agriculture and Natural
Resources Science, Windhoek, Namibia. E-mails: smbai@nust.na; epsonmoses@gmail.com

2. University of the Free State, Department of Agricultural Economics, Bleoemfontiem 9300,
South Africa. *E-mail: Bahtay@ufs.ac.za

Analysing and understanding the timber sector export performance is essential for value chain role players to formulate strategies and policies to enhance the competitive export position and ensure forest sustainability. This study’s main objective was to measure the export competitiveness of the Namibian timber (HS440799, HS4401, HS4402, and HS4403) and assess its implication for Forestry using secondary data (2001–2018), Revealed Comparative Advantage (RCA), and Revealed Symmetric Comparative Advantage indices (RSCA). The result shows that Namibia had a revealed comparative advantage for 17 years; however, all below one (except for commodity HS4402 from 2010–2018) means that Namibia timber exports are not internationally competitive. Comparing the four categories of timber, in 2007, the sub-sector (HS4402) recorded the lowest RCA (0.00001) and the lowest RSCA (0.99998) for timber (HS4402) in 2007, the same year. On the other hand, the same categories of timber (HS4402) score the highest RCA with a value of 2.73 in 2015 and the highest RSCA (0.46) for timber (HS4402) in the same year compared to the other categories of timber. RSCA indices results for all commodities show that Namibia’s timber exports are not competitive for the study period. Timber’s comparative export pattern heavily depends on export volumes and values of timber exports. Timber export competitiveness is not sustainable, given the heavy dependence on natural forests. Namibia should re-structure timber harvesting protocols to include replacement or replanting every tree species harvested for timber production to ensure timber and forest sustainability. The country’s timber export sub-sector should focus more on adding value to timber than exporting to improved competitiveness. Further, the government should regulate the harvested wood and protect over-grazing, to promote timber and forest resources’ sustainable utilization.
 

Zheko Radev

Tobacco and tobacco products institute, 4108 Markovo, Bulgaria. E-mail: zhekoradev@abv.bg

In the research, HPLC method was used to determine the composition of sugar profile of identified honey bee-pollen from Asteraceae species spread in a forestry area. The analysis showed that bee-pollen is described by a high content of glucose and fructose, which depends on the origin of bee-collected pollen. They constitute from 60.0 % of the total sugar content for Centaurea cyanus L. to 100 % for Carduus sp., Centaurea sp., Centaurea calcitrapa L., Сentaurea solstitialis L. and Chondrilla juncea L. bee-pollen. The content of fructose ranged from 13.3 % for C. juncea to 20.3 % for C. calcitrapa, average 16.8 %. Glucose was the second highest content from 10.2 % for Echinops ritro L. to 21.4 % for C. cyanus, average 15.5 %. Of all analyzed samples the presence of trisaccharide melezitose was not detected.