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Wpływ sprawozdania finansowego na kształtowanie wizerunku nadleśnictwa w opinii interesariuszy wewnętrznych
The influence of some morphological characteristics of pine logs on the results of calculating their volume by different methods
The Role of Human Capital in an Organisation - A Case Study of the ‘State Forests’ National Forest Holding in Poland
Human capital is a key element necessary for the smooth operation of an organization based on sustainable development. It is not only important for building strategy but also affects the performance of day-to-day operations. Managers must constantly monitor the changes taking place around the organization and make quick decisions in line with sustainability. They enable the organization to adapt to current market conditions and meet closed-loop requirements. These solutions are an important issue in forest management organizations. Considering the expanded mission of forests, it is clear that the role of forests today is much broader than just protecting biodiversity. Forestry institutions need adequate staff and human resources to effectively carry out forest management tasks and properly analyze trends and patterns of the sustainable use of forest resources. The purpose of the article was to analyze and evaluate human capital through its commitment to the organization’s tasks within the framework of sustainability. The research involved a sample for employees working in a selected unit of the State Forest Holding in Poland. The research was based on an anonymous employee survey on job engagement. The following aspects were assessed, commitment to the organization, sense of responsibility to the organization, interest in the work, and willingness to make sacrifices for the company in order to meet the demands of a modern forestry company oriented to the requirements of the new forestry strategy. Our reanalysis showed that gender and job type do not have a significant impact on commitment. However, an employee’s age and length of service do influence the behaviour and commitment of state forestry employees.
The Influence of the Accelerated Aging Process on the Compressive Strength of Wood Treated with Components of a Salt Fire Retardant
This paper presents the results of research on the influence of the components of salt flame retardants on the compressive strength of wood depending on the time of accelerated aging. The effect of the agent was assessed on the basis of the change in the strength of treated wood compared to that of untreated wood. In addition, a statistical analysis of the obtained results was used to determine which of the components most significantly affect the changes in the compressive strength of wood along the fibers, and to what extent. It was found that extending the aging process time in the case of control and boric acid-protected samples did not significantly change the strength properties. It has also been found that some compounds contained in fire retardant have an antagonistic effect related to the compressive strength of wood.
Poziom optymalizacji przestrzeni wypełnienia pojazdów transportowych w logistyce jako pochodna wymiarów sortymentów drzewnych
Effect of logging residue removal and mechanical site preparation on productivity of the subsequent Scots pine (Pinus sylvestris L.) stands
Abstract Key message Removal of logging residue negatively affected tree diameter and height, but had no significant effect on the basal area of the subsequent stand (in the mid-term). On the other hand, different methods of mechanical site preparation (bedding, plowing furrows, and trenching) had no effect on tree growth 1 year after planting, but had a significant effect on tree diameter, tree height, and basal area in the mid-term. Bedding treatments could have a significant positive impact on the productivity of the subsequent Scots pine stands, even when planted on sandy, free-draining soils. Context Increased use of logging residues in forests may address the growing demand for renewable energy. However, concerns have arisen regarding the depletion of the forest soil, resulting in a decrease in the productivity of the next forest generation. Identifying the drivers of forest growth may be the key to understanding the relationship between logging residue removal and stand productivity. Aims Quantifying the effect of three mechanical site preparation methods (bedding, plowing furrows, and trenching) combined with five methods of logging residue management (complete removal, comminution, incineration, leaving whole, comminution with, and without mixing with topsoil) on growth of subsequent Scots pine stands, 1 year and 12 years after planting. Methods The experiment was set up as a randomized complete block design of 45 plots with three replications of combinations of three mechanical site preparation methods and five logging residue treatment methods. Results The effects of the different methods of mechanical site preparation were not significant 1 year after planting but bedding treatment caused increase in DBH, tree height, and basal area after 12 years. Various methods of logging residue management did not cause any differences in the survival rate nor the basal area of the next-generation stands; however, there was a significant influence on tree sizes. Moreover, the effects changed with time; in plots with a complete removal of logging residues, the trees were the highest 1 year after planting, but after 12 years, their height and DBH were the lowest. Conclusions It can be concluded that bedding treatments could have a significant positive impact on the productivity of the subsequent Scots pine stands. No effect found of different logging residue treatments on the productivity of Scots pine stands further confirms that the increased removal of biomass from the forest environment does not necessarily result in its rapid degradation. Observations at longer term are however needed to obtain the full spectrum of responses to logging residue removal.
