OPEN Repository

Welcome to OPEN - the Repository of Open Scientific Publications, run by the Interdisciplinary Centre for Mathematical and Computational Modelling, University of Warsaw, previously operating as the CeON Repository. The Repository enables Polish researchers from all fields to openly share their articles, books, conference materials, reports, doctoral theses, and other scientific texts.

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22799 archived items

Recent Submissions

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Effect of mechanization level on manpower needs in forestry
(Instytut Badawczy Leśnictwa (Forest Research Institute), Komitet Nauk Leśnych PAN (The Committee on Forestry Sciences of the Polish Academy of Sciences), 2014-12-15) Błuszkowska, Urszula; Nurek, Tomasz; Warsaw University of Life Sciences – SGGW, Faculty of Production Engineering
High work consumption in forest operations is above all the result of the character and task realization mode in works undertaken in forestry. Development of mechanization in forest management activities allows to considerably decrease manpower needs. In the present study, there were analyzed the possibilities of reduction of work consumption by improving the mechanization level of forest works. The method was developed to consider the following assessments: 1) variant W1 – basic option comprising factual work consumption values in works carried out on the area administered by the Regional Directorate of State Forests (RDLP); 2) W2 – showing the effect of 25% upgrade of works to a higher level of mechanization; 3) W3 – showing the effect of 50% upgrade of works to a higher level of mechanization; 4) W4 – comprising analogous calculations to those in variant W1 , but work consumption upgrading was 75%. Simulation calculations revealed considerable differences in needs for labor of different categories of forest workers. On the other hand, with increasing mechanization level, there increase the demands concerning worker qualifications, e.g. a harvester operator must be trained for about 2 years, and the training has to include both simulator exercises (first using software and next – harvester simulator) and field work under supervision to gain sufficient experience. The introduction of higher levels of mechanization into forest operations, and hence considerable reduction of jobs for unqualified workers who are replaced by qualified employees, can help decreasing work consumption in forest operations.
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Aerial treatments in forest protection – research methodology
(Instytut Badawczy Leśnictwa (Forest Research Institute), Komitet Nauk Leśnych PAN (The Committee on Forestry Sciences of the Polish Academy of Sciences), 2014-12-15) Rowiński, Robert Stefan; Air Force Academy in Dęblin
Treatment effectiveness in forest protection against harmful insects depends not only on pesticide efficacy of the product applied, but also on a number of other factors including assurance that a given insecticide reaches the pest living in the canopy. In the treatments with the use of aerial equipment (silva-aerial) it is advisable to consider species and age diversity of protected tree stands. The paper presents research methodology on the assessment of spray structure and density, penetration of spray droplets into the canopy as well as a degree of coverage and incorporation in tree crowns. The methodology proposed takes into account characteristics of the forest area studied and its surroundings, as well as the parameters and equipment of the measurement line. There were determined: operation requirements for the aircraft and its test and registration equipment as well as demands on pilot qualifications, flight performance on the measurement line and weather conditions allowing for conducting test trials. In the paper, there are presented a set of values and mathematical formulas needed for the analyses. Taking into account ecological threats, there were included the methods on evaluation of spray drift of the liquid distributed over the forest.
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Determination of lime tree (Tilia begonifolia Stev.) stems form based on quantitative parameters (Study area: Shafaroud forests of Guilan province, Iran)
(Instytut Badawczy Leśnictwa (Forest Research Institute), Komitet Nauk Leśnych PAN (The Committee on Forestry Sciences of the Polish Academy of Sciences), 2014-12-15) Sendi, Mohammad Rasoul Nazari; Navroodi, Iraj Hassanzad; Poorbabaei, Hassan; Milan, Mohammad Sheikhkanlu; Bakhshandeh, Behzad; University of Guilan, Faculty of Natural Resources, Forestry Department, Guilan, Iran; Lorestan Universitiy, Iran
The lime tree is one of the rare and valuable species that found in the Hyrcanian moist forests with economic as well as ecological value. Identification of the quantitative and qualitative features of this species is important. In order to investigate the stem form of this species in the Shafaroud forests of Guilan Province, 141 lime trees in 39 plots were analyzed during the four stages of small pole, pole, saw-timber, and maturity. In each plot, stem-diameter at different heights was measured by using the Spiegel Relaskop. Measurements and analyses included diameter at breast height(d.b.h.) and total height. Same parameters was calculated: stem form factor based on diameter, stem form factor based on volume, form quotient, slenderness factor, ratio of stem height to total height, ratio of stem volume to total volume, correlation, and coefficient of determination to describe stem form factor. The results showed that the average stem form factor based on diameter was 0.554. The average stem form factor based on volume was 0.576, average form quotient was 2.32 and slenderness factor was 35.04%. The average ratio of stem height to total height was 82.45. In addition the results indicated a strong relationship between diameter at breast height and trunk coefficient. The ratio of stem volume to total volume revealed that 64.44 of lime volume is located in the bottom half of the trunk. The value of the parameters described here is towards a better description of stand characteristics. Obtained results indicating stability for natural lime tree in Iran.
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Forests and forestry in Poland and other EU countries
(Instytut Badawczy Leśnictwa (Forest Research Institute), Komitet Nauk Leśnych PAN (The Committee on Forestry Sciences of the Polish Academy of Sciences), 2014-12-15) Zając, Stanisław; Kaliszewski, Adam; Młynarski, Wojciech; Forest Research Institute, Department of Forest Resources Management, Sękocin Stary
The paper provides general information about forests and forestry in Poland against a background of other EU Member States. Based on the data published in various international sources of statistical data it presents the information of forest resources, forest health condition, protection of forests, occurrence of forest fires, employment in forestry and related sectors, as well as selected aspects of production and trade of wood and wood products and also generation and use of renewable energy. The paper concludes that Poland is characterized by vast forest and timber resources, however in view of a large area of the country and large population share of forest lands in the total area of the country and the average forest area per inhabitant are low. The high share of protected areas makes Poland one of the leaders in forest protection, however Polish forests are very vulnerable to fires. Poland is a significant producer of wood-based panels, sawnwood and pulpwood, as well as paper and cardboard.
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Longitudinal analysis of annual height increment differentiation in Scots pine (Pinus sylvestris L.) stands of different age classes
(Instytut Badawczy Leśnictwa (Forest Research Institute), Komitet Nauk Leśnych PAN (The Committee on Forestry Sciences of the Polish Academy of Sciences), 2014-12-15) Zawieja, Bogna; Kaźmierczak, Katarzyna; Poznań University of Life Sciences, Department of Mathematical and Statistical Methods; Poznań University of Life Sciences, Faculty of Forestry, Department of Forest Management
In the study, the measurements of Scots pine height increments were used to compare the increments of pine trees of different age classes. All of the analyzed trees were growing in stands located on fresh mixed coniferous forest sites. The study concerned a 10-year period of growth of 8 tree age classes. Due to variation in climate conditions, all trees were studied over the same calendar period. Longitudinal analysis was used to compare different age classes of trees with reference to the increments in height. This procedure had not been previously used for such purpose. The results obtained did not confirm the hypothesis of parallel profiles implying that there existed differences in the growth of trees in various age groups.