However, see more variability in soil development is also high within each tree growing site (“plant’s zone of influence”) and sampling distance for estimation soil properties, based on soil probing, did not play a crucial role in defining soil characteristics for each tree. We believe that soil probing at a distance of 4–8 m from the subject

tree stem represented a reliable picture of soil characteristics and soil (site) variability for each selected subject silver fir tree. This could be confirmed by the highest coefficient of determination of height increment model on the base of soil associations as dependent variable in comparison to individual soil horizon thickness and soil depth. Similar findings were confirmed also in the case of specific basal area increment in the 2002–2005 period. In this case, soil probing well defines soil characteristics according to the “plant’s zone of influence” concept, but the effect of soil associations was greater than the effect of individual soil horizons. The results of our study emphasise soil as an important site parameter that influences tree height growth and basal area increments. As a result, soil should be considered

in forest management, especially in the adaption of thinning intensities Selleck Depsipeptide to the variations in micro topography over short distances. Our study revealed that addition to tree age and competition intensity, soil parameters e.g. soil depth, thickness of genetic soil horizons, share of soil types around each tree and soil associations were the factors controlling tree growth. Results do not allow us to highlight available water capacity as a key factor for tree growth, but

in the case of climate change with increasing temperature and evapotranspiration and decreasing amount of precipitation the AWC as a result of soil depth and lateral water inputs due to topography should be a key factor for tree vitality and distribution. The presence and thickness of particular soil horizons, which define soil types and consequently soil associations, seem to be simple and effective soil quality indicators. Such an approach is suitable mainly for natural, undisturbed soils, such as soils in uneven aged forests, and for areas where short-range spatial variability Adenosine triphosphate in environmental parameters and soil development prevails. The practicability of such an approach cannot be questioned because soil type and soil association assessment, which are based on expert judgement in the field, are cost effective compared with the expensive and time-consuming soil chemical and physical analyses. In the future, we also suggest the use of high-resolution digital elevation models, which could be obtained from airborne laser scanning ALS and LiDAR data, digital soil mapping using digital terrain analysis and statistical modelling integrated into GIS.