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Forest resources are the most significant natural resources of the state of Latvia. According to the second stage data of Forest Resource Monitoring, in 2014, Latvia has 3575 thousand hectares of forest land, which accounts for approximately 55.3 percent of the total territory of Latvia, while the total wood stock is estimated at 668 million cubic meters. A considerable part of it can be used for energy production, thus practically providing most of the necessary heat energy, a large part of the amount of electric...

The broadleave tree species have always been in the focus of attention of forest managers and owners because of valuable wood. Moreover, the presence of broadleaves increases the forest biological diversity. There is only a limited selection of tree species in Latvia ? the Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karsten), silver birch (Betula pendula Roth), pubescent birch (Betula pubescens Ehrh.), black alder (Alnus glutinosa (L.) Gaertn.), less represented - common ash (Fraxinus excelsi...

The research investigates the relation between the magnetic field deviations and the forest stand volume. The object of the experiment for the study of wood stock and related quantities was selected on the basis of the magnetic field deviations map. The Ogre Magnetic Field Anomaly Region has been selected for the research. The magnetic anomalies (magnetic field deviations) data were created digitally: a full polygon layer with values, vectorial data were obtained by adding the measurement data of the magnetic fiel...

An up to date forest inventory is the key precondition for a sustainable forest usage. Especially for owners of smaller forests, the inventory is a major cost factor, as they do not generate huge revenues from their forestry units but still have to pay the forest surveyor. One result of this situation is, that many owners do not use the timber in their forests and the timber volume, which is available for the industry, is significantly lower than it should be. The solution is a cost-efficient inventory, which can ...

This paper explores the opportunities of using Geographic Information Systems (GIS) and data from unmanned aerial vehicles (UAVs) and satellites for effective tree health mapping and assessment of forest stands, damaged from biotic and abiotic factors. The aim is to detect affected areas with tree health problems using time series satellite images. The next step is to extract precise vector and attribute data describing the type and extent of damages using drone-captured digital images. The experimental area is pa...

In the current forest typology?s scheme of Latvia the descriptions of vegetation are based on corresponding forest type?s ground vegetation in maturity stand. However, in practical forest management it is important to know forest ground vegetation?s development through all foresty cycle and valuate phytocoenoses state in every stand?s age and development?s stage. There are significant changes in ground vegetation?s taxonomic structure, projective covering and vertical structure in all forest types from clearing ti...

The research on the growth dynamics for private forest area during the last 10 years, silvicultural parameters of afforested areas and related utilization of European Union funding for this purpose, basically covers the analysis of changes in the total forest area owned by private forest owners since 2007 and the quality analysis of afforested areas. The measure for afforestation consistently affordable from the Latvian Rural Development Programme, has made a significant contribution to the total increase in the p...

Picea abies (L.) H. Karst is the most economically significant coniferous species in Europe. In central Europe, it has been growing for a long time. Since spruce stands in Latvia occupy considerable area - 18% of the total forest area (3.01 million), it is important to evaluate the impact of thinning on the productivity of young forest stands. In order to grow up healthy and productive forest stand, it is necessary thinning to perform timely and with a good quality. The aim of the research - to assess impact of Pi...

The basic rationale for the research was the lack of landscape planning approaches within the spatial planning process in Croatia. The most important deficiency addressed in this research was an integral inclusion of the public opinion and their values into the planning process. Dealing with the conflicts which may arise from it represents one of the activities that are taken into account within landscape planning. Shortage of an integrated approach to landscape planning in Croatia causes conflicts between differe...

In Latvia, English oak Quercus robur L. planting material is grown both as bare-root seedlings and bare-root plants. Its breeding is difficult, because the quality of planting material is affected by both abiotic and biotic factors. Damage caused by various factors may be spread evenly and unevenly in the area of cultivating planting material. The most common damage to seedlings and plants can be observed already in the spring, when new leaves begin to flourish and new shoots develop. It is clear that differences ...

