Winter wheat crop water consumption and its effect on yields in southern Romania, in the very dry 2019-2020 agricultural year

Researches on winter wheat in the south part of Romanian Plain during the dry years 2019 and 2020 have been focused on the crop water consumption issue in excessive conditions of air and soil drought. The wheat crop water consumption in the research sites (Calarasi and Teleorman counties), for the entire vegetation period, autumn – spring – summer, is between 1000 and 1050 m3 of water for each ton of wheat produced. Only in the spring-summer period, the wheat extracts a quantity of about 5960 m3 ha-1, i.e. 851 m3 t-1. The useful water reserve is normally located at about 1500 m3/ha-1, at a soil depth of 0-150 cm. In the spring of 2020, it has been below 400 m3 ha-1, so that at the beginning of May the soil moisture had almost reached the wilting coefficient (WC). Wheat plants have been able to survive the thermal and water shock of late spring - early summer, due to enhanced thermal alternation between air and soil. For a period of about 34 days, this alternation brought the plants 1-1.5 mm water, i.e. approximately 442 m3 ha-1, which allowed the prolongation of the plant’s agony until the rains of the second half of May. Yields have been, depending on the variety, between 1500 and 3000 kg ha-1, in average, covering only 60% of the crop costs. Other measures to save water in the soil have also been proposed in the paper

MANAGEMENT OF THE GREEN WORLD BY PHOTOSYNTHESIS MODELING (REPORT OF THINKING AND COMPARATIVE SYNTHESIS)

Photosynthesis is that primary reaction by which the first molecule of organic matter (glucose) from carbon dioxide and water is produced, in the presence of solar energy, in the form of photons, respectively electrons and protons (light wavelengths). Within 3 billion years, the mineral world has been partially transformed into the living world, including in green world, which works on biochemical synthesis using chlorophyll pigments, carotenoids and others. Today's biochemistry considers photosynthesis as a deterministic process, in which the chemicalmathematical equations of processes are well known, as a result of the thousands of researchers working in some of the most modern laboratories. In this paper, data are given on both the chemistry and the mathematics of the photosynthesis algorithm. Data are also presented on the efficiency of the first process of natural biochemical production at the Earth level, from which it results that the energy entered in the process of biosynthesis of photosynthesis through its acceptors is used in 100% percent, which doesn’t happen with any other energy system. Researchers in quantum physics have observed this anomaly and have come to the conclusion that both the "photosynthesis" form, as well as other biochemical forms take place after a quantum morphogenesis whereby photons enter through the mass of the antenna on multiple paths, depositing as much energy as the system accepts

Research Regarding the Importance of Soil Quality Index (Creditworthiness - CWS) on Wheat Yield and on Soil Conservation in Burnas Plain

The paper intends to present the soil quality effect (CWS), given by the National Institute of Soil Science official creditworthiness marks on the Burnas Plain wheat yield. In this way is created the scientific basis for new technologies (varieties) that are about to provide a better exploitation of the soil and of its characteristics, as well as the influence of biotic and abiotic factors (water, heat) from  Burnas Plain, a significant wheat growing area. There has been found a positive correlation between soil quality and yield. It was also observed that increasing technologies are reducing the differences of production in order to equalize between yields on poorer soils compared to the richest. Therefore, the soil working technologies solves numerous defects of poor or degraded soils. For this, the working capital is decisive and so is the agricultural science well applied

Wheat Production Obtaining Patterns according to the Aridity Index ( AR ) , Soil Creditworthiness ( CWs ) and Technological Processes Intensity ( TPI)

The present study aims to present the effect of aridity index (AR )  calculated by the UNEP version, of the quality of soil       (CWs) , given by the official creditworthiness marks of the National Institute of Soil Science and of the agricultural intensity degree  ( TPI )  at var ious levels of agricultural exploitation over the wheat yield in Romania. That creates the scientific basis for new technologies, which will be able to better exploit the water, so precious for the semiarid areas where wheat grows. A negative correlation between AR and the average wheat yield in the last 10 years and a positive one between soil quality and production were found

