Tibor Filep

Dissolved organic carbon (doc) and dissolved organic nitrogen (don) content of an arenosol as affected by liming in a pot experiment

The effect of liming materials was investigated on the dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) content of the soil in a pot experiment on an acidic soil using oat (Avena sativa L. ) as an indicator plant. Soil samples were taken three times during the growing season. The lime rates applied were 0, 1, 2, 3 g calcite/pot and 0.92, 1.84, 2.76 g dolomite/pot, respectively. Due to an increase in soil pH and microbial activity the DOC concentration significantly increased with increasing lime doses at all three samplings. An exponential relationship was found between soil pH and DOC concentration: y v = v 0.3733e 0.7893x , r v = v 0.903***. Lime had a significant effect on DON concentration at the first sampling, while for the remainder of the growing period no further significant increases were found. This could be explained by the fact that the biodegradability of DOC and DON differs under conditions of the experiment, resulting in a decrease in the N content of the dissolved organic matter, while the amount of DOM and DOC increased with increasing pH. Because of the above mentioned facts the DOC/DON ratio increased significantly with liming. There were no significant changes in the dissolved organic carbon content of the soil during the 15-week growing period, while DON concentration decreased significantly. It can be explained by the initial addition of N fertilizer, which increased the DON quantity at the first sampling in the soil.

Spatial variability of hydrophysical properties of fallow sandy soils

Abstract Spatial heterogeneity of soil hydrophysical properties was estimated in 2 fallow sandy soils at Csólyospálos and Örbottyán, Hungary. Significant differences in small particle (= silt + clay) content (5.0% vs. 13.7%), organic matter content (1.62% vs. 0.91%), and CaCO3 content (3.1% vs. 5.1%) measured at Csólyospálos and Örbottyán, respectively, resulted in a higher persistence of water repellency in the Csólyospálos soil. It also resulted in a significantly higher water sorptivity and hydraulic conductivity of the Örbottyán soil. The spatial heterogeneity of soil hydrophysical properties was significant reaching 3 orders of magnitude differences due to the variances of soil properties. The water repellency cessation time was inversely related to the hydraulic conductivity and water sorptivity at Csólyospálos site.

Effect of Application of Nitrogen and Different Nitrogen–Sulfur Ratios on the Quality and Quantity of Mustard Seed

A greenhouse experiment was conducted on a calcareous chernozem soil to investigate the effects of nitrogen (N) and sulfur (S) fertilization and their ratios on the yield and quality of white mustard (Sinapis alba L.). Four levels of N [0.5, 1, 1.5, and 2 g pot−1 N as ammonium nitrate (NH4NO3) and ammonium phosphate (NH4H2PO4)] in combination with three levels of applied N–S ratios [8, 4, 2; S as potassium sulfate (K2SO4) and sodium sulphate (Na2SO4)] were tested as treatments. Results indicated that a significant response to seed yield was observed for N and S application. Maximum yield, 24.8 g pot−1, was found when full doses of N and S were applied. Increasing N supply from 0.5 g pot−1 to 1 g pot−1 had little increasing effect in the oil content of the seed. Higher application of N doses (>1 g pot−1) decreased these values significantly. The maximum oil content (28%) was achieved with the 1 g N pot−1 treatment; the lowest values were observed in the pots applied with the highest N doses. Changes in the N content of the seed and straw showed a statistically significant increase with increasing N and S fertilization. Highest values in the seed and straw (5.96% and 0.87%, respectively) were observed by applying highest N and S doses. Seed and straw S levels were also observed to increase with increasing N rates and decreasing N–S ratio. Nitrogen doses significantly improved the quantities of essential amino acids with the exception of threonine, tyrosine, phenylalanine, and methionine. The amounts of these amino acids decreased with increasing N supply. When the N–S ratio decreased by increasing S, the quantities of valine, isoleucine, leucine, lysine, methionine, and cysteine increased significantly and the amount of tyrosine decreased. The quantities of nonessential amino acids with the exception of proline, histidine, and glycine increased with increasing N doses. In contrast, N rates decreased the amount of glycine. Decreasing the N–S ratio lowered the proline and arginine contents. The total amounts of essential amino acids slightly increased with increasing N rates and decreasing N–S ratio.

Cadmium and chromium fractions on different soils as affected by communal sewage sludge loads

A pot experiment was set up in 1999 for examining the effect of sewage sludge loads on soils and plants. Four soils were used. Soils can be classified as the following: Őrbottyán, calcareous sandy soil; Nagyhörcsök, calcareous silty soil; Gyöngyös, acidic silty soil; and Nyírlugos, acidic sandy soil. Applied sewage sludge loads were 0, 2.5, 5, 10, and 20 g sludge DM/kg air‐dry soil. From the soil samples, total recoverable [cc. nitric acid (HNO3) + hydrogen peroxide (H2O2) digestion], extractable [0.5 M ammonium acetate + 0.02 M ethylenediaminetetraacetic acid (EDTA)–extractable], and the mobile [1 M ammonium nitrate (NH4NO3)–extractable] elemental concentrations were measured. There was an increase in all of three fractions after sewage sludge application for both cadmium (Cd) and chromium (Cr); the extent of changes was varied. To quantify the Cd and Cr response to sewage sludge loads, sewage sludge loads vs. elemental concentration functions were plotted, and the slope of these functions means sensitivity of soils in the given fraction. After examining the sensitivity of four soils in the three fractions for elements investigated, it can be stated that the most sensitive fraction was the total recoverable fraction. The ammonium acetate + EDTA–extractable fraction has the second greatest sensitivity, whereas NH4NO3 extraction was a good indicator for treatments only on sandy soils. However, the strongest correlation was found between mobile Cd and Cr and the plant element uptake. So there is an obvious contradiction: the fraction that is less sensitive to sewage sludge treatments has the strongest correlation with plant uptake.

Vörösiszappal szennyezett talajok kémhatása és sav-bázis pufferoló képessége barnaszéntartalmú talajjavító anyag alkalmazását követően

A 2010-es Ajkai vorosiszap-katasztrofa hatasainak csokkentesere tobb tudomanyos vizsgalat indult, beleertve azokat is, amelyekben kulonfele adalekanyagokkal probaltak megszuntetni a szennyezett tal...

Effect of soil pollution on alfalfa yield and element composition.

Rural economy in Croatia with your small sized sector of peasant enterprises still stays in the shadow of restructuring of large industrial sector. The slow leading process of privatization, the wandering in the claim the best solution in agricultural development, absence of consensus about key development priorities, as well as common indicators of backwardness, are only part of gray scale of problems which dented the continue pauperization of wide rural area in Croatia. The Croatian government administration late with implementation of new rural policy measures, which are recommended by Council Regulation (EC) No 1257/1999. This act emphasis the balanced development of the countryside alongside the market support measures in the lights of the social and territorial cohesion. It is based on the following principles: recognising the multifunctional role of agriculture, improving competitiveness, ensuring that environmental issues are taken into account, diversifying economic activity, and conserving rural heritage. In the past time new rural policy in Croatia is considered below local and regional development programs, where the LEADER approach take important role. This is result of pre-accession process to EU and new possibilities of using considerable financial support in IPA subsidy program 2007- 2113.