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  • The effect of bentonite on the quantity change of soil microorganisms, the CO2-production and the activity of saccharase enzyme
    287-293
    Views:
    93

    We examined the impact of bentonite – the perspective improving material of sandy soils – and treatments of livestock manure composted with bentonite on sandy soils, within the framework of a small-plot experiment.
    The adjustment of the experiment was made on the Experiment Site of the Nyíregyháza Research Centre of the University of Debrecen, Centre of Agricultural Sciences (UD CAS). We collected soil samples from parcels treated with increasing bentonite doses (5, 10, 15, 20 t/ha) on the one hand, and from the parcels treated with livestock manure composted with increasing doses of bentonite, on the other.
    We performed laboratory research in the soil microbiology laboratory of the Soil Science Faculty of UD CAS DAS, during which we determined the total number of bacteria, the quantity of microscopic fungi, the number of cellulose-decomposing bacteria, the CO2-production of the soil and the activity of saccharase enzyme.
    During the evaluation of the examinations, we made a statistical analysis using SPSS 9.0. We determined the average of measurements, the standard deviation of controls, the standard deviation, the significance value and we also performed a correlation analysis.
    Concerning the impacts of bentonite treatment and the treatment of livestock manure composted with bentonite on the examined microbiological features of sandy soil, we can summarize the following:
    • Our results prove that the microbiologic activity of the soil has increased owing to the impact of bentonite treatments regarding total number of bacteria and the quantity of microscopic fungi. ”Pure bentonite” treatments – although not significantly in every case – increased these values, but larger doses decreased them. The treatments of livestock manure composted with bentonite resulted in a larger increase regarding both parameters.
    • The number of cellulose-decomposing bacteria was increased by the low doses of both series, and was decreased by the higher doses. Higher bentonite doses decreased it in a higher – significant – degree than those of treatments of livestock manure composted with bentonite, whose low dose caused salient number of bacteria.
    • Regarding the carbon-dioxide formation, we have experienced an increase even in the case of low dose treatments (nevertheless, the increase did not prove to be significant), but – similarly to the quantitative changes in the number of cellulose-decomposing bacteria – the large doses of both series of treatment decreased the CO2-production of the soil.
    • Bentonite also increased the activity of saccharase enzyme significantly. We learned that”pure bentonite” treatments increased the activity of the enzyme to a higher degree than composted treatments. Moreover, it can be stated that the treatments of larger doses of both bentonite and livestock manure composted with bentonite have decreased the enzyme activity – not significantly, though.
    • Based on the correlation analysis, it can be stated that as an impact of the treatments, the microbiological activity of the soil has also increased with the increase of the number of soil microbes, as in both treatment series we have experienced a tight positive correlation (r=0.81-0.82) between the change of total number of bacteria and the CO2-production of soil. In both treatments, there was a medium correlation between the total number of fungi and soil respiration (r=0.63-0.63). Furthermore, it can be stated that the usage of organic manure had a positive effect on the activity of cellulose-decomposing bacteria, as in this treatment series there was a positive correlation (r=0.65) between this physiological group and CO2-production. Both treatments prosperously impacted the activity of saccharase enzyme, because there was a medium correlation (r=0.62-0.64) between the activity of the enzyme and soil respiration.

  • The application of bentonite and zeolite for soil amelioration in acidic sandy soil
    131-137
    Views:
    116

