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The impact of different fertilization methods on some microbiological soil characteristics
119-126Views:114In our experiment, we studied the impact of an organic fertilizer, Bactofil® A10 (half- and full dosage applied in field practice) and an artificial fertilizer of Ca(NO3)2 content in different dosages (20-40 mg kg-1) – in addition to control treatments – on two different soils (calcareous chernozem, humus sandy soil) in 2005-2006, the experiment was complemented with treatments applying 250% dosage (100 mg kg-1 N, Bactofil® A10 2.5 times the field dosage) and a compost from urban sewage (25 g kg-1 compost) was also tested on these two soil types. In the
experiment, several soil microbial parameters were studied. The experiment was set up at the Department of Agrochemistry and Soil Science using 1-kg pots.
Our laboratory experiments were performed at the soil microbiology laboratory of UD CAS Department of Agrochemistry and Soil Science, the total number of bacteria, microscopic fungi, nitrifying and aerob cellulose-decomposing bacteria were determined together with the CO2-production of soil, N content of the biomass and urease enzyme activity.
Statistical analysis of the data was done using the program SPSS 13.0, means of the measurements, deviation and significance values were calculated.
In 2005-2006, the effect of the different dosages of Bactofil® A10, and the Ca(NO3)2 fertilizer on the examined microbial parameters of calcareous chernozem and humus sandy soils can be summarized as follows:
• Concerning the total number of bacteria, both treatments were effective on calcareous chernozem soil, the higher (significant) increment in bacteria number was observed in the artificial fertilizer treatments, while in the humus sandy soil Bactofil treatments had a beneficial effect. The number of microscopic fungi also increased in both treatments, higher numbers were observed in the average of two years in the Bactofil treatments.
• The number of nitrifying bacteria was 2.5 times higher in both high-dosage treatments on calcareous chernozem soil, while on humus sandy soil a slight (not significant) increment was observed only int he high-dosage Bactofil treatment. The amount of aerob cellulose-decomposing bacteria significantly increased on calcareous chernozem soil in both the highdosage artificial fertilizer and the small-dosage Bactofil treatment, however, on humus sandy soil no significant increase was observed in either treatment.
• The CO2-production increased in both soil types, although it was not significant in either treatment. A higher (though not significant) soil respiration was observed in the Bactofil treatments in both soil types.
• The microbial biomass N values were significantly higher in the high-dosage Bactofil treatments, however, the high-dosage artificial fertilizer treatment also increased these values significantly on calcareous chernozem soil.
• On calcareous chernozem soil, urease activity was significantly increased and reduced by high-dosage artificial fertilizer treatments and Bactofil treatments, respectively. On humus sandy soil, urease activity was also reduced except for the high-dosage artificial fertilizer treatment. In 2007, the pot experiment with 250% dosages was complemented with the application of compost rich in organic matter, the results of these treatments are sumnmarized as follows:
• In the case of the total number of bacteria, all three treatments resulted in a significant increase on calcareous chernozem soil with the highest values in the Bactofil treatment. The Bactofil treatment was the most effective on the humus sandy soil, but the artificial fertilizer treatment also
resulted in a significant increment. In the case of the total number of fungi, Bactofil treatments resulted in the highest values on both soils, but the compost treatment also increased the number of fungi in calcareous chernozem significantly.
• The number of nitrifying bacteria was increased most (significantly) by the Bactofil and compost treatments on both soil types. The amount of cellulose-decomposing bacteria was significantly increased by he compost treatment on calcareous chernozem soil, while its effect was not significant on humus sandy soil. The number of these bacteria was increased significantly by the Bactofil treatment on humus sandy soil.
• On calcareous chernozem soil, all three treatments significantly increased CO2-production, while the compost treatments had the resulted in the largest increment in soil respiration on both soil types.
• The soil biomass N content was significantly increased in both soils by the compost treatment, while in the case of the humus sandy soil, the Bactofil treatment also resulted in a significant increment.
• Urease enzyme activity was significantly increased by the artificial fertilizer treatment on both soils. In calcareous chernozem soil, the Bactofil treatment resulted in a slight (not significant) reduction in enzyme activity. In humus sandy soil, the Bactoful treatment also resulted in a slight reduction, while the compost treatment increased (though not significantly) the urease activity.
Based on our results, it can be stated that all three treatments were effective with respect to the studied soil microbial parameters. For both the calcareous chernozem and the humus sandy soil, the organic fertilizer Bactofil and the compost with high organic matter content had a stronger effect on some soil microbial parameters than the artificial fertilizer. -
Assessment of Environmental Susceptibility/Vulnerability of Soils
62-74Views:100Soils represent a considerable part of the natural resources of Hungary. Consequently, rational land use and proper soil management – to guarantee normal soil functions – are important elements of sustainable (agricultural) development, having special importance both in the national economy and in environment protection.
The main soil functions in the biosphere are as follows: conditionally renewable natural resource; reactor, transformer and integrator of the combined influences of other natural resources (solar radiation, atmosphere, surface and subsurface waters, biological resources), place of „sphere-interactions”; medium for biomass production, primary food-source of the biosphere; storage of heat, water and plant nutrients; natural filter and detoxication system, which may prevent the deeper geological formations and the subsurface waters from various pollutants; high capacity buffer medium, which may prevent or moderate the unfavourable consequences of various environmental stresses; significant gene-reservoir, an important element of biodiversity.