The felling of trees on small plots, using the method of varying intensity is used in areas where widespread small-leaved Linden or she prevails.. This tree species is very closely related to beekeeping and a valuable timber.. Therefore, the proposed felling allow to organize complex mixed forests. In the spatial location they will be placed is uneven with a dominance of small-leaved Linden. Thus, in the generated uneven-age, i.e. the mosaic of forest tiers, will increase the production of nectar. This occurs due ...

Scots pine (Pinus sylvestris L.) stands are regenerated by planting, and only small portion (c.a. 13%) by self-seeding in Latvia. Seeds for plant production are collected only in seed orchards ? thus represent the results of tree breeding. Aim of our study was to assess the growth and damages as determined by forest type and genetics in Scots pine stands at the age of first commercial thinning. Tree parameters were measured in Scots pine open-pollinated progeny trials on mineral soils, differing by fertility (poor...

Population densities of cervids (moose, red deer, roe deer) are increasing sharply and consistently in Latvia since middle of 1990th, causing more damages in young forest stands. It is a result of changes in farming practices well as game-management strategies by hunting clubs. Many hunting clubs tend to keep or increase the population densities of cervids with different methods, including supplemental feeding. The aim of the study is to evaluate the impact of the proximity of supplemental feeding sites on browsin...

Cyclonic wind storms will become increasingly more common in Europe, impacting the financial values of forests due to increasing risk as well as forest composition. Aim of our study was to characterize the impact of such a storm and post-storm regeneration in hemiboreal forests, Latvia, using data from State forests service and Latvian State Forests. Forest massive with notable influence of the storm of 2005 was selected ? in it altogether 2573 ha, i.e. 13.7% from the forest area was damaged. In most of the affect...

The paper gives comparative analysis of the method of vacuum extraction of Chaga carried out by the authors. The process supposed that the ground Chaga was pre-vacuumed for 10 minutes in order to release the holes from air and moisture vapor and conduce efficient time pregnation of the extractant; further, the author saddled still dewatering the ratio 1:10 and kept at the temperature of 70В°C.In the process of extraction, the pressure was hourly lowered to 0.3 atm, which promoted the boiling of the extractant in a...

Estimating the growth level per unit of hectare and the level of production of wooded areas for accurate obtaining and portfolio is significant in determining the supply of wood for an efficient management system. The present paper is based on the evaluation of six growth seasons locust tree (Robinia pseudoacacia). The monitored sectors are located in the eastern part of the Romania. The climatic gradient can also be neglected due to the nature of the studied areas. The timeframe in which the study was conducted r...

The aim of the study is to characterise the provenances of lodgepole pine ? a potential alternative to Scots pine in sandy soils ? and to recommend the most suitable ones for establishment of plantations in hemiboreal forests in Latvia. To achieve it, data on tree parameters (height, breast height diameter, quality traits, damage by cervids) from provenances originating from North America (53?-61?N, 118?-135?W) were collected in trial in central part of Latvia. The data were processed employing parametric methods....

The purpose of the present paper is to identify the main national documents regarding the protection of forest and vinicultural plantations, with a focus places on references including the remission of effects caused by climatic changes. Romania has adopted numerous laws concerning the effects caused by climatic changes, such as Law number 251 from 28 October 2015 for accepting the Doha Amendment from the Kyoto Protocol at the United Nation?s Framework Convention regarding climatic changes; Law number 57 from 10th...

This article is devoted to transport problem, which is one of the main problem of any logging company activity. On fifth all the world?s volume of woods belongs to the Russian Federation. Due to the fact that cutting fund is distributed an unevenly and a part of it is in hard-to-rich places it is use is not effective enough. Approximately 40-70 cubic meter of potential raw material per hectare remains at cutting area. Cutting waste and felling residues great removal is considered to lead to transport costs in Russ...

Anthropogenic load is the main cause of forest fires near settlements and various objects of transport or industrial infrastructure. It is proposed to mark out a point source of anthropogenic load. Similarity in the processes of propagation of anthropogenic load and diffusion heat transfer was used for simulations. The quantitative characteristic of the anthropogenic load is the virtual (possible) number of forest fires in a controlled forest-covered area. A one-dimensional mathematical model for estimating the sp...

