Highlights:
- Under the conditions of there being an identical load on the tyre of agricultural gantry system, the efficiency of its wheels increases with any increase in the tyre diameter and width.
- The choice of tyre size for agricultural gantry systems should first be based on its suitable width and then on its diameter – a parameter that determines load-bearing capacity.
- When optimising tire parameters of the agricultural gantry system, it was found that, under given conditions, an outer diameter of 1.245 m and a width of 0.250 m proved to be the most suitable.
- The proposed methods of choosing tyre types for pneumatic wheels makes it possible to determine the tyre parameters for all kinds of agricultural gantry systems for travelling on compacted soil in permanent artificial tracks.
Highlights:
- The rolling of the agricultural gantry system’s wheel on permanent artificial tracks is accompanied by a lower slippage value, resulting in a higher tractive force.
- The agricultural gantry system loses less of its intended movement speed and uses less energy to reach that speed.
- The agricultural gantry system moves on soil that has been prepared for the sowing of crop, the maximum tractive force is generated at the slip coefficient of between 0.22–0.24 and when moving on permanent artificial tracks, this value decreases to between 0.15–0.17.
- The the maximum tractive force being generated by the wheel of an agricultural gantry system is higher when that system is moving on permanent artificial tracks.
- When compared to moving on soil that has been prepared for the sowing of crop, this value is at least 30% higher.
Highlights:
- Seed germination reduction by the aqueous extracts of Melissa officinalis was up to 54% of the untreated seed lot for each weed species.
- Native plants compared with invasive (like Conyza albida and Physalis angulata) are affected more due to the absence of tolerance or resistance to the allelochemicals.
- In the case of 10% concentration, emergence was reduced by 58, 54, 48, 46 and 43% for X. strumarium, C. album, S. faberi, C. canadensis and C. bonariensis, respectively.
- The allelopathic activity of M. officinalis could be further exploited as a basis for natural herbicides.
Highlights:
- Well-structured crop rotations of arable crops can give the time and the flexibility to the growers to effectively control the important weeds.
- The potential effects of intercropping on weed control can vary according to the soil and climatic conditions and followed crop management practices.
- The efficacy of delayed sowing (false and stale seedbed etc) and increased crop density against weeds can be further improved.
- The frequent shift of strategy, the flexibility and the adaptation to the specific conditions of each farm and agroecosystem are crucial.
Highlights:
- The work is dedicated to the Estonian erosion-affected soils (EAS) from which the eroded soils are year 2020 soils of Estonia.
- In Estonian soil classification (ESC) 11 eroded and 3 deluvial soil species have been distinguished.
- The eroded soils in ESC are determinated by the intensity of erosion and calcareousness of soils, but the deluvial soils by their water regime and thickness of deluvial horizon.
- In historic overview about scientific researches upon EAS of Estonia the essential facts and engaged with this persons are presented.
Highlights:
- The use of various treatments for the differential application of nitrogen in the precision farming system.
- The test sites with predetermined doses of nitrogen fertilizers for decrypt the obtained images were used.
- The method of applying nitrogen fertilizing using the test standards sites was used.
- The different nitrogen fertilizers application concerning spring wheat crops during 3 years were compared.
- Concerning the differentiated application of nitrogen fertilizers, grain with protein content is higher than when using zonal technology.
Highlights:
- Simultaneous method for determination of fluoroquinolones, sulfonamides and tetracyclines in sewage sludge, compost and plants was developed in Estonia.
- The sewage sludge and compost from Estonian wastewater treatment plants contained fluoroquinolones in remarcable amounts, the concentration of sulfonamides was comparatively low and tetracyclines were not detected.
- The migration of fluoroquinolones and sulfonamides from soil to plants was obvious, and concentrations of sulfonamides in plants were generally higher.
- The degradation rate of pharmaceuticals depends on the compound and sludge treatment technology.
- Sawdust as a bulking agent speeded up the degradation of most pharmaceuticals in sewage sludge, but no decomposition of carbamazepine was observed in any of the compost mixtures.
Highlights:
- Assessment of soil compaction by mathematical model and corresponding computer simulation system.
- Multifunctional modelling systems (computer simulation and simulation by vegetation miniatures) were carried out.
- The different cultivation methods (tilled and no-tilled) during 3 years were compared.
- Results of simulation by vegetation miniatures (guttation method) could be used to determine the minimum, maximum, and limit levels of dry bulk density, and the limits of smallest field capacity (SFC).
- One of important index is an agroempirical bearing capability by which could be described the situation and level of coil compaction immediately after traffic.
Highlights:
- It is possible to compare the species composition of forests and old manor parks, but to do so it is necessary to transfer the data derived from manor park inventories to match that of the Estonian forest inventory.
- The results show that the species composition of old manor parks differs significantly from most Estonian forests with the majority of the trees in parks being broad-leaved.
- The proposed method is suitable for comparing forests and parks on a generalised level.
Highlight:
- Bokashi tea improves the growth of tomato transplants by increasing stem diameter and is allowing for plants to take up more nutrients.
Highlights:
- Weeds as the biggest agriculture problem and alteration of cropping pattern to improve weed control.
- Manipulation of sowing date as a measure for weed management.
- Managing weeds through alteration in population density, higher seeding rate and narrow planting pattern.
- Managing weeds through crop genotype choice.
- Importance of adequate fertilization to improve weed control.
Highlights:
- Higher colony forming unit (CFU) values were registered in the reed-bale buildings during the study. In the straw-bale buildings the same values were lower. There were seasonal differences in both cases. The study carried out revealed that the indoor air of the straw and reed-bale dwellings includes more colonies than the outside air. No mould growth was detected during the study.
- Comprehensive approach to the indoor climate of the straw and reed-bale buildings enabled to determine a problem in the construction of reed-bale buildings, which was probably caused by the inadequate density of reed bales. Further studies need to be carried out to validate the finding and a data logger needs to be installed near the ceiling (upper joint).
- The results of the research of the studied buildings' indoor climate show that a straw-bale or reed-bale house is suitable in Estonian climatic conditions and is a healthy and environmentally friendly dwelling when expert planning, suitable materials, and quality craftsmanship are used.
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Published 06-29-2020