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The aim of our research was to determine the influence of the soil type and adjuvants on the dynamics of ethofumesate degradation in soil. Samples of two types of soil were placed in growth chambers. Ethofumesate was applied at a rate of 800 g·ha⁻¹, alone and in mixture with adjuvant based on methylated crop oil and surfactant adjuvant. Residues of ethofumesate were determined using high-performance liquid chromatography with UV detection. The type of soil influenced the degradation rate of ethofumesate. Significant differences in degradation rate between soils during the first period after treatment (36 days) influenced the DT₅₀ indicator. The addition of oil adjuvant slowed down the degradation of ethofumesate and increased the level of residue in soils. The DT₅₀ value for mixture ethofumesate + oil adjuvant was about 8-10 days higher in comparison with the DT₅₀ for ethofumesate applied alone. No significant differences were observed between degradation rates and the DT₅₀ for ethofumesate applied alone and with surfactant adjuvant.
The trial of explanation of the phenomenon of peat soil degradation was undertaken on the basic of literature and experiments carried out in cooperation between Polish and Belarussian institutes
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In the present paper, on the basis of altitude measurements, changes of topographic profiles of a chosen dried valley in Elizowkaon the arable land were presented. Intensity of water erosion was also studied on the unprotected loess terrain for 40 years.On the average, 22 cm of mud deposited on the tested section of the valley bottom (total area of 1.28 ha) along 500 m of the water race line, with the average width of 25.ʹ6 m. In consequence, the local erosion basis was raised and the average inclination decreased slightly. Physico-chemical properties did not significantly change within 40 years and these factors are typical of deluvial soils with unshaped profile. Their partial improvement points to reduction and stabilisation of erosion processes. That phenomenon is associated with slight thaw water run-off and the lack of larger storm precipitation.
In the study, the content of heavy metals such as Pb, Cd, Ni, Cu, Zn and Mn in the soils collected from various regions of the Lublin Voivodeship was examined. The examined soils were light medium soils. Content of individual elements was determined by the AAS method in the extracts of 1 M HCl. The analysed soils were poor in copper and manganese. Their concentration and the concentration of lead, cadmium and nickel was in the lower realms of the range natural for light soils formed from sands. Only the content of zinc was fairly high in the above soils, frequently as high as the first degree of contamination.
In the Slovak Republic, the moderate up to the extreme potential erosion risk was assessed for 65% of agricultural soil fund. We analyzed the universal erosion control principles, established legislative documents associated with soil erosion control, relationship between water erosion intensity and existence of soil, as well as computing methods, used in erosion control. The results of these analyses show that if the actual legislative acts will be applied in practice, soon or later the soil layer on specific sites will by totally devastated. We have also found out that application of STS No. 75 4501 protects soil better than application of Act No. 220/2004.
In the result of geomechanical transformations associated with the activity of open cast brown coal mining, some changes in air-water relations may occur on arable land adjacent to these regions usually referred to as hvdrological alterations. However, they do not always need to result in soil degradation, i.e. in the deterioration of their production potentials. This will often depend on the distance of fields from the workings, value of the arable land (soil quality class), type of water management, etc. On the basis of long-term studies carried out in the area of operation of two brown coal mines - KWB "Konin" and "Adamów" - on arable land and grasslands of over 60 villages on the total area of 30 thousand hectares it was possible to develop evaluation criteria for the extent of soil degradation and work out principles for compensation payments for farmers. Three zones and appropriate sub-zones of soil susceptibility to drainage were determined and clear and simple criteria for the estimation of the extent of arable land and grassland degradation were worked out. Furthermore, the authors proposed simple and readable systems to calculate compensatory payments to be paid to farmers taking into account the state of soil degradation, value of agricultural land (price of 1 ha of land of appropriate class) and the area of damaged land. The degree of soil degradation, both of arable land and grasslands, ranged from 10 to 30%. In the case of grasslands, additionally, an appropriate sum of money was allocated to compensate for sward recultivation.
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Simulation of temperature in peat muck soil

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Soil temperatures predicted with the use of temperature gradient method (GRA-GRO model) were compared with those measured at the experimental site. The experimental data are close to the theoretical values.Unfortunatelythe some differences exist. The lack of agreement between the simulated and measured data is sometimes disappointing (end of simulation), but indicates more that anything else the areas in which our knowledge is lacking.Present results indicates that the model can be used for predicting the change of temperature of soil but the further studies in both the field and model verification need to pay respect to infiltration of water into soil after rain and measuring of thermal conductivity of soil.
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