    In a pot experiment, we have studied the effect of bentonite and zeolite in different dosages [control; 5; 10; 15; 20 g kg-1] on acidic (pHH2O=5.65) humus sandy soil. The experiment was set up in 2007 and 2008 in the greenhouse of the UD CASE Department of Agrochemistry and Soil Science. As a test plant, perennial ryegrass (Lolium perenne L.) was used. 
    In laboratory examinations, pH(H2O), pH(KCl), hidrolytic acidity, nitrate-N content, readily available phosphorus and potassium content were determined. Among soil microbial parameters, the total number of bacteria, the cellulose-decomposing bacteria, the carbon-dioxide production, the microbial biomass-C content of soil, and the saccharase enzyme activity were measured. In the experiment the biomass of the test plant was determined.
    The effect of bentonite and zeolite in different dosages can be summarized as follows:
    − The pH increased under the effect of low dosages. With the increasing of the pH the hydrolytic acidity - at the bentonite treatments significantly – decreased. 
    − Regarding the readily available nutrient content of the soil, low and medium dosages proved to be effective. High dosages of bentonite treatments reduced the nitrate-N content, the readily available phosphorus, and potassium content of soil, by zeolite treatments the high dosages reduced the nitrate-N content of soil. 
    − Regarding the measured soil microbial parameters in both treatments low and medium dosages proved to be also effective, but the high dosages didn’t cause decreasing at the total number of bacteria, and by zeolite treatments the biomass-C content of soil.
    − Also the bentonite and zeolite treatments enlarged the biomass of the test plant. We experienced significant increasing by bentonite treatments by the effect of medium and high dosages, while in zeolite treatments only the high dosage caused significantly increasing in plant biomass. The largest dosages decrease the plant biomass. 
    − Under the statistical analysis we found many medium and tight correlation between the studied parameters. 

  • Examination and statistical evaluation of physico-chemical parameters of windrow composting
    33-38
    Views:
    248

     

    The treatment and utilization of plant and animal waste and by-products from agriculture is very diverse. Traditional environmental management practices for waste management have been retained through soil conservation and the applied of recycle degradable organic substances in soil. The management of by-products from agriculture (animal husbandry) is important because a closed loop can be created to utilize by-products (manure, feathers) from the production of the main product (eggs, meat, milk) and to form a raw material for a new product. It is important to treat the resulting by-products, especially deep-litter manure, as it has served as a basis for compost-treated manure to develop an organic-based, soil-conditioning product line. Poultry manure by itself is not suitable as a substrate for aerobic decomposition, so it has to be mixed with other substances (zeolite, bentonite, soil), because of its high nutrient capacity, it is an acidifying substance.

    The aim of this study was to compost the mixture of poultry manure and hen manure by the addition of zeolite and to monitor the composting process. It was also our aim to statistically determine the effect of the zeolite on parameters describing the composting process.

    The windrow composting experiments were set up in the composting area of the University of Debrecen, Institute of Water and Environmental Management. The composting experiment was 62 days long, during which the main parameters describing the composting process were continuously monitored: temperature (°C), moisture content (w/w%), electrical conductivity (mS/cm), organic matter content (w/w%), examination of nitrogen forms (w/w%). In this study, three factors were investigated: temperature, humidity, and pH. For statistical evaluation, R software and RStudio user interface were used. We developed a repeated measurement model, in which the fixed and random effects were determined for our parameters under study, and the resulting relationships were shown on interaction plots.

    Based on our results, the temperature of the prisms has become independent of the ambient temperature and the composting stages can be separated in both the control and the zeolite treated prisms. In the repeated measurement model, we proved that treatment, time and treatment: time interaction were significant at both temperature and pH.

  • Effects of fermented chicken manure products on the N mineralization rate of the soil using the incubation method
    199-204
    Views:
    194

    In our study, the effect of fermented and specially added poultry manure products (superabsorbent polymer (SAP), bentonite and Aegis as a mycorrhizal inoculum) were investigated in a short soil incubation experiment – at 60% water capacity level - on sandy soil. Soil samples were collected from two layers of the incubation pots after the second and fourth week to check the status of the tested products and the processes in the soil. The pH and the electric conductivity (EC) of the samples were measured using an electrochemical method, while the ammonium and nitrate content of the samples was determined with a photometric method. Soil pH and EC values slightly were decreased during the experiment. Our results pointed out that the increasing dose of SAP caused lower soil pH. The nitrate content of the soil did not change significantly during the experiment. It was found that the increasing SAP content in the products, due to its cross-linked structural property, protected the nitrate ions from leaching. Our results suggest that applied SAP does not bind the nutrient ions so tightly in its structure that it competes with the plant for uptake.