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  • Study of factors controlling the amount of 0.01 M CaCl2 extractable Norg fraction
    437-449
    Views:
    181
    The use of new methods describing the “readily available” nutrient content of the soil is spreading on a global scale. The 0.01 M CaCl2 extractant is a dilute salt solution in which the easily soluble inorganic (nitrate-N and ammonium-N) and organic N fractions, P, K and micronutrients are also measurable. The 0.01 M CaCl2 has been tested in the University of Debrecen, Institute of Agricultural Chemistry and Soil Sciences since the 90’s. The results of the researches related to organic N fraction, performed in the last decades, and the results of the present study (originating from the long-term experiment of Karcag, 2007–2009) can be concluded as follows:
    The measurement of easily soluble and oxidizable organic nitrogen (Norg), besides inorganic fractions, could improve the nutrient management.
    The amount of the Norg fraction is determined by the soil conditions, therefore it is considered to be a site-specific parameter.
    Management practices and cropyear affect the amount of Norg as well. The present research confirmed that, the effect of fertilization on the amount of Norg can be explained by the changing of the yield (related to total biomass production), while the effect of cropyear is related to the differences in mineralization circumstances and yield as well.
    The measurement of the Norg fraction is increases the accuracy of N-supply, therefore it could prevent the environmentally harmful excess N application as well.
  • The possibility of use of the 0,01 M CaCl2 and Baker- Amacher extractants for the determination of plantavailable potassium
    7-15
    Views:
    71

    The Hungarian fertilizing recommendation systems use AL soil test for the evaluation of potassium supply. The 0.01 M CaCl2 is a definitely milder extractant, it extracts the easily soluble and exchangeable potassium amount. Its European introduction was already taken into consideration in 1994. The research project on this topic is started in several european countries, also in Hungary at the Department of Agricultural Chemisty of Agricultural University of Debrecen. Another advantage this multielement method is that the different element-ratios can also be calculated.
    The Baker-Amacher extractant’s principle is that it contains a known amount of K, P, Mg in the CaCl2 solution. During the soil extraction adsorption and desorption process take place, so the adsorption or desorption can be calculated from the original and the final concentrations.
    In this paper we introduce the results of comparing analysis of the samples (n=630) from Soil Information and Monitoring System. Our aim was to measure the use of new extractants beside conventional extractant (AL) for the evaluation of K-supply would be reasonable.
    It can be stated that there is a medium close relationship (r=0.75) between AL-K and 0.01 M CaCl2-K. My calculations confirmed the results of  former examinations, and proved that the two extractants don’t extract and change the same rate of K-fractions. We found that regression  between 0.01 M CaCl2 and AL depend on texture classes, pH classes, amount of lime, and organic matter content of soils.
    Comparing the relations between AL and Baker-Amacher we find relatively loose correlation (r=0.45). We stated that there are K-fixing soils among soils considered to be well supplied with potassium by AL. This might be caused by the high amount of mineral clay and the quality of mineral clay. We stated that the dK averages show that the Hungarian nutrient-supply categories characterize generally well K-supplement of soil.
    It can be stated that it would be necessary to use new extractants to specify evaluation of plant available K. We found that the 0.01 M CaCl2 and Baker-Amacher extractants could complete usefully the AL procedure and could help effective potassium fertilization.

  • The effect of water-stress on the mineral nutrition of fruit plantations
    187-192
    Views:
    83

