Table of Contents


    • Investigation of the power interaction of the ploughshare digger working body with the soil and sugar beet root for the conditions of its vibratory digging

      pg(s) 154-156

      the basic principles of the theory of interaction of the vibrating digging working body with the body of the root crop fixed in the soil at vibrating digging of sugar beets are developed. The force interaction of ploughshare diggers with the soil is considered in the work. The values of normal soil reactions acting on the ploughshare of the excavating working body are determined, which, when vibrating in the longitudinal-vertical plane, can dig out the bodies of sugar beet roots from the soil. Based on the obtained equations describing this process, the prerequisites for finding the kinematic and structural parameters of the excavating working body are developed.

    • Theoretical and methodological features of soil water regime optimization in pedagogical technologies of agroengineers training for innovative project activity

      pg(s) 157-162

      Innovative scientific-technical and pedagogical bases of studying in higher education institutions by future specialists in agroengineering of the theory and calculation fundamental questions of sprinkler nozzles and devices of machines for irrigation of agricultural crops are presented. Some constructive schemes of nozzles, namely, deflector, crack, etc. are analyzed. Graphs for determining the range of the jet and determining the rational shape of the nozzle are given. It is proved that all this can be effectively applied both in the educational process during the study of agricultural machinery and equipment by students and in research and production practice. Depending on the purpose, tasks, methods of technological processes of irrigation disintegration of a water jet on drops is analyzed. An algorithm for calculating the working bodies of sprinklers is presented, it can be used by agricultural engineers during their design activities. It is established that it is effective when students first study and analyze the state of agricultural production, for example, during internships, identify shortcomings of technological processes, opportunities for improvement, level of technical support, and then, using theoretical knowledge, mastered methods of engineering calculations, design and construct working bodies of sprinklers. Formulas for determining the radius of the irrigation sector, the maximum angle of the rocker arm at which the nozzle is attached, the total travel time of the rocker arm in both directions, the speed of the liquid in the jet and more are given. The methodological features of functioning of various designs of nozzles of sprinklers are theoretically described. The results of scientific research presented in the article can be used as didactic material in lectures, during laboratory-practical classes, independent work of students, as well as graduate students and scientists at the stage of design and construction of reclamation machines. The main theoretical provisions are recommended to be included in the list of test tasks for assessing the readiness of agricultural engineering for innovative project activities. It is noted that the study of the basics of designing the working bodies of irrigation machines is one of the factors of a holistic conceptual system of protection of soils and water resources. Emphasis is placed on the fact that soil and water resources are important objects and prerequisites for the development of reclamation machines and the formation of special design competencies of agricultural engineers

    • Utilization of tractors and agricultural machinery

      pg(s) 163-165

      Regardless of the length of the period of use of the equipment, due to a change in technology, an increase in maintenance costs or the introduction of new requirements with a change in legislation, the machines become obsolete and are disposed of. The main methods for utilization of tractors and self-propelled agricultural machinery are considered. The equipment necessary for the disposal is also described. The methodology for determining the costs for utilization and the value of the equipment for utilization of the whole machine, element-by-element utilization and utilization after defecting has been supplemented.


    • Assessment of chemical composition of soil solution of water repellent soils from Maritza- Iztok coal basin

      pg(s) 166-168

      The ionic composition and dissolved organic carbon (DOC) in soil solution of four soil profiles, from the area of Obruchishte were analyzed and relationships with soil hydrophobicity were discussed. It was found that the greatest variation and leaching of NO3-, SO4 2-
      and Ca2+ were from the profile of Obruchishte under ash, while of Na+ from Obruchishte under pine. In Obruchishte profile after cereals the highest content of Cl-, PO43- and NO3- were found in the investigated soil solution. No significant correlation was found between the chemical elements and WDPT, except for Obruchishte, stubble. In this profile a significant correlation was found between the Ca2+ and Mg2+ concentrations and WDPT. Significant relationship (R*=0.63, p<0.05) between DOC and WDPT was established only at the experimental profile Obruchishte under ash. Differences in the distribution of soluble organic carbon in soil profiles in our studies is most likely due to the heterogeneity of the geological materials used as a substrate for reclamation of the studied sites

    • The influence of long-term agricultural use of soils of the dry subtropical zone of Azerbaijan on its morphological and agrochemical properties

      pg(s) 169-172

      The aim of the research was to study the influence of natural vegetation and intermediate sowings of fodder crops on the formation in the profile of (WRB, 1998) Gypsisols and Gleyic Calsisols and Irrigated Gypsisols and Gleyic Calsisols soils of the dry-steppe and semi-desert zones of Azerbaijan genetic horizons. It has been established that significant morphological changes are common to the thickness of the humus horizon, the depth of carbonates and agrochemical parameters of the studied soils. Their maximum values in the arable layer are established in Irrigated Gypsisols and Gleyic Calsisols soils under the collection of 3 green mass crops per year from 1 ha: the thickness of the humus horizon increased to 0.25 and 0.27 cm, respectively, humus – up to 2.73 and 3.00%, the amount of absorbed bases – up to 25.71 and 30,80 mg-eq / 100 g of soil, mobile phosphorus – up to 30.9 and 34,00 and exchange potassium – up to 317.3 and 423,1 mg / 100 g of soil. In accordance with the WRB system (2015), Irrigated Gypsisols can be classified – Irragric Cambisols (Protocalcic, Clayic), and Gleyic Calsisols – Irragric Gleyic Calcisols (Calcic, Loamic).

