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GC-MS studies to map mechanistic aspects of photolytic decomposition of pesticides
11-16Views:82Transformation of pesticides in the environment is a highly complex process affected by different factors. Both biological and physical-chemical factors may play a role in the degradation, whose ratio depends on the actual environmental conditions.
Our study aims to reveal specific details of photolytic degradation of pesticides as important soil contaminants. Significance of these studies is enhanced by the fact that pesticide decomposition may contribute to soil degradation, and have harmful biological effects by degrading to toxic products. The toxicity of the examined pesticides is well known, however very little information is available regarding their natural degradation processes, the quality, structure and biological impact of the degradation products.
The photolytic degradation of frequently applied pesticides of distinctive types (acetochlor – acetanilide, simazine – triazine, chlorpyrifos – organophosphate, carbendazim – benzimidazole) was investigated. A special, immerseable UV-light source was applied in order to carry out photodegradation. The degradation processes were followed by thin layer chromatography (TLC) and mass spectrometry coupled with gas chromatography (GC/MS). EI mass spectrometry was used to identify the degradation species.
Each of the studied pesticides underwent photolytic decomposition, and the detailed mechanism of photolytic transformation was established. At least four degradation species were detected and identified in each case. Loss of alkyl, alkyloxy, amino-alkyl and chloro groups might be regarded as typical decomposition patterns. Deamination occurred at the last stage of decomposition. -
Assessment of Environmental Susceptibility/Vulnerability of Soils
62-74Views:90Soils 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. -
Grassland association stock of plants the examination of the regeneration of a construction
185-191Views:35Due to the drastic change in using the nature like grassland association (one-sided overgrazing – one mowing per a year), by the third year of the experiment in every area, where overgrazing stopped, independently on second sowing and nutrient resupply, Borhidi degradation degree decreased. In the areas where overgrazing with large animal density (sheep) continued, degradation degree was 3.4–5.0 by the third year of the experiment, and Hordeum murinum, which causes animal healthy problems, appeared massively.
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Evaluation of Soil Degradation Based on High Resolution Remote Sensing Data
145-148Views:89Soil 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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Sequence stability at SSR, ISSR and mtDNA loci of common millet (Panicum miliaceum) from the middle ages
10-19Views:95Seed remains of medieval millet, recovered from a 15th century layer (King’s Palace, Budapest, Hungary), showed reddish yellow grain color after rehydrating on tissue culture medium that was close to grain color of modern cultivar Omszkoje. aDNA of medieval c. millet was extracted successfully, analyzed and compared to modern common millets by ISSR, SSR, CAPS and mtDNA. Analyses of fragments and sequences revealed
polymorphism at seven ISSR loci (22 alleles) and at the 5S-18S rDNA locus of mtDNA. CAPS analysis of the 5S-18S rDNA fragment revealed no SNPs in the restriction sites of six endonucleases TaqI, BsuRI, HinfI, MboI, AluI and RsaI. Sequence alignments of the restriction fragments RsaI also revealed
consensus sequence in the medieval sample compared to a modern variety. Morphological characterization of twenty common millet (Panicum miliaceum L., 2n=4×=36) cultivars and landraces revealed four distinct clusters which were apparently consistent with the grain colors of black, black and brown, red, yellow, and white. In the comparative AFLP, SSR and mtDNA analysis modern millet cv. ‘Topáz’ was used. AFLP analysis revealed that extensive DNA degradation had occurred in the 4th CENT. ancient millet resulting in only 2 (1.2%) AFLP fragments (98.8% degradation),
compared to the 15th CENT. medieval millet with 158 (40%) fragments (60% degradation) and modern millet cv. ‘Topáz’ with 264 fragments (100%). Eight AFLP fragments were sequenced after reamplification and cloning. Microsatellite (SSR) analysis at the nuclear gln4, sh1, rps28 and rps15 loci of the medieval DNA revealed one SNP (single nucleotide polymorphism) at the 29th position (A to G) of rps28 locus compared to modern millet.
