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  • Hybrid-specific nutrient and water use of maize on chernozem soil
    51-54
    Views:
    116

    The field research was set up on chernozem soil at the Látókép AGTC KIT research area of the University of Debrecen. The study focused on yield, water utilization, nutrient reaction and the amount of yield per kg fertilizer of corn hybrid NX 47279 in 2011 and 2012. Based on the yield results it can be concluded that the largest yield in 2011 was 15 963 kg ha-1 at level N120+PK, while in 2012, the maximum yield amounted to 14 972 kg ha-1 at level N90+PK. Surplus yield per kg fertilizer proved that in 2011 level N30+PK resulted in the highest surplus yield (42.3 kg kg-1) compared to the control treatment. In 2012, yield growth was 18.0 kg kg-1 compared to the control treatment. We measured at level N60+PK 17,5 kg kg-1 compared to at level N30+PK, at the N90+PK 17,7 kg kg-1 compared to at level N60+PK. level N30+PK kg kg-1, 17.5 kg kg-1 at level N60+PK and 17.7 kg kg-1 at level N90+PK compared to the control treatment.

    Results of the regression analysis showed that the amount of nitrogen fertilizer was 117 kg ha-1 in 2011 and 111 kg ha-1 in 2012 in order to reach maximum yield. Doses of fertilizers above the amounts previously mentioned resulted in yield decrease. Our results indicated that in the drought year of 2012 the hybrid used available water more efficiently than in 2011. The hybrid produced 59 kg ha-1 yield in 2012 and 51.9 kg ha-1 in 2011 at an optimum nutrition level.

  • The effect of dissolved oxygen on common carp (Cyprinus carpio) and basil (Ocimum basilicum) in the aquaponics system
    89-96
    Views:
    356

    Aquaponics is an integrated system that combines fish farming (aquaculture) and hydroponic plant production. The objective of this study was to examine how the level of dissolved oxygen with or without an air pump affects water quality, fish output and plant growth parameters for common carp (Cyprinus carpio) and basil (Ocimum basilicum).

    Ebb – and flood aquaponics systems (with automatic syphon) was used. Two treatments were set in this experiment, one of which was the aquaponics system without air pump (unit I), where water of the plant bed was pumped two directions, one falling back to the fish tank oxygenating the water the other was pumped to the hydroponics unit. The other system (unit II) was designed with an air pump.

    In the course of the study, water quality parameters, such as oxygen saturation, dissolved oxygen (DO), electrical conductivity (EC) and nitrite were significantly different (p<0.05). Total basil biomass was higher in unit II. (5367.41 g). The final biomass of common carp were
    2829.45 g ± 79.24 and 2980.6 g ± 64.13 g in unit I and unit II respectively. Weight gain (WG) and specific growth rate (SGR) showed no significant differences (p>0.05) between the treatments. 

  • The effect of water-stress on the mineral nutrition of fruit plantations
    187-192
    Views:
    104

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

  • The Effect of the Mineral Content of the Leg-Horn and the Age of Sheep on the Mechanical Parameters of the Horn
    42-45
    Views:
    77

    Species and individual animals with hard leg-horn have higher resistance against foot diseases. The reason for this is the fact, that bacteria can penetrate the hard leg-horn with more difficulty than the soft leg-horn, and in this way it is also more difficult for them to cause an illness. From among the mechanical parameters of the leg-horn the P = 0.1% negative linear correlation between the hardness and the water contents of the horn is significant. There is a positive linear correlation between the shock resistance and the water contents of the leg-horn. In the case of air-dry horn (with less than 8% water contents) there is a positive linear correlation between the Ca- and Zn contents as well as the Ca:P ratio and the hardness of the horn. The results suggest that the wider the Ca:P ratio of the horn, the harder the horn is, while the water content is the same. The leg-horn of the Hungarian Merino ewes have larger Ca contents and wider Ca:P ratio than juvenile animals have. This is why the juvenile animals with a softer leg-horn can be more susceptive to foot diseases than the older animals.

  • Environmental friendly irrigation of vegetables with high salt content water
    115-119
    Views:
    166

    Horticultural activities have been characteristic in the hobby gardens located in the northern and western areas around the town of Karcag for more than 300 years. During the droughty summer periods, characteristic to the region, the water demand of vegetables and fruit trees are covered by irrigation, for that the water is gained from drilled wells. These well waters contain high amount of dissolved salts contributing to the secondary salinization of the soil. Taking these facts into consideration an irrigation experiment was set at the lysimeter station of Karcag Research Institute. Our goal was to mitigate the risk of secondary salinization generated by irrigation with waters of high salt content and to survey the application possibilities of soil preserving irrigation.