Understanding human impact on land-cover and capacity to monitor change is fundamental to sound research and informed decision-making to address Global Change and ensure sustainable development. While remote sensing technology is evolving rapidly, and multiple land-cover products have been developed, the lack of detailed information on land-cover remains a major problem. Analysis of vegetation in the study includes the assessment of different tree species and provides a broad-scale evaluation of available land-cov...

Out of allbroad-leavedspeciesthat are to be found in our woods, ash trees have a special importance throughboththe great value of the wood andthe cultural qualities.The imbalancesin forest ecosystems due to the influenceof some climatic and anthropic factors havematerialized in the occurrence of some gradations of defoliationinsects, among themStereonychus fraxiniDe Geer, 1775.In the last few years the ash tree stands were increasinglyaffected, which requiredeven more careful preoccupation withthe prevention and c...

Preservation of the environment becomes a vital issue in an era of intensive societal development. The long-term economic development of areas with low forest cover and poor composition of woody vegetation leads to a sharp decline in biodiversity and the deterioration of trophic connections. Forest ecosystems are those components that are capable of stabilizing the environmental situation and solving economic and social issues. Forest plantations play a special part in preserving and maintaining ecological balance...

According to State Forest service data in 2018 Norway spruce occupies 19% (0.533 milj. ha) from total forest area in Latvia. Disease and pest intense spread and damage in different forest ecosystems is result of climate change creating a risk to forest management. Spruce bus scale (Physokermes picea Shrnk.) in Baltics including in Latvia up to 2009 were detected only in parks growing trees but after 2009 also in different age P. abies stands especially on drained soils including Myrtillosa mel. Research aim is to ...

Hybrid larch is fast growing and more wind-resistant than Norway spruce; thus, it might be a suitable alternative to reduce (diversify) the forest management risks in context of climate changes. However, interest to use this species in forest regeneration, recently higher than before, is still limited. In part it is related to lack of experience and information on its growth. Therefore aim of our study was to characterize growth of Larix x eurolepis young stands in Latvia. Sample plots were placed in 7 stands of t...

Orchis galilaea is the only Lebanese orchid that is restricted geographically to Lebanon, Palestine and Jordan. It is a terrestrial orchid that attracts its pollinator by sexual deception while offering no reward. The full distribution of this orchid in Lebanon has not been determined. This study is part of ongoing research into the population dynamics of the orchid to form a management plan for its conservation. A Geographic Information System (GIS) was used to identify the habitat characteristics of O. galilaea ...

Forest is the main resource of Latvia. Forests occupy 52% of the total land area of Latvia. Since ancient times forest has provided humans with basic necessities, yet over the course of time the role of forest has changed. Nowadays lumber production plays the primary role, while gathering the other forest products represent forest sub-uses. The research aim is to analyse the production of non-wood forest products in Latvia from various perspectives. The research employed the following methods: monographic and grap...

The results of the studies have shown that the total C reserves of the dark coniferous forest phytomass of the southern taiga in the south-eastern part of the Western Siberia vary from 75.8 to 129.0 t/ha in secondary birch forest and from 48.9 to 110.5 t/ha in fir forests. The analysis of the production process in dark coniferous forests of the southern taiga done using such parameters as absolute value of the C biomass growth, specific annual production of wood and efficiency of assimilation apparatus work, has d...

Analysis of forestry fund and especially of the silvicultural fund represents more and more a multidisciplinary subject, interesting for the purely theoretical sciences and also for the sciences with wide practical application. One of the characteristics that generate interest is the spatial-temporal ?mobility? of forests, and also the possibility of satellite approach, by means and methods specific to remote sensing. The area of interest, a case study in this paperwork, is extended from the mountain region to the...

