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  • Effects of water deficit on the growth and yield formation of maize (Zea mays L.)
    143-148
    Views:
    147

    Maize (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.

  • Researches regarding the influence of the some technological elements on water use efficiency in maize from Crisurilor Plain
    5-9
    Views:
    135

    Plain and the influence of the hybrid, plant density, crop rotation, nutrient supply, weeds and irrigation on water use efficiency were studied.

    Choosing of the hybrid with the best water use efficiency is very important because a hybrid from 500–600 FAO group (Fundulea 376) in unirrigated conditions and a hybrid from FAO group over 600 (Fundulea 365) obtained the biggest water use efficiency; the hybrid Fundulea 365 obtained the highest irrigation water use efficiency, 20.1 kg yield gain 1 mm-1 irrigation water.

    One of the most known hybrid in the area is Turda super and the highest water use efficiency was obtained using the plant density of 55 000 plants/ha in unirrigated variant and 70 000 plants/ha in irrigated variant. The highest irrigation water use efficiency, 20.7 kg yield gain 1 mm-1, was obtained at 70 000 plants ha-1.

    In maize monoculture was obtained the lowest values of the water use efficiency in unirrigated and irrigated variant: in the wheat-maize crop rotation the values were higher than in maize monoculture and in the wheat-maize-soybean were registered the highest values. The same situation was registered regarding the irrigation water use efficiency.

    Farm manure (30 t ha-1) and especially manure (30 t ha-1) +chemical fertilizers (N90P45) determined a higher values of the water use efficiency in comparison with the control. In the variant with organic + mineral fertilization was registered the higher value (19.4 kg yield gain mm-1) of the irrigation water use efficiency.

    Water use efficiency was much lower in the variant with weeds in comparison with the variant without the weeds; the differences were of 69% in unirrigated variant and of 64% in irrigated variant, very significant statistically. Irrigation water use efficiency from variant with weeds was lower than the value registered in the variant without weeds; the difference (68%) was very significant statistically.

    In average in period 1976–2012, the irrigation determined the increasing in water use efficiency with 22%, 19.4 kg mm-1 vs. 15.8 kg mm-1, but not in all the years caused the irrigation increasing in water use efficiency in comparison with unirrigated maize.

    The results research emphasized the need of the optimization for technology elements studied and a better water use efficiency will be obtained.

  • Water relations composition among Egyptian cotton genotypes under water deficit
    5-15
    Views:
    153

    Background: water shortage is one of the major factor effects on growth characters and yield of most crops. Objective: this study was conducted to get to know the reactions of some Egyptian cotton genotypes to water deficit. Methods: The genetic materials used in this study included thirteen cotton genotypes belonging to Gossypium barbadense L., from the Cotton Research Institute (CRI), which was devoted to establishing the experimental materials for this investigation. Results: the ratio of GCA/SCA was less than unity for all studied indices, indicating predominance of non-additive gene action (dominance and epistasis), which is an important in exploitation of heterosis through hybrid breeding. Results: The data showed significant reduction in water relationship characters for all parental genotypes under stress conditions. The Egyptian variety Giza 68 gave high values for most water relationship characters. Data revealed that the greater the value of tolerance index is, the larger the yield reduction is under water deficit conditions and the higher the stress sensitivity is becoming. The parental genotypes Giza 96 showed the highest reduction in yield under water deficit conditions. At the same time, the cross combination Minufy x Australy showed higher values of yield reduction followed by the combinations Giza 67 x Australy. Of the male parents, the Russian genotype 10229 recorded the best GCA values for most water relationship characters. At the same time, the female parents, the old Egyptian genotype Giza 67 recorded the best values and exhibited good general combined for most water relationship characters. The cross combinations Giza 86 x Pima S6, Giza 77 x Pima S6, Giza 94 x Dandra and Giza 96 x Australy showed significant desirable SCA effect for most characters. Conclusion: relative water content %, osmotic pressure, chlorophyll and carotenoids content indicates better availability of water in the cell, which increases the photosynthetic rate. Also, the higher level of proline accumulation in the leaves which was recorded under deficit water suggests that the production of proline is probably a common response of plant under water deficit conditions.

  • Long term researches regarding the irrigation influence on sugarbeet crop inthe Crisurilor Plain
    11-15
    Views:
    109

    The paper is based on the researches carried out in the long term trial placed on the preluvosoil from Agricultural Research and Development Station Oradea, Crisurilor Plain in during 1976–2012.