  • Improved soil and tomato quality by some biofertilizer products
    93-105
    Views:
    263

    The use of microbial inoculums is a part of sustainable agricultural practices. Among various bioeffectors, the phosphorus-mobilizing bacteria are frequently used.

    The objective of this study is to investigate the effect of some industrial biofertilizer inoculums, of containing P-mobilizing bacteria on the quantity and some quality parameters of tomato fruits. Spore-forming industrial Bacillus amyloliquefaciens FZB42 (Rhizovital) as single inoculums and combinations with other Bacillus strains (Biorex) were applied on Solanum lycopersicon Mill. var. Mobil test plant. Soil microbial counts, phosphorus availability, yield and fruit quality, such as total soluble solids (TSS) content and sugars (glucose, fructose) were assessed. The results found that single industrial inoculums of FZB42 product had positive effect on P-availability and fruit quality in the pots. Fruit quality parameters, TSS content, soluble sugars were significantly improved (p<0.05). Such better fruit taste was correlated significantly by the most probable number (MPN) microbial counts. Use of such bioeffector products is supported by the positive interrelation among measured soil characteristics and inside healthy quality parameters of tomato fruits.

  • Evaluation of water balance in apple and pear trees
    193-198
    Views:
    125

    A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor
    of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates
    the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not
    an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree
    (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and
    fast evaluate the leaf surface. Furthermore we defined from the water balance of compensation lysimeters the cumulative transpiration of
    fruit trees and the efficiency of water use of trees.

  • Effect of Water and Nutrient Supply on the Allelopathy of Abutilon theophrasti Medic. and Xanthium italicum Mor
    102-105
    Views:
    74

    Velvetleaf (Abutilon theophrasti Medic.) and Cocklebur species (Xanthium spp.) are more and more dangerous and „difficult to control” weeds in several cultivated plants. The ground cover of these species have became larger in Hungary like other warm-philous species. There are several causes of danger of them, for example: large capability for competition, allelopathic effect, keeping on of emergence.
    The allelopathic effect of these weeds were examined on sugarbeet (Beta vulgaris L.). Extracts of plants grown under different conditions have several effect on this species.
    Abutilon theophrasti plants were grown in perlite to examine the effect of supplying with nutritive materials on production of inhibitors. The water soluble exudates of the shoots grown with no artificial fertilisers inhibit stronger than grown with them. Acid soluble exudates have contrary effect. The exudates made of roots inhibited the sugarbeet less than shoots.
    Effect of drought stress on production of inhibitors was examined on Abutilon theophrasti and on Xanthium italicum. The species responded to missing of water different, and the water, acid and basic soluble exudates had different effect, as well.

  • Examination and statistical evaluation of physico-chemical parameters of windrow composting
    33-38
    Views:
    244

     

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

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

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

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

  • Investigation of Salix alba and Populus tremula leaf litter decomposition in the area of Lake Balaton and Kis-Balaton Wetland
    159-162
    Views:
    166

    Plant litter decomposition in inland waters contributes significantly to nutrient load, particularly in still waters, such as shallow lakes and wetlands. The decomposition rates of Salix alba and Populus tremula leaf litter was examined in Lake Balaton and Kis-Balaton Wetland, using litter bag technique. Leaf litter was incubated in small (ᴓ=3 mm) and large (ᴓ=900 μm) mesh size bags for the assessment of the relative contribution of macroinvertebrates to leaf litter decomposition. Dry mass, exponential decay coefficient and chemical parameters of water (pH, conductivity, NH4 +, NO3 -, SO4 2-, PO4 3-, Cl-) were determined. Leaf mass loss showed negative exponential pattern during the 168 days of the decomposition period. Leaf litter mass loss generally did not differ between the small and large mesh sizes, suggesting that macroinvertebrates generally have a negligible role in leaf decomposition in the winter period.

  • Water managed properties of apple and pear trees based on lysimeters
    129-132
    Views:
    163

    A significant proportion of the aboveground green and dry weight of the plant is constituted by foliage. The canopy is an important factor of plant growth. On the one hand, the canopy absorbs solar energy, which is necessary for photosynthesis; on the other hand, it accumulates the nutrients absorbed by the roots, and most of the water-loss occurs through the foliage. The determination of the full canopy is not an easy target. In our research, we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of the ADC AM 100 leaf area scanner, we determined the k-value, with which we can easily and fast evaluate the leaf surface. Furthermore, we defined from the water balance of compensation lysimeters the cumulative transpiration of fruit trees and the efficiency of water use of trees. From the examined trees were made a 3D depiction, which show the shape, branching and the location of trees.