Management Problems of Ecological Reconstruction of Soils from Burnaz’ Plain and

More than 5 millions hectares of arable land from the total of 9 millions arable land have suffered, in the last 40 years, strong phenomena of ecological degradation due to the excess of works with the plow and to incorrect use of inputs (fertilizers with nitrogen and pesticides). The quantity of humus was reduced by up to 60%, while the biomass from inside the soil decreased 10 times. In this paper is described an ecological reconstruction model of a chernozem soil from the Burnaz Plain, Alexandria area, starting from the tillage system modification on an optimized crop rotation with ameliorative plants (peas, soy, wheat, rape, corn, sunflower) and by introducing into the soil a quantity of up to 4 tonnes/ha residual organic matter associated with activating biocomposts. The results obtained have led to the very significant change of soil’s physical, biological and biochemical properties. The soil compactity was reduced of almost 7 times on the hardpan area, the amount of water held in soil has been improved by over 4 times, the biological activity of soil has increased more than 5 times and the level of premium wheat production has increased more than 3,5 times, as well as its quality (minimum 15% protein)

Instrumentation development for wall shear-stress applications in 3D complex flows

In the turbomachines field, friction losses are intensively studied due to their important influence in the overall efficiency of the machine. The parameter helping in quantifying these friction losses is the wall shear-stress. Its role is essential for the qualification of the boundary layer separation tendency and the losses prediction. Thus, the first aim of this PhD is to characterize the boundary layer development, in the cone of the Francis turbine. Afterwards, in the second part of this study, a new multidirectional wall shear-stress sensor is designed, manufactured and tested for the turbomachines applications. To develop this knowledge and the tools for flows prediction in the draft tube, EPFL joined major manufacturers in the context of the European initiative EUREKA project n° 1625. In the first part of the thesis, an experimental campaign is leaded in the cone of the nq 92 Francis turbine, to characterize the wall stress, using the hot-film technique. 6 operating points were investigated, covering a large operating range – from 70% to 110% from best efficiency point flow rate. For this specific draft tube, the efficiency characteristic has a sever drop, close to the best efficiency point, and the wall shear stress evolution in this region is pointed out. The calibration and measurement procedures are exposed and the accuracy study is performed. The evolution of the wall shear-stress steady values related to the spatial position of sensor – 16 positions were explored – and to the corresponding operating point is analyzed. A boundary layer separation tendency for the part load operating points is pointed out, as well as the bend influence on the spatial evolution of the wall shear-stress. These results were used to validate numerical calculation in the draft tube. Additional LDV measurements combined with the wall shear-stress results allowed to reconstruct the boundary layer. The best fit for representing the boundary layer is obtained with a composite power law. However the 3D boundary layer is complex and a profound knowledge is needed. From the unsteady point of view, in the runner outlet section, the amplitude of the wall shear-stress fluctuations obtained synchronous with the runner's rotating frequency is predominant. For the partial load operating points, the main fluctuations magnitude is obtained for the rope passage frequency and its amplitude depends on 2 parameters: the σ value and the proximity of the rope to the wall. To increase the knowledge for the boundary layers in turbomachines, it is necessary to explore fully 3D unsteady boundary layers, both in the fixed and rotating parts of the machine. Thus a multidirectional sensor with specific requirements is needed for the turbomachines application: a miniature hot film probe, which can be implemented in the complex geometry of the turbines, a multidirectional one, to take into account the complex character of the flow, mainly the strongly 3D flow, a sensor with a sensitivity and dynamic, allowing to obtain the main flow unsteady characteristics (guide vanes wake, runner blades wake, rope frequency, turbine-circuit interaction frequency, etc.), a good electrical isolation between the surface of the probe, which comes in contact with the water, and with the hot-film support. In this way, the second aim of this PhD becomes the design and development of a new multidirectional wall shear-stress sensor for turbulent boundary layer research for turbomachines applications. The development of the new multidirectional sensor implies technological developments using microtechnology, as MEMS offers opportunities for developing and manufacturing sensors with regard to complex applications, allowing, in the same time, a high accuracy at low cost. The new sensor represents a bridge between 2 different disciplines: micromechanical technology and fluid mechanics. Its concept is based on the heat transfer generated by a hot film with a general top-area of 1.12 × 0.1 mm and a thickness of 110 nm. The film, in platinum, is maintained at a constant temperature, of 65°C, by a feed-back electronic. Key process steps in fabrication of the new device are lithography, bulk micromachining, thin film deposition, surface micromachining, lift-off and chemical mechanical polishing. The manufacturing of new miniature wall shear-stress sensor is based on a combination of these techniques. A specific development is performed for the achievement of an insulating surface to reduce the heat conduction between the hot film and the sensor body, on which the hot film is deposed. This surface is obtained by manufacturing silicon dioxide layers, of 4 µm, by DRIE technique, in order to create high-aspect-ratio silicon pillars, which are then oxidized and/or refilled with LPCVD oxide or nitride. One of the major criteria for the trenches filling was the surface planarity at the end of the refill. 2 parameters are optimized: the thickness and the silicon pillars arrangement. Thermal numerical computations were carried out using Ansys and they allowed the achievement of the optimum thermal isolation thickness between the heated structures and the surrounding structures. During the development of the new wall shear-stress probe, the main topics, achievements and contributions can be categorized into: design of a new wall shear-stress sensor, fabrication steps development, validation and optimization of the design, numerical simulations of the thermal behavior of the heated-films, manufacturing of the new device. The new sensor is characterized in terms of time response, electrical insulation between the surface of the probe, which comes in contact with the water, and the hot-film, and reliability. The sensor is robust, with a good sensitivity for water measurements. The main improvements, which make the current device distinct, are its design for a directional response for 3D turbulent boundary layer study and the insulating surface for substantially reduction of the heat losses by conduction between the film and the surrounding substrate