    The soil water reserve in 0–75 cm depth decreased bellow easily available water content every year and in 32% of years the soil water reserve decreased bellow wilting point. For optimum water supply an irrigation rate of 2665 m3 ha-1 (variation interval 500–5090 m3 ha-1) was needed.

    The irrigation determined improving of water/temperature + light report (Domuta climate index) with 47.4% in average in the period May–September. A statistically very significant connection was quantified between this indicator and the yield.

    Daily water consumption increased in the irrigated variant, the biggest difference in comparison with unirrigated variant was registered in August, 86% in comparison with unirrigated variant. As consequence, the value of the total water consumption increased with 50%, variation interval was 11–154%. The irrigation covered 37.8% of total water consumption, the variation interval was 8.3%–67.9%.

    The yield level of the sugarbeet increased in average with 61%, the variation interval was 9–227%. Standard deviation was lower in the irrigated variant and this emphasizes an improve of the yield stability with 25.1%. The sugar content of the sugarbeet roots from irrigated variant increased statistically very significantly in the droughty years and differs significantly in the rainy years.

    Water use efficiency increased in the irrigated variant with 7% and irrigation water use efficiency was between 7.9 kg yield gain 1 m-3 irrigation water and 17.4 kg yield gain 1 m-3 irrigation water.

    The positive influence of the irrigation on microclimate, water consumption, yield level, stability and quality and on water use efficiency sustain the need of the irrigation in sugarbeet from Crisurilor Plain.

  • Characterization of Water Resources in Transcarpathia
    277-281
    Views:
    85

    Transcarpathia is located in one of the wettest parts of the Ukraine. There are 9429 rivers and creeks in the county with a total length of 19.86 thousand kilometers. The length of 152 rivers exceeds 10 km, 4 exceed 100 km (Tisza, Latorca, Ung and Borsava rivers). The average density of rivers is 1.7 km/km2, which is the highest in the Ukraine. The existing water resources are distributed unevenly in the county. The river with the greatest mass of water is the Tisza. Tisza carries 75% of all existing water resources, the remaining 25% is made up of the water in the river Ung and Latorca. Disregarding the uneven distribution of water resources, 80% of water is used up in the basins of the rivers Ung and Latorca from the water resources of the county, which leads to the overload of rivers.
    The main sources of water supply in Transcarpathia: subsurface waters – for the population of cities and settlements, surface and subsurface waters – for the industry, surface waters – for irrigation.
    In the interest of protecting existing water resources, it is required to follow current regulations, detecting and averting contaminating sources and establishing water conservation zones.

  • Agricultural aspects in river basin management plans
    149-152
    Views:
    89

    In the European Region agriculture is the second largest water user after power industry cooling water use. As part of the implementation of Water Framework Directive EU Member States prepared their river basin management plans by the end of 2009 or first half of 2010, In these plans impacts of agriculture on water bodies have received attention. The detailed information elaborated in the plans by countries and river basin districts were uploaded into the WFD section of the WISE system. This database provides opportunity for multi-criteria analysis for different water types. The paper discusses the effects of agriculture on hydromorphological pressures and impacts affecting surface water bodies. It was pointed out that among the pressures affecting European surface water bodies the hydromorphological and diffuse pressures represent the highest ratios (Figure 1). Within the hydromorphological pressures affecting classified surface water bodies the ratio of pressures related to agricultural activities is low,
    it does not exceed 1% at European level. In case of Hungary the agriculture related river management pressures effect about 80% of the surface water bodies, which is much higher than the corresponding European average. The agricultural water abstractions affect about 10% of the Hungarian surface water bodies (Figures 2 and 3). The river and lake water bodies are impacted in significant ratio by nutrient enrichments and organic material enrichments, while in case of river water bodies the impact of organic material enrichments is also significant (Figures 4 and 5).

