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Evaluation of Soil Degradation Based on High Resolution Remote Sensing Data
145-148Views:76Soil salinity is the main problem of soil degradation in the Grate Plain with cultivated area of 20% affected. Its influence is accelerated on the water managed and irrigated lands. Remote sensing can significantly contribute to detecting temporal changes of salt-related surface features. We have chosen a farm where intensive crop cultivation takes place as a test site as soil degradation can be intensive as a result of land use and irrigation. In order to evaluate soil salt content and biomass analysis, we gathered detailed data from an 100x250 m area. We analyzed the salinity property of the samples. In our research we used a TETRACAM ADC multispectral camera to take high resolution images (0,2-0,5 m) of low altitude (300-500 m). A Normalized Vegetation Index was computed from near infrared (750-950 nm) and red (620-750 nm) bands. This data was compared with the samples of investigated area. Analyzing the images, we evaluated image reliability, and the connection between the bands and the soil properties (pH, salt content). A strong correlation observed between NDVI and soil salinity (EC) makes the multispectral images suitable for construction of salinity map. A further strong correlation was determined between NDVI and yield.
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Change of soil nitrogen content in a long term fertilization experiment
39-44Views:136The most important aim of sustainable agriculture is to ensure our natural resources – such as soils – protection, which includes fertility preservation and the use of appropriate methods of cultivation.
If we want to get accurate information about the occurred changes, way and danger of changes, we should track the resupply and effect of the mineral nutrients and the removed quantity of nutrients with the harvest.
Nitrogen is an essential element for living organisms and it is present in the soil mainly in organic form. In general only a low percentage of the total nitrogen content can be used directly by plants in the soil. The mineral nitrogen is incorporate by plants into our bodies. This inorganic nitrogen is produced by the transformation of organic contents through mineralization processes and it gets into the soil by fertilization. This is how nitrogen turnover occurs when mineral forms become organic and organic forms become mineral.
The objective of this publication was to introduce – through some element s of nitrogen turnover- how changing the properties of soil in a long term fertilization experiment.
We established that the fertilization is influenced the soil pH. With the increase of fertilization levels increased the acidity of the soil, maybe it is related with the number of nitrification bacteria. The fertilization and the rotation affected to the quantity of nitrate.
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Investigation of soils of stubbles of winter wheat and winter peas in conventional and reduced tillage systems
95-99Views:187The effect of reduced and conventional tillage on soil compaction, soil moisture status and carbon-dioxide emission of the soil was studied on a meadow chernozem soil with high clay content in the soil cultivation experiment started in 1997 at Karcag Research Institute. Our investigations were done on stubbles after the harvest of winter wheat and winter peas after the very droughty vegetation period of 2014/2015.
We established that the soil in both tillage systems was dry and compacted and the CO2-emission was very low. The positive effects of reduced tillage could be figured out only in the soil layer of 40–60 cm in the given weather conditions of that period.
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Soil Biological Activity within Integrated and Ecological Management of Soil
47-52Views:76The effects of the integrated (IS) and ecological (ES) management of soil on chosen parameters of soil biological activity were investigated in the period 1999-2000. The following characteristics were determined: biomass of microorganisms (Cmic), dehydrogenase activity (DHA), an amount of potentially mineralizable nitrogen (Nbiol), and nitrification intensity. Soil samples were collected from a stationary field experiment established in 1990 on gley brown soil at the Experimental Station of Slovak Agricultural University, Nitra. For each field with a different crop rotations two fertilization treatments were selected: (a) no fertilization and (b) use of manure for silage maize and, within IS, also mineral fertilizers. There was a statistically significant difference at α = 0.05 in the amount of biologically released nitrogen (Nbiol) between both systems and in the nitrification intensity in favour of ES. A higher amount of microbial biomass (Cmic) was noted for ES but without statistical significance. Cultivated crops and the timing of soil sampling were found to have the greatest effect on all the parameters observed in individual experimental years and within the two systems of soil management.
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Regulation in Hungary of the Use of Waste Water and Sewage Sludge in Agriculture
143-149Views:104Regulating the use of waste water and sewage sludge in agriculture in such a way as to prevent harmful effects on soil, vegetation, animals and man.