Society utilizes these functions in different ways (rate, method, efficiency) throughout history, depending on the given natural conditions and socio-economic circumstances. In many cases the character of the particular functions was not properly taken into consideration during the utilization of soil resources, and the misguided management resulted in their over-exploitation, decreasing efficiency of one or more soil functions, and – over a certain limit – serious environmental deterioration.
Soil resources are threatened by the following environmental stresses:
– soil degradation processes;
– extreme moisture regime;
– nutrient stresses (deficiency or toxicity);
– environmental pollution.
Environmental stresses caused by natural factors or human activities represent an increasing ecological threat to the biosphere, as well as a socio-economic risk for sustainable development, including rational land use and soil management.
The stresses are caused by the integrated impacts of various soil properties, which are the results of soil processes (mass and energy regimes, abiotic and biotic transport and transformation and their interactions) under the combined influences of soil forming factors. Consequently, the control of soil processes is a great challenge and the main task of soil science and soil management in sustainable development.
The efficient control of these processes necessitates the following consecutive steps:
• registration of facts and consequences (information on land and soil characteristics, land use, cropping pattern, applied agrotechnics, yields, with their spatial and temporal variability);
• evaluation of potential reasons (definition and quantification of soil processes, analysis of influencing factors and their mechanisms);
• assessment of the theoretical, real, rational and economic possibilities for the control of soil processes (including their risk-assessment and impact analysis);
• elaboration of efficient technologies for the „best” control alternatives (best management practice).
Scientifically based planning and implementation of sustainable land use and rational soil management to ensure desirable soil functions, without any undesirable environmental side-effects, require adequate soil information. In the last years such data were organized into a computer-based GIS soil database in Hungary, giving opportunities for the quantification, analysis, modelling and forecasting of the studied environmental stresses and for the efficient and scientifically based prevention, elimination or reduction of environmental stresses and their unfavourable ecological and economical consequences.
Special attention was paid to the assessment of various soil degradation processes, as: (1) soil erosion by water or wind; (2) soil acidification; (3) salinization and/or alkalization; (4) physical degradation (structure destruction, compaction); (5) extreme moisture regime: drought sensitivity and waterlogging hazard; (6) biological degradation; (7) unfavourable changes in the plant nutrient regime; (8) decrease of natural buffering capacity, (9) soil (and water) pollution.
The actions against undesirable environmental stresses and their unfavourable consequences are important elements of sustainable, efficient, economically viable, socially acceptable and environmentally sound crop production and agricultural development. These are joint tasks of the state, decision makers on various levels, the land owners, the land users and – to a certain extent – of each member of the society. -
Statistical comparison of soil analysing results of chernozem soils
93-99Views:143The 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. -
Examination of CO2 emission of different stubbles on a chernozem soil
53-59Views:95Applying alternative soil cultivation methods based on reduced disturbance of the soil more favourable conditions can be created in order to increase the organic matter content of the soil and the availability of the nutrients for the crops. In complex soil tillage experiment – in 1997 was set on – at Karcag, as the element of the investigation of soil reduced and conventional tillage systems. There is close correlation between the degree and intensity of CO2-emission from the soil and the structural state and organic matter content of the soil. In order to quantify the increased CO2-emission from soil due to soil preserving cultivation systems, in situ CO2-emission of soil was measured by means of an ANAGAS 98 infrared gas analyser. The soil type of the investigated plot is meadow chernozem solonetz in the deeper layers, a soil type that is characteristic
for the Trans-Tisza Region of Hungary. In this paper the results gained from the measurement on different stubbles are published, as we consider stubbles the most suitable state when the effects of different soil cultivation systems on the microbiological activity of the soil can be compared. Experimental data provided information about the length of the time period when CO2 emission increasing effects of soil cultivation are observable. Studying the effect of different soil cultivation methods on the CO2 emission from chernozem soil is indisputably actual and needs more efforts as it can contribute to develop a more environmental friendly agricultural production. The main goal of these measurements was to determine the effect of soil cultivation technologies and certain agrotechnical elements on the factors of the soil carbon cycle. -
Comparative examination of a mineral fertiliser and a bacterial fertilizer on humic sandy soil
111-116Views:100In our pot experiment, the impact of a bacterial fertilizer, Bactofil® A10 and a mineral fertilizer Ca(NO3)2 applied in different rates was studied on some soil chemical and microbiological characteristics of a humic sandy soil (Pallag). Perennial rye-grass (Lolium perenne L.) was used as a test-plant. Samples were collected four and eight weeks after sowing in each year. The experiment was set up in 2007-2009 in the greenhouse of
the UD CASE Department of Agrochemistry and Soil Science. The available (AL-extractable) nutrient contents of soil, among the microbial parameters the total number of bacteria, the number of microscopic fungi, cellulose-decomposing and nitrifying bacteria, the sacharase and urease enzyme activity, as well as the soil respiration rate were measured.
