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• Self-thinning models were developed for several types of uneven-aged forests. • Pure stands are denser than mixed stands but their maximum stand density lines are steeper compared to mixed stands.. • The proportion of beech increases the intercept and slope of the maximum stand density line. • Single-tree selection stands have the greatest intercept and the steepest slope of the maximum stand density line. • Quantile Regression and Stochastic Frontier Analysis predictions are congruent. The self-thinning law describes the progressive mortality of growing trees in crowded even-aged stands because of competition. In uneven-aged stands, however, density-dependent mortality is relatively poorly known. We developed density-dependent self-thinning models for mono-species and multi-species uneven-aged stands. Three models for mono-species Picea abies , Abies alba and Fagus sylvatica stands, four models for mixed conifer/broadleaf stands and a model for single tree selection stands as a specific type of uneven-aged forest were parametrized by Quantile Regression (QR) and Stochastic Frontier Analysis (SFA) using data from n = 31,612 forest inventory plots in Slovenia. The average slope of the self-thinning line in uneven-aged stands of −1.422 was statistically significantly lower than Reineke's slope. Maximum stand density was higher in mono-species stands than in multi-species stands. The higher the proportion of beech in a stand, the higher the intercept and slope of the maximum stand density line. In single tree selection stands, the intercept and the slope of the maximum stand density line were highest and statistically different from all other types of uneven-aged forests. Species mixture had an impact on the slope and intercept of the self-thinning line. The slopes of the self-thinning lines differed between the studied types by up to 36% and 69% in the SFA and QR models, respectively, while the intercepts differed by up to 13% and 24%, respectively. However, maximum stand densities differed significantly only between compositionally very dissimilar stand types, such as Fagus sylvatica- or Picea abies- dominated mixtures versus other broadleaf mixtures (e.g., Quercus petraea , Carpinus betulus). The SFA predictions of maximum stand densities were systematically lower and less varying than the QR predictions, but not statistically different. The models can be used to constrain individual tree growth models in uneven-aged forests and to estimate the onset of inter-tree competition in irregular stands. [ABSTRACT FROM AUTHOR]

Private forest owners' involvement in forest management has been frequently examined through the attitudes, values, beliefs, objectives and motivations associated with owning and managing forestland. Owners' views on forest management do not always align with those of policymakers who believe forest owners do not actively manage their forests. However, empirical studies on forest owners' conceptualisations of forest management are scarce. To determine how private forest owners in Europe conceptualise forest management, a survey (n = 1140) was undertaken in seven European countries (Portugal, France, the United Kingdom, the Czech Republic, Slovenia, Slovakia and Romania). The owners were asked to indicate their level of agreement with 19 pre-tested statements defining forest management on a five-point Likert scale. Classification and regression trees were used to explain the major factors that influenced owners' conceptualisations. Owners primarily conceptualised forest management as preserving forests for future generations and considered “a good business opportunity”, “an opportunity to earn additional money” or a “source of subsidies” less important. Their understanding of forest management as a mixture of forest maintenance, ecosystem stewardship and economic activity does not match with alleged policy makers’ views. Property size, age and Eastern/Western countries were the most relevant predictors of definitions of forest management. Small-scale forest owners from Western Europe considered ecosystem orientation more important, while owners from Eastern Europe considered economic aspects and forest maintenance more important. These differences might be associated with the socio-political system dynamics in Europe in the 20th century and changing values in post-modern society. Policymakers must be aware of the different forest management paradigms among forest owners in Eastern-Central and Western Europe when designing European forest policies. [ABSTRACT FROM AUTHOR]

• Recruitment of beech, spruce and fir in uneven-aged stands studied on 200 m2 plots. • Optimal and critical levels of 18 influential factors determined with the Tobit model. • Stand basal area and the proportion of target tree species are key factors. • Stocking control is efficient for regulating recruitment of spruce and beech. • Fir recruitment is weakly limited by stand density and largely stochastic. Tree recruitment models are important for predicting the dynamics of uneven-aged forests. Previous studies of recruitment of European beech, Norway spruce and silver fir have shown different ecological amplitudes of these species. However, recruitment in uneven-aged stands and the values of environmental factors at which the greatest and poorest recruitment can be expected remain poorly explained. The main objectives of this study were to 1) explain how 39 stand, site and climatic factors and their interactions influence the number of recruited trees in uneven-aged forests; 2) determine the optimal and critical ranges of influential factors, including stand basal area, number of trees, proportion of tree species, shade casting, soil pH, site productivity, temperature and precipitation; and 3) estimate the maximum expected response of recruitment to changes in stand density while controlling for the effect of other limiting factors. A Tobit censored regression model was used to consider that the observed range of the number of recruited trees is censored at zero. The models were parametrized and validated using 30,963 forest inventory plots (200 m2 each) in uneven-aged forests in Slovenia. The models, which used 9 stand, 6 site and 3 climatic factors, explained 15 %, 10 % and 8 % of the total variation of the number of recruited spruce, fir and beech, respectively. Stand structure was the most important factor, with stand basal area (BA) and the proportion of the studied species having the greatest effect. Site factors including soil pH and rockiness were important for fir recruitment. The number of recruited beech and spruce was positively influenced by decadal precipitation. Higher temperatures decreased recruitment of spruce. Beech was the only species sensitive to shade casting. Recruitment of beech was higher if shade was imposed by tree species other than beech. The optimal and critical ranges of limiting factors differ between species. The model suggests that the optimal stand basal area for recruitment of beech is ≤ 19 m2/ha, which is higher than that for spruce (≤ 16 m2/ha) but lower than that for fir (≤ 28 m2/ha). The maximum predicted response of the studied species to changes in stand basal area shows that stand density control is efficient for regulating recruitment of spruce and beech, but not for fir. The suggested sensitivities and threshold values may be used in individual tree growth models or simulation–optimization studies in support of forest management decisions. [ABSTRACT FROM AUTHOR]

