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Szélerózió okozta talaj-, humusz- és tápanyag-áthalmozás különbségeinek feltárása különböző szerkezeti adottságú csernozjom talajokon terepi szélcsatorna kísérletek alapján
Exploring the differences in soil, humus and nutrient accumulation caused by wind erosion on chernozem soils with different structural properties by field wind tunnel experiments
Erosion On Surface Soil Texture And Characteristics Of Windblown Sediments . Journal of Geophysical Research-Biogeosciences . 2009. 114 . G02003 . Larney , F. J ., Bullock , M. S ., Janzen , H. H ., Ellert , B. H ., Olson , E. C. S . , 1998
The climatology of soil respiration in Hungary is presented. Soil respiration is estimated by a Thornthwaite-based biogeochemical model using soil hydrophysical data and climatological fields of precipitation and air temperature. Soil respiration fields are analyzed for different soil textures (sand, sandy loam, loam, clay loam and clay) and time periods (year, growing season and months). Strong linear relationships were found between soil respiration and the actual evapotranspiration for annual and growing season time periods. In winter months soil respiration is well correlated with air temperature, while in summer months there is a quite variable relationship with water balance components. The strength of linear relationship between soil respiration and climatic variables is much better for coarser than for finer soil texture.
Summary
During the research, we studied the soil conditions in Zala County's forests and examined the effect on the growth of beech forests on these conditions. Data of National Forest Data Base (NFDB) were analysed for investigation. Most of the forests in Zala County are situated less than 150 m above sea level, their location and topography is very diverse. In most of the forests the groundwater level is deeply beneath the surface so the forests can utilize only the amount of precipitation. In accordance with the geological and climatic conditions, Luvisols were formed predominantly, especially the clayic Luvisols and the gleyic Luvisols are the most typical. In addition, there are still Cambisols and stagnic Luvisols as well. In a small percentage, there are forest stands on rendzinic Leptosols, Vertisol, Regosol and Histosol. According to the favourable parent material, forests have got a deep or medium thickness of soil and the typical texture is loam. Based on the research, soil layer thickness and texture had significant impact on the growth of beech forest stands in terms of soil properties.
Basil (Ocimum basilicum L.) is one of the important aromatic plants belonging to the family Lamiaceae, which is used as an herb, spice as well as fresh vegetable.The present study was performed to determine the irrigation depth index under different management conditions with evaluating the effect of deficit irrigation, soil texture and nano fertilization on basil. The experiment was performed as a factorial based on randomized complete block design (RCBD) with 18 treatments and three replications at weather station, Ferdowsi University of Mashhad. Deficit irrigation treatments consisted of three levels of irrigation (I1=100% ETc), (I2=75% ETc), (I3=50%ETc) and three levels of nano fertilizers, containing nano fertilizer with full concentration (F1), 70% (F2), and nonusing of nano fertilizer (F3) were implemented in two light soil texture (S1) and medium soil texture (S2). The results showed that the average actual evapotranspiration estimation by REC-P55 device has been equal to 3.38 mm at the beginning of the growing period of basil, which amount has increased to 8.60 mm during basil development in the middle of growth period. The results of crop coefficient analysis showed that the maximum kc of basil (1.42) was detected in July. The results also indicated that the highest water use efficiency (WUE) was obtained in terms of fresh and dry herb yield as 2.06 and 0.37 kg/m3 in S2I3F3 treatment, respectively, while the maximum water use efficiency in terms of seed yield (0.37 kg/m3) was obtained in S1I2F2 treatment. Using the research results, according to different levels of water use of functions of yield Y(w), cost C(w), and benefit B(w) for basil based on mathematical and economic analysis of these functions, irrigation index and optimal irrigation depths were evaluated. It was found that with deficit irrigation under water restriction conditions, with the aim of maximum use of water volume unit, the optimal water consumption depth will be reduced by 20% compared to maximum irrigation mode. Also, with this amount of deficit irrigation, the maximum Rial return per cubic meter of water consumption would be as 1849 Rials.
