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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 ...

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 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 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...

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...

This study is aimed at evaluation of organic carbon dynamic after compost application. Object of study was heavily degraded Calcaric Chernozem (Vele?ovice) localized in the south region of Moravia in the Czech Republic, during the field experiment 2012?2016. The experiment was established in a sugar-beet growing region, the altitude of this locality was 298 m a.s.l. and the local climate was classified as warm and slightly arid. Values of long-term average annual precipitations and annual temperatures were 490 mm ...

Our investigation has been focused on establishing the slowing down plant growth at the border of polytunnels. In order to determine the limiting factors of plant growth, we have conducted studies on soil properties, entomofauna and soil mesofauna. The research has been carried out in several polytunnels located in North Eastern Romania (Bac?u, Ia?i, B?rlad, F?lticeni, H?rl?u, T?rgu Frumos, Matca-Tecuci) In the field were developed and characterized soil profiles and samples were taken to determine the states of c...

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...

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 value of wood is only, if it has good appearance as well as mechanical and physical properties. During tree's life, it is influenced by various factors, the effects of which changes wood properties causing different damage to tree stem. Wood defects are caused by biotic, abiotic and anthropogenic factors. Defects of tree stem arising from non-parasitic origin occur on the stems, branches and roots. In total, 86 pure and mixed stands of Norway spruce were surveyed, but this study includes only 11 young forest s...

A retrospective monitoring of the land use change in the bottoms of mesodepressions in the Azov District of the Rostov Region in the period from 2014 to 1968 was performed. A cartographic analysis of the changes in soil overmoistening in closed mesodepressions by its indication based on changes in the land use reflected on remote sensing materials was made. The research was carried out within the framework of the problem-oriented system of retrospective soil and land cover monitoring. They revealed that the curren...

The properties of buried soils reflect the paleoclimatic and ecological conditions of past eras. The study of these properties in pedo-chrono-sequences, the duration of functioning of which does not exceed several hundred years, allows reconstructing climate changes with the greatest possible accuracy for the studied period. The paleosols buried under burial mounds (kurgans) and surface soils were studied on the territory of the southeastern margin of the Russian Plain, in the Southern Cis-Urals (Orenburg region)....

The present paper demonstrates capabilities of flicker-noise spectroscopy (FNS) as a phenomenological approach to the analysis of astrophysical objects? time signals using an example of the study of quasars radio-wave radiation dynamics in various frequency ranges (S band (2 GHz) and X band (8 GHz)). The promise of FNS application to the study of signals generated by accreting astrophysical objects is caused by inclusion of informational parameters characterizing the components of time sequences in various frequen...