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  • Evaluation of the correlations between the normalized difference vegetation index (NDVI) and yield in a seasoning paprika (Capsicum annuum L. var. longum) stand
    45-49
    Views:
    242

    The aim of our examination was to evaluate the correlations between the normalized difference vegetation index (NDVI) and yield, as well as to examine the possibility of yield estimation basedon NDVI in a seasoning paprika population.

    Significant correlations were observed during the examination of the correlation between NDVI and yield. Furthermore, it was concluded that yield can be estimated with a 6.6–8.3% mean error based on the regression equations. No significant difference was shown between the error of estimations performed with various regression types and that of the estimations performed at various dates. For this reason, the identification of the optimum estimation method and the determination of the optimum date for estimation call for further examinations.

  • The effect of water supply and crop year on the yield potential of sweet maize (Zea mays L. convar. saccharata Koern.) hybrids with different genotypes
    203-210
    Views:
    156

    The successfulness of crop production is significantly affected by not only the the average yields that provide cost effectiveness, but also the success of striving for yield safety, therefore, varieties and hybrids tolerant to environmental stress factors are worth being included into the sowing structure. Our aim was to further the decision making of producers in prepaering the right sowing structure by the evaluation of sweet maize hybrids’ tolerance to excess rainfall.
    We performed our examinations in an extremely wet year (2010) on chernozem soil on three sweet maize hybrids (GSS 8529, GSS 1477, Overland) in 12 replications. Comparing the yields of 2010 with those that can be expected under optimal rainfall conditions, we showed that the examined hybrids react to the amount of rainfall higher than their needs with yield depression. The excess rainfall tolerance of the examined hybrids is different in the case of each hybrid.

  • The impact of environmental factors on the measurement of the normalized difference vegetation index
    141-147
    Views:
    119

    The level of nitrogen supply of a plant population can be quickly measured with non-destructive optical measurement devices and the differentiated determination of nitrogen shortage and the replenishment of nitrogen can also be carried out. The level of nitrogen supply is based on the fact that the chlorophyll content of crops is in close correlation with nitrogen content and that the amount of chlorophyll can be easily measured on the basis of the light absorption of chlorophyll molecules. The successfulness of optical measurements can be influenced by the change of weather  parameters; therefore, it is important to know the correlations between measurement results and weather parameters when it comes to practical use.
    The GreenSeeker Model 505 measurement device determines the relative chlorophyll content in the form of the Normalized Difference
    Vegetation Index (NDVI) calculated on the basis of the intensity of the reflected red and infrared rays of light from the crop population. The measurements were performed in alfalfa population with 10 replications at five measurement heights and four measurement times. The weather parameters were measured by a weather station located in the middle of the alfalfa population and the correlations between the meteorological data and the NDVI values were examined. During the statistical evaluation of the results, it was established that the NDVI measurement is primarily influenced by the relative humidity of the air, secondly by air temperature and thirdly by wind speed. Relative humidity was in strong correlation with the NDVI values which were also influenced by the measurement height and time. Regression was not significant in the case of 20 cm  measurement height, but the measurements above 40 cm height showed significant correlations. The correlation was shown to be strong at each measurement time, but the influence of humidity was the lowest at 11:00 and 14:00. 

  • Comparative analysis of soil analysing datas on different sempling-plots
    85-90
    Views:
    64

    Hibrid maize is cultivated on larger plots, therefore the sown areas of hibrid maize are heterogeneous from a pedology aspect. Heterogenity causes problems during tasseling, chemical plant protection and harvest. The heterogenity of sown areas can be compensated by fertilization which is based on soil analysis. We carried out research into change of the soil on four soil types from 1987 to 2005.
    There were no significant changes in pH, hydroiodic acidity, CaCO3-content, humus-content on meadow chernozem soil. We detected equalization of salin content in the examined soil layers. There were no significant changes in the measured values on chernozem meadow soil and solonetz meadow soil in 2005. We discoverd equalization of saline content on chernozem meadow soil, but the changes were not as obvious as the changes on meadow chernozem soil. We found salinization in the 30-60 cm soil layer on type meadow soil that may be due to water movement.

