Search
Search Results
-
Assessment of Environmental Susceptibility/Vulnerability of Soils
62-74Views:84Soils 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. -
Complex assessment of inland water fish stocks
74-80Views:69In the domestic fish production, natural waters have yielded for several years about 7-8 thousand tons. This, from the point of view of outputs, considering the almost 130 thousand hectares of natural water, is rather low, it means approximately 55-60 kg/ha mixed fish.Although the various natural waters can differ significantly on the basis of yields, yet on the majority of the territories, the results were low. In the case of our extensive still waters and rivers, the reason can undoubtedly be found in the combined effect of the lack of the possibility of reproduction of the fish stock and the over-fishing. Fishery built on planning supposes the best possible knowledge in the given circum stances of the parameters of the water area and its fishstock. Lacking this knowledge, it is not possible to establish the optimal use fulness of the resources, what is more, the management can make faulty decisions – as a result of a lack of information -, which can risk the success of later activities.
It is known that many factors have an impact on the success of the fishery, as well as some information in connection with the water area and the fish stock are necessary, the knowledge of which make it possible to manage the fishery in a planned way. One part of the information is available, while the other part is incomplete or not deep enough. The necessary data are dissimilar depending on their nature, can be obtained from different places, by different methods.
As the first step for executing the field surveys and processing data, I developed a complex model, which contains in a unified system the steps of estimating the fishstock. I made the sampling on the basis of this. Part of the model is a fish faunistic survey, as well as a morphological survey of the water area. The information gained from these are important for making more accurate the system of devices of the samplings for stock estimation (duration, number of net-rows) and for assigning its place (places representing the best way the physical characteristics of the given water area). The major stages of stock-survey: A) faunistic survey, B) physical survey of the bed, and C) sampling with the help of gill-nets. This is followed by the evaluation by the computer module.
The results of the research create a methodological and technical background for the fish faunistic and population biologic surveys still performed in different ways in our country, and by applying these methods together, all basic information about natural waters which help decision-making concerning fisheries can be obtaine deffectively. -
The relationship between silver crucian carp (Carassius auratus gibelio bloch) and fish poulations of natural waters
30-36Views:89The fisheries management on inland waters is very complicated. Often the unclear propriety rights make the normal management difficult, and other times the stocking of the waters is problematic. In the last hundred years a lot of new fish species have been introduced to Hungary. Lot of them have found their place in the Hungarian fishfauna, till others have caused big problems for the fish farmers, and the anglers too. The biggest problem was caused by the topmouth gudgeon (Pseudorasbora parva Schlegel, 1842) brown bullhead (Ictalurus nebulosus LeSueur, 1819) and the silver crucian carp (Carassius auratus gibelio Bloch, 1782). In this article I show what kind of problems were caused by the silver crucian carp, because it seems that this fish is the most harmful.The damage caused by silver crucian carpposesa complex question. To get into the ponds and rivers, the crucian carps occupy the territory form the native fishspeciesandthesilvercrucian carp competes with these fishes for food, too.The silver crucian carphasa special reproduction method and because of this the speciesis expand rapidly. The silver crucian carp is able to reproduce with other cyprinids, and because the female silver crucian carps are triploids every fingerlings will be silver crucian carp.This fish is a vectorfora lot of diseases, which can easily spread over for other species.
-
The Effect of Changes in Forest Area on the Transcarpathian Tisza River Basin
181-185Views:66Forests are unique global factors which ensure life for almost every living being on Earth. They play a major role in controlling water flows, preventing erosion and controlling the oxygen content of Earth’s atmosphere. By the end of the XXth century, it was realized that forests help to nature maintain and are vital parts of our natural environment. By the time societies realized this fact, economic and environmental effects had amplified which endanger forests. Due to their good water control and water protection abilities, and their function in climate control, mountain forests can provide a suitable environment for themselves, for their successful growth.
Forests play a major role in soil protection, especially in mountain areas where they prevent soil erosion. By converting surface waters into subsurface waters, forests help with the accumulation of subsurface waters, which are the sources of springs, rivers and streams. In the summer, they protect the soil from drying out by creating a special microclimate. They positively affect the climate of surrounding territories. -
Optimizing fish structure in angling ponds focusing on white fish
33-36Views:166According to new amendments of laws, commercial fishing licenses of natural waters shall not be issued from the calendar year 2016 in Hungary. However, the most settlement of white fish to angler ponds originated from natural waters. Currently, there is no sufficient quantity of fish species belonging to this group available to fulfil the settlement commitments of fish farmers. The aim of this recent study is to develop a breeding and production technology that is suitable for settlement of large quantities of this fish species of appropriate length of (4–5 cm). The following methods are investigated: aquaculture cage system (pond-in-pond system), monoculture and mixed population with different ratio of white fish in fish structure. Due to the different environmental needs of different fish species, many parameters need to be investigated, for example: stocking density, feeding, oxygen level, monoculture or mixed populations, growth potential and mortality. A preliminary experiment was carried out following the artificial propagation of ide (Leuciscus idus) following a 21-day larval rearing experiment in which the effect of different stoking density was investigated for mortality and growth. On the basis of the expected results, the optimal conditions for the aquaculture cage system will be described, regarding to the white fish stock.