Statistical analyses were made by means of the measurements deviation, LSD values at the P=0.05 level and correlation coefficients were calculated. Results of our experiment were summarised as follows:
− The readily available nutrient content of humic sandy soil increased as affected by the treatments, in case of the available (AL-extractable) phosphorus and potassium content the higher value was measured in high-dosage artificial fertilizer treatment.
− The treatments had also positive effect on several soil microbial parameters studied. The higher-dosage mineral fertilizer treatments had a beneficial effect on the total number of bacteria, cellulose-decomposing and nitrifying bacteria. No significant differences were obtained between the effect of treatment in case of the total-number of bacteria, the number of microscopic fungi and nitrifying bacteria.
− On the sacharase enzyme activity the artificial fertiliser treatments proved to be unambiguously stimulating, the urease activity significantly increased on the effect of the lower-dosage Ca(NO3)2 artificial fertilizer treatment.
− The soil respiration increased in all treatments in related to the amounts applied, significantly increased in the highest rate of Ca(NO3)2 fertilizer addition.
− Some medium and tight positive correlations were observed between the soil chemical and microbiological parameters studied in case of both nutrient sources.
Summarizing our results, it was established that the organic and all the mineral fertilizer treatments had beneficial effects on the major soil characteristics from the aspect of nutrient supply. In majority of the examined soil parameters (AL-extractable phosphorus- and potassium, total number of bacteria, number of cellulose-decomposing and nitrifying bacteria, activity of sacharase enzyme) the high rate of Ca(NO3)2 mineral fertilizer treatment proved to be more stimulating, but at the same time the high rate bacterium fertilizer resulted in significant increases in
the nitrate-N content, the AL-potassium content of soil, the total number of bacteria, the number of cellulose-decomposing and nitrifying bacteria and the urease enyme activity.
Our examinations showed that the mineral fertilizer treatments proved to be more stimulating on most of the soil parameters studied but according to our results, it was established that Bactofil is efficiently applicable in the maintenance of soil fertility and the combined application of
mineral fertilizer and bacterium fertilizer may be a favourable opportunity – also in aspect of the environmental protection – in maintaining soil fertility. -
New challenges in soil management
91-92Views:227Soil management represents two important tasks that are harmonization of the soil protection with demands of the crop to be grown on the given land under prevailing farming condition. Further goals are to preserve and/or develop the soil physical, biological and chemical condition and to avoid the unfavourable changes of the soil biological activity and the soil structure. Classical authors emphasised the importance of creating proper seedbed for plants. In the physical approach, tillage was believed to play an important role in controlling soil processes. Consequently, the period of several centuries dominated by this approach is referred to as the era of crop-oriented tillage (Birkás et al., 2017). The overestimation of the importance of crop requirements resulted in damaging the soils, which inevitably led to turn to the soil-focused tillage. Since the first years of climate change, as the new trends have raised concern, tillage must be turned into a climate-focused effort with the aim of reducing climate-induced stresses through improving soil quality.The development of soil management has always been determined by the economical background. At the same time, deteriorating site conditions have contributed to the conception of new tillage trends by forcing producers to find new solutions (e.g. dry farming theory in the past or adaptable tillage theory nowadays). Győrffy (2009) recited the most important keywords were listed in 2001 and that seemed to be important in the future of crop production. These keywords (endeavours) were as follows:− Biofarming, organic farming, alternative farming, biodynamic farming, low input sustainable agriculture;− Mid-tech farming, sustainable agriculture, soil conservation farming, no till farming, environmentally sound, environmentally friendly, diversity farming;− Crop production system, integrated pest management, integrated farming, high-tech farming;− Site specific production, site-specific technology, spatial variable technology, satellite farming;− Precision farming.Győrffy’s prognosis proved to be realistic and the efforts mentioned above have mostly been implemented. New challenges have also appeared in soil management in relation to the last decades. The most important endeavours for the future are:1) Preserving climate-induced stresses endangering soils.2) Turn to use climate mitigation soil tillage and crop production systems.3) Applying soil management methods are adaptable to the different soil moisture content (over dried or wet may be quite common).4) Use effectual water conservation tillage.5) Use soil condition specific tillage depth and method.6) Adapting the water and soil conservation methods in irrigation.7) Preserving and improving soil organic matter content by tillage and crop production systems.8) Considering that stubble residues are matter for soil protection, humus source and earthworm’ feed.9) Site-specific adoption of green manure and cover crops.10) Applying site-adopted (precision) fertilization and crop protection. Considering the development in agriculture, new endeavours will occur before long. -
Soil analysis as the foundation of precision nutritive supply in the Hajdúszoboszló region
141-148Views:94Larger 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. -
Comparative examination of a bacterium preparation (BACTOFIL® A10) and an artificial fertilizer [CA(NO3)2] on calcareous chernozem soil
75-80Views:134In a small-pot experiment a bacterium preparation, Bactofil® A10 and an artificial fertilizer containing Ca(NO3)2 in different dosages were studied on calcareous chernozem soil, concerning the readily available nutrient content of soil (nitrate-nitrogen, AL-phosphorus, ALpotassium content of soil, some soil microbial characteristics (total number of bacteria and fungi, cellulose-decomposing and nitrifying bacteria, CO2-production of soil), and the amount of the plant biomass.
