Kristina Lekavičienė

Dr. Kristina Lekavičienė

Department of Agriculture Engineering and Safety, Vytautas Magnus University Agriculture Academy, Kaunas, Kauno Miestas, Lithuania
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2018 in Science of The Total Environment
Verified
Journal Article
Closed access
Vilma NaujokienėVilma Naujokienė
Vilma Naujokienė
EŠEgidijus Šarauskis
Egidijus Šarauskis
Kristina LekavičienėKristina Lekavičienė
Kristina Lekavičienė
AAAida Adamavičienė
Aida Adamavičienė
SBSidona Buragiene
Sidona Buragiene
ZKZita Kriauciuniene
Zita Kriauciuniene

31 January 2023 in Agriculture
Verified
Journal Article
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TJTadas Jomantas
Tadas Jomantas
Kristina LekavičienėKristina Lekavičienė
Kristina Lekavičienė
Dainius SteponavičiusDainius Steponavičius
Dainius Steponavičius
AAAlbinas Andriušis
Albinas Andriušis
EZErnestas Zaleckas
Ernestas Zaleckas
AKAurelija Kemzūraitė
Aurelija Kemzūraitė
Pesticide spray drift has been a worldwide concern in terms of potential environmental pollution and ecosystem damage. This study defined the main drift reduction agent (DRA) characteristics that help to understand the drift formation process in agricultural spraying. Seven various DRAs and water were evaluated. Three solutions were created based on the following materials: calcium dodecylbenzenesulfonate, benzenesulfonic acid, C10-13-alkyl derivatives, and calcium salt. Drift measurements were performed by means of the open circuit-type wind tunnel and in the field under conditionally controlled conditions. Air-injector flat spray nozzles and standard flat spray nozzles were used during trials. The spray pressure was 4.0 bar. Solutions were sprayed at different wind speeds (from 2 m s−1 to 10 m s−1, increasing every 2 m s−1). Studies have shown that wind speed and nozzle design have the greatest influence on spray drift. For all DRA solutions studied, the standard flat spray nozzles resulted in ground spray drift, both in the wind tunnel and in the field, which was about two times higher than that of air-injector flat spray nozzles. The spraying of water and all DRA solutions with the air-injector flat spray nozzle showed that all new solutions statistically significantly reduced the drift both in the tunnel and in the field. Ground-drift studies in the wind tunnel showed a trend towards a less intense drift reduction in DRA droplets with increasing wind speed. With DRA7e, the drift can be reduced by up to 56% (at a wind speed of 4 m s−1) and up to 30% (at 10 m s−1). The effect of the solutions on the reduction in spray drift is significantly lower when spraying with standard flat spray nozzles. Spray drift can then be reduced by up to 30% (at a wind speed of 4 m s−1) and up to 12% (at 10 m s−1) for DRA7e.

30 August 2021 in Sustainability
Verified
Journal Article
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EŠEgidijus Šarauskis
Egidijus Šarauskis
Vilma NaujokienėVilma Naujokienė
Vilma Naujokienė
Kristina LekavičienėKristina Lekavičienė
Kristina Lekavičienė
ZKZita Kriauciuniene
Zita Kriauciuniene
Egle JotautieneEgle Jotautiene
Egle Jotautiene
RZRaimonda Zinkevičienė
Raimonda Zinkevičienė
Granular organic fertilizers have been increasingly used in agriculture due to the longer delivery of nutrients to plants and the milder impact on the environment. The aim of this study was to determine the energy, environmental and economic efficiency of granular and non-granular organic fertilizers. Four technological scenarios of organic fertilizer use were used for comparative assessment: (1) manure fertilization (16.0 t ha−1), (2) manure fertilization (30.0 t ha−1), (3) manure pellet fertilization (2.0 t ha−1), and (4) fertilization with meat and bone meal pellets (0.7 t ha−1). Experimental studies using the mass flow method of laser spectroscopy were performed to evaluate the comparative environmental impact of granular and non-granular organic fertilizers. Economic assessment was performed for mechanized technological operations of loading, transportation and distribution of organic fertilizers, estimating the price of aggregates used and fuel consumed, the costs of individual technological operations and other indirect costs. The results showed that for mechanized technological operations, when fertilizing with granular organic manure and meat and bone meal fertilizer, energy consumption is 3.2 to 4.0 times lower compared to fertilization with manure. The average ammonia (NH3) emissions from granular organic fertilizers were found to be six times lower than from non-granular organic fertilizers. The lowest costs for mechanized works were incurred when using meat and bone meal pellets, the highest economic benefits of organic fertilizers by elements was when using manure 30 t ha−1, and the highest costs for organic fertilizers were incurred when using manure pellets.