Abstract: Silver fir decline was investigated based on changes in spatial distribution of fir, fir abundance in forest stands, dbh (age) structure of fir, and abundance of fir regeneration. The authors used a large-scale approach to study the dynamics of silver fir over nearly 40 years. Based on Silva-SI, a spatial information system, the majority of total forest area in Slovenia was analysed for changes in the distribution of silver fir in the period 1970–2008 using artificial neural networks (ANNs), with respect to site, stand, and forest management variables. Additionally, changes in abundance of silver fir (hereafter fir) in the same period were analysed with a general linear model, while changes in the dbh structure of fir and fir regeneration were analysed with non-parametric tests. Most selected indicators confirmed the hypothesis of fir decline in the period 1970–2008, as evidenced by a reduction in the area of forests with a share of fir in the total growing stock >25% (from 18.9% to 9.5% of total area), a reduction in the share of fir in the growing stock of forest stands (from 17.5% to 7.5%), ageing of the fir population, and a disproportionate share of fir saplings in the total saplings relative to fir''s share in the growing stock of forest stands. A 1.5% increase in fir distribution area in the observed period contradicts the decline hypothesis. ANNs showed that the spatiotemporal dynamics of fir was most affected by four variables: forest type, share of fir in the potential natural vegetation, mean annual precipitation, and mean annual temperature. The latter two, together with the growing stock at the start of study period, the degree of connectivity between fir stands, and bedrock type, were significant predictors of decline of fir abundance in forest stands. Significant differences in spatiotemporal dynamics and changes in fir abundance were found between forest types representing a complex of site conditions and past forest management. A further decline of abundance of fir on a large spatial scale in the next decades is expected. Conservation of fir in forest stands will depend mainly on the successful regeneration of fir and sufficient recruitment. [Copyright &y& Elsevier]

Based on data acquired from the spatial information system Silva-SI, the majority of the entire forest area in Slovenia (22,220 forest compartments with a total area of 7446km2, classified into eight forest categories) was analysed for changes in the distribution of European beech (Fagus sylvatica L.) in the period 1975–2005 using a binary logistic regression model in terms of selected site, stand and management variables. Additionally, changes in the abundance of beech in forest stands in which beech was present at the beginning and the end of the analysed period were analysed. Beech expanded its area by more than 1200ha per year on average, i.e. the annual expansion rate amounted to 0.24%. Among the 18 studied variables, three site, four stand and no management variables were included in the binary logistic regression model of beech expansion. Beech expansion was more pronounced at lower altitudes, on sites with steep topography, and on sites with a higher proportion of beech in potential natural vegetation. The probability of beech expansion reduced by a factor of 0.54 when the distance to the nearest compartment with beech increased by 1km. Among other stand variables, the proportion of early successional phases and the proportion of silver fir (Abies alba Mill.) and Norway spruce (Picea abies (L.) Karst.) also influenced the expansion of beech. During the observed period the growing stock of beech almost doubled, its proportion in total growing stock increasing from 27% to 32%. Significant differences were found in changes of beech proportion in the total growing stock among different forest categories; a decrease in the beech proportion was registered in alpine coniferous forests and thermophilous deciduous forests, while in other forest categories the proportion of beech increased. The recent development of forest stands and their current structure indicate a further expansion of beech and an increase in the proportion of beech in forest stands. [Copyright &y& Elsevier]

• Psychological landownership (PL) has been neglected in landscape research. • Forest owners' motives for PL are having a place to dwell and building self-identity. • Management duration and work with young forest stands strengthen PL. • Regional variations and concentrations of PL indicate hotspots/coldspots. • PL is a strong barrier to land degradation but it also hinders timely inheritance. Legal ownership of land defines the formal relationship between a landowner and land. Besides legal ownership, there is also psychological ownership which landowners can develop toward land. Despite the abundant literature on the relationships between landowners and land, it remains unclear under which circumstances a sense of ownership over land occurs and what impacts individual feelings may have on landscape dynamics if aggregated or scaled up. Building upon the psychological ownership theory, we interviewed 442 private forest owners in Croatia about the benefits of landownership. By using a Multiple Indicators Multiple Causes (MIMIC) structural equation model and local spatial autocorrelation statistics, we 1) analyzed whether landownership benefits correlate to three motives for psychological ownership, i.e. having a place, efficacy and effectance, and self-identity; 2) analyzed the factors stimulating the motives; and 3) located the areas of spatial concentration of psychological landownership (i.e. hotspots/coldspots). Landownership benefits showed a strong association with the corresponding motives indicating that private forest owners experience landownership as a connection between the self and forest. Physical work in the forest and tending young forests increase psychological landownership. The land tenure system and duration of ownership plays no role. The biggest hotspot appeared in the most developed area, possibly preventing land transfer. Coldspots, in contrast, emerged across the country, pointing to land which could potentially change ownership after the land market regulation expires in 2023. The findings expand the understanding of land possession beyond the dis(investment) paradigm and help predict hotspots of land transfers at local to regional scales. [ABSTRACT FROM AUTHOR]