In European Union there is a Council Directive (86/278/EEC) on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture.
In the enlargement process of the European Union the Hungarian Government created a new rule (50/2001. (IV. 3.) Government regulation) which regulate using of waste water and sewage sludge in agriculture. This Hungarian rule is legal and reconcilable with the Council Directive.
The Regulation lays down limit values for concentrations of heavy metals in the soil, in waste water, in sludge and for the maximum annual quantities of heavy metals which may be introduced into the soil.
Waste water, sludge and soil on which it is used must be sampled and analysed.
Sewage sludge must be treated for six months before being used in agriculture.
The use of waste water and sludge prohibited on grassland, on nature reserved areas, in ecological farming, and soil in witch fruit and vegetable crops are growing, with the exception of fruit trees.
The states soil conservation authority must keep records registering the following:
– the quantities of waste water and sludge produced;
– the composition and properties of sludge;
– the type of treatment carried out;
– the names and addresses of the recipients of the sludge and places where the sludge is to be used.
The Government every four years must prepare a consolidated report on the use of sludge in agriculture, specifying quantities used, criteria followed and any difficulties encountered. This report must be forwarded to the Commission.
Last but not least in the light of Member States reports, the Commission will if necessary submit appropriate proposals for increased protection of the soil and the environment. -
Preliminary Critical P-limit Values of 0.01 M CaCl2 Soil Test Procedure
18-21Views:103In the last decade, the 0.01 M CaCl2 extraction procedure was tested as a multi-nutrient extractant. In 1995-97, international joint research activities were carried out within the COPERNICUS project. Detailed calibration of conventional and the 0.01 M CaCl2 extraction procedures for pH, Mg and K were published.
The amount of phosphorus extracted using a 0.01 M CaCl2 solution is very low and reflects the intensity parameter of phosphorus bio-availability. As a readily desorbed P fraction of soils can reflect the soil P-supply and the CaCl2-P values are in close correlation with P-fertiliser rates and P balance. However, the effects of various soil characteristics on CaCl2-P values are different and their interpretation is difficult.
Relatively poor correlations were found between amounts of P extracted by conventional and CaCl2 soil test methods and, therefore, P limit values could not be calculated directly. To characterise the soil P supply at different sites, the CaCl2 desorbed P and the adsorbed P in a modified Baker Soil Test were also applied.
Soil test results of Hungarian long-term fertiliser experiments and recommended CaCl2-P limit values, calculated on yield effects and soil characteristics, are discussed. -
CO2 emission of the soil on barley stubble
95-102Views:100In the last decades the physical and biological status of the soils in Hungary significantly decreased. The degree and intensity of CO2-production of the soil is in close correlation to its structural status and organic matter content. In a complex soil tillage experiment at Karcag in situ measurements have been carried out since 2002 in order to determine the CO2-emission of the soil. Carbon-dioxide emission of the soil in the cases of conventional tillage and reduced cultivation system was analysed in a long-term cultivation experiment. The measurements were carried out after the harvest of the barley, thus root respiration was excluded. For the spatial delimitation of the measuring area a newly developed frame+bowl set was used. Based on measurements, significant differences between cultivation systems can be recognized due to the soil structure changes and its effects
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Examination the effects of different herbicides on the soil microorganisms of a calcareous chernozem
121-126Views:74Pesticides play a key role in fighting weeds, pests and parasitic fungi. According to surveys, pests reduce the yield of agricultural crops by 35% worldwide. Pests, fungi and weeds account for 14%, 12% and 9% yield loss, respectively (Gáborjányi et al., 1995). Chemicals have contributed to increasing and maintaining the yields of crop production for decades. Today, agricultural production (in spite of many efforts) is unthinkable without the use of pesticides (herbicides, insecticides and fungicides). On the other hand, these chemicals contribute to the pollution of the atmosphere, surface and underground waters, and agricultural soils, especially if they are applied improperly.
The sustainable agricultural production pays attention to environment-friendly cultivation-technologies; but at the same time it makes an effort to produce good quality and economical products. The examination of the herbicides’ secondary effects, fits into this chain of idas namely, how the herbicides affect – stimulating or inhibiting – the soil microbiological processes, prevention of soil fertility.
