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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....

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 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...