Maintaining soil fertility is one of the main objectives of agricultural production. An important factor in soil fertility is its optimal structure. For the minimum cultivation of soil widely used equipped with spherical cut-off discs heavy harrows. The purpose of their use, along with others, in the cultivation of heavy soils, for example, chernozems, is the depression of soil boulders and, thus, the optimal structure. In the conditions of intensification of agricultural production under the influence of such soil-working tools in the cultivation of malocontuitive sod-podzolic soils and running gears of mobile equipment, the destruction of the soil structure, the reduction of the number of agronomically valuable water-supply units, and the spread of soil. Thus, for the cultivation of such soils, it is necessary to use discs of another profile, which would ensure the minimum destruction of agronomically valuable watertight aggregates. In order to create such a working body, the process of structuring the agronomically valuable water-conserving aggregates, factors influencing it and analyzing the energy criteria for the formation of a water-tight structure is considered. The features, which arise during mechanical cultivation of soil, influence of cultivation on its structure and features of the stress-strain state of soil are studied. A mathematical model is developed that allows calculating the stress state of the soil and designing the most rational form of disk working bodies. In the conducted studies, the influence of the depth of cultivation, the number of cutouts, the size of the cutout angle and the length of the chord of the projection were studied. On the basis of the developed mathematical model, a rational profile of the disk working organ for the cultivation of small-coupling sod-podzolic soils was obtained and its tests were performed, which showed a decrease of the erosion-dangerous particles of the soil by (<0,25 mm)  24%.

The aim of this study is to compare productivity and costs of medium-sized and small-sized harvesters in pre-commercial thinning. In this study the data on harvesting productivity were obtained in stands, where biofuel was prepared using two medium-sized and two small-sized harvesters equipped with different harvester heads. In total 677 m3 of wood was prepared with medium-sized harvester, but with small-sized harvesters 1 164 m3 of wood was prepared. Although the total annual costs of small-class harvesters are lower by 16 %, comparing with middle-class harvesters, the productivity rates shown by the middle-class harvester John Deere 1070 E (equipped with H 754 harvester head) are significantly higher and the average wood preparation costs are lower, comparing with the other harvesters employed.  

The main objective of the article is to present the level of education in some selected countries, and to explain how education determines a sustainable growth. Education is the main factor to achieve both economic and employment growth. At the same time, education plays an important role for a sustainable improvement of the standard of living in the world. Supporting education is also one of the aims of the 2030 Agenda for Sustainable Development (Goal 4), but education appears in a number of other SDG targets too. The countries that allocate the most capital for education are Norway, Denmark, Sweden, United Kingdom, Belgium, Finland (over 6.7% of GDP). The share of GDP allocated for education in Romania is only 2.7. This directly affects both the physical conditions for carrying out educational and research activities in school units and the qualitative level of the educational act. The Pearson correlation coefficient (r) between the real GDP/capita (VAR01) and share of GDP for education (VAR02) for our study is 0.694, which again underlines the close correlation between the allocation of funds for education and research and the level of development from a country. The Pearson correlation coefficient (r) between supporting education from GDP and top 100 universities is relatively low (r = 0.287), reflecting an insufficient correlation between the two variables. As a result, the education system in a country must be adjusted and supported both financially and through the adoption of viable policy decisions that will ensure increased performance in the educational system.

Aim of this study is to develop a method for automatic shallow drainage ditch generation to drain terrain depressions using four factor least cost surface which is obtained using LiDAR (light detection and ranging) data and Sentinel-2 multispectral satellite imagery. LiDAR data are used for depression mapping in DEM, flow accumulation and slope modelling as well as CHM (canopy height model) to obtain relative vegetation height. Sentinel-2 imagery was used for land cover type identification as well as separating coniferous and deciduous forest stands. Study area is located in western Latvia and is 25 km2 large. Least cost surface connects DEM depressions and already existing drainage ditches by best possible path for shallow ditch network digging. Different methods are applied to determine depressions which can be drained as well as changes of affected drained area and depression depth. This results in suitable areas where to create shallow ditches to improve water runoff. Results show that using this method average reduction of area of depressions is 79% and average length of shallow ditches on each drained depression hectare is 370 m.