The readily available nutrient content of the calcareous chernozem soil increased due to the treatments, except for the change in the soil nitrate-nitrogen content, which did not measure up to the control due to the effect of high-dosage Bactofil.
The treatments also influenced the examined microbial characteristics of the soil positively. The artificial treatments significantly increased the total number of bacteria and the number of cellulose-decomposing and nitrifying bacteria. The low-dosage Bactofil significantly increased the number of cellulose-decomposing bacteria and both Bactofil dosage significantly increased the number of nitrifying bacteria. The measure of the soil respiration grew in all treatments, but significantly only in Ca(NO3)2 fertiliser treatments.
The quantity of the plant biomass was grew in a low-dosage Bactofil and significantly in the artificial fertiliser treatments. The highest plant biomass quantity was measured in the high-dosage artificial fertiliser treatment.
In the correlation analyses we found some medium positive correlation between the soil chemical, microbiological parameters examined, and the plant biomass in the case of both treatment-forms.
Based on our results Ca(NO3)2 artificial fertiliser treatments on calcareous chernozem soil proved to be more stimulating regarding the
examined soil characteristics and the amount of the plant biomass, but the low-dosage Bactofil also positively influenced the majority of the
soil characteristics examined in terms of nutrient supply. -
Long-term effect of soil management on the carbon-dioxide emission of the soil
515-527Views:135CO2 emission from soils is one of the most important elements of the global carbon cycle, thus it has crucial rule in climate change. Each soil cultivation operation intervenes in the microbiological life of the soil, hence tillage is a factor through that the processes taking place in soil can be controlled. During the last decades, the organic material content of agricultural soils decreased to the half due to the intensive management resulting in the degradation of natural soil fertility. While intensive, plough-based tillage can cause soil degradation and erosion, the physical, chemical and biological status of the soil can be significantly improved through the application of conservation tillage methods. The results of long-term experiments prove that soil protective tillage enhances the enrichment of organic matter in the top layer of the soil. In order to reveal the role of tillage systems in CO2 emission from the soil, regular measurements were carried out in the plots with conventional and reduced tillage of the soil cultivation experiment of Research Institute of Karcag. Anagas CD 98 and Gas Alert Micro 5w infrared gas analysers were used to measure CO2-concentrations, and a specially developed method (consisting of a frame and a bowl) was applied to delimitate the measuring area. Most of the measurements were done on stubbles after harvest in order to exclude root respiration. The weather conditions of the examined 10 years were very changeable providing a good chance to compare them to each other. We found the tillage operations resulting in higher emission values in both tillage systems. On stubbles higher and more even emission was characteristic to reduced tillage due to the lower degree of soil disturbance and higher soil moisture content.
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Nitrogen Supplying Capacity of Brown Forest Soil under Different Cropping Practices and 0.01 M CaCl2 Soluble Organic Nitrogen
17-23Views:111The best known and most remarkable example of continuous production in Hungary is the Westsik’s crop rotation experiment, which was established in 1929, and is still in use to study the effects of organic manure treatment, to develop models, and predict the likely effects of different cropping systems on soil properties and crop yields. In this respect, Westsik’s crop rotation experiment provides data of immediate value to farmers concerning the applications of green, straw and farmyard manure, as well as data sets for scientific research.
Although commonly ignored, the release of nitrogen by root and green manure crops has a significant impact on soil organic matter turnover. The design of sustainable nitrogen management strategies requires a better understanding of the processes influencing nitrogen supplying capacity, as the effects of soil organic matter on soil productivity and crop yield are still very uncertain and require further research. In the treatments of Westsik’s crop rotation experiment, nutrients removed from soil through plant growth and harvesting are replaced either by fertilisers and/or organic manure. Data can be used to study the nitrogen supplying capacity of soil under different cropping systems and its effect on the 0.01 M CaCl2 soluble organic nitrogen content of soil.
The aim of this paper is to present data on the nitrogen supplying capacity of brown forest soil from Westsik’s crop rotation experiment and to study its correlation with hundredth molar calcium-chloride soluble organic nitrogen. The main objective is to determine the effects of root and green manure crops on the nitrogen supplying capacity of soil under different cropping systems. The nitrogen supplying capacity was calculated as a difference of plant uptake, organic manure and fertiliser supply.
The 0.01 M CaCl2 soluble organic nitrogen test has proved reliable for determining the nitrogen supplying capacity of soils. Brown forest soils are low in organic matter and in the F-1 fallow-rye-potato rotation, the nitrogen supplying capacity was 15.6 kg/ha/year. 0.01 M CaCl2 soluble organic nitrogen content was as low as 1.73 mg/kg soil. Roots and green manure increased the nitrogen supplying capacity of soil by more than 100%. This increase is caused by lupine, a legumes crop, which is very well adapted to the acidic soil conditions of the Nyírség region, and cultivated as a green or root manure crop to increase soil fertility. -
Changes of some soil chemical and microbiological characteristics in a long-term fertilization experiment in Hungary
253-265Views:329Agricultural management practices – directly or indirectly – influence soil properties.