  • Circumstances of the establishment of the Eastern Main Channel, water utilisation problems and alternatives
    79-84
    Views:
    94

    After hundreds of years of drought in the area of Hortobágy and its surroundings brought up the idea of building a channel in Tiszántúl. It started with the idea of an irrigation canal but it ended up in a canal with high importance which can be used in many ways. Because of financial problems the necessary renovations cannot be achieved, and as a side effect the amount of silt in the water started to increase, water exploitation started to decrease, and the construction works started to get spoiled. Guided by the Water Directive the East Main Channel has become one of the most significant surface water base in Hungary. To use its water as drinking water brings up a few questions, like solving the pollution problems which problems have already occured. If we want the East Main Channel to be a solution for a long time, further steps and researches are needed to solve the problem of diverting the huge amount of precipitation of the last few years and miantaining the quality of drinking water.

  • The Impact of Water Supply on the Quality and Health of Potato
    144-147
    Views:
    102

    Besides its effect on potato yield, water also has a significant impact on yield quality. Excess water (too much precipitation, over-irrigation) and the lack of water (lack of precipitation or irrigation) both trigger stress in the plant and can significantly worsen the quality of the yield (seed potato) and deteriorate the health of the plant and the seed potato. Excess precipitaton or irrigation water leaches nitrate-nitrogen under the rhizosphere, consequently, the amount of available nitrogen decreases leading to the deficiency of N in potato. If water cover (the maximally saturated state of soil) exceeds 8-12 hours, it can cause root destruction (because of the lack of oxygen), which leads to the wilting and later to the death of the plant. Abundance of water caused by excess precipitation or irrigation is a major problem primarily on sandy loam, loam and clay loam soils with bad structure and water management qualities, but also on any soils, which are over-irrigated or irrigated at an improper time. Symptoms of the lack of water are detectable mostly when the available water content of the soil (disponible water) decreases under 60-65%.
    In the present year, there was a lack of precipitation on the Great Plain, which can be compensated by proper irrigation. Unfortunately, this problem is further intensified by the high temperature, which results in faster ripening and accompanied with fluctuating soil moisture content, in the formation of secondary tubers.

  • Application of AquaCrop in processing tomato growing and calculation of irrigation water
    183-187
    Views:
    290

    The area and volume of processing tomato production is increasing in Hungary. Irrigation is crucial for processing tomato growing. To save water and energy, it is important to know exactly how much water is needed to reach the desirable quality and quantity. AquaCrop is a complex software, developed by FAO, which is able to calculate irrigation water needs, several stress factors and to predict yields. A field experiment was conducted in Szarvas in processing tomato stands, under different irrigation treatments. These were the following: fully irrigated plot with 100% of evapotranspiration (ET) (calculated by AquaCrop), deficit irrigated plot with 50% of ET (D) and control (K) plot with basic water supply was also examined. Dry yield, crop water stress index and soil moisture were compared to modelled data. The yields in the plots with different access to water were not outstanding in the experiment. The model overestimated the yields in every case, but the actual and modelled yields showed good correlation. AquaCrop detected stomatal closure percentages only in the unirrigated plot. These values were compared to CWSI – computed from leaf surface temperature data, collected by a thermal cam in July – and showed moderately strong correlation. This result suggests that Aquacrop simulates water stress not precisely and it is only applicable in the case of water scarcity. Soil moisture data of the three plots were only compared by means. The measured and modeled data did not differ in the case of K and ET plots, but difference appeared in the D plot. The obtained results suggest that the use of AquaCrop for monitoring soil moisture and water stress has its limits when we apply the examined variables. In the case of dry yield prediction overestimation needs to be considered.

  • Risk effects of the spread route of mycotoxins
    90-95
    Views:
    89

    In Hungary the mycotoxin is a great problem, because there are many natural toxins in wheat and maize. These cereals can be found on
    considerable proportion of the country’s sowing area, and they are deterministic food for the population. The direct human and animal
    utilization of the contaminated cereals mean a serious risk in the food chain. In Hungary’s climate the soil is contaminated with pathogen
    moulds, particularly Fusarium species, which increase by respective temperature and moisture content in cereals. The Fusarium can
    decrease the quality of the wheat in different ways: decrease the germination capability and cause visible discoloration and appearance of
    mould, reduces the dry material and nutrient content of the grain. From the toxins produced by the Fusarium genus, the trichotecene (T-2,
    HT-2, deoxinivalenol, nivalenol, diacetoxyscxirpenol, Fusarenon-X) and the estrogenic zearalenon (F-2) are the most common in Hungary.
    The fumonisins (FB1, FB2, FB3) first identified in 1988, relatively newly discovered, are also important. Major proportion of mycotoxins in a
    healthy organization is metabolized by the enzyme system of liver and intestinal bacteria. The toxicity is reduced or even leaves off.
    However, more toxic and biologically active compounds can be formed. For the reduction of mycotoxin-contamination several possibilities
    are available in the case of storage, processing and feeding.

