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According to national forest statistics data of 2018, Picea abies occupies 18% of the forest area of Latvia. As a result of intensive forestry management a forest productivity and the diverse anthropogenic influences on forest ecosystems are significantly increased. During the life a growth of spruce young stands can be influenced not only by abiotic but also by various biotic and anthropogenic factors. An aim of the research was to analyze sanitary condition of the artificially regenerated young forest stands of ...

Windstorms are one of the main factors causing damages in forest in Northern Europe. The damages are especially severe, if the ground during the storm is not frozen and is wet, therefore the trees are less stable. Cyclonic windstorms primarily happens during the winter, and there is a prediction of notable rise of temperature in this period of the year ? thus we can expect more storm damages. It is known, that inside the forest stands specific microclimate exists, affecting also the soil temperature. However, ther...

The research was carried out in the ecosystems of sessile oak and beech within Vizantea forests of Experimental Forestry Base Vidra. There were located three plots of 1 ha each, where information on the biometric features of component trees was collected. The purpose of the research was to know the structure and functioning of the sessile oak and beech crops stands in the Curvature Carpathians, as a result of their current status, in the context of sustainable forest management and climate change over the last dec...

Stand structural diversity, defined as the diversity of trees in stands, can be indicative of overall biodiversity and habitat suitability, useful in forecasting stand growth, and provide within stand detail for forest inventories. The diversity analysis provides more detail to the traditional stand structure descriptions and enables the approach to stand management more consistent not only with the timber production, but also with other productions and values of the multi-benefit forest stands, and/or transformat...

Urban forests play an important role in ecology of human habitats and provide various eco-services. Urban forests improve and maintain air and water quality, act as local refugia for plant and animal communities, hold populations of economically important species (such as pollinators), and act as recreational areas for people and pets. All urban forest organisms are directly or indirectly affected by human activities often leading to changes in biodiversity. The aim of our study was to determine soil microbial bio...

The article devotes to experimental study of briquetting of woodworking waste, such as sawdust and shredded bark. The aim of the work is to obtain regression dependencies linking characteristics of briquetted raw materials and parameters of moulding process with properties of produced fuel briquettes. Controlled factors of the experiment include moisture content of the raw material; average particle size of the material; percentage of sawdust and bark in the material; moulding pressure; moulding speed. The target ...

The forest industry in the Russian Federation is actively developing. A large amount of material resources are invested in this industry. At the same time, technological and production equipment is being modernized, and the supply chains of forest products are optimized [1]. In the North-West Federal District of the Russian Federation in recent years, a large number of enterprises of the timber industry complex increase the volume of roundwood transportation by water transport, particularly in rafts [1,2]. To rece...

The article is devoted to the development of software tools to support elimination of wildfires in small regions lacking governmental financial resources and using volunteer help for in situ and remote activities. The latter activities include not only training but also monitoring and even creation of scripts, databases, web applications to simplify governmental firefighting service work and make some of their professional cases public. Murmansk regional forest firefighting service (located in northern Russia) giv...

The forests represent an important ecostabilizing factor in the country and soil is a component of the environment conditional on biodiversity, nutrition and the existence of life. Currently, there is shifting the focus from the protection of the soil fund area to the protection of soil and forest quality, while understanding the production function of soil and forest as part of their environmental function. The paper?s aim is to describe the chemical and physical characteristics of soils of the mixed forests. The...

Forest resources are the most significant natural wealth of the state of Latvia. According to the data of the 2nd stage of the forest resource monitoring for 2014, Latvia has 3575 thousand hectares of forest land comprising 55.3 percent of the total territory of Latvia, while the total timber stock estimated at 668 million cubic meters. Each forest stand has a certain amount of undergrowth and understorey ? small dimensions woody plants (shrubs) which is few researched until now. The most precise determination of ...

Local or regional forest loss may be considered a forest management problem that mainly affects countries that lack proper forest monitoring and law enforcement procedures. Romania is an appropriate example regarding this matter, the main issue being the massive illegal cuts that are difficult to monitor, record and sanction. Therefore, the desiderata of precluding this outlawed practice and of preserving the forest cover ? which accounts for almost 29% of Romania?s territory (2015), are not attainable without rev...

The forest road network administered by the National Forest Administration - Romsilva, with a total length of 26,500 km, was built, in the most part, between 1965-1990, when the forest railways were transformed in forest roads. Simultaneously with the extension of the forest roads network, the car transport there was imposed in the forestry sector, having both technical and economic advantages. Due to the special technical development, the transport vehicles have undergone a rapid modernization, which has led to t...