  • Changes in toxic elements content of soil after sewage sludge treatment in energy willow plantation
    7-10
    Views:
    121

    The primary purpose of our experiment was the solution of municipal excess sludge treatment by a renewable energy resource used willow (Salix viminalis L.) plantation. Tests were carried out to state whether the applied sewage sludge has caused any accumulation of the toxic elements in the studied soil layers, and - based on the results –to see whether the plantation is suitable for the treatment of municipal sewage sludge.
    The excess sludge (sludge before dewatering) is beneficial for the willow, because it contains a 3–5% dry matter and therefore, a lot of water, too. This high water content ensures the high water amount needed for the intensive growth of the willow. On the other hand, the wastewater treatment plant can save the dewatering cost which corresponds to about 30% of the water treatment process costs. The amounts of the sprinkled sewage sludge were calculated on the basis of its total nitrogen content. Treatments were the followings: control, 170 N kg ha-1 year-1 and 250 N kg ha-1 year-1. The mean values of the toxic element concentrations in the sewage sludge did not cross the permitted limits of the land  accommodating.

    The measured toxic element values of the soil were compared to the limits of the 50/2001. (IV.3.) Government Regulation.The  sprinkled sewage sludge on the bases of the total N content did not cause accumulation of heavy metals in the soil and the treated plants were also healthy without any signs of toxicity. 

  • Analysis of the Environmental Status of Nagykálló Subregion
    362-367
    Views:
    94

    The third smallest region of Szabolcs-Szatmár-Bereg county is the Nagykálló subregion. Its territory is 377 km2 and its inhabitants number 32.526. Due to the fact that industrial development arrived late, the environmental status of this subregion was saved from serious ecological degradation. The quality of the environment shows a reasonable picture in many respects, comparing to the general survey of the country. The air quality of the region can be qualified as acceptable. Leaving some critical points out of consideration, it is better than the national average. It is favourable from the human environment point of view that the region is free of extremes, and has a balanced climate. The supply of drinking water is above 95%, and the remainsing water requirements are supplied by artesian wells. The water supply network is fully extended in the subregion. The most significant environmental noise source is traffic, including public road traffic, which causes a problem in the town of Nagykálló. The situation of the collection, transportation, and placement of the settlement’s solid wastes show a similar picture to the status of the country. The environmental status of the region is included in the SWOT analysis.

  • Interactive evaluation of the main agrotechnical factors in rape production
    71-79
    Views:
    90

    Our polifactorial rape research was carried out at Látókép Research Centre of Debreceni Egyetem AMTC, 15 km away from Debrecen. The aim was to study the unique effect and the interactive effect of more factors. The research factors were the following: cultivation, time of sowing and nutrient supply. Soil moisture datas proved unambiguously that increasing amounts of chemical fertilizer raise the water consumption of rape, lack of water in fertilized plots were always bigger then the water deficit in control plots. The highest amount of water deficit was experienced in the case of arable plots. However, increasing amounts of chemical fertilizers raised the amount of yield proportionately. We experienced yield depression only in the case of arable plots at the highest level of chemical fertilization. In polifactorial rape research sowing of 24th August 2007 of 2007/2008 was the most optimal in point of the amount of yield. This is most-significant in the case of loosening tillage and disking tillage plots, while the plots of ploughing lag behind those two in point of average yield. We experienced the biggest differences of yield in the case of different tillage plots of sowing on 24t August 2007. Still not even the plot with the highest average reached the limit of 4 tons, which can be attributed to high rate of lodging and the harvest loss caused by this. The biggest amount of yield was experienced in the case of sowing of 24th August 2007, with the highest level of chemical fertilization at loosening tillage plot (3930 kg/ha). We can observe big differences between the tillage methods; plots of loosening show a much better average yield then plots of disking and ploughing tillage. Considering the first observed crop year we can state that alternative tillage methods do have a future in rape growing of Hungary. 