  • Effect of hail net on the water potential of an apple orchard
    109-113
    Views:
    129

     Apple production has seen a decline in yields in recent years, primarily due to ecological factors such as drought, water stress, water scarcity, uneven rainfall distribution, frost damage and hail damage. Ecological factors that are harmful to the plant can be eliminated by human intervention, irrigation or the use of hail net. In our study, we investigated the positive effects of hail net on the development of plant water potential as the vegetation progressed, in non-irrigation area with temperature and humidity. Water potential values were determined using a field osmometer. Confirmed the positive effect of the ice protection net in the apple orchard of Early Gold and Golden Reinders. Our results were supported by statistical analyzes our results.

  • Characterisation of basic water balance parameters of Debrecen
    35-40
    Views:
    148

    This work aims to develop a hydrological modelling tool to help managers make the right decisions for Debrecen, in the face of water scarcity and the increase in agricultural and domestic needs over time. The methodology was based on the creation of a climatic database, at monthly time steps, from 2016 to 2019, and cartographic (land use, digital elevation model, and hydrological network). As a next step, the watershed was delimitated into sub-basins to determine the shape and the physiographic characteristics of sub-watersheds. Finally, a hydrological study was prepared by calculating the time of concentration to build a database of water resources in the study area. This water resource will be used as an input parameter for urban farming.

  • Conceptional Model of Regional Agricultural Water Management System
    199-209
    Views:
    90

    Our study focuses on the water management improvement of the Hajdúsági-löszhát (loess ridge). The Hajdúsági-löszhát (loess ridge) is an intensive agricultural area. At the same time, the problem of increasing water demand is still not solved, so towards of safety production irrigation should be improved. To realise this should be known not even agricultural water demands but industrial and urban ones as well, thus a complex water management system is required to be worked out.
    In the first part of the research, the water demand in the area is mapped, then a conceptional model of the Hajdúsági-löszhát’s (loess ridge’s) water management system is created. After collecting data the water management scenario is summarized in a real time model splitted into five periods.
    During the research, the instruments of spatial informatics (GIS) are used to get acquainted with the variation of the hydrological parameters in space and time. To understand and simulate the different decision making processes and to choose the right decision alternative, a decision support system is created with the use of spatial informatics data.
    In addition, considering the potentially right decision alternative, irrigation will be started in practice, an effect and after-effect inquiry will be made, and the results will be analysed, evaluated and summarized. Finally, a suggestion to the most adequate irrigation technology will be made.

  • The Role of the Digital Terrain Models in the Assessment of Surplus Water Risk at the Szolnok-Túri Plain
    47-51
    Views:
    94

    The environmental factors to which surplus water can be assigned (topography, soil, groundwater, vegetation etc.) can be subject to special analysis and the randomness of the occurrences can be limited. The results of these procedures are surplus water risk maps of the areas, which can be utilised in land use planning. The risk map of the research site was created with overlaying digital category maps of the determining factors (hydraulic conductivity, convexity, critical probability of ground water level and land use).

  • Regulation in Hungary of the Use of Waste Water and Sewage Sludge in Agriculture
    143-149
    Views:
    100

    Regulating 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.

  • Implementation alterantives of the CIVAQUA complex water management program in the Debrecen region
    71-73
    Views:
    115

    Hungary is one of the countries in Europe which has the largest amount of water supply because of its geographical conditions. Water comes from the surrounding mountains makes this water supply even more bigger. This precious water base needs to be treated responsibly and the most efficient way. The Civaqua program is a project with the above-mentioned conditions, made by the Local Government of Debrecen and the Water Directory of Trans-Tiszanian Region. This project deals with the exploitation of the East-Main Chanel’s water for social welfare, agricultural and inverimental protection purposes in Debrecen and its agglomeration. The aim of this paper is to give an overall insight into the investment plans of Civaqua program and it is also examines its positive direct and indirect effects on the region.