Fertilization rates and crop rotation can strongly affect soil pH, soil nutrient supply and soil organic matter content due to the changes of microbial processes. The objective of this study was to compare the effects of different fertilization doses in monoculture and tri-culture of maize (monoculture: only maize grown since 1983, tri-culture: it is a three-year crop rotation system: pea – winter wheat – maize) on selected soil characteristics. The long-term fertilization experiments were set up in 1983 in Eastern Hungary. These experiments are situated west of Debrecen in Hajdúság loess region, on calcareous chernozem (according to WRB: Chernozems).
The test plant was maize (Zea mays L.). One-one pilot blocks were selected from monoculture and tri-culture of the long-term experiments. The observed soil samples were taken in the 30th year of the experiment, in 2013. The doses of NPK fertilizers increased parallel together, so the effects of N-, P- and K-fertilizers cannot be separated.
With the increasing fertilizer doses, the soil pH has decreased in both crop production systems and, in parallel, the hydrolytic acidity has significantly increased. A close negative correlation was proved between the pHH2O, pHKCl and hydrolytic acidity. An increased nutrient content in soil was recorded in every NPK treatment and the available phosphorus and nitrate content increased in higher proportion than that of potassium. Of the measured parameters of C-and N-cycles, fertilization has mostly had a positive effect on the microbial activity of soils. Besides the effects of fertilizer doses, correlation were looked for between soil microbiological properties. Evaluating the ratios among the measured parameters (organic carbon and microbial biomass carbon, OC/MBC ratio; carbon-dioxide and microbial biomass carbon; CO2/MBC proportion), the fertilization rate seems to be favoured by the increase of amounts of organic compounds
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Heavy Metals in Agricultural Soils
85-89Views:82The soil constitutes the basis of the food chain. To keep soil conditions in a good trim is very important, it’s part of the sustainable development and of producing food supply harmless to health.
In some cases, soil productivity is the only important part, qualitative requirements or economical characteristics can improve it. The soil is threatened by two danger factors: the soil degradation and the soil pollution. The accumulation of different harmful and/or toxic substances in the soil is well known. Heavy metals constitute a part of it. Metals in the soil and in the soil-solution are balanced. This balance depends on the type of the metal, on the pH, on the cation-band capacity of the soil, on the redox relations and the concentration of cations in the soil.
To be able to handle the metal contamination of the soil, it is important to estimate the form, the possible extension and the concentration of metals.
Of course, the different types of soils have different physical-chemical, biological and buffer capacity, they can moderate or reinforce the harmful effects of heavy metals. To draw general conclusion of the dispersion and quantitative relations on the metals originated from different contamination sources is hard, because in some emissive sources contamination is limited in small areas but on a high level, some others usually expand on larger areas, and as a result of equal dispersion, the contamination’s level is lower.
Heavy metals – unlike alkali ions – strongly bond to organic materials, or infiltrate in a kelát form. Their outstanding characteristic is the tendency to create metal-complex forms. Kelats take part in the uptaking and transportation of heavy metals. Heavy metals exert their effects mostly as enzyme-activators.
The metals cannot degrade in an organic way, they accumulate in living organisms, and they can form toxic compounds through biochemical reactions.
Lot of the heavy metals accumulate on the boundaries of the abiotic systems (air/soil, water/sediment), when physical or chemical parameters change, and this influences their remobilization.
Human activity plays a great part in heavy metal mobilization, results in the human origin of most biochemical process of metals.
To understand the toxic influence of accumulated metals of high concentration, their transportation from soils to plants or their damage in human health, must clearly defined and investigated.
For effective protection against soil pollution, the types and levels of harmful pollution to soil must identified, regarding legal, technical and soil-science aspects, preferable in a single way. Difficulties in this area mean that toxicity depends on loading, uptake, soil characteristics and living organisms (species, age, condition etc.), furthermore, local and economic conditions considerably differ. -
Mitigation of the effect of secondary salinization by micro soil conditioning
115-119Views:225This research has the general goal to meet the customization of agriculture in small scale farming. We are developing a technique using micro doses of soil conditioners and organic material applied in the root zone of vegetable crops. We expected to change the physical and chemical properties of the affected soil, which has been irrigated with salty water. Two different soil conditioners were tested. A lysimeter experiment including 8 simple drainage lysimeters was set up in the Research Institute of Karcag IAREF University of Debrecen in 2017. The main goal was to study the effect of different soil conditioners on the soil endangered by secondary salinization induced by irrigation with saline water. In order to compare the difference between the treatments, we collected soil samples, water samples, and determined the yields. Chili pepper (Capsicum annuum) was used as an indicator crop during one specific agricultural season. The technique called micro soil conditioning is rational because several reasons. The roles of the technique are various, for example it can serve as a source of carbon or a container for soil amendments and can minimize evaporation. We found this technique not to interfere with the chemical reaction or the interaction with the plants. However, the micro doses of soil amendments had the role to minimize the risk of soil degradation and do not significantly influence soil respiration. In addition, by improving soil properties, soil conditioning increases the leaching of the excess of salts from the root zone. In fact, this technique can decrease the cost of the inputs and improves the production of vegetables, and at the same time mitigates the effect of secondary salinization.