    Besides agro-techniques the climatic conditions play an important role in agricultural production. Weather extremes are
    significant hazards to many horticultural regions all over the word. It has a profound influence on the growth, development and yields of a
    crop, incidence of pests and diseases, water needs and fertilizer requirements in terms of differences in nutrient mobilization due to water
    stresses. Nowadays, the weather extremes cause more and more problems and significant hazards to many horticultural regions in Hungary.
    The aim of this study is to explore the problems of nutrient uptake followed from climatic anomalies and response it. In this study
    we focus on water supply problems (water-stress).
    Reviewing the effects and nutrient disorders caused by climatic anomalies, the following statements can be taken:
    · Nutrient demand of trees can be supplied only under even worse conditions.
    · The most effective weapon against damage of climatic anomalies is preventative action.
    · Proper choice of cultivars, species and cultivation should provide further possibilities to avoid and moderate the effects of
    climatic anomalies.
    · Fruit growing technologies especially nutrition should be corrected and adjusted to the climatic events as modifier factors.
    · The role of foliar spraying, mulching and fertigation/irrigation is increasing continuously.
    · Urgent task of the near future is to correct and adjust the tested technologies of fruit growing according to these climatic events as
    modifier factors.
    Optimal nutrient supply of trees decreases the sensitivity for unexpected climatic events. To solve these problems supplementary, foliar
    fertilization is recommended, which adjusted to phonological phases of trees. Moreover, mulching is regarded as an excellent water saving
    method.

  • Studies of the influences of different N fertilizers and Microbion UNC bacterial fertilizer on the nutrient content of soil
    134-140
    Views:
    59

    A field experiment was conducted to examine the effects of different nitrogen fertilizers in combination with bacterial fertilizer on
    nutrient uptake of horseradish and plant available nutrients of the soil. Three different N fertilizers, ammonium-nitrate, urea and calciumnitrate
    (116 kg ha-1 N) in combination with Microbion UNC bacterial fertilizer (2 kg ha-1) were applied as treatments in a randomized
    complete block design in three replications. In this paper we presented the results of soil measurements. The soil of the experimental area
    was chernozem with medium sufficiency level of N and P and poor level of K.
    Our main results:
    The amount of 0.01M CaCl2 soluble inorganic nitrogen fractions, NO3
    --N and NH4
    +-N and also the quantity of soluble organic-N were
    almost the same in the soil. N fertilizers significantly increased all the soluble N fractions. The amount of NO3
    --N increased to the greatest
    extent and the increase of organic N was the slightest. We measured the largest CaCl2 soluble NO3
    - -N and total-N contents in the plots
    treated with ammonium-nitrate, the largest NH4
    +-N in the plots treated with calcium-nitrate and the largest organic-N fraction in plots
    treated with urea.
    Bacterial inoculation also increased both soluble inorganic nitrogen forms and also total-N content of soil compared to the control. In
    the case of combined (artificial and bacterial fertilizer) treatments we measured lower NO3
    --N, organic-N and total-N compared to the
    values of plots having only nitrogen fertilizer treatments. On the contrary in the plots with combined treatments the CaCl2 soluble NH4
    +-N
    content of soil in more cases were higher than that of values with artificial fertilizer treatment.
    As a function of calcium-nitrate application increased AL-P2O5 and AL-K2O values were measured compared to control. Microbion
    UNC supplement of calcium nitrate yielded also increase in AL-P2O5 and AL-K2O values, till then supplement of ammonium-nitrate fertilizer
    yielded a decrease in these values compared to the control.
    All nitrogen fertilizers resulted in a significant decrease in AL-Mg content of soil compared to the control. Nevertheless bacterial
    fertilizer increased AL-Mg values in any cases.

  • Effects of long-term K fertilization and liming on the extractable and exchangeable K contents of a Haplic Phaeosem soil
    141-145
    Views:
    30

    Effects of regular K fertilization and liming on the easily extractable K content of a Haplic phaeosem soil determined in 0.01 M CaCl2
    and AL (traditional method in Hungary) were examined in the B1740 type of the National Uniformed Long-Term Fertilization Experiments
    at Karcag.
    Close correlation (r=0.95) was found between the 0.01 M CaCl2 and ammonium lactate - acetic acid (AL) extractable K contents of
    soils.
    K fertilization increased the amount of 0.01 M CaCl2 and AL extractable K significantly. Liming had different effects on the amounts of
    K extracted by these two methods. Liming increased the amount of AL-K and decreased the amount of CaCl2-K. CaCl2 extractable K was in
    close correlation with the relative amount of exchangeable K content of the soil (K%) and the agronomic K balance. The results of regression
    analysis confirmed that the CaCl2-K characterized K% and the AL-K related to the absolute amount of exchangeable K.
    On the basis of the presented results it can be stated that the 0.01 M CaCl2 is able to detect not just the increase of easily extractable K
    caused by fertilization and liming but the changing of the rate of the relative amount of exchangeable K.