Blending is widely used for modification of the physicochemical properties of fats to enhance their commercial applications. This paper studied the flow behavior of coconut oil (NHCO) under variation in the temperature and proportion of fully hydrogenated coconut oil (FHCO). The oscillatory results showed that there is a change in the linear viscoelastic region, storage (G') and loss (G'') moduli with increasing proportion of FHCO in NHCO. In rotational tests, the blends showed shearthinning behavior. The viscosity of oils and their blends were investigated at different temperatures. The Herschel-Bulkley model was fitted to flow curves (shear stress in function of shear rate) of the samples. During heating, NHCO approached Newtonian behavior earlier than FHCO, because of their loosely-packed structure. Thus it indicated that the fatty acid composition affects these behaviors of the oil. The blending of fully hydrogenated coconut fat improved the elastic and textural character of the coconut oil.
Soil texture is an important input parameter for many soil hydraulic pedotransfer functions (PTFs) of the day. Common soil particle-size classes are required to be able to uniformly determine the texture of soils. However, it is not always possible - due to different national classification systems - and much valuable information is disregarded while either deriving or applying PTFs. One way to get common particle-size class information is to interpolate the particle-size distribution (PSD) curve. Advanced interpolation solutions are becoming available, but there is always uncertainty associated with these techniques. Another possibility is to measure all PSD curves in such a way that it is compatible to the commonly used classification systems. A new automated measurement technique is introduced that can easily provide PSD data compatible to any (and all) of the existing national and international classification systems at the same time, without the burden of extra labour. A computerized measurement system has been developed to record density changes in a settling-tube system in any discretional (small) time steps, which in turn allows the derivation of a quasi-continuous PSD curve. The measurement is based on areometry (Stokes-law), thus the system is compatible to the most commonly applied settling-tube measurements. The new evaluation method of measured values takes into consideration the density changes along the areometer-body so it avoids the problem of reference point determination. The theory and setup of the system are explained and measurement examples are given. The presented comparative measurements show good correspondence with conventional settling-tube results, and the reproducibility of the measurement shows to be very high. This technique does not require more sample preparation than past methods. The automated reading requires less manpower to perform the measurement - which also reduces human error sources. However, it provides very detailed PSD data that has advantages, like revealing multi-modality in the particle-size distribution or providing data that complies with any of the classification systems.
The aim of the study was to determine K-factors of homogeneous zones in palm-groves in order to make possible the interpolation of these values to other similar areas, and by this way to help the calculation of draining parameters. Another goal was to interpret the agronomical aspects of the results. Investigations for the determination of conductivity factors (K-factors) were carried out in the palm-groves of the Oued Rhir Valley. The measurements - conducted three times - were made by the auger-hole method. After boring the hole, a perforated cylinder was placed into it to prevent falling in. K-factor values were calculated after van Beers. The mean of the three calculations was given as the end result for the K-factors. Our results show that K-factor values are influenced by the porosity, type, bulk density and texture of soils, their salt content and the form of gypsum. The K-factor was extremely high in case of sandy soils and soils containing crystallized gypsum. Water conductivity was moderate in case gley and pseudogley were located in deeper layers. The lowest values occurred when gypsum was found in cemented coherent particles. Salinization in deeper layers influenced hydraulic conductivity only in case it was associated with finer texture and airless layers. Besides date production, the traditional growing of nitrogen-fixing perennial legumes (alfalfa, Egyptian clover, melilot, etc.) in palm-groves is essential. Systemic flooding irrigation decreases the salt content of soils, increases date and legumes yields. Legumes - by their root-system - improve the nitrogen balance, structure and water drainage of soils. The green parts of the cultivated legumes serve as fodder for animals (goats, sheep, cows), which turn it to manure. This manure increases the nutrient supply of the soils for palm-trees and vegetables. The positive results of stubble and root manuring (green manuring) of legumes is also confirmed by experiments on sandy soils. The elaboration of a good plant rotation is possible. At last, date and vegetables produced in this way could be sold better on the world market as bioproducts.
In our research marzipan samples of different sugar to almond paste ratios (1:1, 2:1, 3:1) were stored at 17 °C. Reducing sugar content was measured by analytical method, texture analysis was done by penetrometry, electric characteristics were measured by conductometry and hyperspectral images were taken 6–8 times during the 16 days of storage. For statistical analyses (discriminant analysis, principal component analysis) SPSS program was used.