Rumen is a complex ecosystem where feed consumed by animals is digested by the help of rumen protozoa. They plays an important role in contributing nutrients to the host animal. This study aimed to investigate the effects of dietary inclusion of unicellular microalgae Chlorella vulgaris spp. on total count and generic composition of protozoa in cows rumen. In this study, dietary treatments were tested during three 21-d experimental periods. Each of period content different amount of microalgae supplement. In the first experimental period in cows feed was added 30g (3,14g/kg of DM) of Chlorella, in second period-90g (9,6g/kg of DM) of Chlorella and in third period-170g (18,7 g/kg of DM). As a result of this study, ciliates of 10 genera were detected and identified. The number of this genera and total amount of ciliates were counted. The analysis of rumen protozoa population in tested cows shows visible effect of the presence of microalgae in cows dietary. In particular, the density of ciliates protozoa of the cows treated with 90 and 170 g of algal supplement was visibly higher compare to results from the control diet. Microalgae-based supplement diet had stimulative effect on ruminal protozoa population and caused increasing of many protozoa genera such as Isotricha, Dasytricha, Charonina, Buetschlia, Ostracodinium, Ophryoscolex.

The modern agricultural system is wasteful, with Europe generating some 700 million tonnes of agricultural and food waste each year. In the context of the agri-food chain, the ‘circular economy’ aims to reduce waste while also making best use of the ‘wastes’ produced by using economically viable processes and procedures to increase their value. In this paper we will try to frame the key issues associated with food waste into the emerging bioeconomy and circular-economic mode, suggesting that these three concepts are intertwined, and considering them unitarily might provide win-win solutions that minimize wastage, promote income growth and job creation, and prompt sustainable local development. In terms of performance and economic considerations, peat is in many ways an ideal constituent of soilless growing media. Peat has become the material of choice throughout plant production systems from propagation to saleable ‘finished plant’ material. However, the extraction of peat has well documented negative impacts on the environment; arguably the most important of these is the release of stable, sequestered carbon into the active carbon cycle, thereby exacerbating climate change. During the last 20 years, peat extraction has come under increasing scrutiny throughout Europe and particularly in the UK. This has generated an abundance of studies examining a diverse range of alternative materials (as compost, vermicompost, digestate, biochar). In the selection of new materials, environmental considerations have become as important as performance and economic cost. In this context there has been a justifiable emphasis on organic materials derived from agricultural, industrial and municipal waste streams. For future urban sustainability it is necessary to develop integrated processes, which can be part of a circular bio-economy. However the challenge still remains of simultaneously recycling the nutrients from the waste. The greenhouse horticulture applied to nutraceutical species is the ideal sector for improving the conversion rate of organic waste into food and health friendly products. On farm composting/vermicomposting/pyrolysis/anaerobic digestion and the use of the end-product to the partial substitution of peat in nursery activity allows reducing the environmental and economic costs in the production of potted plants.

In Latvia peat production is historically important economic sector, giving significant contribution to rural economic development and providing work places in rural areas, where other job opportunities are limited. Every peat extraction field has certain lifespan, based on economic, social or ecological assumptions. Every peat field could be extracted for set period of time, after which peat extraction is not feasible any more. Current legislation in Latvia requires re-cultivating of places, where mineral resources, including peat, were extracted. Aim of the study is to evaluate afforestation as one of the cut-away peatland re-cultivation possibility. Economic analysis were done for extracted peat field afforestation with birch, black alder, grey alder, pine, spruce, hybrid aspen, poplar and willow. The economic calculations were done comparing different timber products from plantations, different planting materials and plantation lifespans. Lowest investment costs for plantation establishment on cut-away peatlands are for pine and spruce plantations and highest for willow plantations. Highest revenues in plantations with 20 years rotation cycle are in poplar plantations with 0.2 m cuttings and lowest in grey alder plantations. In plantations with rotation cycle 40 years highest revenues are in hybrid aspen plantations and lowest in pine plantations. 