In the course of the experimental work the effect of herbicides on soil biological properties were examined in different maize (Zea mays) cultures. We wanted wished to know that how the herbicides affect the quantity change of soil microorganisms, the life of different physiological groups of bacteria and the activity of microorganisms. A small pot experiment was set up in 2008 with the application of two herbicides - Acenit A 880 EC and Merlin 480 SC – in the breeding house of the Department. The moisture content and nutrient supply were at optimal level in the experiment.
On the basis of results the following can be stated:
1. It can be stated that the two herbicides and all their doses affected negatively the number of total soil bacteria, the
inhibiting effects were significant. The quantity of microscopical fungi increased by the effect of Merlin 480 SC and decreased in the treatments of Acenit A 880 EC.
2. The Acenit A 880 EC had stimulating effect on the nitrate mobilization. The CO2-production was stimulated by the basic doses of herbicides; the other treatments did not influence the CO2-production significantly.
3. The quantity of microbial biomass-carbon –except for only one treatment- decreased significantly by the effect of herbicides. Besides it, the quantity of microbial biomass-nitrogen increased significantly in the treatments of Acenit A 880 EC.
4. The biomass of test plant decreased in the treatments of herbicides, their quantities were smaller than in the control. In the pots treated by Merlin 480 SC, parallel with the increase of doses decreased the quantity of plant-biomass. -
Soil biological challenges in our age
193-196Views:116The paper deals with the soil biological research and its contribution to the changed cropping strategy and to the sustainable and environmentally friendly farming and management. The paper emphasizes the importance of biodiversity, as one of the most important ecological functions of soil. The organisms, populations and communities living in the soil play a key importance in the preservation of soil fertility. The most important research areas are presented dealing with in the last decades the national researchers and the challenges we face regarding the current soil biological problems. We have to prepare to examine the soil biological effectiveness of the more widely spread bio-preparations, bacterium preparations, and bioregulators. The prerequisites are the versatile knowledge of the biological state of soils and monitoring examination of the different effects soils had (including the mentioned preparations).
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The effect of biopreparations in pot experiment
45-49Views:129In pot experiment the effect of Amykor and Organic Green Gold bioproducts and their combinations with NPK fertilizer on some soil properties (chemical parameters) and on the biomass of testplant were studied. The experiment was set up in 2012 at the Institute of Agricultural Chemistry and Soil Science, in a three replications, in a random block design. The studied soil typein the pot experiment was humus sandy soil from Debrecen-Pallag with onion (Allium cepa) test plant. At the end of the experiment (after 4 week) in our laboratory the samples of soil and plant were determined. The nitrate-nitrogen, AL-soluble phosphorus and potassium content of soil, the weight of green onion leaves, the wet weight of bulb and root of onion and biomass of onion. The results of the study were the following: – The treatments influenced positively the nitrate-nitrogen, the AL-soluble phosphorus and potassium content of soil. – The most effective treatments were the artificial fertilization (NO3-N) and the NPK+ simple dose of Amykor (AL-P2O5 and Al-K2O). – The NPK fertilization and the NPK+OGG (sprinkle in every 10 days) combinations had significant positive effect on the weight of green onion leaves. – The biofertilization and the straw+biofertilizer combinations stimulated the AL-soluble potassium content of soil occasionally. – The OGG treatment (sprinkle in every 10 days) had significant effective impact on the wet weight of bulb and root of onion. – The biomass of onion was increased by the artificial fertilization and OGG (sprinkle in every 10 days) treatment.
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The study of the fertilizing effect of wheat straw ash in a greenhouse experiment
47-51Views:172The effect of wheat straw ash as a fertlizizer was studied in a pot experiment with an acidic sandy loam soil (pHKCl=4.9) with weak K and P supply. The test plant was ryegrass (Lolium perenne). The treatments were the following: 1. control untreated soil, 2. NPK fertilizer, 3. small dose of ash (1.4 g kg-1), 4 large dose of ash (2.8 g kg-1), 5. small dose ash completed with NP fertilizers. Soil parameters (pHH2O, pHKCl, ammoinum-lactate soluble P, K, 0.01 M CaCl2 soluble PO43--P, K, Mn, Cu, Zn ) and plant parameters (yield, P, K, Ca, Mg, Zn, Mn uptake) were investigated. Based on the analysis of the straw ash sample and the results of pot experiment it can be stated that the wheat straw ash is suitable for the fertilization of the studied soil. The small dose ash completed with NP resulted in the largest yield increment (43%). In order of the treatments the pHKCl changes to: 4.9, 4.8, 5.2, 5.8, 5.1. As the N : P2O5 : K2O ratio is 0 : 1: 3.5 in the wheat straw ash sample, to reach optimal yield ash should be completed with N and P.