The paper objective was to emphasize the quality of the biodiversity life in an anthropic polluted soil and to underline the influence of the biological activity on the evolution and self-remediation of this soil. The studied site is located in the Apuseni Mountains, in the Ampoi Valley, on a slope ? 25%, facing north, under pine plantation. In the area, the prevailing soils are Cambisols and Luvisols formed into the coarse slope deposits dominated by sandstones. The site pollution was due to the atmospheric emiss...

Monumental trees are very important for biodiversity, the integrity of ecosystems worldwide and in many ways for people, because they are essential components of human cultural heritage and identity. Researchers have long claimed the bio-ecological importance of ancient trees and of those with great diameters and heights together with the necessity of preserving them for scientific purposes. In order for a tree to be selected as monument, it must have historical, folkloric or mystical characteristics. Moreover, a ...

The research is carried out to obtain the connection between the Earth magnetic field data and forest stand indices in Latvian forests. The hypothesis has been examined that magnetic field influences the growth of trees. The research object ? Ogre Region was selected according to the magnetic field deviation's map of Latvia. The data of Earth magnetic field measurements via satellite and the forest taxation indices were used ? there was designed the distribution of forest subquarters in belts of magnetic field rad...

The main goal of young forest tending is to create suitable forest stands with desired structure of tree species and certain number of trees for ensuring of sufficient growth space. Tending needs to be done both in naturally and artificially regenerated young forest stands by creating composition of forest stand and releasing space for growth of most perspective trees, which is done by removing trees of poor quality and one lagged behind in growth. Thus tending has a great impact on creating productive forest of h...

The article devotes to development of mathematical model of sawdust briquetting process, establishing relationship between the briquettes density, the moulding speed and pressing effort. The study uses elastic-viscous-plastic Bingham body stress-strain equation as a rheological model of the sawdust being briquetted, the model parameters are non-linear functions of the sawdust density; classical Runge-Kutta method was used for solving the nonlinear differential stress-strain equation. The calculations results show ...

Forests and the land where the forests grow are some of the key natural resources in Latvia. Forests occupy half of the total area of Latvia. Unlike other countries where deforestation is a problem, the forest area increases in Latvia owing to natural and artificial afforestation activities. The paper analysed changes in the reforested and afforested areas in Latvia in the period 2007-2017 and found that the most essential factors contributing to the reforestation and afforestation were national and European Union...

Forest tree species monitoring is important for forest management, habitat and biodiversity assessment, as well as carbon cycle estimation. Forest ecosystems provide important services to society, and sustainable management and adapted policies are essential to maintain their ecological and socio-economic functions. For implementing a good sustainable forest management it?s important to know about tree species distribution. To characterize forest was used during the time, field inventories who can provide timely a...

Global deterioration of surface water quality was attributed to a pair of factors: human activities and natural processes, including hydrological variability, climate change, weather characteristics, and adjacent land use. The study of water quality in the contemporary era is a current issue. This paper presents an analysis of the variability of water quality parameters in a study developed on 4 years. In a number of 5 monitoring points, 18 water status parameters were monitored. Primary statistic methods were use...

This work focuses on the extraction, the physic-chemical characterization, chromatographic analysis and the study of biological activities antimicrobial and anti-inflammatory pumpkin seeds Cucurbita moschata family Cucurbitaceae. Harvested area Lakhdaria in Bouira. The extraction of fatty substance by two methods with cold maceration and Soxhlet, it gives the best yield (41.61 %), the study of physic-chemical parameters has a refractive index (1.48), acid value (0.56 %) and iodine (180.6 g\100 g). And chromatograp...

The paper deals with the application of the pulse tomography Arbotom as a support decision tool for management of hardwood floodplain forest in the Czech Republic. The method of acoustic wood tomography is based on the finding that intact wood conducts sound faster than damaged wood with defects. Tomograph measures the time which takes a mechanical pulse (an acoustic wave) to pass the distance between sensors placed on the tree trunk. The evaluation of the trunk measurements in two-dimensional tomograms then shows...

The research aim is to identify the growth pace, productivity and quality of Scots pine in age classes I-IX in the forest type Callunoso-sphagnosa. Scots pine (Pinus sylvestris L.), which occupies 35% of the total forest area, is the most significant tree species in Latvia from the forestry perspective, yet the growth pace, productivity and quality of the species in the forest type Callunoso-sphagnosa have been little researched. The forest type Callunoso-sphagnosa is rarely found in Latvia; it is poor in nutrient...

The research aim is to identify the effect of a surface forest fire on the productivity and viability of Scots pine (Pinus sylvestris L.) in a 23-year-old stand. The research was done two years after a surface fire that occurred in 2015 in a 20-year-old stand, establishing sample plots both in the area subject to the fire and the fire-undamaged area as well as in a pine stand of identical age that had not suffered from a forest fire. The research measured the dendrometric characteristics of trees (height, diameter...

