The buffering curves (determined after Arrhenius method) (fig. 2) have been drafted and the buffering areas have been measured (tab. 2) in order to estimate the buffer capacities of the South Poland soils. The influence of the physico-chemical soil properties on the buffer capacities of soils has been estimated for all genetic horizons of 30 soil profiles (tab. 1 and 2 contain results for 10 selected profiles) which belong to various taxonomic units of the Proszowice Plateau, the Niepołomice forest, the Podhale region and the Tatra Mts. The buffering of soils depends mainly on the soil reaction, the total exchangeable bases and the hydrolitic acidity (tab. 3). Podzols and brown soils (especially under forestes) are the most sensitive to the acid effect, while the most resistant are chernozems and alluvial soils as well as low peat soils. High peat soils and podzols are the most resistant to the base effect while chernozems are the least resistant ones (fig. 4). The resistance of different genetic horizons of the examined soils is not alike and results from the presence of differentiated buffers conditioned by various soil forming processes (fig. 3).
Long term drilling can change soil chemical properties. It refers mainly to P, K and Corg. concentration as well as acidity of surface layer of soil. The main reason for these changes is the superficial usage of mineral fertilizers and modification in plant root distribution. To qualify soil biological activity one can use many indicators - numbers of soil fauna, number of particular microorganism groups or soil enzyme activity. Among them mostly dehydrogenase activity should be considered. Its activity depends on soil chemical properties. That is why dehydrogenase should be regarded as a very sensitive indicator for all changes occurring in the soil environment.
A new index of suppleness of soil reduction SSR is proposed to agrochemical characteristics of soil which may be considered as an index of soil fertility. Established values 25 mV/24 hours as threshold between low and high suppleness on reduction of soil. The SSR index may be practically useful for a characteeristics of soils.