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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...

In Latvia, according to Central Statistical Bureau data (2018), the agricultural industry employed 76.4 thou. employees in the main job as well as 49.4 thou. seasonal workers. For this reason, this industry plays an essential role in the national economy, and with the industry developing, labour-saving technologies are increasingly introduced to reduce manual work in agriculture. Besides, mineral fertilisers and plant protection products are intensively applied (organic farms are an exception) in order to increase...

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...

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 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....

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...

The use of bioenergy is gradually increasing, so are the number of different technologies to produce it. Particularly during the last years, new biogas plants had been built across Latvia to ensure more efficient use of farming and other agronomic waste or by-products. The aim of the research is to determine occupational risk factors at biogas plants in Latvia. The research summarises the risk factors of the biogas plant environment, compares the results of observations of biogas plants, performs a survey and an a...

The aim of the present paper is to give a brief review of results of computer simulating observations of the lunar rotation from the lunar surface. The simulation of physical libration of the Moon using the lunar telescope was performed on the basis of multiparametric analysis. High expectations in terms of obtaining accurate data on physical libration of the Moon are linked with SELENE Japanese project. The project implies an installation of the optical telescope at one of the Poles of the Moon. The observation o...

In this paper a theoretical and experimental study is performed, regarding the optimal seeds separation solution, by size and shape, in the air stream, given by a centrifugal fan, on the sieves of an experimental stand. The stand is also equipped with two blocks, each with two sieves whose slopes have been adjusted to four values. The determinations were made on winter wheat (Triticum Vulgare), winter barley (Hordeum Vulgare) and millet (Panicum Miliaceum), for several values of the inlet flow. Experiments were ma...

The development of the agricultural industry and increasing demands for bio-based products adds pressure on natural resources, such as water and soil. Soil is non-renewable resource and provides many ecosystem services, namely food and biomass production, water purification, nutrient cycling, carbon sequestration and habitats for biodiversity. The simultaneous achievement of socio-economic and climate policy objectives is challenging and requires careful management of soils as a pivotal resource. In Latvia, the ke...

Aerospace engineering is the engineering field concerned with aircraft and spacecraft development and operating. Thus it correspondingly has two major and actually overlapping sectors, as aeronautical and astronautic engineering. Aeronautical engineering was the original term for the field, but as flight technology advanced to include craft operating in outer space as well, this means the field of astronautics, the broader term of aerospace engineering has come since a while into common use. Aerospace engineering,...