Timberline and treeline ecosystems are one of the most sensitive to climate warming. The sensitivity and response of treeline vegetation to environmental changes, especially to climate extremes, are increasingly discussed. Since treeline heterogeneity appears from regional to smaller scales the approach must be improved by including time scale from short to long-term. In treeline ecosystems the height growth of tree species in the first decades of life are good indicators of adaptability to climate changes. The he...

The sessile oak is the widest spread species of all autochthonous oaks species in Romania, forming a lower level of vegetation. The purpose of this study is to analyze the variability of leaf nutrients, as well as of soil nutrients, for two sessile oak stands situated under different forest site conditions. These two stands are located on the same type of soil: luvisol. As such, four soil profiles were realized for analyzing soil properties. Leaves samples were collected from twenty sessile oak trees, during three...

The research was carried out in the meadows ecosystems in the Bazo? forest park, located between Timis and Bega rivers and in the Cornetu forest, situated in the meadow of the Arges river. In each 1 ha survey area, information on the biometric features of component trees was collected and increment core samples were extracted. The purpose of the research was to know the structure and the functioning of the specified crop stands and the elaboration of the dendrochronological series for pedunculate oak and common as...

Created for the purpose of stabilizing the tailing dumps from Moldova Noua against wind erosion, the forest plantations successfully fulfill theirs eco protective role. The arrangement of plantations along the slope or plateau of tailing dumps are determining a different development in vertical and horizontal structure, depending on density, composition or site conditions. The structure study of the stands from tailing dumps was made by processing data obtained from sample surfaces located on the plateau or slope ...

Large reserves of forest resources (according to UN estimates, the area of forests in the Russian Federation, is 8.5 million km?) have provided a significant development of the forest industry. Together with large investments in the timber industry complex, it became possible to optimize the technological processes, machines and equipment of enterprises. At the same time, it is also necessary to solve the issues of the most rational forest management. Sustainable forest management assumes limiting of the volume of...

The paper presents observations of solution of the sustainable forestry problem in terms of the Arkhangelsk region. One of the sustainable forestry guidelines is appropriate restraining of the forest harvesting. The volumes of logging in the Arkhangelsk region constitute about half of the allowable wood removal. One of the reasons of the harvesting volumes insufficiency is low density of forest roads network, therefore the accessible areas alongside the existing roads are depleted. The forest roads network should ...

This work, which was conducted in the Chettaba forest, focuses on the sylvicultural treatment of Pines during its first natural regeneration. It will ultimately emphasize the importance of forestry sustainability. This sustainability consists of the rational management that should begin right after the exploitation as well as during all stages of growth. In fact, it appears that during the past couple of years, forestry exploitation seems to occur in destructive and illegal ways and that restoring processes are no...

The paper presents and analyses different solutions to determine the alignment to be taken into account in designing forestry roads in order to prevent and remove the effects of natural calamities. The proposed solutions take into account the area of the forestry roads in order to integrate them harmoniously in the region landscape. The paper also presents a case study concerning the solutions adopted to remove the effects caused by the natural calamities in the summer of 2016 on certain forestry roads in the Timi...

The aim of this study is to estimate the outcome of special cutting method developed for old pine stands in Riga?s forest park Mezaparks. Its topicality is defined by the increase in urban population, cities? areas, and green spaces there. The functions of cities? green areas are specific and it is very important to develop and evaluate special methods of forest management for urban forests. The research was carried out in the forest park Mezaparks, in a 183-year old Scots pine stand with an area of 4.32 ha, where...

The climatic changes effects manifested through extreme meteorological phenomena (wind, temperatures, precipitations) are highly affecting forest vegetation. A rare meteorological phenomenon (freezing rain), associated with an intense wind was encountered in 2015 towards the end of the vegetation season (October, while the leaves had not fallen yet). This phenomenon has caused important damages in the common beech stands located in Romania?s Sub Carpathians. The present paper presents the results of investigations...

References to theoretical research of aerostatic bearings and the method of their analysis for choosing options of aerostatic direction are provided. The calculation is done by means of a numerical method based on the field pressure approximation in a gap by means of differential algebraic equations, which takes into account two-dimensionality of the lubrication flow in bearings of various configuration and gives results close to actual ones. With the assumptions made in order to simplify calculations, flow line d...