  • Effect of sufficient and deficit irrigation with different salt inputs on the yield of cucumber
    19-25
    Views:
    50

    Soil salinisation is considered one of the major environmental hazards threatening agricultural productivity and can be accentuated by climate change as well as the use of low-quality water in irrigation. This is the case in our study area which is affected by secondary salinisation due to the use of saline irrigation water for horticultural production. Deficit irrigation technique is implemented especially in arid and semiarid regions due to its potential to optimise water productivity while maintaining or increasing crop yield. The main objective of this study was to compare the effect of irrigation with sufficient (SD) and deficit (DD) doses. This research was carried out in Karcag in 2020. Cucumber was grown on a meadow chernozem soil and was irrigated with SD and DD of two irrigation water qualities. Soil moisture was monitored and crop yields were recorded. Despite the differences in quality and quantity of water, the application of less water by DD maintained the same yield as SD. We found a non-significant difference between the average soil moisture contents under the treatments (15.5 v/v% for SD and 13.5 v/v% for DD). Deficit irrigation can be an efficient technique due to its potential for improving water use efficiency, maintaining sufficient soil moisture content favourable for proper crop development and yield.

  • Experiments on the Nutrient Removal and Retention of an Integrated Pond System
    18-23
    Views:
    183

    A combined intensive-extensive fishpond system developed for the purification and re-use of intensive fishpond effluent water was studied during a three-year experimental period. The investigated pond system consists of five small-size intensive culture ponds of 1 ha total water surface area with 1.5 m water depth and a 20 ha extensive culture pond with 1.0 m average water depth. The water was recirculated between the intensive and extensive ponds with around 60 days retention time in the extensive treatment pond.
    Carbon, nitrogen and phosphorus budget and water purifying capacity were described and evaluated by means of regular measurements of nutrient concentrations in the water and sediment. During the three-year test period, 81.5% of organic carbon, 54.7% of nitrogen and 72.2% of phosphorus were retained by the system as a percentage of the total input of each nutrient. A significant amount of the total nitrogen input was removed by the harvested fish, which was much higher than in traditional fishponds or intensive fish culture systems. The efficiency of nutrient removal is clearly indicated by the 27.3% nitrogen assimilation.
    Only a small percentage of the total nutrient input was discharged into the environment during fish harvest, which was 9.0% for organic carbon, 13.2% for nitrogen and 12.1% for phosphorus. The combination of intensive and extensive fishponds with water recirculation resulted in significant reduction of nutrient discharge into the surrounding aquatic environment, primarily due to the high nutrient processing and retention capacity of the extensive fishpond ecosystem.

  • Examination of the conditions of extreme water balance circumstances (water logging, drought) with environmental information technology tools
    79-86
    Views:
    185

    The Carpathian Basin is characterized by varying hydrological extremes, both in space and time. Hungary's natural endowments are more favourable than average, especially for agricultural production, with 5,3 million hectares of land we have which is suitable for agricultural production. These extreme water management are often occur in the same year and mostly in the same region, which may become more frequent in the future, especially in the lowland regions. The negative impacts of extreme water management was influenced by the land use changes in recent years, which has modified the runoff processes of the affected regions.

    The aim of the study was to research the formation of inland water and drought circumstances in two sample areas the Great Plain (Szolnok-Túri flat and Nyírség) by geoinformatic tools. During the investigation in the first step we determined that areas which are susceptible to inland water and drought, based on the AGROTOPO database. In addition, land-use categories of characteristics of the sample areas are evaluated according to the Corine Land Cover. Furthermore, after defining characteristic of NDVI values between the period of 2003–2013, we evaluated the effect of drought whether can be detected in crop failures in respective areas.

    Based on our results, we concluded that the formation of inland water and drought circumstances can be investigated in a large spatial extension by geoinformatic tools and databases.

  • Correlations of the global, regional and local factors of the anthropogenic effects on the water reserves of the Earth’s crust
    85-92
    Views:
    98

    The decrease in Earth's drinking water resources and the degradation of its quality has become a critical problem. Our planet's total water supply is estimated to be around 2 billion km3s. This is only 1% of Earth's own weight. Of this small amount only a tiny 3% is fresh water, of which 79% is forzen in glaciers and 1% is present as surface waters.The ratio of water stored in soil is around 20%. This is 0.2% of the total water supply. Our study aims to summarize the layered groundwater aquifer systems and its changes which are the results of anthropogenic effects in both global and hungarian respects and also for the region of Debrecen.In particular with regard to the geological and ecological level where irreversible
    processes take place. All this is discussed in the context of cause and effect. Pointing out the dangers of excessive deep groundwater extraction and the contamination caused by toxic substances that are the byproducts of modern life. In addition we discuss the Water Directive of the European Union which gives a policy for community action concerning the goal to achive the status of „in good condition” for our waters till 2015.