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The zooecological remediation of technogen faulted soil in industrial region of Ukraine steppe zone
111-115Views:72In Ukraine’s Steppe zone the extraction of minerals is important. To eliminate the consequences of coal mining the agricultural recultivation of the disturbed soil is used. Thus toxic compounds for human beings and the majority of plants and soil biota representatives, which can be found mining rock, get into plants and invertebrates by trophy chains. When remediating soil, it is necessary to create tropic conditions in order to provide the life of soil biota. Earthworms (Lumbricidae) are the primary decomposers of the organic material. They are numerous in soil and facilitate the improvement of natural and artificially created soil. This paper studies the possible influence of different variants of substrates, which are used in re-cultivation, the leaf litter from leaves of different wood species, as well as different levels of humidity on the representatives of soil saprophages. Optimal variants of artificial mixed-soil providing the stable existence of animals have been shown, which are recommended for the implementation of rehabilitation measures.
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Microbiological preparations affecting the soil nutrient availability and growth of ryegrass in a pot experiment
49-53Views:136The effects of different bacterial fertilizers and their combinations with NPK fertilizer and wheat straw were investigated on some soil properties (chemical parameters) and on the biomass production of testplant. The applied quantities of the bacterial fertilizers were the double of the recommended dose. The experiment was set up in 2013 at the Institute of Agricultural Chemistry and Soil Science, in a three replications, in a random block design. Calcareous chernozem soil; originating from Debrecen (Látókép) was used with ryegrass (Lolium perenne L.) test plant. At the end of the experiment (after 8 week) the samples of soil and plants were determined for nitrate-nitrogen, ALsoluble phosphorus and potassium content of soil, the weight of green biomass of ryegrass per pot, the dry matter and moisture content of ryegrass. Straw treatment resulted better water and available nutrient content of soil in general. Inoculation however was not improving the biomass production over the fertilizer treatment. Interrelation with the recommended dose could be further studied.
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Evaluation some important microbiological parameters of the carbon cycle in chernozem soils profiles
33-39Views:154Some chemical and microbiological properties of the carbon cycle were investigated in three chernozem soil profiles. The soil profiles originated from a long term fertilization experiment (potato) of the University of Debrecen, Látókép, Kryvyi Rig Botanic Garden (grassland) and a large-scale farm (sunflower) of Ukraine. The results of the organic C-content, total number of bacteria, microscopical fungi, cellulose decomposing bacteria, CO2-production, microbial biomass carbon and saccharase and dehydrogenase activities were compared and evaluated with the help of correlation analyses. Close correlation was found between the organic carbon content and the number of microscopical fungi,, saccharase and dehydrogenase enzymes’ activities, as well as close correlation was found between the dehydrogenase activity and microbial biomass-C and saccharase activity.
