The investigation was carried out from 2006 to 2008 with the aim of observing the stability of morphological traits in Latgale's melon (Cucumis melo L.) lines in the Tukums region of Latvia. Four lines of Latgale's melons ('8', '14', '5(2)', and '4(3)') were grown in high plastic tunnels: five plants from each line. The following parameters were measured to determine stability of morphological traits in melons: fruit petiole and flower scar diameters (cm), length and wide of melon fruit (cm), and thickness of flesh (cm). Results showed that there was a significant difference in fruit petiole scar diameter between the years 2006 and 2007 for all lines. The melon line '14' was stable in all parameters from 2006 till 2008 except fruit flower scar diameter. The melon line '4(3)' was less stable in all parameters between all melon lines in all years of investigation.

The article discusses the results of comprehensive studies histomorphological signs of skin and hair of sheep (Degeress) of various stripes, especially the thickness of the skin and its layers that are commonly identified indicators. Studies allow to bring the scientific basis for the proper development of activities aimed at increasing production of wool, quantity and quality of which skin microstructure largely depends on. Sheep of different colors have a specific feature on the histological structure of the skin, which is essential for the development of effective methods of selection that enhance productivity of sheep wool. The researches have established that brown suit sheep has thickened skin as compared to red and gray color (p is less than 0.01). In turn, pilar layer of the skin is also much thicker at brown coloration sheep (2029.7 ×10E-6 m) than in sheep red (1850.6×10E-6 m) and sulfur (1773.7×10E-6 m) suits, the difference is statistically highly significant (p is less than 0.001). The thickness of the pilar layer is up to 70% of the dermis, which varies depending on sheep lear ranging from 1773.7×10E-6 m to 2029.7×10E-6 m. Reticular layer thickness varies depending on sheep lear ranging from 743.5×10E-6 m to 826.4×10E-6 m.

Hydro-physical properties of heavy or presses soil as well as water regime may be improved by various ways, taking into account the texture of soil and climatic conditions. Drainage is the tool for productive farming and economic benefit generation. Hydrological activity of drainage typically depends on project installation quality, anthropogenic and climatic factors. It is important to assess drainage activity under different meteorological conditions. One of methods to improve drainage performance is its installation with thickened humus layer. Lithuanian soil humus layer is close to arable layer and is equal to approximately 20–25 cm. The impact of humus on heavy-textured soil is multiple, since not only moisture regimes, biological activity, sorption capacity, chemical and biological characteristics, stability of plant nutrition are related with its quantity. The dynamics of drainage activity in soil with thickened (up to 40–50 cm) humus layer and with humus layer of natural thickness (20–30 cm) during various seasons of period of 1989–2009 is reviewed. Especially important indicator of drainage functioning – water runoff dynamics. The present article analyses the variation of climatic conditions and drainage runoff in the object. It is determined that the lowest quantity of precipitation in the researched territory during the research period is in spring and winter but the highest – in summer and autumn. During the research period the highest drainage runoff in the field I was during winter season (46.3%), in the field II – in winter and spring almost the same (32–33%).

Birch plywood has proved itself to be one of the most rational ways of wood processing. Growing demand of high performance birch plywood products requires a complex numerical analysis based on Finite Element Method (FEM), instead of using simple analytical assumptions, which prevent optimization of plywood construction (lay-up). In the research samples of birch plywood of several thicknesses, both sanded and non-sanded, with fibre direction of external veneer both in the longitudinal and transverse directions were tested. An extensometer and optical strain gauge were used for strain measurement. The FEM analysis, using commercial software SolidWorks Simulation Premium (SW), versus experimental bending and tension testing according to LVS EN 789 was carried out in this paper. The analysis of results indicates that there is a high correlation between the results of the experiments and the FEM. Particularly for in tension loaded specimens one can be tested up to the maximum ply strength (100 MPa); meanwhile, in bending up to 71MPa – the average stress in load bearing ply at the proportionality limit. Due to software restrictions, shear stresses cannot be evaluated. Future studies are considered to investigate terms for designing plywood with dynamic properties of strength and stiffness to be taken into account.