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properties on the spatial variability of soil water content: evidence from sensor network data and inverse modeling Vadose Zone Journal . 13 . ( 12 ) 112 . doi: 10.2136/vzj2014.07.0099 Q u

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. BÁRDOSSY, GY. , 2006 . Geologic and geostatistical evaluation of spatial variability . Acta Geologica Hungarica . 49 . 89 – 101 . B OURENNANE

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A talaj elektromos vezetőképessége és a termőhelyi zónák talajtulajdonságai közötti összefüggések

Correlations between soil conductivity and soil properties of crop management zones

Agrokémia és Talajtan
Authors: Kocsis Mihály, Menyhárt László, Benő András És, and hermann Tamás

. http://ikr.hu/tudastar_gabonaterm_ml.php Melchiori , P. Z . , 2002 . Spatial Variability Of Wheat Yield, Association With Edaphic Parameters And Assessment Of Application Of Nitrogen For Specific Sites. Thesis For Master Of Science Degree . National

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ecology . 23 . ( 12 ) 2988 – 2999 . 10.1111/mec.12786 Qiu , Y ., Fu , B ., Wang , J ., & Chen , L . , 2001 . Spatial variability of soil moisture content and its relation to environmental indices in a semi-arid gully catchment of the Loess

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Csillag, F., Kertész, M. & Kummert, Á. , 1996. Sampling and mapping of heterogeneous surfaces: multi-resolution tiling adjusted to spatial variability. International Journal of Geographical Information Science. 10 .(7) 851

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Our data verified the relationship between meteorological factors and the fluctuation of the groundwater level. The rate of evaporation dominantly affected the rise and depth of the groundwater level. It is characteristic for the study site that there is an inverse relationship between the elevation of the groundwater observation wells and the depth of groundwater, and the difference between the levels of groundwater in the separate wells reflected the differences in the elevation between the wells. Our observations refuted our previous assumptions, as in the wells not only the concentration of salts changed but also the chemical type of the water. This can be attributed with great probability to the lateral flow of the groundwater, which is caused by the vertical fluctuation, but can be caused by other geological factors as well. We reached the conclusion that the vertical and sometimes lateral movement of the groundwater affects the development of soils in a given area. It means that the reason behind the mosaic-like appearance of the soil cover of a given area can be searched in the local differences of the chemical composition of the groundwater, which is a major factor of the spatial variability of the salt accumulation of soils. The observations and analytical results point to that the soils of the study site have developed under the effect of fluctuating groundwater and the elevation is a dominant factor of the spatial variability of the soil salt accumulation. The level of groundwater, the flow of groundwater and its composition show relationship with the surface elevation, and their effect is modified by the geological stratification, which results in a variable appearance of soil salt accumulation and native vegetation.

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A talaj N-szolgáltató képessége és az elérhető termés – többek között – függ a 0,01 M CaCl2-oldható szerves N-frakció mennyiségétől. Jelen tanulmányban vizsgáltuk, hogy a növényi kondíció és a termés hogyan változik a táblán belül egy heterogén növényállományban, és milyen összefüggésben van a 0,01 M CaCl2-oldható szerves N-frakció mennyiségével. Egy 10,4 hektáros mintaterületről növénymagasság térképet készítettünk, majd a különböző magasságú állományrészekben több ismétlésben mintavételi pontokat jelöltünk ki. Mintavételi pontonként termés- és talajmintákat vettünk. A mérési eredmények alapján megállapítottuk, hogy a termés, a levelek SPAD-értéke és a talajban lévő 0,01 M CaCl2-oldható szerves N-frakció mennyisége a növénymagasság növekedésével nőtt, míg a termésben jelentkező heterogenitás csökkent. Megállapítottuk, hogy a növényállomány heterogenitásában szerepet játszhat a 0,01 M CaCl2-oldható szerves N-frakció mennyiségének területi variabilitása is. A termés becsülhető a 0,01 M CaCl2-oldható szerves N-frakció mennyisége és a termés közötti összefüggést kifejező regressziós egyenletek alapján, viszont a becslés pontossága a különböző kondíciójú állományrészekben eltérő.