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The effect of bentonite on the quantity change of soil microorganisms, the CO2-production and the activity of saccharase enzyme
287-293Views:96We 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. -
Effect of Soil Covering on the Soil Enzyme Activity of Integrated Orchard
20-29Views:95The purpose of our experiments is to discover the effect of different soil cover matters (agrofoil and black polyethylene) on the activity of some enzymes (phosphatase, saccharase, urease, catalase, dehydrogenase) occuring in soil. Soil samples were taken from a cider apple plantation of the Fruit Producing Research and Advisory Kht Újfehértó. The enzyme activity was measured according to Krámer and Erdei (1959a), Kuprevič and Tsherbakova (1956), Kuprevič et al. (1966), Frankenberger and Johanson (1983), Mersi and Schinner (1991). Soil moisture content was by conventional (drying chamber) method measured during every sampling and enzyme activity was transpolated to absolute dry soil. Results were estimated by mathematical methods (variation analysis, correlation counting). Soil samples were taken by trials 5 times (in every two months) a year in the vegetation period from March to November.
By recording the monthly changes of the enzyme activity we have observed the following. The activity of the phosphatase was generally the highest in May and the lowest in November. Depending on the trials, high values were also measured in March and September. The activity of the saccharase was generally the highest in November and the lowest in June, but at the same time peaks even occured in May and September. The highest urease avtivity was measured in September and November, and the lowest activity in May and July, also depending on the trials. In the year 2000, after a deep point in March, the activity of the catalase was the highest in November or by certain trials in September. In 2001, the lowest activity was also measured in March, but the highest activity appeared in November in case of one-minute trial, and in May in consequence of two-minute trial. Finally the activity of dehydrogenase was the highest in November and the lowest in July apart from the model years.
There were essential differences in rainfall of the two experimental years which was reflected in the enzyme activities. There was a poor positive significant relationship between soil moisture content and enzyme activity values in case of phosphatase, saccharase, urease (r=0,426; 0,480; 0,396) respectively. In case of catalase1 (r=0,518), catalase (r=0,556), dehydrogenase (r=0,559) we obtained a medium strong positive relationship between soil moisture content and enzyme activity values. By evaluating the effect of different trials in case of every examined enzyme significantly higher values were detected in soils covered by agrofoil (a porous black polyethylene) than in soils covered by black polyethylene or in uncovered soils. Moreover, the soil covered by black polyethylene showed significantly higher enzyme activities (besides phosphatase) than the control soil. Thus soil-covering meant statistically significant advantages in enzyme activity as opposed to uncovered soil proved. -
Impact of the integration of lupine (Lupinus albus) into crop rotation on the extent of soil compaction in the Westsik longterm field trial
529-537Views:121In order to reduce or eliminate soil compaction, rational crop rotation and appropriate sequence of crops have an increasingly important role in addition to mechanical and tillage solutions. In this respect, introduction of greening in recent years has been a major step, which focuses on aspects of environmentally conscious, soil conserving farming and the improvement of biodiversity. The cornerstone of this strategy is the cultivation of crops that have a beneficial effect on soil properties, such as the use of nitrogen-fixing plants and green manure plants in the cultivation system that have a beneficial effect on soil structure. In our examinations, penetrometer measurements were carried out in the second longest crop rotation-based field experiment in Europe in order to quantify the effects of green crops and crop rotation strategies on soil resistance. Our aim was to evaluate and compare the impact of lupine (Lupinus albus) on the penetration resistance of soil on sour sandy soils. At the time of the penetration resistance measurement, different crop rotations had a significant effect on the development of the parameter in the examined soil layer. The most favourable penetration resistance values were found in the crop rotation, which included lupine as a green manure. The favourable effect is dominant below the cultivated layer (0–40 cm), which is statistically verified. The values of penetration resistance of the cultivated soil layer of lupine sown as primary green manure did not differ significantly from the values measured in the case of the fallowing-based crop rotation. Therefore, the use of lupine green manure instead of fallowing could be worth considering by practical application due to its favourable effects on soil penetration resistance. The use of lupine green manure after the production of rye cultivation resulted in penetration parameters similar to fallowing, irrespective of the green crop and the applied amount of nitrogen fertilizer, which justifies the cultivation of the crop as green manure. In the case of potato cultivating, recorded compaction within the cultivated layer is an obvious consequence of mechanical compaction during harvest; therefore, machinery operations are decisive for the development of penetration resistance values of the cultivated layer. In addition to the beneficial effect of lupine as a green manure crop on soil condition, its nitrogen-fixing ability is also important; it stresses the utilisation of the crop of sour sandy soils for the sake of proper soil management.
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The Effect of Soil Coverings on Soil Respiration in Sandy Soil
21-25Views:136The purpose of our experiments is to study effect of different soil coverings (porous black polyethylene called agroszövet and black polyethylene) on CO2 production in sandy soil. The CO2 production was measured in our laboratory according to Witkamp (1966 cit. Szegi, 1979), after 5 days’ incubation period. Samples were taken off four times (March, May, July, September) in every year of the experiment. In May, July and September of 2000, the CO2 production was significantly higher in the control than in the treatment soil. With the exception of September, the value of CO2 production was significantly higher under black polyethylene than under agroszövet. In March and May of 2001, the soil under black polyethylene, and in July and September the control soil produced the greatest quantity of CO2. With the exception of July, significantly more CO2 was produced under black polyethylene than under agroszövet. To study the dynamic of CO2 production there was find a significantly higher value May and September of 2001 than 2000. Similarly significant higher CO2 production was detected in September than in the other months In average of two experimental years the difference between the produced CO2 under different coverings was occasionally. Explicit upward tendency in soil CO2 production was detected only in case of control soil. There was a medium (r=0,413) relationship observed between the moisture content and the CO2 producing ability of soil. To sum up the soil coverings had favourable effect on soil CO2 production very rearly, but they could help to conserve the moisture content of soil.
