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Heavy Metals in Agricultural Soils
85-89Views:77The 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. -
Characteristics of Land Use and Plant Production in Transcarpathia
290-294Views:44The character of plant cultivation and animal husbandry in different parts of Transcarpathia, are mostly determined by the location of a given region. Usually, four zones are delineated: 1. lowlands; 2. foothills and volcanic remains zone; 3. inter-mountainous subsidence and deep valley; 4. mountain zone.
In county this zone divides quite visibly. By studying the soil, climatic conditions and plants, it is not difficult to see that the vertical zones play a major role in their characteristics and formations. If we go from lower to higher elevations, we can observe the qualitative difference in the environment and, of course, in the character of agriculture.
Environmental pollution is a global problem of our age. In agriculture, the most important thing is to preserve the ideas of sustainable development, because only these can ensure the protection of production resources, which will ensure the continuous production of agricultural products. Present environmental conditions pose a more problematic challenge to agriculture. -
Ecological Conditions of Agricultural Land Use in Transcarpathia
190-194Views:80The unbalanced anthropogenic effects for several decades resulted in significant technogen damages in the ecosystem of Ukraine. Excessive land development, including the use of slopes, effected the disintegration of the natural balance of lands – arable-lands, meadows, forests, and watershed areas – producing quite a negative effect on the landscape’s nature itself. It has to be stressed that according to other indexes, too, agricultural lands show a tendentious deterioration.
Erosion, caused by water and wind, is one of the most influential factors in the degradation of agricultural soils and in the reduction of the productiveness of benefital lands. Nowadays the degree erosion became significant and it directly endangers the existence of the soil which is a principal chain-link of the agricultural cultivation as well as an irreplaceable element of the biosphere.
The social and political changes in Ukraine’s life demand fundamental modernization in the land utilization both in ecological and in economical aspects. However, these aims can be realized only if, during the developments, we base on the up-to-date results of agronomics, and we do further research in the relations of agricultural land use and environmental protection. According to the latest theories, rational and environmental-safe agricultural production relates to the optimum correlation of the natural- and agricultural- ecosystems as well as to the reconstruction of agricultural areas built on the basis of environmental protection.