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Development opportunities of biomass-based ethanol production in relation to starch- and cellulosebased bioethanol production
71-75Views:112The biomass is such a row material that is available in large quantities and it can be utilizied by the biotechnology in the future. Nowadays the technology which can process ligno cellulose and break down into fermentable sugars is being researched. One possible field of use of biomass is the liquid fuel production such as ethanol production. Based on the literary life cycle analysis, I compared the starch-based (first generation) to cellulose-based (second generation) bioethanol production in my study considering into account various environmental factors (land use, raw material production, energy balance). After my examination I came to the conclusion that the use of bioethanol, independent of its production technology, is favorable from environmental point of view but the application of second generation bioethanol has greater environmentally benefits.
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Assessment of Environmental Susceptibility/Vulnerability of Soils
62-74Views:86Soils 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. -
Nutrient Uptake of Miscanthus in vitro Cultures
23-24Views:72The large biomass production and the low necessary input fertilizer make Miscanthus an interesting, potential non-food crop with broad applications, e.g. for fuel and energy, for thatching, fiber production, for the paper and car industries, as well as for ethanol production.
Axillary buds of Miscanthus x giganteus were placed on a shoot inducing nutrient solution (modified Murashige and Skoog, 1962), basic medium supplemented with 0,3 mg l-1 6-Benzylaminopurin. After 40 days of culturing, the axillary buds produced three times more shoots than could normally be harvested. The nutrient content (N, P, K, Ca, Mg) was measured several times during culturing. The results showed that, after 35 days, nitrogen and phosphate were nearly completely taken up. From that time, shoot growth was not observed.
After shoot propagation, the plants were transfered into a nutrient solution for root formation (modified Murashige and Skoog, 1962), basic medium supplemented with 0,5 mg l-1 Indole- 3-Butyric acid, and could be potted in soil after about 14 days. -
Potential use of bamboo in the phytoremediation in of heavy metals: A review
91-97Views:259There are many literature sources focusing on the phytoremediation of woody plants, but there are only few dealing with the phytoremediation of bamboo plants. Phytoremediation technology has the advantages of little disturbance to the environment and low remediation cost. Bamboo mainly exists in tropical and subtropical regions. As an energy plant, bamboo has a fast growth cycle, large biomass, simple cultivation, high economic efficiency, and convenient harvesting, which highlights the advantages of bamboo in phytoremediation. In addition, bamboo plants have good tolerance and uptake ability to heavy metals and have high application potential and development value in uptaking heavy metal contaminated soil. However, due to climate, temperature and other reasons, bamboo cannot be widely planted in most countries. Research status of remediation of heavy metal contaminated soil by bamboo plants is summarized. The feasibility of its application in heavy metal contaminated soil is discussed in this paper. Aiming at the shortcomings of existing research, bamboo plants have a prospect in the field of plant phytoremediation for the future.