Péter László

The effect of conservation tillage systems on sustainability of soil biological state of sandy loam soil in corn monoculture

Introduction Conservation tillage, which involves the maintenance of crop residues on the soil surface, enhances soil conservation (Buchele et al., 1955) and controls soil erosion effectively (Romkens et al., 1973). Conservation tillage is an “umbrella” term encompassing several tillage systems including no tillage and ridge tillage (Mannering et al., 1983). Ridge tillage is a row-crop production system with the aim of soil protection and cultivation (Stone et al., 1989; Lal, 1990). Birkas et al. (2004) noted that the earthworm density declined with the intensity of tillage. However, surface and subsurface soil density and penetration resistance may increase naturally when using a no-tillage system (Birkas et al., 1998, 2004). These increases result from raindrop impact, soil particle distribution and structural failure. With no-tillage, natural increases in soil bulk density and penetration resistance usually are limited to the upper 0.15 m of the soil profile (Unger et al., 1998). The objective of this study was to determine effects of different tillage systems on sustainability of soil biological state in a long-term experiment under a semi-humid climate in Austria.

Evaluating the sustainability of different soil tillage practices using field measured electrical properties

Introduction Sustainable and soil conserving utilization of soils require knowledge of soil physical, chemical and biological properties affecting soil water, heat and nutrition regime. In Hungary soil moisture control prevention, elimination or moderation of extreme moisture situations is essential for sustainable land use and site-specific soil management (Varallyay, 2004). Soil tillage may play an important role in these actions (Soane & Ouwerkerk, 1994), especially under rainfed conditions, as in Hungary. Soils under tillage, however, have been found to be generally less stable than those under forest or grassland (Low, 1972). Soil physical degradation, reflected by changes in the shape of the soil water retention curve has harmful effects on soil water regime and on aeration (Stekauerova et al. 2006). When soil is degraded, the value of the soil water content at saturation becomes smaller and the slope of the retention curve at the inflection point, S also becomes smaller (Dexter, 2004). S has been found to be a useful measure of soil physical quality (Birkas et al., 2006). Soil properties vary strongly in space and time, thus, their determination is costly and time consuming. The need for more detailed information on spatial and temporal variation of soil properties (e.g. for precision agricultural utilisation) (Jolankai & Nemeth, 2002) lead to increasing interest over indirect methods for mapping soil properties. These methods allow overcoming the costs of detailed soil mapping based on traditional sampling. In-situ measurement of bulk soil electrical conductivity (ECa) is a quick and relatively easy method. The instrument readings show correlation with a number of soil properties that affect yield potential and environmental factors. This is why ECa measurements have been seen as one of the most promising methods. Several investigations have been carried out to study the relationship between the field measured ECa values (indirect measurements) and soil water, salt and humus contents, pH, mechanical composition and other soil properties. However, the relationship between data, obtained by indirect measurement techniques and soil hydraulic properties and soil quality indicators has not been widely examined yet. This paper studies the relationship between certain soil hydraulic properties, the soil quality indicator S and data, obtained from indirect field measurements in a long-term tillage experiment.

Riolittufa mállásának hatása a talajok vízvezető képességére

A kovaval atitatott, alig mallott riolittufat feltaro furasban elenk vizmozgas volt megfigyelhető a fizikai aprozodas soran felnyilt kőzetrepedeseknek koszonhetően, a meresek alapjan szamolt hidraulikus vezetőkepessege a valyog–homokos valyog fizikai talajfelesegű szintekehez hasonlo. A megjelenese alapjan „vulkani homok”-kent aposztrofalt, mallott riolittufa viz-vezető kepessege az előzetesen vartnal kisebb volt, nagysagrendekkel maradt el a „tenyleges” homok vezetőkepessegetől, megjelenese jelentősen lelassitotta a szel-venyekben tapasztalt vizmozgast; szamolt hidraulikus vezetőkepessege nagysag-rendileg az agyagos valyogehoz all kozel. A tapasztalt jelenseg oka egyreszt az, hogy a mallas soran a kőzetrepedesek eltomődtek, eltűntek, masreszt pedig az, hogy a mallott agyagos resz a durvabb szemcsejű „mallasi maradek” porusterebe uleped-ve a nedvessegmozgas szamara rendelkezesre allo porusteret jelentősen lecsokken-tette. Az eredmenyek azt jelzik, hogy a szőlőteruletek termőhelyi adottsagait meghata-rozo ...