According to our findings with the hyperspectral analysis technique, it is possible to identify how long the samples were stored (after production), and to which class (ratio of sugar to almond) the sample belonged. The main wavelengths which gave the best discrimination results among the days of storage were between 960 and 1100 nm. The type of the marzipan was easy to distinguish with the hyperspectral data; the biggest differences were observed at 1200 and 1400 nm, which are connected to the first overtone of C-H bound, therefore correlate with the oil content. The spatial distribution of penetrometric, electric and spectral properties were also characteristic to fructose content.
The fructose content of marzipan is difficult to measure by usual optical ways (polarimetry, spectroscopy), but since fructose is hygroscopic, the spatial distribution of spectral properties can be characteristic.
Munkánk során különböző klímaváltozási forgatókönyvek lehetséges hatását értékeltük a hazai mészlepedékes csernozjom talajok vízmérlegére. Igazoltuk, hogy a vizsgált talajok vízforgalmát alapvetően meghatározzák az időjárási feltételek. Megállapítottuk, hogy a talaj víztartóképesség-függvényének jellemzésére használt arányossági együttható esetenként megfelelő indikátora lehet a talajvízforgalom klímaérzékenységének. A szélsőséges csapadékösszegű években nagyobb eltérést tapasztaltunk a különböző klímaforgatókönyvekre becsült talajvízmérleg elemek között, mint az átlagos csapadékmennyiséggel rendelkező években. Ezt az általános tendenciát azonban az A2 szcenárióra jellemző, nagy csapadékintenzitással bíró extrém időjárási helyzetek esetenként felülírták, elsősorban a mélybeszivárgás megnövekedése révén. Ez felhívja a figyelmet arra, hogy bár modellezési eredményeinkből kimutathatóak általános összefüggések, a talajok klímaérzékenységének tanulmányozásához szükséges a csapadék éven belüli eloszlásának és a szélsőséges időjárási helyzetek hatásának vizsgálata is. Eredményeink arra engednek következtetni, hogy az azonos mechanikai összetételű, de eltérő szerkezetű talajok vízforgalma megváltozott klímafeltételek között is jelentősen eltér, tehát megfelelően megválasztott, talajszerkezet-megóvó és nedvességőrző talajművelési rendszerekkel elősegíthetjük a párolgási veszteségek csökkentését és a növényi vízfogyasztás növekedését. A kapott eredmények összevetése során kimutattuk, hogy statikus jellemzőkből, a talajvízforgalom folyamatának mérleg-elvekre épülő, dinamikus megközelítése nélkül csak óvatos következtetéseket vonhatunk le a talajok vízgazdálkodására és klímaérzékenységére vonatkozóan. Reményeink szerint a felvázolt összefüggések hozzájárulnak a megelőző, illetve a káros hatásokat csökkentő beavatkozási stratégiák kidolgozásához a szélsőséges vízforgalmi helyzetek negatív következményeinek enyhítése céljából.
In the hydrogeologically closed Carpathian Basin subsurface waters have particular importance in the salinization/alkalization processes. In the poorly-drained low-lying areas the capillary flow transports high amounts of water soluble salts from the shallow, „stagnant” groundwater with high salt concentration and unfavourable sodium-carbonate(bicarbonate) type ion composition to the overlying soil horizons. Due to the strongly alkaline soil solution, the Ca and Mg salts (mostly carbonates and bicarbonates) are not soluble and Na + became absolutely predominant in the migrating soil solution which leads to high ESP even at relatively low salt concentration. High Na + saturation of heavy-textured soils with high amount of expanding clay minerals results in unfavourable physical-hydrophysical properties and extreme moisture regime of these soils, which are their main ecological constrains and the limiting factors of their fertility, productivity and agricultural utility. The simultaneous hazard of waterlogging or overmoistening, and drought sensitivity in extensive lowland areas, sometimes in the same places within a short period, necessitates a precise, “double function” soil moisture control against their harmful ecological/economical/social consequences. Most of the environmental constrains (including salinity/alkalinity/sodicity) can be efficiently controlled: prevented, eliminated, or - at least - moderated. But this needs permanent care and proper actions: adequate soil and water conservation practices based on a comprehensive soil/land degradation assessment. It includes continuous registration of facts and changes (monitoring); exact and quantitative knowledge on the existing soil processes, their influencing factors and mechanisms.