  • Clay-pit systems fishfaunistic research in the Middle-Tisza
    81-92
    Views:
    73

    After the regulation of the Tisza River the chance of successful fish propagation lessened. Natural spooning places in the river almost completely disappeared. The fish have to find an adequate place for their propagation in the flood plain. The period of spooning usually coincides with flooding of the river. At this time fish try to find the flooded shallow places for spooning. These parts mostly include the clay-pits beside dams, which were accidentally established during construction of the dams. At this place the fry can find the necessary food. After decreasing the flood the fingerlings and a part of the spooners are trapped inclay-pits as these latter ones are not connected with the river bed. The clay-pits usually desiccate during the summer. The trapped fish population is eaten by water birds or harvested by the local man population. This means a great loss for reproduction of some fishspecies.
    Within the framework of the Regional Rehabilitation Program at Nagykörű, supported by the “WWF Hungary” and a “SAPARD project,” these clay-pits became connected with each other in a stretch of 5 km, and they were jointed to the Tisza by a collecting channel. The water level has been regulated by a flood gate so that the water enters the holes during the flood and is released later on in to the water bed.
    Data on fish were collected from the Nagykörű Whole System, from the Anyita pond and some isolated wholes in Szandaszöllős in 2004 and 2005. First of all fish fry and fingerling were collected and the success of spooning at these places was examined. Fry was harvested by a 60 x 80 cm sized lifting net of 2x3 mm mesh size. In other cases nets used by anglers for catching prey fishes was also used. Data were also collected from local fishermen who participated in saving the fry and fishing of Anyita pond.
    Of the several thousand caught fish specimens 28 species were identified, and among them 5 protected and 5 economically important species was found. Protected fishes were as follow: gudgeon (Gobio gobio), bitterling (Rhodeus sericeus amarus), weather fish (Misgurnus fossilis), spined loach (Cobitis elongatoides) and tubenosed goby (Proterorhinus marmoratus). Among economically important fishessamples of asp (Aspius aspius), carp (Cyprinus carpio), wels (Silurus glanis), pike (Esox lucius) and pikeperch (Sander lucioperca) were

  • Examination of drought stress of two genotype maize hybrids with different fertilization
    53-57
    Views:
    119

    In the growing season of 2019, we analysed stress resulting from climatic factors on maize hybrids of different genotypes, with the aim of gaining a better understanding of the physiological responses of each hybrid, which might support the elaboration of a cost-effective irrigation plan.

    Our experiments were carried out at the Látókép Experimental Station of the University of Debrecen on calcareous chernozem soil in a small-plot long-term field trial with strip plot design. In the scope of the experiment, N-fertilizer doses were applied as basic fertilizer and top-dressing in addition to the non-fertilized (control) treatment. The 60 and 120 kg N/ha doses applied as basic fertilizers in the spring were followed by top-dressing in the V6 phenophase with a +30 kg N/ha dose. Measurements were carried out with the involvement of the Renfor early (FAO 320) and Fornad (FAO 420) late maturity hybrids-

    The stomata of the plants became more and more closed with the progression of the phenological phases; their stomatal conductance decreased. However, the hybrids responded differently to environmental stress. In the case of the Renfor hybrid, the highest conductance (669 mmol/m2-s) was recorded in the V12 phenophase with the 150 kg N/ha treatment. The stomata were more open due to the high turgor pressure, allowing plants to evaporate properly. The plant was in its worst physiological condition on 2nd July, at the time of the appearance of the last leaf in the case of the 120 kg N dose (224 mmol/m2-s). The value measured in the V12 phenophase has already shown that the stomata were closing due to the self-regulating system of the plant. It would have been necessary to dispense irrigation water following the measurement. This confirms the finding that water stress can be prevented by measuring stomatal conductance.

    In the case of the Fornad hybrid, stomatal conductance was the highest on 12th June (630 mmol/m2-s) in the 90 kg N/ha treatment and it was the lowest (183 mmol/m2-s) in VT (emergence of the last leaf) phenophase in the 60 kg N/ha treatment. In this case, the appropriate time for applying irrigation water would have been early July, when the conditions for the plants were still adequate. Subsequently, the stomata began to close due to a reduction of the water resources available to them.

    There was a significant correlation between soil moisture and stomatal conductance, as well as between temperature and stomatal conductance.