Individual municipal waste streams of Kaunas (Lithuania) in the period 2012-2015 period was found that mixed municipal waste collected in the city of Kaunas municipality, prefabricated containers, compared to the 2012 decreases. 2015. Collect points mixed municipal waste are reduced from 118,065.56 tons to 100,470.6 tons, accounting for 15%. Biodegradable (green waste) quantities of green waste collection a site does not increase compared in 2012 and 2015. (in 2014 these waste was not collected). The decrease may be affected by that green waste is used boiler house that green waste for energy recovery. The recyclable waste separate secondary maximum (4.5 times) Increased quantities of collected waste paper, plastic positive capture an increase of 1.5 times. Glass collection containers steadily decreasing (from 2.46 tons 2012 to 1094 tons 2015). The trend to rise only noticeable only after complementary systems and DGASA (deposit system). In particular increased textile waste collection (up to 10 times). Toxic waste collection Kaunas City Municipality is constantly increasing tire (up to 2 times); waste containing mercury and packages containing hazardous substances (up to 3 times.). Electrical and electronic waste collection throughout the 2012 -2015 year. Period effective complementary systems (collected 99 % of such waste), but the amounts vary from year to year, and substantial growth was observed. Population change shows that especially affect the population of secondary separate paper (r= 0.994, p = 0.04), plastic (r=0.923, p =0, 0.047), tires (r=0.960, p =0, 0.040), and toxic waste (lamps, and hazardous materials) collection. According to the results it can be said that some of the waste (green, glass, electrical equipment) gathers a group of people decided to lead.

The success of the forest regeneration with planting is determined by many factors and one of them is soil preparation. Chosen soil preparation method impacts different environmental aspects and one of them is soil temperature and that is one of main abiotic factors determining the growth of roots.   Development of the root system is a key prerequisite for growth of newly planted trees. The aim of this research was to assess the impact of the soil preparation method on the surface (5 and 20 cm) temperature of the soil. The study was done in 8 young stand sites with different soil preparation methods, soil preparation design (orientation relative to cardinal points) and different forest types in central and north-western part of Latvia. Soil temperature measurements were taken at 5 cm and 20 cm depths in both sides of furrows and in spot mounds at every study site with hand held thermometer, in few young stands unprepared soil temperature was also measured. Mean values and standard error were calculated and the statistical significance was determined by:  the Shapiro-Wilk normality test, the Kruskal-Wallis Test and pairwise Wilcoxon test with a 95% confidence level. Our results show that soil preparation positively impact soil temperature compared to unprepared soil and soil temperature in spot mounds was significantly higher than in furrows during clear and hot (27-32°C) day at both depth and in overcast weather with moderate air temperature (20-23°C) in depth of 20 cm.

Nowadays it is paramount to promote bioenergy for climate protection, energy security and creation of income/jobs. In this perspective, Anaerobic Digestion (AD) for biogas and digestate production seems to be a viable way to simultaneously improve waste management while producing Renewable Energy Sources (RES). The main objective of this work is to assess the environmental impact associated with biomethane and digestate production from an AD plant as Global Warming Potential, expressed in CO2 equivalents. Therefore, a LCA was carried out for the production of biomethane ready for the injection into the Italian distribution natural gas grid. A mix from different waste sources (cattle manure and slurry, pig slurry, Citrus industry by-product, chicken manure, manure from broilers, triticale silage and waste from vegetable cleaning) is considered for biogas and digestate production. Besides biomethane this plant will produce digestate, that is a biological and nutrient-rich fertiliser. Thus, the cycle of circular economy is closed, as the recovery of matter and energy is carried out from waste. The results clearly indicate the importance of the process steps transport of biomass to AD plant and, above all, methane upgrading (separation by membrane). Depending on the high amount of the substrate and long distance travelled, Citrus waste substrate transport accounts for the largest share in GHG emissions with 0.229 kg CO2-eq/Nm3 or 70.5 % of total transportation emission. Greenhouse gas emissions estimated for the various process stages for the Sclafani Bagni plant showed, that methane upgrading emits 1.95 kg CO2-eq/Nm3, while other processes totally emits 0.525 kg CO2-eq/Nm3. The LCIA results confirmed the negative total impact of the process with grid injection, in terms of kg of CO2 eq.: the LCA verified the carbon-negative-bio-energy concept of the project. Therefore, biomethane derived from biogas is an entirely renewable and readily available low carbon alternative fuel, that can be locally produced from organic waste and capable to replace the fossil natural gas in the near future.