Mitochondrial (mtDNA) fragment (MboI) amplified at the 5S-18S-rDNA locus in the medieval millet showed no molecular changes compared to modern millet. The results underline the significance of survived aDNA extraction and analysis of excavated seeds for comparative analysis and molecular reconstruction of ancient and extinct plant genotypes. An attempted phenotype reconstruction indicated that medieval common millet showed the closest morphological similarity to modern millet cultivar Omszkoje. -
Pre-treatment of wastes containing keratin in industrial conditions
59-64Views:123The aim of the research was a development of a featherdegradation technology in industrial circumstances. During the experiments we determined the parameters of the critical environmental and technological limitation factors. Because of the high keratin-content the degradation (and composting) of the feather is difficult. With the developed technology huge mass of feather can be used fast and easily in biogas production and in the adjustment of the optimal element ratio of biomass. The industrial experiments were implemented in a 6m3 heatable double-walled
tank with stirring-shovels and aeration-system. The degradation process was followed with extinction measurements.
According to the experiments that were done the best results were given at the case which was heat-treated at 70°C, was injected with 1% bacteria concentration, and where 1:3 feather:water ratio was set if we consider the effectiveness of degradation and the hydraulical retention time. -
Long-term effect of soil management on the carbon-dioxide emission of the soil
515-527Views:99CO2 emission from soils is one of the most important elements of the global carbon cycle, thus it has crucial rule in climate change. Each soil cultivation operation intervenes in the microbiological life of the soil, hence tillage is a factor through that the processes taking place in soil can be controlled. During the last decades, the organic material content of agricultural soils decreased to the half due to the intensive management resulting in the degradation of natural soil fertility. While intensive, plough-based tillage can cause soil degradation and erosion, the physical, chemical and biological status of the soil can be significantly improved through the application of conservation tillage methods. The results of long-term experiments prove that soil protective tillage enhances the enrichment of organic matter in the top layer of the soil. In order to reveal the role of tillage systems in CO2 emission from the soil, regular measurements were carried out in the plots with conventional and reduced tillage of the soil cultivation experiment of Research Institute of Karcag. Anagas CD 98 and Gas Alert Micro 5w infrared gas analysers were used to measure CO2-concentrations, and a specially developed method (consisting of a frame and a bowl) was applied to delimitate the measuring area. Most of the measurements were done on stubbles after harvest in order to exclude root respiration. The weather conditions of the examined 10 years were very changeable providing a good chance to compare them to each other. We found the tillage operations resulting in higher emission values in both tillage systems. On stubbles higher and more even emission was characteristic to reduced tillage due to the lower degree of soil disturbance and higher soil moisture content.
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Urgent agricultural issues of soil protection
169-172Views:143The primary aim of this study is to draw attention to the importance of legal problems of soil protection. The basis for my study is the ombudsman’s 2016 principle of soil protection. This resolution summarizes the most pressing soil protection measures in 15 points that need to be taken as soon as possible to preserve soil resources. To narrow the wide range of topics, I will examine three points: (1) preservation of soil resources, (2) soil sealing, (3) brownfield instead of greenfield. Hungary is in a special position concerning this most ancient natural resource, as only 11% of all the land covered area of Earth consists of soil, the EU average is less than 30%, while in Hungary it is more than 60%. Despite the existing protective legal requirements, soil degradation is a constant issue. The persistence of population growth spells the need for more arable land, but as a result of the stressful impacts caused by people we are running out of useable topsoil.
Assessing both the short and long term process of land reclamation, it can be stated that more and more farmland becomes permanently and imperviously covered for other purposes each year, and as the arable land area decreases, the impervious surface area grows despite all respective decisions, regulations and prohibitions.
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Global Issues of RangelandManagement
39-46Views:105Rangelands occupy about 50% of the world’s land area. They are ecologically and economically as important as rain forests and in even greater danger of degradation and disappearance. This paper reviews the definitions and distribution of rangelands and describes their global environmental importance in terms of erosion control, carbon storage and methane emission. Condition and degradation of rangelands are defined and discussed and it is argued that soil protection and carbon storage can be increased and methane emission per animal decreased by conservative use and improvement of rangelands, whilst at the same time alleviating hunger and malnutrition in developing countries. It is concluded that policies should be adopted by national governments and international deve-lopment programs to conserve and improve rangelands.