14 May 2019 in Soil and Tillage Research
Verified
Journal Article
Closed access
Kristina LekavičienėKristina Lekavičienė
Kristina Lekavičienė
EŠEgidijus Šarauskis
Egidijus Šarauskis
Vilma NaujokienėVilma Naujokienė
Vilma Naujokienė
SBSidona Buragiene
Sidona Buragiene
ZKZita Kriauciuniene
Zita Kriauciuniene

8 March 2023 in Plants
Verified
Journal Article
Open access
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Justinas AnušauskasJustinas Anušauskas
Justinas Anušauskas
Dainius SteponavičiusDainius Steponavičius
Dainius Steponavičius
Kestutis RomaneckasKestutis Romaneckas
Kestutis Romaneckas
Kristina LekavičienėKristina Lekavičienė
Kristina Lekavičienė
EZErnestas Zaleckas
Ernestas Zaleckas
Eglė SendžikienėEglė Sendžikienė
Eglė Sendžikienė
The heavy use of mineral fertilizers causes imbalances in the biological processes that take place in soil. Therefore, it is necessary to develop more effective fertilizers or fertilizer complexes that ensure agricultural productivity and soil conservation. There is currently a lack of knowledge regarding the effectiveness of biologically enriched, complex mineral fertilizers for spring barley fertilization. The hypothesis of this study was that bacteria-enriched (Paenibacillus azotofixans, Bacillus megaterium, Bacillus mucilaginosus, and Bacillus mycoides), complex mineral fertilizers (N5P20.5K36) have significant impacts on the yield and potential for economic use of spring barley. Experimental studies were carried out for three years (2020–2022) with sandy loam soil in southern Lithuania. Four different spring barley fertilization scenarios (SCs) were investigated. In SC-1 (control), complex mineral fertilizer (N5P20.5K36) was not applied. In the other SCs, spring barley was sown with a drill and fertilizers were incorporated locally during the sowing operation: fertilization scenario SC-2 used 300 kg ha−1, SC-3 used 150 kg ha−1 preceded by a bacteria-inoculated complex mineral fertilizer (N5P20.5K36), and SC-4 used 300 kg ha−1 with the same bacterial complex. The results showed that the bacterial inoculant increased the efficiency of the mineral fertilizer and had an effect on plant growth in barley. For three consecutive years in the same plots, the bacterial inoculant showed significant positive effects on grain yield (changes of 8.1% in 2020, 6.8% in 2021, and 17.3% in 2022 between SC-2 and SC-4). Comparing the several different fertilizer scenarios from an economic point of view, it was observed that the highest profit per hectare was obtained with SC-4 in all three years of the study. Comparing SC-4 and SC-2, an increase of 13.7% was observed in 2020, followed by 9.1% and 41.9% in 2021 and in 2022, respectively. This study will be useful for farmers, biological inoculant manufacturers, and scientists researching the effectiveness of biological inoculants for growing agricultural crops. We found that it is possible to increase the yield of barley (7–17%) using the same rate of mineral fertilization by enriching it with bacterial inoculants. Further studies should be conducted to determine the effects of the bacterial inoculant on crop yield and soil over a period longer than 3 years.

16 December 2022 in Processes
Verified
Journal Article
Open access
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MKMarius Kazlauskas
Marius Kazlauskas
EŠEgidijus Šarauskis
Egidijus Šarauskis
Kristina LekavičienėKristina Lekavičienė
Kristina Lekavičienė
Vilma NaujokienėVilma Naujokienė
Vilma Naujokienė
Kestutis RomaneckasKestutis Romaneckas
Kestutis Romaneckas
Dainius SteponavičiusDainius Steponavičius
Dainius Steponavičius
Wheat is among the world’s most important agricultural crops, with winter wheat accounting for approximately 25.5% of the total agricultural crop in Lithuania. The unchangeable goal of crop production is to achieve good and economically beneficial crop yield, but such efforts are often based on conventional agrotechnological solutions, and excessive fertilization, which is uneconomical and negatively affects the soil, the environment, and human health. In order to produce a rich and high-quality cereal crop, scientists and farmers are increasingly focusing on managing the sowing and fertilization processes. Precision technologies based on spectrometric methods of soil and plant characterization can be used to influence the optimization of sowing and fertilizer application rates without compromising crop yield and quality. The aim of this study was to investigate the effect of site-specific seeding and variable-rate precision fertilization technologies on the growth, yield, and quality indicators of winter wheat. Experimental studies were carried out on a 22.4 ha field in two treatments: first (control)—SSS (site-specific seeding) + URF (uniform-rate fertilization); second—SSS + VRF (variable-rate precision fertilization) and 4 repetitions. Before the start of this study, the variability of the soil apparent electrical conductivity (ECa) was determined and the field was divided into five soil fertility zones (FZ-1, FZ-2, FZ-3, FZ-4, and FZ-5). Digital maps of potassium and phosphorus precision fertilization were created based on the soil samples. Optical nitrogen sensors were used for variable-rate supplementary nitrogen fertilization. The variable-rate precision fertilization method in individual soil fertility zones showed a higher (up to 6.74%) tillering coefficient, (up to 14.55%) grain yield, number of ears per square meter (up to 27.6%), grain number in the ear (up to 6.2%), and grain protein content (up to 12.56%), and a lower (up to 8.61%) 1000-grain weight on average than the conventional flat-rate fertilization. In addition, the use of the SSS + VRF method saved approximately 14 kg N ha−1 of fertilizer compared to the conventional SSS + URF method.