  • The relationship between the nutrient supply and the yield of maize hybrids with different genetic traits on chernozem soil in variant years
    27-31
    Views:
    196

    The experiments were set on lime-coated chernozem soil in 2013 and in 2014, in our study four hybrids were included with different FAO number. We studied the effect of NPK fertilization and row spacing on the yield. The fertilizer doses were based on a 25-year longterm experiment. Compared to control, the N40 +PK treatment has also achieved a significant yield increase, although some hybrids responsed with yield loss to the increasing fertilizer doses; this effect was observed especially in 2014. The majority of hybrids reached higher yields in both years using the 50 cm row spacing. The water release of hybrids was measured weekly during the maturation, at the same time points. The rainy September slowed ripening and the water release of the hybrids in 2013, so the grain wet content at harvest showed higher values. The moisture contents were increased for some hybrids, in spite of the positive and favorable dynamic of water loss.

  • Methodology adaptation and development to assess salt content dynamics and salt balance of soils under secondary salinization
    199-206
    Views:
    179

    The effect of irrigation with saline water (above 500 mg L-1) is considered a problem of small-scale farmers growing vegetable crops with high water demand in the hobby gardens characteristic of the Hungarian Great Plain. In order to simulate the circumstances of such hobby garden, we set up an experiment including five simple drainage lysimeters irrigated with saline water in the Research Institute of Karcag IAREF UD in 2019. We regularly measured the electric conductivity (EC) of the soil referring to its salt content and the soil moisture content with mobile sensors. Before and after the irrigation season, soil samples from the upper soil layer (0-0.6 m) were taken for laboratory analysis and the soil salt balance (SB) was calculated. The actual salt balance (SBact) was calculated of the upper soil layer (0-0.6 m) based on the salt content of the obtained soil samples. The theoretical salt balance (SBth) was calculated by the total soluble salt content of the irrigation water and leachates. During the irrigation season, we experienced fluctuating EC in the topsoil in close correlation with the soil moisture content. Based on the performed in-situ EC measurements, salts were leached from the upper soil layer resulting in a negative SB. Combining SBact and SBth of the soil columns of the lysimeters, we estimated the SB of the deeper (0.6-1.0 m) soil layer. We quantified 12% increase of the initial salt mass due to accumulation. We consider this methodology to be suitable for deeper understanding secondary salinization, which can contribute to mitigating its harmful effect. By repeating our measurements, we expect similar results proving that saline irrigation waters gained from the aquifers through drilled wells in Karcag are potentially suitable for irrigation if proper irrigation and soil management are applied.

     

  • Evaluation of nutrient conditions in open hydroponic system based on tomato production
    116-119
    Views:
    73

    Monoculture caused a gradual decline of soil conditions, while nematodes and salt accumulation stimulated the growers to choose alternative practices, such as soilless cultures, which proved their value in Western Europe. Exact statistics are lacking, but estimates deal with approximately 300-400 hectares of vegetable on rock wool, whereas other substrates of soilless culture may multiply this number. Real perspectives are attributed to the forced production of pepper, tomato and cucumber.
    Vegetable production in greenhouses may impair the ecological balance of the environment substantially as far as being uncontrolled. Soilless cultures especially should be handled thoughtfully. A fraction of the nutrients administered, more than 25-30%, is doomed to be lost in an open system, and the resulting ecological risk is accompanied with increasing costs of the production.
    In Hungary, the quantity of nutrient elements in drainage water is unknown, et all. Connecting the production results with chemical analysis, we gain more information about it.
    You can see a mathematical method for evaluation of nutrient and water conditions in tomato hydroponics production.

  • Land use, water management
    81-87
    Views:
    227

    Due to the prognosed population increase to 9.2 billion people by 2050, the world’s crop production does not have any other chance than to increase production. This demand is a huge challenge for agriculture. Based on the forecasts, the growth rate of production of the main cereals will decrease as a result of the effect of soil, water, the increasing fuel and fertiliser prices and the impacts of climate change. Methods ensuring sustainability have to be preferred. Precision agriculture is the most effective method of crop production. We have to apply minimum cultivation in order to protect the soil surface, maintain its moisture content and increase its water reception ability. In addition to the localised use of fertiliser, sowing seed, irrigation and pesticides, it is also important to apply them in a targeted way on the basis of plot imaging. The use of the new technology results in significant cost saving and it could also reduce environmental load.

  • Assessment of Environmental Susceptibility/Vulnerability of Soils
    62-74
    Views:
    91

    Soils 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.