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Effects of long-term K fertilization and liming on the extractable and exchangeable K contents of a Haplic Phaeosem soil
141-145Views:30Effects 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. -
Sight-specific development of the tools for the measurement of CO2-emission of the soil
53-58Views:80Soil is the main source and at the same time the potential sink of greenhouse gases (e.g. CO2, CH4). Measurements were carried out in the experimental sites (soil tillage experiments and an extensive pasture) of the Karcag Research Institute of University of Debrecen, Centre for Agricultural Sciences to determine the CO2-emission of the soil. The in situ CO2-emission of soil was measured by means of an ANAGAS 98 infrared gas analyser in plastic (PVC) chambers, but this previously applied method (cylinders) was not suitable for the soil surface covered with grass,
hence a new instrument was needed to be invented. In order to measure CO2-emission on a larger area without deep disturbance of the soil, a special metal frame was created with a matching bowl. The most problematic part was the spatial delimitation of the measurement area as the surface of the soil can be very various and proper isolation is a must. We consider the frame+bowl method we developed suitable for measuring CO2-emission of pastures as well as other crop-fields. -
Relationship between the change of soil moisture content of different soil layers and maize yield
19-25Views:150The development of chernozem soil water management and its relationship with maize yields was studied in a 30-years long-term field experiment with different crop-rotation systems (mono-, bi- and triculture), in three crop years with different natural precipitation: a drought (2007), a wet (2008) and a dry (2009 one. The relevant soil layer was divided to three sub-layers: (0–60 cm, 61–120 cm, 121–200 cm) in which the development of soil moisture content was investigated during the whole vegetation. From the results it can be stated that change of the water stock of the upper soil layer (0–60 cm) was the most intensive. Both the direct effect of natural precipitation and irrigation could be observed in the most obvious way in it. Yield result of maize and the highest water supply deficit values in the vegetation were compared in our work too. According to the results it was revealed that among the three studied crop rotation systems it was the monoculture, the success of production of which depends the most of water supply. The most favourable crop rotation system was the triculture from both the aspect of the yield of produced crops and the favourable soil properties too.
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Magnesium uptake dynamism of maize (Zea mays L.) on prairie soil
83-89Views:70Different influence factors on the magnesium (Mg) uptake in case of three maize hybrids with different long vegetation period have been investigated at the Experimental Station of the University of Debrecen, Centre of Agricultural Sciences and Engineering, at Debrecen-Látókép. The soil of the experiment is a calcareous chernozem, based on loess, with high fertility, that is characteristic for soils of the region Hajdúság.
Upon irrigation is the experiment divided to main plots, by different hybrids into sub-plots, while treatments of five nutrientsupply levels with fixed N:P2O5:K2O rate (beside control)mean sub-subplots. Soil samples were taken from the upper, cultivated soil layer 3 times during the year 2008. Their pH has been measures in a 0.01 M CaCl2-solution and their Mg-content from the same solution and from ammonium-lactate acetic acid (AL) extract. Plant samples were taken seven times in the vegetation period, of which we measured the Mg-content. Beside this, the during the
vegetation period by maize biomass extracted Mg-amount has been calculated using fresh and dry matter weights. The effects of irrigation, hybrids and nutrient-supply levels on the soil pH and on the AL- and CaCl2-extractable Mg-amount have been studied, as well. After that I tried to find a correlation between soil pH and the Mg-content of soil determined in different extractants, beside this between the by the two solutions extracted Mg-amount. -
Modern approaches to assessment of PAHs bioavailability in soil for environmental toxicology research
35-36Views:103The efficiency of TENAX beads sorption method enabling to separate the bioavailable fraction of PAHs in the soil has been estimated. Due to the method the PAHs effects on soil biota have been explored. Laboratory investigations have ascertained possibility of application of TENAX beads sorption for soil quality assessment.
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Energy crops on less favoured (alkaline) soil
115-118Views:99The reduction in fossil energy and row material sources induces growing demand for renewable resources. The growing demand for herbal raw materials has land use impacts as well. One way to reduce the conflict between the food and energy crops can be the utilization of less favored areas by growing energy crops. Among the potentially available areas for this purpose the salt affected soils (SAS) occupy a significant territories. SAS with structural B-horizon (meadow solonetz soils) represent the most wide spread group of SAS in Hungary. About half of these soils have been reclaimed and used as arable land and the remaining 50% are used as grassland. Sweet sorghum production for manufacturing of alcohol production was investigated in a long term amelioration and fertilization experiment on a salt affected soil (meadow solonetz). By means of regression analyzes the effect of sodium content of the soil and increasing mineral fertilizer doses were studied. According to the multiple regression analysis only the effect of nitrogen fertilizer was significant. On the solonetz type salt affected soil the effect of water soluble salt content of the soil was not significant, but there was a closer correlation between the ammonium-lactate sodium content and the yield of sweet sorghum. The maximum green mass was 45–50 t ha-1, in the case of low Na content and high level of nitrogen fertilization.
