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001-es BibID:	BIBFORM063089
Első szerző:	Juhos Katalin
Cím:	Influence of soil properties on crop yield : a multivariate statistical approach / Katalin Juhos, Szilárd Szabó, Márta Ladányi
Dátum:	2015
ISSN:	2300-8725
Megjegyzések:	The aim of the study was to reveal the relationship between soil properties and grain yields in an East Hungarian region in regard to weather conditions. Soil pH, EC, carbonate content, soluble and exchangeable Na+, texture, organic carbon, and nutrient contents were analyzed. Yield data (maize, winter wheat, sunflower) from 10 years were standardized using calculated relative yield and yield variability. Weather conditions were characterized by the Pálfai Drought Index. Hydrological and topographical conditions were characterized by the mean altitude of plots. The ranged pedological variables were analyzed using principal component analysis with Varimax rotation. The principal component analysis showed that three principal components with eigenvalues greater than one explained more than 84% of the variability of soil properties. The multiple stepwise principal regression analysis showed that the mean relative yield was linearly correlated with all the three principal component factors (R2 = 0.49, p<0.01). In droughty years,the sodification, salinization, soil texture, and nutrient contents determined the yields (R2 = 0.30, p< 0.05). In humid years, the lower topographical position, soil organic matter, and nutrient contents were the main limiting factors (R2 = 0.40, p<0.01). Consequently, the variables can effectively explain the yield variability together with other variables as linear combinations.
Tárgyszavak:	Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban principal component regression analysis soilplant relationship weather conditions
Megjelenés:	International Agrophysics. - 29 : 4 (2015), p. 425-432. -
További szerzők:	Szabó Szilárd (1974-) (geográfus) Ladányi Márta
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM067462
Első szerző:	Kaszubkiewicz, Jarosław
Cím:	Determination of soil grain size composition by measuring apparent weight of float submerged in suspension / Jarosław Kaszubkiewicz, Witold Wilczewski, Tibor József Novák, Przemysław Woźniczka, Krzysztof Falińskii, Jerzy Belowski, Dorota Kawałko
Dátum:	2017
ISSN:	2300-8725
Megjegyzések:	A b s t r a c t.Texture is one of the most significant physi-cal properties of soils. Over the years, several methods of its measuring were developed. The paper presents a method for determining the particle size composition of soils, based on the separation of particles in the sedimentation process. Densityof suspension is determined on the basis of apparent weight changes of a float submerged in it. The weight of the float suspended ona thin line, at a given depth in the suspension, is measured witha sensitive piezoelectric dynamometer. The Stokes equation is used to calculate the content of soil fractions with equivalent diameters in the range of 0.001 to 0.1 mm. Digital transmission of results from the dynamometer, the temperature sensor and measurements of the distance defining the depth of immersion of the float to the computer enable calculations of particle size composition to be performed automatically. This paper presents the results of mea-surements of the particle size composition of artificially generated mixtures of ♭silt' and ♭clay'. The results are compared with results obtained with other methods (including the laser method). A high level of repeatability of the results and satisfactory compatibility in relation to the reference pipette method are noted.
Tárgyszavak:	Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban sedimentation particle size composition soil suspension density szemcseösszetétel üledékvizsgálat
Megjelenés:	International Agrophysics. - 31 : 1 (2017), p. 61-72. -
További szerzők:	Wilczewski, Witold Novák Tibor (1973-) (geográfus) Woźniczka, Przemysław Falińskii, Krzysztof Belowski, Jerzy Kawałko, Dorota
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