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Effect of Silver willow “Russian olive” (Elaeagnus angustifolia) on extensive sheep management
157-162Views:70We carried out a study in the Karcag Research Institute, which affected the areas of narrow-leaved silver willow. In the framework of this research, we performed Balázs's coenology, and thus established the degree of Borhidi degradation, which resulted in the fact that the areas of the silver willow were degraded practically irreversibly, the diversity of the grassland has decreased. We consider it very important to study these grassland areas of silver willows, as they can provide an additional fodder base for sheep grazing, which will also increase the sustainability of the grassland. The obtained soil analysis results show that the soil samples of the silver willow areas are richer in nitrogen (p-value: 0.006) and phosphorus (p-value: 0.003) than the examined control area.
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Methodological development of the determination of the compost mixture ratio
29-33Views:77The mixing rate of the compost raw materials basically determines the procedure of degradation. In most cases, in practice the real mixing ratio is not equal with the counted ratio – which based on the C/N ratio – and the check of the fulfilled mixing is not possible.
The homogeneity of the prism is also one of the fundamentals of the effective degradation process. There is no available method to determine the homogeneity of the compost prism.
During our research we examined the reflectance values of different compost mixtures where sewage sludge and rape-straw were used as raw materials.
According to our results we built up a regression model which gives the ability to determine the mixing rate (in 5% margin of error) and makes possible to check the homogeneity of the prism together with the access of immediate action. -
Analysis of aerobic biological waste treatment methods especially in the case of composting
33-37Views:146In recent years the regulations of the EU unambiguously determine that the biodegradable wastes should be used in agriculture. The characteristics of the organic wastes in most cases make the direct utilization impossible, they need pre-treatment before use. One treatment solution of these wastes is composting. During composting the organic wastes lose their hazardous characteristics and we gain a final product, the compost, which can be used in agriculture as organic fertilizer. The main conditions of effective composting are the follow and understand of the degradation process. During our research we examined different measuring methods (gas concentration and reflectance measurements, temperature mapping) that makes a cost and time effective possibility to directly analyze the degradation.
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Soil – Environment – Sustainability
331-337Views:181The future and life quality of human society depends primarily on the success of the sustainable use of natural resources: the geological strata–soil–water–biota–near surface atmosphere continuum. Soil is the most significant conditionally renewable natural resource in our Earth’s system, with three unique properties: multifunctionality; fertility/ productivity; resilience. In the case of rational land use and precise soil management soil does not disappear, and its desirable „quality” does not decrease considerably, irreversibly and unavoidably. Its renewal, however, requires continuous care and permanent activities.
Consequently, the prevention, elimination or moderation of soil degradation processes and extreme hydrological situations (the two main factors limiting desirable soil multifunctionality) with rational land use and soil management are the key factors and priority tasks of sustainable development on each level and in each phase of the decisionmaking process. -
Comparative examination of the tillage systems of maize on meadow chernozem soil
21-24Views:167Maize production plays a major role in the agriculture of Hungary. Maize yields were very variable in Hungary in the last few decades. Unpredictable purchase prices, periodical overproduction, the increasing occurrence of weather extremities, the uncertain profit producing ability, the soil degradation processes (physical, chemical and biological degradation) and the high expenses are risk factors for producers. Due soil tillage, there is an opportunity to reduce these risks. Based on the experimental database of the Institute of Land Utilisation, Regional Development and Technology of the University of Debrecen, Centre for Agricultural and the KITE Plc., various cultivation systems were examined with maize (Zea mays L.) as indicator plant in Jász-Nagykun-Szolnok country in 2012 and 2013. The sample area can be found in the outskirts of Kenderes on a meadow chernozem soil. On the examined plot, strip-tillage, subsoiling and moldboard ploughing were performed, each on 4.5 ha, respectively.