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Nitrogen Content of Hungarian Soils and Nitrogen Fertilization
51-61Views:112For crop production and agricultural production, the most important natural resource is the soil that can optionally renew. Paralelly with this, soil plays a major role in the geological and biological cycle of elements. As a result of the big (geological) and small (biological) element cycles, the elements and combines neccessary for organisms can accumulate in the soil creating suitable living conditions for plants and other organisms. Soil is a heterogenous system both horizontally and vertically, and soil constituents show great variety in all the three dimensions, in addition, most of the parameters can also change between two examination dates. When talking about the factors influencing plant production, one should take into account this variation and heterogenity in time and space. When making fertilization recommendations, these factors should all be considered. In any consultation system, most of the mistakes and errors made are due to the unsatisfying soil testing and the negligence of soil heterogenity. In the practice of fertilization the biggest mistake is the improper soil sampling, then comes the methodical mistake of soil testing, which is followed by the inaccuracy of instrumental analysis and the subjectivity of result evaluation, but the latter two are negligible compared to the others. Under normal, i.e. production conditions, the quantity and distribution of nutrients in the soil are greatly dependent upon the applied technology, the amount and form of the applied natural and artificial fertilizers and the quality of fertilization.
Fertilization recommendations are needed because in the layer which is accessible for plant roots only a part of the nutrient content is available for plants in a specific production cycle. An illustration of this is that though the upper 1 m layer of an average chernozem soil contains more than 5000 kg N, 12000 kg K2O and 1500 kg P2O5 (form of expression mostly used in Hungary), the application of fertilizer doses which are just fractions of these quantities is essential. This is due to the fact that the available amount of the total nutrient content depends from the quality of soil, the environmental factors (the physical and chemical qualities of the soil) and the specific nutrient’s qualities (solubility, adsorption). Knowledge of these processes and the examination of the factors influencing the actual nutrient content are vital for working out a fertilization practice, which does not put more strain on the environment than neccessary.All of the above mentioned should be considered when applying inputs in the fields. In a well-functioning practice that considers the economic and environmental conditions (unfortunately the present production and economic conditions do not enable an appropriate level and degree), three nutrients are supplemented generally (and were supplemented in the last decades): nitrogen, phosphorus, potassium.
Studying the nutrient balance of the Hungarian field production’s last hundred years, we can draw some interesting conclusions.
The nutrient balance became positive for nitrogen and potassium in the second half of the 1960’s, while for phosphorus it was positive from the first half of the 1960’s and this period lasted until the end of the 1980’s.
Neither before the 1960’s, nor since the 1990’s has the amount of nutrients supplemented in a specific year reached the amount of the nutrient uptake of the same year. -
The application of bentonite and zeolite for soil amelioration in acidic sandy soil
131-137Views:119In 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 of the physical state of the soil under conventional and reduced tillage systems
183-186Views:166he effect of reduced and conventional tillage systems on soil compaction and moisture content in two years with extreme weather conditions is introduced in this paper. The investigations were carried out in a long-term soil cultivation experiment set on a heavy textured meadow chernozem soil at the Karcag Research Institute. In 2010 the amount of precipitation during the vegetation period of winter wheat was 623.3 mm, 2.2 times higher than the 50-year average, while in 2011 this value was 188.7 mm giving only 65% of the average. The examinations were made after harvest on stubbles on 4 test plots in 5 replications in the case of each tillage system. Soil compaction was characterised by penetration resistance values, while the actual soil moisture contents were determined by gravimetry. The values of penetration resistance and soil moisture content of the cultivated soil layer were better in the case of reduced tillage under extreme precipitation conditions. It could be established that regular application of deep soil loosening is essential due to the formation of the unfavourable compact soil layer under 30 cm. Conventional tillage resulted in enhanced compaction under the depth of ploughing, the penetration resistance can reach the value of 4 MPa under wet, while even 8 MPa under dry soil status.
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Effect of PRPSOL soil conditioner on the physical status of the soil in conventional and reduced tillage systems
109-113Views:229The effect of PRP-SOL soil conditional on soil compaction, moisture content and bulk density is studied in a long-term soil cultivation experiment from 1997 on a heavy textured meadow chernozem soil, in reduced and conventional tillage at Karcag Research Institute. Our investigations were made in the vegetation period of corn, in June and after harvesting, on stubble. Soil compaction was measured with a penetrometer, the actual moisture content was determined by gravimetric method. The bulk density values of the regularly cultivated soil layer of 0–10 and 10–20 cm depths were defined from undisturbed soil samples. We established that after 3 years the application of the soil conditioner has positive effect on soil compaction and moisture status of the top layer in the reduced tillage system. We could not figure out this positive effect in the case of conventional tillage.