  • Opportunities of delineating inland waters and soil moisture with remote sensed data
    95-98
    Views:
    106

    The methodology for delineating water bodies on multispectral remote sensing imagery was examined and evaluated. A supervised approach is tested with the aim to accurately detect inland water, moisturised soil surface and swampy patches on the Landsat TM 7 scene. The goal of this research is to investigate whether the application of remote sensing image interpretation could further refine the possibilities of future soil conductivity measurement research. The methodologies used were the application of supervised classification algorithms based on the training data collected in the area. The achieved overall classification accuracy value of 83.0795% suggests that the methodology could be used as a successful strategy to incorporate remote sensing data interpretation into soil conductivity measurement planning and application. The main conclusion that can be drawn is that processing of multispectral data with further refinement of the presented methodologies can led to very useful outcomes for environmental measurements.

  • Soil analysis as the foundation of precision nutritive supply in the Hajdúszoboszló region
    141-148
    Views:
    71

    Larger cultivated plots are heterogeneous from a pedological aspect. Heterogeneity causes problems during fertilization and harvest. The heterogeneity of cultivated areas can be compensated by fertilization which is based on soil analysis. We carried out research into the changes of the soil on three soil types, from 1966 to 2006, on the cultivated areas of Hajdúszoboszló.
    There were no significant changes in pH on chernozem meadow soil and meadow chernozem soil, but the pH increased in 0-30 cm layer on type meadow solonetz soil. The saline content decreased in every examined soil type. Decrease was the largest on meadow solonetz soil. Decline of humus content was the largest (0.95%) on chernozem meadow soil, and the smallest (0.39%) on meadow chernozem soil. The nitrogen content decreased with 528 ppm in the 0-30 cm layer on chernozem meadow soil, and decreased by 186 ppm on meadow solonetz soil. Phosphorus and
    potassium content increased in every examined soil types. Rise of phosphorus content was 188.9 ppm in the 0-30 cm layer on meadow chernozem soil. The potassium content rose by 153.7 ppm on this soil type. Phosphorus content increased with 70.8 ppm, and potassium content increased by 57.6 ppm from 1966 to 2006.

  • Statistical comparison of soil analysing results of chernozem soils
    93-99
    Views:
    119

    The soil fertility was degraded as a result of unreasonable tillage, therefore the application of site-specific nutrient replacement is necessary. It is essential for the application of precision fertilization to know the location, extension, soil properties and nutrient-supply of the different soil types of
    cultivated areas.
    We collected soil samples from 580 hectares of land in 2006. Soil samples were collected from every 5 ha in 30 and 60 cm depths during Spring from 20.05.2006 to 12.06.2006 and again in Autumn from 09.19.2006 to 02.10.2006. Soil samples were analysed at the Department of Agricultural Chemistry and Soil Science of DE-ATC.
    The two examined soils are slightly calcareous, weakly saline, poor in zinc. The calcareous chernozem soil is slightly acid, the content of humus, nitrogen, phosphorus and potassium is medium in this soil. The meadow chernozem soil is slightly alkaline, and properly supplied with humus and potassium, and middling supplied with nitrogen and phosphorus. The meadow chernozem soil is more heterogenous in soil plasticity, lime, saline, nitrogen phosphorus and potassium content and less heterogenous in pH and zinc content than the calcareous chernozem soil.
    Standard deviation of measured values in pH, soil plasticity, humus and nitrogen content significantly differ between the examined soil types. The soil plasticity, pH, humus, nitrogen and zinc content significantly differ among calcareous chernozem soil and meadow chernozem soil, but the difference in phosphorus content can be statistically proven only in case of Spring soil sampling.