In general, our findings show, that strip-tillage and subsoiling can be alternative tillage systems beside moldboard ploughing on meadow chernozem soils in Hungary.
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Optimized balance between crop productivity, restoration and maintenance of vital soil functions and soil carbon sequestration and storage – the SmartSOIL (FP7) project
213-215Views:96Soils 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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Analysis of the Environmental Status of Nagykálló Subregion
362-367Views:93The 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.
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Anaerobe degradation of maize infected by Fusarium graminearum
57-61Views:142Last year intense rainfalls and moisture conditions were beneficial for the Fusarium sp. in Hungary. Fusarium strains decrease cereal quality (for example maize), furthermore may cause yield loss. Due to the toxin production, the fungi have a dangerous animal and human pathogen effect (Placinta et al., 1999).The effects of the Fusarium infection and its mycotoxin production haven’t been perfectly eliminated. Fusariumgraminearum
is the most common agricultural pathogen in Hungary. The utilization of infected maize as an alternative biogas raw material may be an efficient and environmentally friendly disposal method. In this case, Fusarium-, and mycotoxin-content of the maize have to be analyzed as well as the impact of these factors’ on the biogas production process. Our experience was based on the raw material basis of a biogas plant. Different amount of Fusarium free and infected maize grits have been added to the regular raw material mixture. The detection of Fusarium fungi has been analyzed
in experimental digesters throughout the different stages of mesophilic digestion. In the biogas liquid end product the Fusarium was detected by breeding and by microscope. According to our results, the Fusarium sp. was not detectable in the liquid end product after 30 days. -
New methods of compost homogeneity determination in sewage sludge based compost prisms
49-52Views:157There is no effective method of homogeneity measurement of compost prism. The most frequently used technology is the examination of the particle distribution. This method needs a lot of time and large number of samples. The aim of our research is establishing different effective methods to determine the homogeneity of compost prisms. During our work, we examined the homogeneity of a prism made of sewage sludge and saw-dust mixture.
The measurements were based on the different properties of raw materials. According to this we examined the homogeneity by moisture content, heavy metal content and gas distribution measurements.
The most effective method is the measurement of gasconcentration. Although gas-concentration measurements it need special equipment it has more advantages than the other methods. The examination of gas-distribution compensates the problem of sampling because the measurement is direct. It provides the opportunity to estimate the amount of emitted toxic gases and to determine the maturity of the compost and the effectiveness of the degradation. -
Applicability of reflectance to determine compost maturity
31-35Views:123The utilisation of composts depends on their maturity and stability. A great part of the determination methods can be set in laboratory and needs complicated sample preparation. The aim of this paper was introduce an effective and fast method which based on the different reflectance of the different organic compounds.
During our research we examined the degradation process of compost prisms based on sewage sludge, wood-clipping and straw with temperature and reflectance measurements.
As a result, we came to the conclusion that the reflectance, measured at 645 nm or higher, is applicable to determine compost maturity if it is used with temperature measurements. -
Effects of cultivation methods on some soil biological parameters of a meadow chernozem soil (Vertisols)
61-66Views:78The effect of extended drought conditions on soil, the unfavourable cultivation technologies and the application of chemicals have been enhancing the processes of physical and biological soil degradation, so the fertility of soil is gradually declining.
The effects of two cultivation methods – traditional ploughing (TP) and conservation tillage (CT) – on the biological activity of a meadow
chernozem soil were examined in a long term experiment. Different parameters of the biological activity of soil were determined. These are
the numbers of total bacteria, microscopic fungi, aerobic cellulose decomposing bacteria, as well as the activities of some important soil
enzymes and CO2 production.
Conservation tillage seemed to be a more favourable cultivation method for the majority of microorganisms, the activities of urease and
dehydrogenase enzymes and CO2 production, compared to the traditional ploughing system. These parameters increased significantly,
especially in the upper layer of conservation tillage plots. Concerning the plant cultures, the majority of microbiological parameters were
higher in the soil of vetch (Vicia sativa L.) depending on the cultivation methods, so involving the pulses to the crop-rotation seems to be
very important in this soil type.