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Comparative analysis of soil analysing datas on different sempling-plots
85-90Views:86Hibrid 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. -
Effects of water deficit on the growth and yield formation of maize (Zea mays L.)
143-148Views:171Maize (Zea mays L.) is the most important consuming cereal crop in the world after rice and wheat. This requires an understanding of various management practices as well as conditions that affect maize crop performance. Water deficit stress during crop production is one of the most serious threats to crop production in most parts of the world and drought stress or water deficit is an inevitable and recurring feature of global agriculture and it is against this background that field study of crops response to water deficit is very important to crop producer and researchers to maximize yield and improve crop production in this era of unpredicted climatic changes the world over.
A pot experiment was carried out to determine the effects of water deficit on growth and yield formation of maize. Two maize cultivars were used Xundan20 and Zhongdan5485. Three levels of soil water content were used in two stages of water control levels at two stages of the maize plant development
1. The JOINTING STAGE: A. CONTROL (CK) soil water content: from 70% to 80% of soil water holding capacity at the field, soil water content: from 55% to 65% of soil water holding capacity at the field, soil water content: from 40% to 50% of the Soil water holding capacity at the field.
2. The BIG FLARE PERIOD: A. CONTROL (CK) soil water content: from 75% to 85% of soil water holding capacity at the field, soil water content: from 58% to 68% of soil water holding capacity at the field, soil water content: from 45% to 55% of the soil water holding capacity at the field.
This research mainly studied the effects of water deficit on physiological, morphology and the agronomical characteristics of the maize plant at the different water stress levels.
The importance of these results in this experiment will enable plant producers to focus and have a fair idea as to which stage of the maize plant’s development that much attention must be given to in terms of water supply. -
The effect of different microbial preparations on some soil characteristics
83-86Views:113In pot experiment the effect of different microbial inoculants and their combinations with NPK fertilizer and wheat straw on some soil properties (physical, chemical, and microbiological parameters) were studied. The experiment was set up in 2011 at the Institute of Agricultural Chemistry and Soil Science, in a three replications, in a random block design. The studied soil type was calcareous chernozem soil from Debrecen (Látókép) with ryegrass (Lolium perenne, L.) test plant.
At the end of the experiment in our laboratory the nitrate-nitrogen content of soil, the AL-soluble phosphorus and potassium content of soil, the urease enzyme activity of soil, the total number of bacteria and the number of microscopical fungi were determined.
The results of the study were the following:
– The straw treatment and the straw + biofertilizer combinations influenced positively the nitrate content of soil.
– The NPK fertilization and the straw+bacterial fertilizer combinations had significant positive effect on the AL-soluble phosphorus content of the soil.
– The biofertilization and the straw+biofertilizer combinations stimulated the AL-soluble potassium content of soil occasionally.
– The total number of bacteria was influenced by the NPK fertilization, the bacterial fertilization and the straw+bacterial fertilizer combinations significantly.
– In case of the number of microscopic fungi caused in some cases significant changes the NPK+bacterial fertilizer and straw+bacterial fertilizer combinations.
– The soil urease enzyme activity was increased in all cases strongly especially by the straw+bacterial preparation combinations. -
The effect of nickel-contamination, nitrogen-supply and liming on the chemical composition of perennial ryegrass (Lolium perenne L.)
85-92Views:107Plant-production is determined by many production-factors. Each of these factors became subject of research-works through the years, still we state, that studying their interaction is even more important. For studying these interactions we set up a potexperiment, within that the direct effect and the interactions of four factors was inspected: soil, nitrogen-supply, nickel-loading and liming. Experiments were carried out on two soil types with extremely different characters: one was a chernozem soil with good fertility and buffering capacity, the other was a shifting sand soil with low humus-content and buffering capacity. Nitrogensupply and liming was added on two levels, while nickel on three within 12 combinations on each soil types. Plant production was cut two times within the vegetation period. The amount of production and dry matter was weighted, fractured and their element-content was measured by an ICP-detector.
Ca-content on the shifting sand soil was determined by all three factors, however the interaction between nickel-loading and liming was also significant. Nitrogen and liming increased Cauptake, that is due to appropriate nutrient-supply and improvement of a better pH-value. On the chernozem soil nitrogen and CaCO3 also increased the Ca-content. This is caused by a better nutrient supply and a higher amount of available Ca-ions.
On the shifting sand soil nickel content was increasing parallel to higher nitrogen-dosages. In presence of higher nickelamount the nickel-content of plants was also increasing, still according to liming, this increment was different. On the chernozem soil nitrogen a nickel increased Ni-uptake. However, liming also had a positive effect on Ni-content, that can be explained by the high amount on colloids in the soil, the adsorption of Ni-ions on them and in presence of liming material the replacement of Ca-and Ni-ions.
The potassium-content on the shifting sand soil was different in each liming-combination. In combinations without nickel the potassium-content of limed and not limed combinations was on the same level. In not limed combinations by adding nickel potassiumcontent was increasing, while in limed combinations no change was observed. On the chernozem soil by adding liming material the amount of uptaken potassium was decreasing, that is due to the antagonism between Ca- and K-ions.