The research analyses and evaluates changes of dendrometric indices of Scots pine (Pinus sylvestris L.) young growths over years, characterizes the impact of various factors on growth course. The investigation includes data of 84 sample plots arranged in western, central and eastern regions of Latvia. The established sample plots comprise forest compartments in Vacciniosa, Myrtillosa, Hylocomiosa, Vacciniosa mel. and Myrtillosa mel. site types. The data obtained in sample plots were collected in period between 201...

Romanian forest and vinicultural ecosystems were strongly affected by climatic changes, especially during the last two decades. The main changes manifested in the health state of these ecosystems were analysed based on data from national monitoring, forest management plans, as well as from national forest statistics (in the case of forests). Furthermore, harmful insects were inventoried and captured with adhesive yellow traps and analysed together with moths captured with traps containing Atrabot synthetical sexua...

Poland?s forest cover accounts for 28.8% and is lower than the average for Europe, which is 32%. The first programme to increase the afforestation rate in Poland was developed in the year 1993 and was titled "The National Programme of Increasing Forest Cover". The document was a strategic study intended for use as an instrument of forest policy in the field of shaping the environmental space of the country. It contains general guidelines for drawing up regional spatial development plans in the scope of increasing ...

The structure of the complex index of viability of CPE is proposed: the complex index of the viability of CPE is a vector whose components are partial indexes of CPE: the index of the condition of CPE; the index of structural varieties of CPE; the equivalent level of noise in CPE due to the movement of transport on the railway lines; concentration of metal salts in CPE; the level of radiation. It is proposed to investigate CPE with the help of a compartmental analysis, in this case, the degree of controllability a...

The purpose of the researches undertaken finds it origin in the scientific and practical concerns regarding the accumulation of knowledge with regards to the characteristics of the natural frame and of the social-economical particularities as elements which define the structural frame in the waste management and of the possible pressures upon the quality of the environment. The importance of the subject tapped derives from the fact that besides the food, clothing and wood necessities, the natural environment (soil...

The paper suggests a mathematical model, which is to evaluate interaction of a wheeled mover and forest soil. The model is composed by compiling results, which were obtained by independent researchers in the framework of vehicle locomotion theory under off-road conditions and authors` obtained dependencies. In particular, the model includes refined formula for calculating shape of contact area with the ground (formula allows to take into account the deformation modulus effect on contact area shape), for calculatin...

The paper presents a mathematical model designed to calculate the depth of the rut formed by a small-sized skidder on soft soils. The model bases on scientific research in the theory of off-the-road locomotion, completed with the authors? own theoretical developments. The model uses deformation modulus and bearing capacity as integral characteristics of strength and deformability of the soil. Moreover, because the deformation modulus of soft soils has a low value and is comparable to the normal stresses, the model...

The study of intra-annual dynamic of wood formation is one of the most progressive and fast-growing fields in plant sciences. The main anatomical characteristics of tree-ring structure, e.g. number of cells and radial cell size, are closely related to the kinetics of cell production. In this case, the timing of seasonal production is a fundamental aspect of plant development and functioning. To better assess the impact of specific climatic events to the timing and dynamic of growth, a process-based modeling can be...

Phenology is a study of timing of event taking place in nature. In a functional ecosystem phenological phases for mutually dependent are synchronized. In a rapidly changing climate there is a risk of decoupling, that is spring development of interdependent could species proceed at different peace. We are investigating the likely timing of spring phenological phases during the last and upcoming centuries for two tree species common in northern and central Europe: bird cherry (Prunus padus known also as Padus racemo...

The study of issues related to the cost of production of biofuel deals with most modern countries. The cost of fuel is one of the most important indicators in the production of various types of energy. The cost of production of biofuels from wood is affected by many factors. Constant components of the cost of production of fuel chips are the collection, removal and shredding and loading of wood chips into motor vehicles, which are 500 rubles/m3. Transporting and unloading chips in the consumer is a variable compon...