Dendroclimatic studies based on the use of various indicators of annual tree-ring structure (width, maximum density, cell wall thickness, lumen size etc.) have become widespread over the past decade. However, reconstructions of climatic characteristics revealed limitations associated with the use of both the width and density of annual rings. In particular, annual ring width, in the high latitudes of the Northern Hemisphere and in mountain regions, is usually closely related either with June, or June and July air ...

Natural disturbance regimes play key roles in shaping forest structure and development at stand and landscape levels. Disturbances are complex and variable, such that classical dichotomous characterization of disturbance regimes as following large infrequent disturbances or patch dynamics is too simplistic, especially when the resulting damage is more severe than the baseline of a single tree patch dynamic, but not severe enough to represent large infrequent disturbance. Ongoing climate change affects mountain Pic...

Forests are the national wealth of Latvia that is to be preserved and multiplied to meet the ecological, economic and social needs of society. Latvian residents with the forest has always linked the economic, cultural and emotional bonds that have developed over centuries. Forest performs essential ecological and social functions at both national and international level, and providing adequate growing and cutting stock measurements, we can estimate different growth factor influence. Historically this data delivere...

Climate change is reflected in the horizontal and vertical structure of vegetation cover, species composition, and bio-productivity changes as well as on the changes of carbon cycles. Landscape studies and revealing of climate changes in different landscapes are especially relevant for the countries/regions that on the one hand stand forward with high natural potential, on the other hand keen ecological problems distinguishes them. Among them is Samtkhe-Javakheti ? one of the region of Georgia. The research is bas...

At present, the monitoring of forest areas is a national requirement. The importance of protecting forests in mitigating climate change is well known. On the other hand, the economic aspects involving the efficiency of forest management imply correlation with the growing demand for wood on the market. From this point of view, the inventory and the evaluation of the rate of growth and yield of forest areas is extremely important. Estimating the growth rate per unit of hectare and the level of production of wooded a...

Climate change is affecting forests both directly ? via increased frequency and/or severity of meteorological conditions, impacting tree growth and/or survival (e.g. wind storms, drought spells etc.) ? and indirectly ? via improved conditions for diseases and pests. Also interaction between the biotic and abiotic factors plays an important role. It is important to consider these circumstances in forest management policies to ensure that forest owners remain interested (financially motivated) in forest management. ...

The work analyses an impact of a drainage system, established in 1939 on overgrown pine tree stand in longer period of time. For the purposes of study 14 sample plots, established by scientists K. Buss and P. Zalitis during the 50's and the beginning of 60's, were remeasured. Sample plots were organized in the Myrtillosa turf. mel., Vacciniosa turf. mel., and Callunosa turf. mel. forest site types. Stands basal area increased in all compared forest site types, maximal being 41.7 m2 ha-1 in Myrtillosa turf. mel. fo...

Climate change is expected to improve the increment of trees in Northern Europe, as suggested by results of numerous models. Recent analysis of empirical data from Central Europe have demonstrated an improved growth of Norway spruce over the last century due to several factors, including climate change. Aim of our study was to assess the changes of increment of young Pice abies on wet and drained mineral soils over a rotation period (80 years) in Latvia. Increment cores at breast height were taken from 119 trees a...

A major factor which affects the structure, function, and dynamics of forest ecosystems can be beyond climate, the use of the land, respectively land-cover change and pollution loading. The forest ecosystems can be affected by pollution, by alteration of biotic and abiotic properties even if they are at a great distance from the urban area. Human socio-demographic changes are the primary drivers of urbanization, and pollution and in turn, these patterns are influenced by the climate change and geography. Also, hum...

The paper presents a comparative analysis of the output of essential components from the Chaga fungus, depending on the growth conditions. The study compares the samples of Chaga mushroom grown in two different regions of Eurasia - Eastern Siberia and Western Belorussia. Classical method of extracting was used to get water extraction of Chaga; the method suggests that distilled water is poured into a flask with grind Chaga in a ratio of 1:6 and further put in a chamber for 5 hours at a constant temperature of 70В°...

The polluting substances are of industrial or agricultural origin, at the level of the different ecosystems. These are the effects of synthetic products on the fauna and flora we are interested in. So our use of biopesticides based on plant extracts, namely essential oils as a natural insecticide is our concern. These bioactive substances or molecules are of great ecological interest because they are very harmful to the ecosystem. The objective of this study is the use of the essential oil of Mentha peperita harve...

Considerable efforts have been devoted to the exploration of Latvian forest resources as the most significant national natural wealth. The State Forestry Research Institute is conducting the statistical forest inventory, is fixing the data of felling and recovery of forest stands. Detailed statistical information for the assessment of different aspects is available. In recent years, the consumption of certain woody biomass products, such as chips and pellets, has a tendency to grow, due to a number of factors: the...

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...

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...

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...

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....