NDMI USE IN RECOGNITION OF WATER STRESS ISSUES, RELATED TO WINTER WHEAT YIELDS IN SOUTHERN ROMANIA

In the south part of Romania, during 2016-2021, research was conducted on the water stress of wheat crop, represented by 7 varieties of premium genetics wheat, i.e. high in protein and gluten. The analysis of NDMI (Normalized Difference Moisture Index) showed that, during the research period, the plants benefited from an average index of 0.21 units, placing the area in the category of those that offer a moderate size of vegetation and a medium stress for water. Under these conditions, the average wheat yield was 4,413 kg/ha, i.e. less than 50% of the varieties potential. The annual wheat variation of NDMI (170 days, spring-summer) ranged from -0.015 units in 2020, when yield was below 2,000 kg/ha, to 0.356 units in 2021, when due to phytosanitary stress, the average yield was of 5,512 kg/ha. Rest of the years had intermediate values, in each of them the water stress being present either in spring or in summer. The correlation between the water stress and the obtained yields was represented as a polynomial function, statistically assured. Average yields of 50% of the variety potential can be obtained at stresses of not less than 0.1-0.2 NDMI units. In this regard, it is necessary to rethink technologies, especially on recalculating the level of some inputs, which in conditions of pronounced water stress are only partially used by plants

Wheat Varieties Resistance to the Biotic Stresses Generated by Diseases - Main Factor of Agro Ecological Economy

For wheat crop, in 2013-2014 a comeback of resistant strains of extremely harmful diseases such as yellow rust (Puccinia striiformis) and fusarium (Fusarium spp.) was observed. By preventing the absorption of solar energy and limiting  the yield, by average, with 30-40% for the untreated pesticide version, entropy in wheat increased significantly. Entropy increase was also supported by the necessity to double the number of treatments from 1-2, to 3-4 in this special years. Currently there are no plant protection products that can control the wheat pathogens 100%. Thermodynamic biosystem reconstruction can be achieved only by obtaining and using resistant or immune varieties to the whole complex of wheat diseases. In the wheat crops in Romania, we can meet at least 13 diseases that, together or separately, may cause 15% damages even under treatment, taking into account the phenomena of resistance. Entropy on the food chain plant - animal - human or directly plant - human can also be increased by induction of mycotoxins (DON) in useful productions, which are extremely dangerous for food safety. All these have significant economical and environmental negative effects