Issues

Abstract

Fragments of a scull and lower jaws of Nutria were found near river Maritsa, close to Harmanli town. There are suitable habitats for this species in the area, overgrown with reed and rush near the bank and the islands in the river. The location lies at about 50 km on a straight line from the nearest one known on river Maritsa in Turkey, and at about 35 km from another one in Bulgaria and probably results from invasion of the Nutria along the river.

Abstract

Forest quality and growth sustainability can be influenced by many risk factors throughout the development process: human activity, environmental conditions change, the effects of global warming, water and soil pollution, forest pests and diseases, proliferation, wild animal damage. Ensuring the safety and quality of forest stands of timber approach to consumers needs methods to predict and identify potential risks and determine their potential impact. Real situation calls for new studies in detecting weaknesses and errors in the control and management system for all forest development stages of the technological process. His main objective to explore the food industry HACCP systems proved their worth of applications in the private forestry with the aim to provide customers with stable and high-quality timber resources.

Abstract

The present paper presents information on the species composition, features of distribution and harmfulness of dendrotrophic pathogenic fungi, based on long-term observations on the health status and diseases in different types of urban plantings in Moscow and some towns of Moscow suburbs. The survey revealed more than 300 species of pathogenic fungi causing various diseases on roots, trunks, branches, leaves and needles in more than 70 species of coniferous and deciduous trees and shrubs, including a lot of introduced woody plants. Special attention is given to the diseases decreasing durability, protective and aesthetic functions of urban plantings.

Abstract

The aim of the present investigation was to establish the duration of work time and productivity of a mobile forest skyline Koller K 300 in Ograzhden Mountain. The length of the studied roadtrack was 270 m and the transported wood was of Common beech (Fagus sylvatica L.). The terrain investigations were carried out with 107 work courses of loaded carriage for a period of four days. Each work course was divided into nine phases. It was established that most time was used for the work phase 'Motion of the loaded carriage to the landing site' similarly to other terrain investigations. The average productivity was 3.22 m³·h^-1. The results indicate that with a proper organization the forest skyline Koller K 300 could yield very good productivity.

Abstract

The ever-growing demand for timber and restricted harvesting in oak and beech forests resulted in the idea of establishment of fast-growing forest tree plantations. The present paper presents results of a study on the plantations established in 1984 and 1985 in State Forest Service (SFS) Gorna Oryahovitsa, near the village Paisiy. The experiment consisted of pure plantations of Pseudotsuga menziesii (Mirb.) Franco, Cedrus atlantica Manetti, Quercus rubra L., Tilia tomentosa Moench., Robinia pseudoacacia L. and Pinus nigra Arn., and mixed plantations of Cedrus atlantica, Quercus rubra and Tilia tomentosa. All species were planted in three different locations. Robinia pseudoacacia plantations with initial density 2 x 1 m, and natural Quercus cerris - Q. frainetto stand were used as control. The intensive plantations were more productive than both conventional stands and natural forest. At the age of 20 to 21 the target species were in good health, grew well, and did not show any signs of deteriorating health. Highest increment was recorded in the pure plantations of Tilia tomentosa, Pseudotsuga menziesii and Pinus nigra. The research proved that intensive forest plantations are especially suitable for the lower forest belt if they are planted on suitable locations and the soil is appropriately cultivated.

Abstract

This study aims investigation of chukar partridge losses during the incubation period in species’ nesting habitat. From 45 nests set in 2010 and 2011, 19 (42.22 %) were destroyed. In 13 of these, mammal predation was the cause. 4 (8.89 %) were destroyed by birds and 2 (4.44 %) by unknown pest. Statistical differences between the size of destroyed nests and herb vegetation height have not been found. Losses were, more likely, distributed randomly in time. Relationship between setting time and herb vegetation height was not established.

Abstract

In the last decades numerous studies have presented vegetation classifications. Some of them highly subjective, relying entirely on qualitative data, others more objective, based on quantitative information, susceptible to statistical tests. On that ground, vegetation organization was viewed either as composed of recognizable community units or as a continuum with gradually changing composition, provoking continuous debate. This study represents numerical classification of forest vegetation on the south slope of Vitosha Mountain, Western Bulgaria. We hypothesized that described community types will not hold the statistical test for their consistence. Stratified sampling procedure and nested 0.1 ha sampling plots were used. Obtained field samples were classified with TWINSPAN clustering method. Resulting groups were tested for statistical difference for the most important environmental gradients and vegetation variables. 114 field samples were collected and grouped in nine forest community types. Six of them are dominated by Fagus sylvatica L. Two are coniferous forests (plantations), where Pinus nigra Arn. and Pinus sylvestris L. are most abundant. The last one is mixed oak forest. Beech forests predominate at higher elevation, in more mesic habitats and on steeper slopes. Most of the beech communities have significantly higher canopy closure and lower shrub and herb strata cover. Mixed oak forest and coniferous communities are richest in almost all life and growth forms. They are more susceptible to invasion, because of their proximity to populated areas and severe disturbance regime, therefore richer on alien species. Mixed oak forest and coniferous communities also have significantly higher species richness per 0.1 ha and 1 m², as well as higher alpha diversity and evenness. All forest communities in the studied region are poor in rare, protected and endemic species. Despite the significant differences between some of the Fagus sylvatica communities and the mixed forests, they are generally unrecognizable statistically from each other. Therefore, the vegetation of the studied area is considered as having continuum organization. Numerical classification, relying on quantitative and statistically testable data, will objectify and simplify vegetation understanding and improve future management activities.

