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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...

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...

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...

In the years 2011-2016 the effect of different agronomy practices on changes in topsoil qualities of Chernozem was studied. Soil quality refers to the ability of soil aggregates to resist dispersion. Two soil tillage treatments were established ? disc tillage and fallow. The locality is situated in the Mikulov district in a maize-growing region at an altitude of 350 m. The average annual temperature and precipitation was 9.6 °C and 524 mm, respectively. Local soils were characterized as medium-heavy Chernozem on l...

Arid ecosystems occupy large areas in the world and perform important ecological functions to maintain the biodiversity and stability of natural ecosystems. In this article, we present the results of the research on the change in the activity of catalase and dehydrogenases when the soils of the arid ecosystems of the Southern Russia are polluted by zinc: dark chestnut, chestnut, light chestnut, brown semidesert and sandy soil. Zinc was added to the soil in the amount of 300, 3,000 and 30,000 mg/kg (1, 10 and 100 m...

The industrial activity of the last century has led to the severe environment pollution, especially in the areas where mining and smelting processes were involved. The impact of atmospheric emissions from the metallurgical plants was detected at great distances from the emission source. The main units for the processing of non-ferrous ores (in Romania) were located in Baia Mare (Maramures county ? MM), Copsa Mica (Sibiu county ? SB) and Zlatna (Alba county ? AB). In the Alba and Maramures counties there was and st...

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...

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 ...

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 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...

Maize is a major energy crop for the production of silage, processing in a biogas plant, or livestock feed. However, its cultivation is associated with the possibility of soil erosion and other soil degradation processes. This paper deals with the comparison of the development of the root system of maize and selected leguminoses ? Broad bean (Vicia faba L.), Common vetch (Vicia sativa L.), White lupin (Lupinus albus) which can be grown in mixed culture system (MC). Four variants of the experiment were prepared in ...

The objective of the paper is to emphasize the influence of the reclamation works of sloping land with medium-gradient hills on the field capacity and water distribution on the soil profiles located on the upper, medium and bottom ameliorated slope. The study of retaining water capacity of soils was carried out on a slope with eastern north-eastern exposure of the Ezareni farm. Soil samples were taken in spring of 2017 and 2018, immediately after the snow was melted, from 10 to 10 cm on 100 cm depth. Soil samples ...

Use of fertilizers and plant protection products for yield increases led to environment pollution. There is intense concern for new materials development with controlled immobilization/ holdup/release role of compounds that get involved in plant nutrition and protection. Multiple beneficial effects of humic substances upon soil ecosystem is the reason that their control and conservation take priority. Part of the research results carried out regarding humic substances (HS) holdup on biodegradable, bio polymeric st...

Recently the ecosystem services (services) have been increasingly considered in ecology and soil along with ecological (biogeocenotic) soil functions. This approach is justified by the need for a comprehensive assessment of soils, including the economic one. In laboratory and field experiments, the pollution of ordinary chernozems with heavy metals and oil has resulted in oppression of biological properties of soil: activity of catalase and dehydrogenase, abundance of the Azotobacter bacteria, the germination and ...