Issues

Using Remote Sensing and GIS technologies as an aid for creating database for the dendrarium in the Training and Experimental Forest Range "Petrohan" is the focus of discussion in the paper. The cardinal study goal is illustrating a concrete instance of applying GIS technology in the landscape architecture survey. This paper describes the methodology of vegetation mapping using traditional method combined with remote sensing data. Creating graphical and attribute table databases is also useful in the education of students in the University of Forestry in Sofia. Making semester projects in academic discipline Dendrology the students have to learn and analyze the features of trees and shrubs. GIS software provides the capability to analyze large data sets containing features of coniferous and deciduous trees and shrubs in the dendrarium. In the other hand the purpose of the development of the vegetation mapping methodology is to provide an objective and cost-effective survey method utilizing satellite remote sensing for the vegetation mapping. Overall, these results confirm that satellite imagery data coupled with field observations and direct measurements can be used effectively for precise mapping of trees and shrubs. The result of the analysis shows that image objects extracted from satellite data provide a new opportunity to make detailed inventory maps of ornamental vegetation in parks. In such cases, it is imperative that such exploration technologies should be used, which are cost effective and provide greater accuracy. An integrated approach of remote sensing and GIS technologies can just suffice these requirements during exploratory efforts in difficult terrains.

Visual impact of forest landscapes is the focus of discussion in the paper. Their influence on passengers and onlookers sidelong roadways and trails is described in detail. A great number of practical examples have been examined with the purpose of drawing some general conclusions from this problem to the advantage of landscape design practice. The result of the analysis shows different degree of landscape damages visual impact over the observers. Using color photographs and taxation indices for the same forest stands the survey concludes that from the standpoint of aesthetics or recreation value forest products such as scenic beauty can be assessed either with psychophysical measurement procedures or with taxation indices of the forest subdivisions. Two such procedures are compared for convergence. The methods gave similar results with respect to their theoretical foundations and their independently derived scenic beauty metrics. It is hoped that the comparison of these procedures will facilitate needed discussion on their appropriateness and usefulness in multiple use forest management and planning efforts.

Distance measurements feature an inextricable section of applied forestry science from the Forester engineer and concern a great variety of technical procedures. In nowadays the technological explosion of surveying instruments make these measurements a matter of seconds and even faster. Also, new alternative measurements are considered, such as reflectorless measurements, a function that is offered by most geodetic total stations. The range and accuracy of this function type is different and depends on the type of the total station. However, not sufficient attention has been given to the many error sources contributing to the uncertainty of such measurements and especially the quality of each measurement. Among others, the type and the colour of the material are considered as very important parameters for errors in distance measurements. The aim of this study is to determine the influence of the type of the material and colour to the quality of distance measurements using the total stations reflectorless ability. Therefore, experiments were carried out using 8 different types of materials or colours and Trimble 5605DR+ long range total station.

The paper presents a classification of 1010 species, belonging to 296 genera and 84 families of wild melliferous plants. A particular attention is given to the characteristics of the conservational importance of these plants at national and international level. Two hundred and one of these species belonging to 71 genera and 36 families were considered to have some conservational status in Bulgaria and Europe. Many of them are endemics for Bulgaria and/or Balkan Peninsula and are protected by the national Bulgarian legislation or by international conventions ratified by Bulgaria. The results indicate that substantial part of melliferous plant species of the Bulgarian flora is of high conservation value.