    • Growth analysis of sweet pepper for investigation effect of wood ash and poultry litter on plant

      pg(s) 173-176

      The present study uses the method of soil crops to study the fertilization of the soil, changes in the content and forms of nutrients, the effectiveness of various forms of nutrients introduced by the resulting of soil improver – a mixture of waste – wood ash and poultry litter, by means of a vegetation experiment. Sweet pepper Capsicum annuum subsp. macrocarpum L. was selected for the experiment, variety of gate type – Gold medal 7. The results of the study prove the ability to use soil improvers, good resistance of the leaves to sudden intense changes in climatic conditions. The root systems of all mixtures are well developed and strong, stable with good agrochemical parameters compared to that of the zero sample.

    • Water – yield relationships of lettuce plants for different irrigation strategies

      pg(s) 177-180

      The greatest fresh water user sector is agriculture worldwide. The optimum utilization of current water supplies is necessarily prerequisites particularly in water poor climates. It is almost impossible to obtain economical crop yield without irrigation in those types of environments. In general, vegetables are high water consuming crops and well responses to the adequate soil moisture levels in rooting depths. Correct irrigation program is vital important for reaching target optimal production. The present study aimed to analyze irrigation programs affect on yield and water use efficiency, WUE, of lettuce plant for different growing conditions. In accordance of previous studies, maximum yield was obtained from full irrigation treatment. Lettuce plants were not tolerant wide irrigation intervals e.g. 2 or 3-day ideal for optimal yield and quality. Evapotranspiration, ETc, was highly dependent on lettuce varieties, availability of soil moisture content in root systems as well as climatological factors, and ranged between 413 mm and 208 mm. The planting geometry also had effect on lettuce yield. The irrigation system is important, but the most important issue is proper water management for enhancing crop production. Use of sprinkler or drip irrigation system should be highly recommended for better yield, quality as well as efficient water usages or water savings in vegetable farming under correct irrigation program.

    • Study of the influence of the irrigation regime on the quantity and quality of tomatoes grown in plastic greenhouses

      pg(s) 181-183

      To establish the influence of the irrigation regime on the quantity and quality of tomatoes grown in plastic unheated greenhouses, research was conducted in the experimental field of the Pushkarov Institute in Chelopechene, Sofia. Different irrigation regimes have been tested, keeping from fully satisfying the needs of the crop from water to irrigation with a 20% reduction and a 20% increase in irrigation norms. The control variant is irrigated at 100% realization of the irrigation norm, calculated by (E0) evaporation from a free water surface by an evaporator class “A”.
      It has been established that the reduction of the irrigation norm due to the limited water supply leads to a corresponding reduction of the yield, which is not proportional to the reduction of the irrigation norm.
      The quality of the obtained production – tomatoes determined by the content of dry matter, vitamin “C” and total sugars deteriorates with increasing amount of irrigation rate.

    • Analysis of climatic variability and determination of thermal and pluviometric limits in Albania’s Southwestern Lowland Area (Vlora)

      pg(s) 184-189

      The geographical distribution of plants in ecosystems and the limits of agronomic extention of plants cultivated in different areas are conditioned by the performance and climatic variabilities of these areas.The biological and productive behavior of plants in agricultural systems is determined by climate performance in general and in particular by the two main climatic parameters, temperature and precipitation.Their significant fluctuations, conditioned in recent years by climate change, are evident in the form of risky for agriculture such as prolonged droughts, severe shortages of rainfall, high summer temperatures in the form of heat waves, which further brings the effect of agronomic drought. In the thermal minimums, expressed in the form of frosts, there are observed fluctuations changes creating deviations from the average perennial performance of their occurrence. The study of thermal fluctuations, and in particular the study of the phenomenon of drought and its consequences, it is an important problem especially in areas with high agricultural character. Drought occurs when there is a shortage of rainfall for long periods, registering as a pluviometric deficit. Occurrence variations of this phenomenon are related to the rainfall cycle, but they should be considered in relation to potential climate change, especially in the Mediterranean basin where Albania is located. The study of climate variability and the identification of extreme climate phenomenas as well as the determination of thermal and pluviometric limits can be done through climate monitoring indicators. Albania’s western lowland area and particulary the Vlora area, which is under consideration on this study, is an agricultural area with a great diversity of cropping cultivations. Analyzing the climate behavior of this area will enable the design of suitable cultivation technologies as well as taking measures to minimize the damages to crop production from these factors.

    • Studies to establish evapotranspiration and biophysical coefficients of pears grown in drip irrigation

      pg(s) 190-192

      To determine the total and average evapotranspiration of pears during its cultivation under soil and meteorological conditions in the area of the village of Chelopechene – Sofia, studies were conducted on drip irrigation (KP-4.6 drip trays) of pear plantation of the variety “Hardenponova maslovka”.
      Meteorological conditions during the study period influenced the size and daily average values of culture evapotranspiration.
      The total evapotranspiration for the pear growth period of 536 mm was determined, and the daily values of biophysical coefficients Z, R and Kp were calculated for practical use and design, which depend on the biological features of the crop and the meteorological factors.