In order to quantify the potential yield of natural grass vegetation the relationship between the soil forming processes and the grass vegetation
was investigated. Beyond the different forms of Na-accumulation, the spatial pattern (mosaic-like characteristic) is also an inseparable feature of salt affected soils. The difference in the water regime, caused by the micro-relief is the main cause of variability. The run-on water keeps the deeper parts of the catena position wet longer. The wet situation causes more intensive leaching. In the low-laying parts of salt affected soils species preferring wet situations (mainly Alopecurus pratensis) are in majority. On the higher parts of the micro-relief species tolerating dry situations (mainly Festuca pseudovina) are dominant. The yearly grass production of low laying areas can be 4–7 t ha-1 but because of prolonged wet conditions the grass is not grazed and mowing can only be in old state. This old grass is not proper for feeding, but it may be suitable as energy plant. -
Effect of different sources and doses of sulphur on yield, nutrient content and uptake by spring wheat
109-115Views:126The objective of this study was to investigate the effect of two sulphur forms (sulphate and tiosulphate) in combination with three different N:S ratios on the yield of spring wheat and total N- and S-content and uptake by the aboveground biomass on chernozem and sandy soil. In the greenhouse experiment, the effects of two sulphur forms were compared: sulphate (SO42-) and thiosulphate (S2O32-). The sulphate was applied as potassium-sulphate (K2SO4) and thiosulphate as ammonium-thiosulphate ((NH4)2S2O3). Increasing doses of both sulphur forms (24, 60, 120 kg S ha-1) were used with the same nitrogen dose (120 kg N ha-1) which caused three different N:S ratios background (1:0.2, 1:0.5, 1:1). Nitrogen was supplied in the form of monoammonium-phosphate (MAP), ammonium-nitrate and ammonium-thiosulphate. Plant samples were taken in three different development stages of spring wheat based on the BBCH scale: at the stage of BBCH 30–32 (stem elongation), BBCH 65–69 (flowering) and BBCH 89 (ripening). The total nitrogen and total sulphur content of plant at different development stages and also wheat grain were measured by Elementar Vario EL type CNS analyser. The nutrient uptake by plant and grain was calculated from the yield of spring wheat and the N and S content of plant. The grain yield on chernozem soil ranged between 6.31 and 12.13 g/pot. All fertilised treatments significantly increased the grain yield compared to the control. The highest yield was obtained in the case of the application of 120 kg N ha-1 and 60 kg S ha-1in sulphate form. The grain yield on sandy soil varied from 2.53 to 6.62 g/pot. The fertilised treatments significantly enhanced the yield compared to the control. The highest yield was observed in the case of the application of 120 kg N ha-1 and 60 kg S ha-1 in thiosulphate form. On chernozem soil the increasing doses of sulphur (24, 60, 120 kg S ha-1) with the same N dose (120 kg N ha-1) increased the N-content of spring wheat at all development stages and in the grain. The treatments with different sulphur sources did not cause further changes in the N-content. On sandy soil in the most cases the N-content did not change significantly as a result of increasing sulphur doses. The treatments with sulphate form basically resulted higher nitrogen-content than treatments with thiosulphate form. The treatments with increasing sulphur doses resulted higher S-content on both of chernozem and sandy soil in the case of all development stage. Comparing the effect of the applied sulphur sources on the S-content it can be stated that at the stage of BBCH 30–31 and 65–69 the treatments with sulphate form resulted higher sulphur-content. At the stage of BBCH 89 there was no significant differences in S-content of grain as a result of different sulphur-sources.
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The effect of different herbicide on the number and activity of living microorganisms in soil
76-82Views:119Sustainable plant growth, considering the difficulties of weed elimination, cannot be effective without the application of herbicides. However, these chemicals have enormous ecological implications, including effects on the microbiological communities of soils. It is advisable to use herbicides that have minimal secondary effects on the environment and soil-living microorganisms. In contrast, herbicides with prolonged growth stimulating or inhibiting effects are not suitable, because both types have strong influences on the number and activity of bacteria, thus causing changes in the ecological equilibrium.
Preceding small plot experiments, laboratory tests were carried out to study the effect of herbicides used in maize cultures on the number of bacteria and growth of microscopic fungi.