  • Alternatives of microclimate control in orchards
    209-212
    Views:
    146

    The aim of the study was to find out which of the methods used to avoid damages of late frosts would be the most effective for the fruit growing practice. We tested the antifrost irrigation method in Debrecen-Pallag. For that purpose microjet sprayers are used, which are thrifty and does not need for that purpose large containers. With the aim to secure an even distribution of water, the sprayers are distributed on three levels: above and inside of the crown as well as on the level of trunks. On a large scale, a single microjet above the crown level would be sufficient. By means of a detailed analysis  served to set the optimum intervals between spraying phases: with each 15, 10, 5 and 3 minutes during half a minute. The synchronous presence of water and ice below the freezing point, the released freezing heat plus the water used much above the freezing point
    (9–10 °C) altogether maintains the temperature above around 0 °C near the flowers or growing fruitlets, meanwhile, the surrounding air cools down to -8 °C. The effectiveness of the generally used antifrost would be increased substantially by the former application of cooling irrigation, which delays the blooming date. 

  • Climatic water balance in Hamelmalo, Eritrea
    69-76
    Views:
    190

    Agricultural production is an important sector for peoples to live, but it is highly affected by climate change. To have a good production we need to understand the climatic parameters which adversely affect production. Hamelmalo, which is located in the semi-arid area of Eritrea, is vulnerable to climate change and this is realised in the total production loss. Nevertheless, there is no concrete reference about the climate of the region due to lack of data for a long time. Changes in precipitation (P), evapotranspiration (ET) and, implicitly, in the climatic water balance (CWB), are imminent effects of climate change. However, changes in the CWB, as a response to changes in P and ET, have not yet been analysed thoroughly enough in many parts of the world, including Eritrea. This study also explores the changes of the CWB in the Hamelmalo region, based on a wide range of climatic data (P, relative air humidity and evaporation pan necessary for computing potential evapotranspiration (PET) with the pan evaporation method) recorded at Hamelmalo from 2015-2019. This analysis shows that the annual cumulative CWB for Hamelmalo is negative in 67% of the years. The dry season without precipitation leads to negative CWB and the change in CWB only starts from the raining or crop season. Based on this recent study, 2015 had the highest PET and lowest P, and this resulted in the lowest CWB in the investigated period. Opposite to this, 2019 had lower PET and highest P, which led to the highest CWB. However, the monthly values of CWB did not correlate with the annual P or ET. On the base of our study, it can be concluded that PET and P were very variable in the investigated years and P was the most influential elements of CWB.

  • Measuring of nitrogen leaching using ceramic suction cups at different locations
    10-17
    Views:
    76

    Ceramic suction cups were used for the measurement of N-concentration in soil solutions under different soil and climate conditions in both field experiments of Rostock University and Agricultural University of Debrecen (Hungary). Depending on the soil utilisation the change in the N concentration of the soil solution can be proved on both sites.
    The experimental field of Rostock University can be characterised by its high groundwater table. The nitrogen concentration of soil solutions in the different soil layers were determined by the trend downward of water. In the dactylis (Dactilis glomerata) experiment, the quadruple treatments involved the following: with and without N-fertiliser, with and without harvesting, respectively. In the lower soil layers, the least rising N concentrations were established in case of the treatment without N-fertiliser combined with harvesting. The nitrogen leaching calculated from the infiltrated water quantity and the nitrate N concentration increased in the following order: without N-fertiliser, with harvesting < without N-fertiliser, without harvesting < with N-fertiliser, with harvesting << with N-fertiliser, without harvesting.
    The field experiment site of Debrecen can be characterised by a low groundwater table. The effect of N-fertilisation on the nitrate-N concentration of soil solution in the soil layers can be stated unanimously. Permanent nitrate-N leaching cannot be established due to the water upward movement under semiarid climate conditions. Intermittently transfer of nitrate-N between the soil layers is probable in cases of remarkable precipitation.

  • The Effect of Changes in Forest Area on the Transcarpathian Tisza River Basin
    181-185
    Views:
    72

    Forests are unique global factors which ensure life for almost every living being on Earth. They play a major role in controlling water flows, preventing erosion and controlling the oxygen content of Earth’s atmosphere. By the end of the XXth century, it was realized that forests help to nature maintain and are vital parts of our natural environment. By the time societies realized this fact, economic and environmental effects had amplified which endanger forests. Due to their good water control and water protection abilities, and their function in climate control, mountain forests can provide a suitable environment for themselves, for their successful growth.
    Forests play a major role in soil protection, especially in mountain areas where they prevent soil erosion. By converting surface waters into subsurface waters, forests help with the accumulation of subsurface waters, which are the sources of springs, rivers and streams. In the summer, they protect the soil from drying out by creating a special microclimate. They positively affect the climate of surrounding territories.