The paper presents the results on the study of the possible application of the Canadian Forest Fire Weather Index and the Modified Angstrom Index in forest fire risk assessments. The daily values of these indices for the period 2005-2015 were related to the forest fire database. It was found that there is a relatively weak to moderate correlation between forest fires and the values of the Canadian Forest Fire Weather Index. In order to improve the wildfire risk assessments (including forest fires), the index was modified. The modified index has a significantly greater correlation with the actual events of forest fires and consequently a much wider application in southern Serbia. The modified index can be of great importance in the future concepts of forest fire risk management.

Being a natural, ecological and renewable resource, wood is increasingly replacing artificial and toxic materials in the manufacture of various types of packaging and other products; thus, its proper and economically justified use has become necessary. The best utilization of wood raw materials has been sought both in practice and theory, which led to the development of a number of non-destructive and semi-destructive methods for the wood quality assessments in various stages of wood exploitation. In this paper, two instruments for the inspection of the internal condition of standing trees were analyzed. The resistograph was designed for the detection of internal defects. In addition to assessing the condition of living trees of different species, the instrument is used to assess the wood density in various materials. The observed resistance during drilling is proportional to the change in the wood density or the relative mass of the element analyzed. The results of drilling in different spots or directions, through the cross-section and along the element, can be used to map the properties of the element. The fractometer is a device designed to measure the strength and other mechanical properties of on a core sample extracted by using an increment borer from a certain part of the tree or branch examined. The fractometer can determine the maximum fracture force and bending and pressure strength of wood. It is also possible to identify the stage of decay. Due to its heterogeneous structure and anisotropy, the wood compressive and bending strengths differ between different anatomical directions even within a single species. The results of previous research in the literature indicate that there is a significant positive correlation between the radial bending strength and the longitudinal compressive strength of wood. This actualizes the need for the use of different tree species in construction, depending on the load that the wood element will be exposed to. These devices provide high precision and quality in measurement and can achieve a good correlation between the measured values and the mechanical properties of wood. This way, science and practice could be provided by significant data on the properties and quality of wood, while its consumption is minimized.

The vitality of a forest ecosystem to a great extent depends on the effect of different factors of stress, be it of biotic (harmful insects, phytopathogenic fungi, etc.), abiotic (frost, drought, high temperatures, etc.) or of anthropogenic origin (human activities). Some factors owning to their long-lasting effect can lead to the weakening of the individual trees or the whole forest ecosystem and eventually cause the mortality of it. The paper presents the results of the research of the types of damages of biotic, abiotic and anthropogenic origin at the sample plot of LEVEL 1 in the Republic of Serbia, conducted during 2013. By the analysis of the data, the results concerning the total number of trees with the identified types of damage, the part of the tree on which the some type of damage occurred most commonly, total number of the trees without any damage, most frequent type of damage and the types of trees with the highest and lowest percentage of damage, were obtained. The results which were obtained present the factual situation regarding the types of the damages for each sample plot and can be beneficial for the further analysis. By comparing these data with the date from other countries, the conclusions about the way in which the vitality of trees depend on the environmental conditions were made.

This chapter aims to show the phenomenon of forest fires from socioeconomic aspects to present the readers with a new perspective. We start from the assumption that fire in forest ecosystems has a positive and negative impact, which can be represented by an appropriate valuation system. The basis for such an assumption was found in the paradox of fire (in natural ecosystems), which has had human attention from the very beginning of the human population. From early views on social dependence on fire to a modern perspective, that fire is a catastrophic phenomenon in nature. Today, it can be assumed that our valuation system is set at a point where fire harms nature. This tacit acceptance has become commonplace in fire reporting where the importance of fire in removing biomass especially coniferous stands, maintaining open spaces for grazing and hunting, reducing catastrophic wildfires, in carbon balance and water regulation or scientific knowledge is almost completely omitted. Contemporary streams in nature and forest science and practice point out that fire is an ecosystem service providing many services with trade-offs between fire prevention and the provision of ecosystem services. Here, we explain why fire in natural ecosystems become relevant for science after the eighties. We present that the extent of fire damage is more than 0.012% of Worlds GDP in this decade. Major socioeconomic driving factors of forest fires are presented too. The chapter presents examples of ecosystem services and economic impacts provided by wildfires.