According to the ninth year’s results, the importance of conservation tillage as a means of protecting the soil biological activity in meadow
chernozem (Vertisols) can be established; it was proven by microbiological investigations. -
Botanical Survey of a Seminatural Saline Meadow
38-44Views:77We made a botanical survey of a seminatural meadow situated in the vicinity of Hajdúnánás-Tedej in Hungary, using traditional phytocenological methods. The habitat, based on its soil-, and botanical characteristics, can be classified into the category of saline meadows. One of the landscape ecological values of this area is its mosaic-like structure and, as a consequence, this habitat can be divided into six characteristic associations with blurry borderlines and characteristic overlaps. Because of its rare plant species and species richness this area can be considered to be a valuable „seed bank” and a „stepping stone” in the ecological network among the larger, intensively cultivated fields. The area can be evaluated as moderately recovered, the natural species are dominant, but there are few disturbance tolerant species. Except for the two saline associations, the high grass associations, which make up about two-thirds of the habitat, are cut once a year; therefore, the agricultural utilisation of the area and its prevention against weediness are being assured at the same time.
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The role and impact of N-Lock (N-stabilizer) to the utilization of N in the main arable crops
51-55Views:218The nitrogen stabilizer called N-Lock can be used primarily with solid and liquid urea, UAN and other liquid nitrogen, slurry and manure. In corn it can be applied incorporated before sowing or with row-cultivator or applied with postemergent timing in tank-mix. In postemergent timing need precipitation for long effect. In oil seed rape and autumn cereals the N-Lock should be applied with liquid nitrogen in tank mix late winter or early spring (February-March). The dose rate is 2.5 l/ha. N-Lock increases the yield of maize, winter oil seed rape, winter wheat and winter barley 5-20 %. The yield increasing can be given the thousand grain weight. In case of high doses of nitrogen it can be observed higher yield. The quality parameter also improved, especially the oil content of winter oil seed rape and protein and gluten contents of winter wheat. The use of N-Lock increases the nitrogen retention of soil and reduces nitrate leaching towards the groundwater and the greenhouse effect gas emissions into the atmosphere. The degradation of the applied nitrogen is slowing down and the plant can uptake more nitrogen in long period. The effect of N-Lock the nitrogen is located in the upper soil layer of 0-30 cm and increasing the ammonium nitrogen form. The product can be mixed with herbicide products in main arable crops.
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Microbiological and Chemical Characterization of Different Composts
106-111Views:71Composting of agricultural waste is considered particularly important from the point-of-view of environmental protection. Degradation of organic substance results in a significant reduction of waste volume.
The end product of the composting process, mature compost, can be used as soil coverage against excess loss of wastes, for mulching, for organic manure etc. The problem of composting has come into limelight in environmental studies and in agriculture.
The quality of the mature compost is determined by physical, chemical and biological parameters of the composting process which, in turn, depend on initial composition of the raw materials, the technology, e.g. regular mixing and moistening and on environmental factors. Quality is the key question in compost use.
We studied the composting process in compost windrows of different raw material composition. We measured temperature, humidity content, pH, organic substance content, nitrogen and carbon content.
We counted the number of bacteria, microscopic fungy, ammonifying and cellulose decomposing microorganisms. We directed the composting process with turning weekly (to provide oxygen) and watering (to provide humidity content 40-60%).
We set up windrows of 1 m3 volume from dry plant substances (cornstalk, pea straw, tomato stalk and crop, weeds) and cow manure not older than 1 week. The cow manure was used at ratios of 0%, 35%, 50%, 65% and 100%, respectively.
We measured changes in compost temperature relationship with outside temperature until they were almoust the same. Humidity was 40-60% in most cases.
At the beginning of the process, pH was slightly acidic-neutral; it later becomes neutral-slightly alkaline (pH: 6.93-8.02) as ammonia is liberated from proteins.
At the end of the process, pH decreased again, due to humification.