-
Influence of Hydrological Parameters on the Biodiversity of the BerettyóRiver I.
215-229Views:96The DIRECTIVE 2000/60/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL orders the measurement of the state of natural and artifical waters. We therefore applied environmental qualification methods, which allow inductions of the searched area in environmental management, conservation and water quality protection points of view. These methods are accepted in interdisciplinary sciences, and are in use in Hungarian and international practice. We applied the range data measured along the Berettyó River, and ratified by the remote sensing, to count hydrological-hydraulical attributes of the stream, by the framework of the Hec-Ras programme. We processed the physical, chemical and biochemical water qualifications, determined the MMCP-index (the point-system of the Hungarian macrozoobenthos taxons), and estimated the Spencer index-numbers, which were based on complex environmental qualification and bioindication. Appointed, that the different results of researches are not inconsistent. This results together the spatial analysis reveal the natural and anthroponetic specialities of the river and the landscape, which determine the environmental flavours and biodiversity. The bioindicators represent better environmental status, than the physical, chemical and biochemical parameters. The natural conservationist importance of drainage canal network of Bihari-Plain is appreciated by these facts.
-
Environmental Conditions of the Berettyóújfalu Sub-Region
403-413Views:64The purpose of this paper is to introduce the environmental conditions of the Berettyóújfalu sub-region, which is geographically located in Hajdú-Bihar County. I specifically target the regions’ relief, soil and hydrogeological conditions, climate, flora and fauna, natural value and present nature conservation activities.
On the basis of my investigation of these points, I can state that although this sub-region has unfavorable soil conditions, polluted surface and subsurface waters, it is rich in thermal waters, nature reservations and wildlife. It’s disadvantageous characteristics can or should be amended, while the advantageous ones should be utilized by considering the principles of sustainability. At the end of this paper, I will make recommendations in connection with the latter point. -
Plant protection praxis on Hévíz Nature Conservation Area (Lake Balaton District, Hungary)
81-83Views:141The nature conservation park, which belongs to the Spa and St. Andrew Hospital for Rheumatics of Hévíz, is 60 ha in size. The famous Lake of Hévíz, the two overfalls and the main buildings of the hospital are located in the middle of the park. They are surrounded by protective forests, parks and gravel esplanades. During the past few decades, the population of neophyton plants and invasive insects have increased considerably. These mean serious challanges to develop efficient control methods. Special care must be taken of environmental and plant protection regulations. Keeping plant protective regulations are especially strict around natural and spa waters.
-
Causes of floods and flood protection in Subcarpathia
72-75Views:90Subcarpathia is one of the richest regions in surface waters in the Ukraine. Due to its geographical, relief and climatic conditions, it belongs to the active precipitation zone, where great floods frequently occur. As a result of many years of observation, it can be concluded that the interactions of many natural factors can lead to various floods in the catchment area of the river Tisza. These are mostly hydro-meteorological factors, which can lead to great floods with the characteristics of the formed flow. Human activity also significantly influences the occurance of floods: clearing, which can accelerate the process of the runoff, ploughing in the catchment area, which can lead to erosion and the utilisation of areas endangered by floods for various economic sectors.
A series of questions arose in recent years regarding the formation of floods: what could be the causes of floods and what actions need to be made to prevent them. The evaluation of floods made us conclude that passive protection by using dams does not always ensure protection against floods as these were constructed in different times for different water levels. Many factors can affect the whole process which cannot be foreseen, therefore the development of new solutions and new technologies is necessary in flood protection. -
The effect of the supply chain exerting physical stress on the microbiological status of bottled natural mineral water
189-193Views:175Mineral water consumption increased dramatically in the last 30 years. One reason for this change lies in the changing consumer behaviour: consumers are increasingly recognizing the importance of healthy nutrition and appreciate the beneficial nutritional physiological properties of mineral water. Local mineral water harmonizes well with imported waters. Bottled mineral water may travel several hundred kilometres until it reaches consumers. In the present study, the dynamic mechanical vibration caused by transporting on public roads was simulated in laboratory vibration tests then samples were subjected to microbiological examinations in compliance with legislations currently in force. Due to this vibration, the initial microbe count increased by two orders of magnitude, while after terminating the 4-hour mechanical action it decreased gradually. Growing dynamics of microbes constituting the total germ count at 22 °C and 37 °C were almost similar.