Substances that were observed to have stronger influences were applied in small plot experiments set up in the experimental garden of the Department of Plant Protection of the University of Debrecen. We studied the effects of four herbicides (Acenit A88EC, Frontier 900 EC, Merlin SC and Wing EC) on the microbiological properties of the soil. These herbicides were used in different concentrations in maize culture, and we investigated the effects in different soil layers.
In the laboratory experiments, we determined the total number of bacteria and microscopic fungi and examined the growth of Aspergillus niger, Trichoderma sp. and Fusarium oxysporum on peptone-glucose agar containing herbicides.
During the small plot experiments, soil samples were collected 3 times a year from 2-20 cm depth. The total numbers of bacteria and microscopic fungi were determined by plate dilution method, while the method of most probable number (Pochon method) was used to determine the numbers of nitrifying bacteria and cellulose decomposing bacteria. To evaluate the microbiological activity of the soil samples we measured carbon-dioxide release (after 10 days incubation), nitrate production (after 14 days incubation) and the concentration of C and N in the biomass.
We can summarize our results as follows:
• In laboratory experiments, herbicides caused a decrease in the number of bacteria and inhibited the growth of microscopic fungi.
• Frontier 900 EC and Acenit A 880 EC had the strongest inhibiting effect on microorganisms.
• In small plot experiments, herbicide treatment decreased the total number of bacteria and microscopic fungi.
• Herbicides caused a significant increase in the number of nitrifying and cellulose decomposing bacteria.
• Different herbicides containing the same active compound had similar influences on soil microoorganisms.
• A significant increase was observed in the physiological processes of tolerant microorganisms surviving the effects of herbicides -
Evolution of some components of agroecosystems productivity from Vinga Plain in water stress situations
174-179Views:60The researches are inscribed on line of substantiation of durable agricultural system, having main objective the prominence of
quantitative and qualitative modifications made on agro-system level under the effect of no-tillage system for wheat, maize and soybeans.
The experimental field is placed on a cambium chernozem, with a medium content of clay, dominant in the Prodagro West Arad agrocentre
and representative for a large surface in the Banat-Crisana Plain.
The passing to no-till system change the structure of technological elements, through less soil works, so the impact on agro-system is
different comparing with conventional tillage, first less the intervention pressure on agro-system ant secondly appears new interactions, new
equilibriums and disequilibriums.
Considering the evolution of soil humidity, the observations made monthly (by taking soil samples and laboratory determinations) for
the three cultures showed that in the no-till system, there are more uniform values in the soil profile, and in the variants where the deep work
of soil was made it could be observed a low increase of the water volume in the soil. -
Optimized balance between crop productivity, restoration and maintenance of vital soil functions and soil carbon sequestration and storage – the SmartSOIL (FP7) project
213-215Views:93Soils provide the most indispensable function of supporting the production of food and feed for a growing human population. At the same time they provide a range of regulating and supporting functions related to climate change and removal of greenhouse gases. The majority of the soil functions are closely linked to the flows and stocks of soil organic carbon (SOC); low levels of both flows and stocks may seriously interfere with several of the essential soil functions and thus affect the ecosystem services that soils deliver. Soil degradation is considered a serious problem in Europe and a large part of the degradation is caused by intensive cultivation practices in agriculture. The aim of the SmartSOIL project is to link the results of different scientific fields through a holistic and multidisciplinary approach and as a result develop a decision making tool contributing to sustainable development.
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Morphological Features of Two Poa Species on Different Soil Types in Seminatural Grasslands
35-39Views:64The Poa pratensis L. and the Poa angustifolia L. are close relative species whose morphological features vary greatly. Our goal was to examine how the inividuals from different soil types of these species differ statistically from one another, whether the morphological features of the variant species differ significantly, and whether they keep their specific features in dissimilar habitats.
The quantitative features of the populations developing on distinct soil types wich are statistically separate provide for the different phenotype forming effect of the soil types as variant habitats. There is connection between the soil types and the measurement of the ramets on every soil types. The morphometric values of P. pratensis – that are bigger in all habitats – show that this species genetically widely adapted. Significantly different morphological features were found, but because of the high environmental dependence of the morphological features and of the significantly different characteristics which reveal several overlaps between the two species, these characteristics cannot be considered as reliable identification keys.