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Assessment of Environmental Susceptibility/Vulnerability of Soils
62-74Views:247Soils 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. -
Reduction possibilities of the production costs of green electricity by using waste heat
15-20Views:284In my study, I examine the possibility of the reduction of green electric power’s gross production cost. My research topic may have wider considerations, since in the case of CHP technology the utilization of by-product thermal energy is not possible, and the whole production cost devolves upon green electric power. I introduce five options for the use of the heat energy, based on national and international literature and in-depth interviews.
From the aspect of efficiency, it can be stated that as alternatives, beer production and desiccation may be mentioned, since these two models were appropriate for the utilization of the total quantity of waste heat, and in the given circumstances the lowest reduction of green electric power’s production costs was achieved in these cases utmost.
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Economic questions of maize production on different soil types
289-292Views:264The requirements and objective of cultivation are in constant change. For example, different cultivation systems are developed for the purpose of soil protection, the preservation of its moisture content and on soils with various precipitation supply or production site conditions. Traditionally, one of the most important cultivation aims is crop needs. Further cost saving in fertilisation and crop protection can only be achieved by reducing the quality and quantity of production or it cannot be achieved at all. Furthermore, the costs can be significantly reduced by means of the rationalisation of cultivation. Energy and working time demand can also be notably reduced if ploughing is left out from the conventional tillage method. The key requirement of economicalness is to perform the cultivation at the optimal date, moisture level and the lowest possible cost.
Within production costs, the cost of cultivation is between 3–17%, while they are between 8–36% within machinery costs. It is the vital condition the usability of each technological method to progressively reduce costs. Our evaluation work was carried out with the consideration of the yield data obtained from cooperating farms and the experiment database of the Institute for Land Utilisation, Regional Development and Technology of the Centre for Agricultural and Applied Economic Sciences of the University of Debrecen. Three technological methods (ploughing, heavy cultivator and loosening tillage) were used on several soil types which differ from in terms of cultivability (chernozem, sandy and sandy clay soils) from the economic/economical aspect. We examined the sectoral cost/income relation of maize production as an indicator plant. The maize price during the analytical period was 45 thousand HUF per t. On chernozem soils, the production of maize can be carried out on high income level, while maize production on sandy soils has a huge risk factor. The role of cultivation is the highest on high plasicity soils, since they have a huge energy
demand and the there is a short amount of time available for each procedure in most cases. -
Microbiological and Chemical Characterization of Different Composts
106-111Views:160Composting 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. -
Opportunities for improving the nutritional value of cereal-based products
275-278Views:905We set up experiments for improving the nutritional value of cerealbased products. Our aims were to decrease the energy content of bakery products with the mixing of plant originated raw materials and byproducts with high fibre contents, and we have evaluated the effect of sodium-chloride on the physical properties of bakery products. We found that the apple pomace, the byproduct of juice production, is excellent for increasing of fibre content of bakery products and the further aim of investigation is to develop economical ways of hygienic byproduct handling and purification. Our experiments, evaluate the bakery use of triticale, have significant achievements and the breads made from triticale flour and whole-grain are commercially available nowadays. Our investigations included the possibilities of decrease of toxin contamination of cereals and our results can form a part of risk estimation systems after further experiments .
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Texture analysis as a method for grape berry characterization
Views:613The marketability of table grapes is mainly characterized by berry size, color, taste and texture. Mechanical measurements of table grape berries could provide objective information on the textural qualities of grape berries. In addition, this method might be suitable to study the effects of phytotechnical methods (such as girdling) on table grape quality. The aim of this preliminary work was to demonstrate how instrumental testing could be used to examine the effects of girdling on berry grape texture and define the textural characteristics of table grape berries. Cane girdling was carried out at veraison in two table grape varieties. Texture analysis was performed several times during the maturity. Besides this examination another five varieties were analyzed to assess their berry mechanical properties. Double compression test was used to determine berry hardness and its derived parameters. Puncture test was applied to evaluate skin hardness, skin elasticity and skin break energy. Skin thickness was also investigated. Berry hardness, skin hardness and skin thickness of the girdled grapevines were significantly affected by this technique. Most of the textural parameters showed differences among the seven cultivars.
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Alternatives of sewage sludge use in the crop production
83-87Views:194The produced plants reduce the greenhouse effect because they fix CO2 that contributes to the causing of the greenhouse effect with about 50%. The production of fertilizers is not only a costly process but it needs a considerable energy at the same time. Nowadays, the reduction of the proportion of the fertilizer is significant. One of the reasons of this is that during the production such by-products are produced in a big quantity in which the necessary vegetal nutrients can be found in a considerable measure these enrich the organic matter of soil. The latter is essential condition for the microorganisms in the soil, without which the sustainable plant cultivation can not be achieved. Besides high prices of artificial fertilizers the utilization of the wastes is economically justified. Finally the other reason for the reduction of a usage of artificial fertilizer is that the wrong use of the fertilizer may cause environmental pollutions. I examined the cultivation application of the sewage sludge in laboratory circumstances during my work.