Abstract

The proposed concept is a result of a two-year study of the components that have a direct impact on the optimal functioning of the resort. Object of the study were the following main components: spaces activity, isochron accessibility, functional zoning, scheme of mobile and pedestrian communications, structure of plant volumes. The aim of the study is to overcome some disparities connected with the existing commercial activities, administrative and municipal services, particularly as regards the methodology of selecting the site and offering of attractions. Certain basic and secondary plant volumes, which form the spatial skeleton of the complex and contribute to its harmonious integration into the surrounding landscape, are defined. Parameters are referred to for further improvement of the green system in the territory. The maintenance and development of this trend will set the resort of 'Albena' as an area with high ecological factor. The concept includes ideas for reconstruction of: continuation of the axis from the main entrance of the complex as an organized attraction area; promenade with a proposal for a centrally situated park space in the middle of it; 'Air lane' over the proposed park space for a link between the beach and the upper part of the complex; walking trails with viewing sites located on the same part. The established regularities and the proposed solutions contribute to the achievement of a modern and appropriate spatial structure of the complex with an improved combination of the social environmental factors with the existing natural landscape elements.

Abstract

The trees & bush vegetation in the 'Albena' resort can be viewed in two main groups, namely: I. Main plant capacities: local plant volumes; scaffolds-forming plant volumes; II. Secondary plant capacities: landscaping of the surrounding area of the buildings according to individual projects; plant collections and exhibitions. This analysis defi nes relationships and outlines guidance for the future development of the complex. The work is clarifying the structural connections between different types of plantation, the particular public parts of the complex and their functional capacity.

Abstract

The map of erosion has been drawn on the basis of black-and-white aerial photographs. Seven categories of terrain were differentiated according to land cover type and the areas subjected to erosion. Map interpretation included an analysis of the impact of the main relief characteristics (inclination, altitude and exposure) together with human activity upon the state of the studied terrains. This state was judged by the index of erosion. The impact of inclination has been found to be multi-aspect, depending on exposure. The latter, compared with the rest of the relief characteristics, predetermined erosion to the greatest extent. We confi rmed the decisive impact of anthropogenic activity.

Abstract

Several methods for overcoming wild cherry seed dormancy have been studied. Wild cherry (Prunus avium L.) seeds have shown to be affected by combined dormancy: weak morphological and deep physiological dormancy. Fresh stones responded differently to the various methods for dormancy breaking. The study showed that the dormancy of fresh seeds is successfully overcome by sowing the seeds immediately after their harvest or in autumn. Stored seeds, however, did not have a positive response to these specific sowing periods. Acceptable germination rates were achieved after application of seed stratification. Findings showed that accelerated stratifications did not give positive results for successful dormancy break in the conditions of Bulgaria. Stored seeds should be sown in spring after application of combined warm and cold stratifications with the following durations: 6 weeks of warm period and 5 months of cold period.

Abstract

In this paper features of container 'œPaperpot', 'œYucosad', 'œPirosad' and bare root seedlings, used in afforestation in the R. of Macedonia, are presented. Morphometrical features of seedlings were measured and statistically compared. A further development of Austrian black pine trees in stands and in experimental fields, raised from container and bare root seedlings in different ecological conditions was investigated. Height and diameter of trees were measured, and their vitality was estimated. Container type and its volume do not directly influence the seedlings quality. All investigated container seedlings have more or less satisfying features, independently on container. Survival, development and vitality of young stands depends more on site conditions and planting techniques; the influence of container type is not expressive. Survival and vitality of younger stands is quite poor. Trees in older stands develop more or less normally, influenced mostly by site conditions. There is not crucial influence of container type on development and vitality of stands recorded.

Abstract

In the past, Portugal was an important producer and exporter of crude resin (pine oleoresin) obtained from living trees. The main species used as a source of Portuguese naval stores until today is Pinus pinaster Ait., one of the most productive resin species. With the increase of labour costs in the forest, the international market competition from China and Brazil and the occurrence of severe forest fires, the importance of both resin yield and industry has sharply diminished. Despite of the decrease of Pinus pinaster area in last decades, this species still holds an important position in Portuguese forest - 885,019 ha, according to the last National Forest Inventory (NFI). In European Union (EU), Portugal remains one of the few countries with the capacity to supply and fulfil the special needs of some industries: for instance turpentine for perfumery and rosin for the manufacturing of tyres. In the present paper we estimated the potential yield capacity of the Portuguese maritime pine forest based on the NFI data, and made a summarized SWOT analysis, having in mind the weaknesses and the virtues of the remaining resin economic sector.

Abstract

There are a number of problems within the temporarily inaccessible and hardly accessible forest exploitation basins, as the lack of a road network, lack of information about how many inaccessible basins are there, where are they located and what kind of a road network should be necessary for their exploitation. The present paper deals with the state of the inaccessible and hardly accessible forest exploitation basins in the Eastern Bulgaria (total 53) situated on the territory of the Regional Forestry Directorates (RFD) of Varna, Shumen, Sliven, and Burgas. The draft-traces of the new forest roads that should be constructed within the forest basins. The road locations have been adjusted and different variants of technological schemes, appropriate for the different working conditions and types of cutting were proposed. The total area and the resource, as well as the provided uses have been determined. The expenses required for logging have been calculated, as well as the expenses for road construction. The expected incomes, outcomes, and the prime costs of the wood planned for harvesting were calculated as well. The mountainous orography and the low density of the forest-road network within the basins provided opportunity for a choice between two types of machines to be used (a specialized tractor and a short cable systems), or a combination of both.