Data Mining in the Analysis of Tree Harvester Performance Based on Automatically Collected Data
Data recorded automatically by harvesters are a promising and potentially very useful source of information for scientific analyses. Most researchers have used StanForD files for this purpose, but these are troublesome to obtain and require some pre-processing. This study utilized a new source of similar data: JDLink, a cloud-based service, run by the machine manufacturer, that stores data from sensors in real time. The vast amount of such data makes it hard to comprehend and handle efficiently. Data mining techniques assist in finding trends and patterns in such databases. Records from two mid-sized harvesters working in north-eastern Poland were analyzed using classical regression (linear and logarithmic), cluster analysis (dendrograms and k-means) and Principal Component Analysis (PCA). Linear regression showed that average tree size was the variable having the greatest effect on fuel consumption per cubic meter and productivity, whereas fuel consumption per hour was also dependent, e.g., on distance driven in a low gear or share of time with high engine load. Results of clustering and PCA were harder to interpret. Dendrograms showed most dissimilar variables: total volume harvested per day, total fuel consumption per day and share of work time on high revolutions per minute (RPMs). K-means clustering allowed us to identify periods when specific clusters of variables were more prominent. PCA results, despite explaining almost 90% of variance, were inconclusive between machines, and, therefore, need to be scrutinized in follow-up studies. Productivity values (avg. around 10 m3/h) and fuel consumption rates (13.21 L/h, 1.335 L/m3 on average) were similar to the results reported by other authors under comparable conditions. Some new measures obtained in this study include, e.g., distance driven in a low gear (around 7 km per day) or proportion of time when the engine was running on low, medium or high load (34%, 39% and 7%, respectively). The assumption of this study was to use data without supplementing from external sources, and with as little processing as possible, which limited the analytic methods to unsupervised learning. Extending the database in follow-up studies will facilitate the application of supervised learning techniques for modeling and prediction.
Relationships between selected phenolic compounds and microbial abundance in grassland soils in the Obra River valley: a preliminary study
Celem pracy była ocena zależności pomiędzy wybranymi związkami fenolowymi, a liczebnością mikroorganizmów w glebach użytków zielonych. Obiektem badań były wierzchnie warstwy gleby (0–20 cm) użytków zielonych położonych wzdłuż rzeki Obry (Nizina Wielkopolska, centralna Polska). Badania terenowe przeprowadzono we wrześniu 2022 roku. Na badanym obszarze wybrano pięć jednostek syntaksonomicznych roślinności: <i>Molinietum caeruleae</i>, <i>Alopecuretum pratensis</i>, <i>Arrhenatheretum elatioris</i>, <i>Lolio-Cynosuretum</i> oraz zbiorowisko <i>Poa pratensis-Festuca rubra</i>. Jednokierunkowy test ANOVA dla pH wykazał statystycznie istotne różnice między użytkami zielonymi (dla pH<sub>H2O</sub> p=0,000, a dla pH<sub>KCl</sub> p=0,000). Liczebność bakterii heterotroficznych (p=0,000), promieniowców (p=0,001) i grzybów (p=0,014) była również cechą istotnie różnicującą jednostki roślinności użytków zielonych. Jednokierunkowy test ANOVA wykazał, że spośród wszystkich analizowanych związków fenolowych tylko dwa były się istotne: kwas wanilinowy (p=0,003 i katechina (p=0,002). Nasze badania wskazują na dodatnią korelację promieniowców z kwasem cynamonowym i kawowym, bakterii heterotroficznych z kwasem p-kumarowym i ferulowym oraz katechiną, a grzybów z kwasem galusowym i katechiną. Ponadto, biorąc pod uwagę cechy istotne statystycznie, można stwierdzić, że <i>Molinietum caeruleae</i> wykazuje inną strukturę w porównaniu z innymi jednostkami wegetacyjnymi, <i>Arrhenatheretum elatioris</i> i <i>Lolio-Cynosuretum</i> są podobne, podczas gdy zbiorowiska <i>Poa pratensis-Festuca rubra</i> i <i>Alopecuretum pratensis</i> wykazują odmienną strukturę od pozostałych. Badania środowiskowe coraz częściej koncentrują się na potrzebie zwiększenia akumulacji węgla organicznego w glebie. Poznanie relacji między związkami fenolowymi i mikroorganizmami w glebach użytków zielonych jest niezwykle ważne w tym aspekcie. Właściwe zarządzanie użytkami zielonymi jest ważnym elementem ochrony środowiska.