  • The effect of long-term fertilization on phosphorus content determined in different soil extractants on meadow chernozem soil
    7-11
    Views:
    66

    The 0.01 M CaCl2 universal extractant is known all over Europe since the 90’s. During my research, I exam the phosphorus content determined in 0.01 M CaCl2 of the samples originated from the B 17 National Uniformed Long Term Fertilisation Trials in the experimental site Karcag, in the 40th year of the experiment. Relationships between the CaCl2-P and the AL-P content of the soil, the average yields, and the phosphorus balance of the
    2006/2007 year were studied. From the results of the study it was concluded as follows:
    – Correlation was close (r=0.68-0.7) between the AL-P and CaCl2-P. This is in accordance with the results of previous experiments in Hungary and other countries.
    – My studies confirmed that the calcium-chloride method indicates well the deficiency and the surplus of plant available phosphorus. In case of different degrees of negative balance, the amount of CaCl2 extractable phosphorus showed no changes, or decreased, and in case of positive balance it increased exponentially by the long-term effect of P rates.
    – The 120 and 180 kg ha-1 rates resulted in significant increases in the amount of CaCl2-P according to the control and treatments that are not fertilized with phosphorus. The 60 kg ha-1 rate didn’t result any increase as it didn’t meet the phosphorus requirement of winter wheat, and presumably the P-balance was negative in the earlier years as well.
    – It can be stated that the 0.01 M CaCl2 was able to assess the deficiency and the excess of phosphorus causing negative impacts on environment as well.

  • The effect of long-term fertilization on the 0.01 M CaCl2 extractable nutrient content of a meadow soil
    73-79
    Views:
    93

    During my research, I studied the 0.01 M CaCl2 extractable NO3--N, NH4+-N, Norg, P and K contents of the soil samples originated from a long term fertilisation trial in the experimental site Hajdúböszörmény. Relationships among the soil nutrient contents, the agronomic nutrient balances of the 2009 year, and fertilization were studied. 
    From the results of the study it was concluded as follows:
    – Fertilization significantly increased the CaCl2 extractable NO3--N, NH4+-N, and K contents of soil.
    – Norg fraction increased as a function of the increasing yield. Hence, it can be assumed that the greater the produced yield, the more the stubble and root residues remain on the arable land. These organic residues can result significant increase in the Norg content of soils.
    – The CaCl2 extractable P and K contents were compared with the calculated P and K limit values. According to these, the experimental soil has a good phosphorus and lower potassium supply capacity. These results are in accordance with the results of the conventional Hungarian fertilization recommendation system.
    – It can be stated that the 0.01 M CaCl2 is able to determine not just inorganic N forms but Norg fraction as well that characterize the easily mineralizable nitrogen reserves. The results proved that AL-P and -K (ammonium lactate acetic acid, traditional Hungarian extractant) are in good agreement with the P and K reserves, but it is important from the aspect of environmental protection and plant nutrition to measure the easily soluble and exchangeable K-, and P-contents of soil. 0.01 M CaCl2 method is recommended for this.

  • Changing of some parameters of the soil-plant system as an effect of different composts
    262-266
    Views:
    80

    Composting is an alternative way for practicing site-specific and environmental friendly plant nutrient supply. Our aim was to study the effect of different composts on plant and soil system. 
    Pot experiment with acidic sandy soil blended with three composts in five (0%, 5%, 10%, 25% and 50%) proportion was set up. Our experimental plant was perennial ryegrass (Lolium perenne L.). After the harvest of ryegrass we measured the fresh and dry weight of harvested plants, the P-, K-, Mg-contents, and the pH of soils.
    The three composts had different effect on dry weight production and on nutrient-supply of soil. We established that one of the compost had significantly larger effect on the dry weight of ryegrass compared to the others. In this study we proved that favourable compost/soil proportion is different in the case of different composts.