  • Dilemmas of consumption habits - comparison of the quality of bottled mineral water and the public utility drinking water in Debrecen
    217-221
    Views:
    101

    This paper tries to help to decide whether the bottled mineral water or the piped water is more advisable for consumption in Debrecen and in its regions, according to the aspects of environmental awareness and aspects of health, beside the venture of representing the functions of water in our lives and its global importance.

  • Comparative Study on Different Water Bodies and their Sediments
    17-21
    Views:
    66

    Hungary is rich in natural water resources, therefore investigation of these biotopes is an important task. The Szarvas- Kákafok deadarm is the largest horse-shoe lake of the Tiszántúl, its lenght is 28 km. It has an important role in recreation and agricultural utilization. The quality of the deadarm is influenced by the river Körös, but also by communal and agricultural pollution. Our goals were to estimate the intensity of the
    sedimentation processes, and the water- and the sediment quality as well. Also, we examined an artificial wetland system, constructed by the Fish Culture and Irrigation Research Institute, Szarvas.
    The calculated sedimentation was 0.4-0.5 cm year-1, which indicated an intensive eutrophication process. The constructed wetland system was able to decrease the organic load of the intensive fish culture company. On the basis of our TOC measurements, the organic matter content of the effluent water remained whitin the water quality limits.
    The changes of the material cycling could be more intense in the water body, then in the sediment. The oxido-reduction potential of the sediment could indicate the ecological state of the shallow lakes, therefore it could be an easily measurable indicator in the water classification.

  • The history and present of public drinking water supply and its regionalisation in Debrecen
    147-151
    Views:
    144

    The public water supply played a major role in the urbanization of Debrecen city, just like in the case of many other cities. We had plenty of water and so we wasted it. However nowadays we experience a considerable decrease in the level of groundwater which causes an increasing need of energy for pumping. Beside the above mentioned the ecological threat and the decreasing water quality are also major problems. This study attempts to draw attention to the possibilities and the future of the regional water supply, by showing the history of the water supply, the sanitation systems of Debrecen and their present day activities.

  • Examination of extreme water-balance of maize cultivar in different crop rotation systems in 2007
    33-40
    Views:
    65

    We examined the change of the time of water balance of soil in long-term experiment, on chernozem soil, in different croprotation systems (mono-, bi- and triculture). We found the smallest difference between the water deficit of not irrigated and irrigated plots in triculture. We concluded that irrigation impressed favourably on water balance of soil in both of crop-rotation systems. Water deficit has decreased significantly after irrigation
    in 25. May in mono- and triculture. Irrigation moderated only values of water deficit. Irrigation in 30. June not influenced water balance of soil in both of crop-rotation because of a big drought. Water deficit of soil lessed till harvestperiod because of rainy season at the end of August and in September.

  • Seed biology and possibility of improvement of seed germination capacity on Virginia mallow (Sida hermaphrodita L. Rusby)
    71-76
    Views:
    136

    Sida hermephrodita or Virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through the last two decades. Additionally, the plants have a lot of uses and benefits for instance it can use as a fodder crop, honey crop, ornamental plant in public gardens. It has favourable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in the beginning phase of domestication therefore it has a serious disadvantage: the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seeds/acre instead of 10–20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a available, basically wild Sida population. In the first stage of our experiments we examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenous or endogenous infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65 oC, 80 oC, 90 oC), from 29,3% to 46% germinated from those samples which were collected from the population of Sida hermaphrodita in Debrecen. The average germination for all season was 5–10% without treatment and rinsed using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46%) after the hot water operation in spite of the previous studies. We discovered that apparently there are close relationship between the seed fresh weight or water uptake capability and the percentage of infection. Following these recognition we modified our technique,in such a way that we fractionated the seeds based on their fresh weight/or relative density before we carried out the treatment. When we filtered the floating seeds on the surface of water, the hot water treatment was performed considerably better on the sunk seeds after separation. Therefore, by this special priming process we were able to reach 80% germination capacity of Virgina mallow seeds under laboratory conditions (26 oC without illumination).