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. Proc. 39. 755–763. Farkas , Cs . & Rajkai , K., 2002.Moisture regime with respect to spatial variability of soil hydraulic properties. Agrokémia és Talajtan. 51. 7

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Agrokémia és Talajtan
Authors: Barbara Simon, E. Michéli, G. E. van Scoyoc, and et al.

The Typic Haplustalfs soils (Karád and Oltárc) and the Typic Ustochrepts (Gödöllő) are developed on loess, and on aeolian sand parent material, under forest vegetation, resp. The Dystric Ustochrepts (Velem) soil formed on metamorphic schist parent material and had forest vegetation, while the Typic Medisaprists (Zalavár) soil developed on peat parent material and had marsh vegetation.   Based on this study the spatial variability of surface pH samples indicate that the TIM sampling procedure should be improved. Ten to thirty samples must be collected at each site to be able to monitor changes of 0.2 pH units. If only one sample is taken at each site yearly, spatial difference in pH or other parameters are likely to obscure differences which may be occurring over time.  The colloidal composition (organic matter and clay minerals), influenced by parent material, vegetation, and precipitation, showed a close relationship with the acidity factors, such as pH, HAC 1 and EAC 1 values. The pH values were the lowest in the Velem and Oltárc soils where the annual precipitation was the highest (750-800 mm), and in the Karád soil, where the annual precipitation was 650-700 mm. The Gödöllő soil had the highest pH values, probably due to the lowest amount of rainfall (550-600 mm) and the disturbance. The Zalavár soil had fairly high pH throughout the profile probably due to a fluctuating water table.   The HAC 1 and EAC 1 values were the highest in the Velem soil when compared to the other mineral soils.  The pH values were the lowest at this site. The HAC 1 and EAC 1 values were lower in the other three forest soils, at the Karád, Oltárc, and Gödöllő sites. The Zalavár soil had fairly high HAC 1 values in the H3, H4 and H5 horizons, probably due to the very high OM content, which provided a lot of H + ions that can dissociate from the exchange sites.   The E4/E6 ratios were closely related to the decomposition or humification rate in the upper and the subsurface horizons with accumulation of low molecular weight soluble fraction in the deeper horizon.   The mineralogical analysis showed similar compositions for the soils developed on loess (Karád and Oltárc), or aeolian sand (Gödöllő), where the major minerals were vermiculite, mica, kaolinite, and chlorite. A different mineral composition (mica, vermiculite, clintonite, and kaolinite) was observed for the Velem site, where the parent material was metamorphic schist. The four mineral soils are forest soils, with a predominant downward water movement, thus with fairly intensive leaching process. However, there was a distinct difference among the soils formed on loess (Karád and Oltárc), or aeolian sand (Gödöllő), and the soil (Velem) developed on metamorphic schist parent material.  The soils at the Karád, Oltárc, and the Gödöllő sites were less acidified, with higher pH, and lower HAC 1 , and EAC 1 values as compared to the Velem soil, even if the precipitation was very high. The calcareous loess parent material probably compensated for the higher precipitation and the resulting leaching process at the Karád and the Oltárc sites. The Gödöllő soil received a very low amount of precipitation, which resulted in a low degree of weathering, with higher pH, and lower HAC 1 , and EAC 1 values. However, the metamorphic schist parent material probably contributed to a lower pH and lower buffering of the developing soil.   Based on the chemical and physical analyses, we concluded that among the soil forming factors, precipitation and parent material had the greatest influence on the acidity characteristics of the examined soils. The parent material influenced the mineralogy of the developing soil, which then influenced the pH, HAC 1 , EAC 1 , and CEC values of the soil. In order to substantiate these tendencies more samples from a wider array of geological regions are needed.   

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