Formation of yield in crop cultivation is affected by influence of many factors. Simple summation of individual factors is quite rare occasion. Interaction among factors is a dynamic value. The effect of interactions varies depending on the crop development stages as well as by graduation of factors. The study aimed to evaluate the soil penetration resistance effect on winter wheat grain yield and development. It allows specifying recommendations for soil treatment difference criteria for use in site-specific soil tillage. Field trials were carried out at the Research and Study farm Vecauce of Latvia University of Agriculture during the years 2005-2007 to investigate factors influencing formation of winter wheat grain yield. Forty seven points (distributed as grid 50x50 m) were selected in the winter wheat Triticum aestivum L. field. All points were attached to their geographic coordinates. Data shows significant effect of soil resistance to grain yield - increase of soil penetration resistance by 100 kPa cmE-2 reduced yield of winter wheat by 0.37 to 0.48 t haE-1. By contrast in 2007 a significant linear regression relationship between soil penetration resistance and the yield was not detected. Differences of fresh weight of winter wheat plants in tillering stage and the beginning of stem elongation were insignificant compared to different groups of soil penetration resistance at soil layers 0.10-0.30 m in both experimental years. Higher impact of soil penetration resistance on flag leaf area difference had soil resistance at the layer of 0.20 - 0.30 m and differences were significant in both trial years.

Deformations occurred in natural and regulated stream change beds lateral and longitudinal profiles. This is particularly evident in regulation furrows, where their initial state is known. Research showed that landslips of the upper slopes in regulated watercourses is the most common deformation (72.8% of studied cases), and the largest deformation occurs in the lower part of the slope (63.4%), where the accumulation of the moved silt and soil is. It was found that the deformation changes the bed plan as well. 59.1% of regulated streams distort furrows and make meanders due to deformation effects. The analysis of river beds widths and depths ratio relationship with discharge of channel running flow observed that ratio B/H increases with increasing flow evenly in regulated beds, while the above-mentioned ratio varies unevenly in the natural watercourse. Cross-sectional shape also varies in regulated and natural beds: heterogeneous form beds dominated in natural beds, while parabolic cross section shape is approaching during the deformation in regulated beds, what is more favourable for the living environment.

The article presents the comparative, descriptive statistics analysis of the changes of the Baltic Sea coast in the territory of the Republic of Lithuania. This paper analyzes the Baltic Sea coast measurements taken during the period between 2008 and 2015. The formation of the strip of the Northern breakwater - Giruliai during this period was influenced by the Hurricane Felix on January 10 of 2015. Describing the Baltic Sea coast strip dynamics trends, the Baltic Sea coastline change during the period between 2008 and 2015 was selected and calculated on the basis of the measurements results. Analysis of the erosive and accumulation processes of the 4 km long strip from the Northern breakwater to Giruliai strip was provided. The carried out data of the Baltic Sea coast changes analysis show that seacoast limits are constantly changing. The replenishment of the Baltic seacoast spatial data set during the period between 2008 and 2013 with the revised spatial data of the period between 2014 and 2015 showed that during the months of January during the period between 2008 and 2015 the 4 km long strip of the Baltic Sea coast decreased by 3.7075 ha, in the 1st Melnrage area, the 0.7 km long strip of coastline has moved more than 30 m inland. It was found that in the southern half of the researched section erosion processes prevailed, while in the northern part – both erosion and accumulative ones.