Zależności między wybranymi związkami fenolowymi a aktywnością mikroorganizmów w glebach użytków zielonych w dolinie rzeki Obry
Modeling the Effects of Strict Protection of Forest Areas—Part of the Provisions of the EU Biodiversity Strategy 2030
The case study included approx. 0.5 million ha of forest areas in Poland that are managed by the Regional Directorate of State Forests. The objective was to assess the impact of four different scenarios restricting the size of forest areas available for commercial use. Based on different criteria, each scenario set aside 10% of the total land area for strict protection on forested land, which is in line with the EU Biodiversity Strategy 2030. The economic impact (volume of reduced wood raw material) was statistically estimated for each of the four scenarios. It was confirmed that the layout of forest habitats is essential for specific limitations in forest production. For the optimal implementation of the provisions of the strategy, a balance in the selection of social, economic, and natural elements must be considered. This protects primarily the most valuable natural habitats characterized by the highest level of biodiversity, age diversity, and dispersion within the studied forest unit. The presented results may support decision-making processes used to maximize biodiversity protection while minimizing the negative economic impact of this environmental protection.
Influence of reclamation and slope aspect on the selected properties of constructosols developed on a reclaimed landfill in Czmoń. Part I: Basic physical and chemical soil properties
Dynamiczny rozwój cywilizacyjny i wzrost ilości odpadów komunalnych w Polsce wymusiły konieczność efektywnego zarządzania składowiskami odpadów oraz ich rekultywacji. W artykule przeanalizowano wpływ wystawy stoków, położenia na stoku i czasu jaki upłynął od zakończenia rekultywacji na wybrane właściwości fizykochemiczne powierzchniowych poziomów glebowych na zrekultywowanym składowisku w miejscowości Czmoń, w województwie wielkopolskim. Badania obejmowały analizy gleby w warstwach powierzchniowej (0–10 cm) i podpowierzchniowej (10–20 cm) w różnych częściach składowiska. Oznaczono między innymi uziarnienie, odczyn, zawartość węgla organicznego (TOC) i węglanu wapnia (CaCO₃) oraz pojemność sorpcyjną gleby (CEC). Na podstawie analizy statystycznej uzyskanych wyników, stwierdzono, że wymienione czynniki wpłynęły na zróżnicowanie właściwości gleby w zależności od wieku składowiska i orientacji stoków. Zgodnie z oczekiwaniami uziarnienie badanych gleb był związane bezpośrednio z działaniami rekultywacyjnymi. Gleby w obrębie nowej części składowiska charakteryzowały się wyższymi wartościami pH, CEC i zawartością CaCO₃. Gleby w obrębie starszej części składowiska cechowały się szerszym stosunkiem C/N. Stwierdzono także zależność pomiędzy ekspozycją badanych stoków (N - S), a wybranymi właściwościami gleb. Badania te podkreślają znaczenie dobrze zaprojektowanych działań rekultywacyjnych, które pozwalają na spełnienie funkcji biologicznej gleby utworzonej na tego typu składowiskach oraz ograniczenie negatywnego wpływu na środowisko. Badania te stanowią istotny wkład w rozwój wiedzy na temat długoterminowych efektów rekultywacji składowisk odpadów.
Effect of herbal feed additives on goat milk volatile flavor compounds
The aim of this study is to investigate the effects of herbal supplements administered to goats on sensory quality and volatile flavor compounds in their milk. The experiment was conducted on sixty Polish white improved goats randomly allocated into five feeding groups (four experimental and one control) of twelve goats each. The trial lasted 12 weeks. The experimental animals received supplements containing a mixture of seven or nine different species of herbs at 20 or 40 g/animal/day. The control group received feed without any herbal supplements. Milk obtained from experimental and control groups of animals was characterized by a low content of aroma compounds, with only 11 chemical compounds being identified. Decanoic methyl ester, methylo 2-heptanone and methylo-butanoic methyl ester had the highest share in the total variability of the tested aroma compounds (PCA). During the sensory evaluation, the smell and taste of most of the samples were similar (p > 0.05). However, the addition of herbal feed supplements lowered the concentration of Caproic acid (C6:0), Caprylic acid (C8:0) and Capric acid (C10:0), which caused a significant reduction in the goaty smell of milk. The obtained results indicate that the studied herbal supplements can reduce the intensity of goaty smell and allow goat milk production without modification of other sensory features.