Abstract. This study was conducted to evaluate the variability of the chemical properties of the soil of an oak forest affected by defoliation and the corresponding microbial abundance. Soil samples were collected from a control zone (zone 1) without outbreaks of defoliating insects and from a sample zone (zone 2) where the trees were affected by Lymantria dispar L. defoliation. The research was conducted to determine the changed conditions for soil microorganisms produced as a consequence of defoliation. The results indicated, by means of analysis of variance (two-way ANOVA, P = 0.05), statistically significant differences (P < 0.0001) with respect to soil hydrolytic acidity, pH, ammonium nitrogen, heterotrophic bacteria, nitrogen fixing bacteria from genus Azotobacter and fungi. The data revealed a low number of heterotrophic bacteria and low pH values in samples taken from the area affected by defoliation. Soils under stands of defoliated trees showed higher values with respect to soil acidity, ammonium nitrogen, fungi and nitrogen fixing bacteria Azotobacter. Moreover, the soil moisture, nitrate nitrogen, organic matter content, organic carbon, the number of heterotrophic bacteria and the number of bacteria from genus Azotobacter exhibited statistically significant seasonal differences between the two zones studied. The correlations between the tested parameters showed that soil parameters such as moisture content, soil acidity, pH, organic matter content, organic carbon, total nitrogen and nitrate nitrogen are important factors influencing the soil populations of aerobic mesophilic heterotrophic bacteria, fungi and nitrogen fixing bacteria in the studied forest ecosystem.

Afforestation and reforestation operations constitute an important part of the forest management, being crucial for the sustainability of forests. In such operations, there are three options to prepare the planting holes: manual, partly mechanized, and fully mechanized. Given the high cost of mechanized planting and the ergonomic issues of manual planting, one option which is worth exploring is using of augers, because they have the potential to mitigate and/or eliminate intense physical effort and aspects of some of the ergonomic problems. This study examines the early survival of seedlings following the use of augers to prepare the planting pits. Working time, fuel consumption and physical quality of the pits were evaluated on nine sites for two drill types differentiated by their diameter (150 vs. 200 mm). Time consumption was systematically higher when using the larger drill, while fuel consumption was not found to be statistically different. The larger drill systematically produced pits characterized by less physical quality in terms of resistance to penetration and shear strength, but the early survival of seedlings was higher when using this drill size. Survival probability modeled by means of logistic regression showed that pit size was among the factors that may affect the early survival of seedlings. The study concludes that the larger drill would be more appropriate to plant seedlings, but further studies should be arranged to see if long-term survival would be affected in this case.

From the multiple theses of eco-ethics, the study debates the complex relation between ethics – ethical principles and law – legislation in the field of environmental protection and durable development. Considering the differential – but also common – characteristics between natural laws and juridical ones that have an ecological signification, legislators must pass any law project while considering the needs of natural biosystems.

Providing high quality seedlings for use in forestry applications is one of the main challenges faced by the forest nurseries, and it depends on the practices used in such facilities. For instance, controlled experiments have shown that seedling growth is affected by the soils’ physical condition, which in turn is rather difficult to manipulate by the equipment used; this raises the question on whether changing the operational procedures could enable better physical properties of the seedbeds’ soils, in such a way that they will contribute to a better seedling growth. This study compares two seedbed tillage systems, termed as traditional (T, plowing, disk harrowing and cultivation) and minimal (M, scarifying and rototilling) in terms of physical properties of the soils and seedling growth, accounting for the variation induced by the local soil and climate conditions (three forest nurseries) as a separate factor. The results indicate highly significant gains in growth of the root collar diameter and shoot height for four tested species (pedunculate oak, common ash, wild cherry and Norway spruce), which accounted for 16 to 109% and for 10 to 134%, respectively, when using the M system. Root volume growth, which was tested for pedunculate oak, has also shown significant gains, accounting for 49 to 59% as of using M instead of T. In general, the seedlings resulted from the M treatment were found to be more homogeneous in terms of morphological characteristics, though the association and dependence between their features and physical properties of the soils were poorer. These gains in growth seem to be more related to the tillage systems rather than to local soil and climate conditions, as no or marginally significant differences were found to support their relation to the forest nurseries taken into study. The main conclusion of the study is that changing the regular seedbed tillage system by the minimal one could contribute not only at improving the growth of the seedlings, but also to the responsivity of forest nurseries.

Lignocellulosic biomass is used in various industries and its procurement involves a set of operations that are mainly done using equipment powered by internal combustion engines. The sustainability of forest operations may be characterized by balancing their energy inputs with those typically embodied in their outputted products. Forest tending operations are problematic because most of them cannot output marketable products while the data on their energy inputs are important for the forest management. Six of the most commonly used brushcutters equipped successively with discs and knives were tested to provide part of the data needed to run an energy analysis and to be able to characterize the energy inputs in release cutting operations by implementing the Gross Energy Requirements method. Fuel burning was found to have the greatest contribution (83–92%) in the total energy inputs (0.8–1.2 GJ/ha) of the studied operations and it was highly dependent on the efficiency of operations. Moreover, by simulation, it was identified that factors such as the assumed service life of equipment may significantly affect the outcomes of the analysis. Release cutting operations may be seen as important contributors in the energy balance of forest operations and data provided by this study may be of help for both forest management and more detailed and scaled analyses such as that of the Life Cycle Assessment.