Organic substance content decreased as microorganisms mineralized them. Organic carbon content decreased gradually due to microorganisms used it as an energy.
Total nitrogen content increased until middle of july and decreased gradually until than.
The carbon/nitrogen rate were higher in the beginning, it decreased until july-august and increased by smaller degree until end of the process.
The number of bacteria was higher in the first three weeks and between june-september. The number of cellulose degrading bacteria was the highest in the first three month, the number of ammonifying bacteria was the highest from the end of may until sepember.
The number of microscopic fungy was significant in the second part of process, after july. -
Evaluation of chickpea (Cicer arietinum L.) in response to salinity stress
105-110Views:246Soil salinity is a severe and expanding soil degradation problem that affects 80 million ha of arable lands globally. Chickpea (Cicer arietinum L.) is very sensitive to saline conditions; the most susceptible genotypes may die in just 25 mM NaCl in hydroponics. Approximately 8–10% yield loss in chickpea production is estimated due to salinity stress. However, it is still not established why chickpea is so susceptible to salt affection. Salinity (NaCl) impedes germination of seeds, though chickpea varieties considerably differ from one another in this respect. Some chickpea genotypes are more tolerant in the stage of germination, tolerating even 320 mM NaCl. The reasons of this variation are unrevealed; there is a shortage of knowledge about the germination abilities of chickpea genotypes in saline conditions. Nevertheless, the effect of salt stress on vegetative growth can be analysed in hydroponics, in pot or field conditions, regardless the experimental environment, the ranking of genotypes regarding salt resistance is coherent. Chickpea genotypes can be different in their ability to retain water, maybe under salt affection; the more salt tolerant lines can maintain higher water content in the shoots, while the more sensitive ones cannot. The identification of salt tolerant chickpea landraces based on developing genetic variability is a suitable strategy to combat against salinity problems arising in arid and semi-arid areas.
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Heavy Metals in Agricultural Soils
85-89Views:72The soil constitutes the basis of the food chain. To keep soil conditions in a good trim is very important, it’s part of the sustainable development and of producing food supply harmless to health.
In some cases, soil productivity is the only important part, qualitative requirements or economical characteristics can improve it. The soil is threatened by two danger factors: the soil degradation and the soil pollution. The accumulation of different harmful and/or toxic substances in the soil is well known. Heavy metals constitute a part of it. Metals in the soil and in the soil-solution are balanced. This balance depends on the type of the metal, on the pH, on the cation-band capacity of the soil, on the redox relations and the concentration of cations in the soil.
To be able to handle the metal contamination of the soil, it is important to estimate the form, the possible extension and the concentration of metals.
Of course, the different types of soils have different physical-chemical, biological and buffer capacity, they can moderate or reinforce the harmful effects of heavy metals. To draw general conclusion of the dispersion and quantitative relations on the metals originated from different contamination sources is hard, because in some emissive sources contamination is limited in small areas but on a high level, some others usually expand on larger areas, and as a result of equal dispersion, the contamination’s level is lower.
Heavy metals – unlike alkali ions – strongly bond to organic materials, or infiltrate in a kelát form. Their outstanding characteristic is the tendency to create metal-complex forms. Kelats take part in the uptaking and transportation of heavy metals. Heavy metals exert their effects mostly as enzyme-activators.
The metals cannot degrade in an organic way, they accumulate in living organisms, and they can form toxic compounds through biochemical reactions.
Lot of the heavy metals accumulate on the boundaries of the abiotic systems (air/soil, water/sediment), when physical or chemical parameters change, and this influences their remobilization.
Human activity plays a great part in heavy metal mobilization, results in the human origin of most biochemical process of metals.
To understand the toxic influence of accumulated metals of high concentration, their transportation from soils to plants or their damage in human health, must clearly defined and investigated.
For effective protection against soil pollution, the types and levels of harmful pollution to soil must identified, regarding legal, technical and soil-science aspects, preferable in a single way. Difficulties in this area mean that toxicity depends on loading, uptake, soil characteristics and living organisms (species, age, condition etc.), furthermore, local and economic conditions considerably differ.