Question We connected tree‐census and dendrochronological research data (74.2 ha) in order to answer the following questions: How do we apply an individual‐based approach, which allows us to abandon the traditional patch model, in the research of disturbance history through spatial scales? What is the disturbance history of the natural forest? How do we understand the influence of the Kyrill storm, which affected the reserve on 18 January 2007? How does the disturbance history in dendrochronological records correspond to real disturbances? Location Žofínský Prales (48 °40′ N, 14 °42′ E, 735–830 m a.s.l., granite, Czech Republic) Methods Repeated tree‐censuses (>20 000 trees) were carried out in 1975, 1997 and 2008. These surveys served as the basis of dendrochronological research, during which 3 020 trees were sampled. A boundary line (BL) approach and geostatistical techniques were used to detect disturbance intensity and its spatial pattern. Results The mean disturbance rate was 11.0% canopy loss per decade (maximum 33.7%) in the core zone. Bordering forests were directly affected by humans after 1800. A maximum of nine disturbance events were recorded per tree, but there were also 3% of non‐suppressed trees without records of disturbance events. The Kyrill storm represented a singular event in the forest history from the point of view of its exceptional spatial pattern (ranges up to 320.0 m), but not from the perspective of disturbance intensity. The relationship between disturbance intensity (y) and the range of spatial autocorrelation (x) can be explained by the equation y = 10.6863 + 0.0783*x (R2 = 0.546, P = 0.009). The spatial variability of releases ≥50% of BL corresponds to real disturbance events, while the insertion of weak releases led to the overestimation of range. The frequency of releases was affected by a decrease in air pollution at the beginning of the 1990s. Conclusions Effects of small‐scale disturbances predominate in forest dynamics. Disturbance intensity was often not directly in accordance with the range of spatial autocorrelation. The ecological role of disturbance is therefore biased if disturbance intensity is used as the sole criterion. The results suggest the importance of historical and geographical contingency in ecosystem development.

Soil variability was assessed in a 74.2-ha area within the Ž ofínský prales natural forest. Parameters evaluated for 1765 soil profiles inside 353 graticule plots were as follows: (1) thickness of organic horizons, (2) thickness and form of mineral horizons, (3) humus form (HF), (4) soil taxonomic unit (STU) and (5) anomalies. In addition, soil reaction (pH KCl ) and oxidizable carbon content (C ox ) were measured in the laboratory for 734 samples from the upper mineral (A) and lower mineral (B) horizons. The most frequently occurring humus form was mor followed by moder, hydromor and peaty T-horizon. Entic Podzols, Dystric Cambisols, Haplic Cambisols, Albic Podzols, Histic (or Haplic) Gleysols, Endogleyic Stagnosols, Fibric or Hemic or Sapric Histosols and Stagnic Gleysols were all present at the site despite its homogeneous geological bedrock. Overall coefficient of variance (CV) was lower in terrestrial soils compared with (semi-)hydromorphic soils. Overall variance decreased in both soil groups with increasing depth, as did CV differences between the fine (up to 10 m) and the locality scales. The lowest CV values occurred for C ox and pH KCl . The CV values differed between STUs as well. Compared to lower horizons, variograms of upper horizons showed greater autocorrelation at the intermediate spatial scale (10-320 m)-ranging from 50 to 150 m. Semivariance values, however, reached 70-80% of sill already at a distance of 10 m. The most significant factor of variability at all studied spatial scales is presumably the soil disturbance regime, followed by terrain micro-topography and the effect of tree species.

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