Wyniki wyszukiwania - BazTech

1

Evaluating Repeatability of RTK (GPS and Galileo/GPS) performance in the analysis of points located in areas with and without obstructions

Pırtı Atınç, Yucel Ali

Reports on Geodesy and Geoinformatics

|

2022

|

Vol. 113

11--20

EN

Galileo is Europe’s Global Navigation Satellite System (GNSS), which provides improved positioning and timing data with significant benefits for many European services and users. Galileo enables users to know their exact location with greater precision than other available systems. Access to the Galileo signal in the obstructed and unobstructed environment provides benefits and opportunities for work, thanks to the improved performance and accuracy. The use of a Galileo-enabled receiver increases the number of satellites in view significantly. When compared to the performance of single-constellation receivers, this significantly reduces the time required to obtain a position with centimetre-level accuracy. The results indicate the current Galileo constellation’s suitability for high-precision RTK applications, as well as improved availability, accuracy, reliability, and time-to-fix in the obstructed and unobstructed environments. The results of RTK GPS and RTK GPS/Galileo obtained at different times of the same day by using two reference points were compared. The results of this study illustrate that integrating RTK GPS system with Galileo is favorable for surveying applications (cm accuracy). This study shows that in surveying applications requiring centimetre accuracy, the RTK GPS/Galileo method can replace other survey methods (Total Station).

2

Impact of alien tree species Quercus rubra L. on understorey habitat and flora: a study of the Silesian Upland (Southern Poland)

Chmura D.

Polish Journal of Ecology

|

2013

|

Vol. 61, nr 3

431--442

EN

One hundred and one stands of non-native red oak Quercus rubra L. were examined across various forest types with the objective to relate the influence of environmental variables on the abundance of this species and to characterise its impact on the species richness and proportion of functional groups of native plant species. Amongst randomly selected stands more than 50% were self-regenerating ones, i.e. seedlings were present. The cover of Q. rubra seedlings was positively correlated with light intensity (rs = 0.38, P <0.05) and negatively with the content of nitrogen (rs = –0.20, P <0.05) and loss on ignition (rs = 0.20, P <0.05) in soil. The cover of mature trees was positively correlated with the value of pH (rs = 0.22, P <0.05). Separate correlations with DCA scores of phytosociological relevés and the cover of red oak in each layer showed that the species influenced the floristic composition of forest vegetation. The cover of mature trees of red oak negatively affected both the number of understorey species (rs = –0.39, P <0.01) and the cover of shrubs (rs = –0.21, P <0.05) and herbaceous species (rs = –0.22, P <0.05). Q. rubra in the form of a mature tree had a negative influence on the cover of barochores, endozoochores and species of Grime’s CSR strategy. The cover of red oak’s seedlings was negatively correlated with the cover of annual species (rs = –0.21, P <0.05). Saplings of Q. rubra had a negative influence on the cover of dyszoochores (rs = –0.21, P <0.05) and was positively correlated with competitors (rs = 0.31, P <0.01), megaphanerophytes (rs = 0.27, P <0.05) and therophytes (rs = 0.25, P <0.05). The study showed that Q. rubra is a competitive species both as a mature tree and in the form of seedlings or small saplings and thus it can contribute to the reduction of biodiversity in forest communities.

3

Charakterystyka śródleśnych oczek wodnych na terenie leśnego zakładu doświadczalnego Siemianice

Korytowski M.

Rocznik Ochrona Środowiska

|

2011

|

Tom 13

1847-1863

PL

W pracy przedstawiono wyniki badań przeprowadzonych w latach hydrologicznych 2002/2003 i 2007/2008 w zlewniach śródleśnych oczek wodnych nr 1, 3, 5 i 6, usytuowanych w leśnictwach Wielisławice i Laski na terenie Leśnego Zakładu Doświadczalnego Siemianice Uniwersytetu Przyrodniczego w Poznaniu (rys. 1). Lasy tych leśnictw leżą w zasięgu Niziny Południowo-Wielkopolskiej, na Wysoczyźnie Wieruszowskiej, będącej zdenudowaną równiną morenową przeciętą biegiem górnej Prosny [6]. Omawiane tereny leżą w zlewni Niesobu i Pomianki, które są lewobrzeżnymi dopływami Prosny. Przeważającym typem siedliskowym lasu, w zlewniach analizowanych oczek, jest las mieszany świeży (LMśw), który zajmuje około 95% powierzchni, a dominującym gatunkiem drzewostanu jest sosna w wieku około 95 lat. W omawianych zlewniach, w terenach położonych najbliżej badanych oczek, występują w przewadze gleby bielicowo-rdzawe, o uziarnieniu piasku gliniastego, z wkładkami utworów mocniejszych.

EN

The paper presents the results of the research carried out in 2002/2003 and 2007/2008 hydrological years. Hydrological year 2002/2003 was a middledry year in terms of rainfall - 56 mm lower than multi-year, when the air temperature was 1,0°C lower than multi-year average air temperature. The second analyzed year, 2007/2008 was a dry year - the rainfall total was 103 mm lower than multi-year and the air temperature was 0,8°C lower than average. The research was carried out in catchments of ponds No. 1, 3, 5 and 6, lo-cated in Wielisławice and Laski forestries - area of Siemianice Experimental Forest Farm of Poznan University of Life Sciences. The forests of mentioned forestries are within range of Południowo-Wielkopolska Lowland, on Wysoczyzna Wieruszowska, which is differential morainic plain, cut with the river Prosna headwaters. Discussed areas are located in catchment of Niesob and Pomianka rivers, which are left-bank tributaries of Prosna river. Fresh mixed forest is predominating in analyzed ponds' catchments - it takes about 95% of the area, and pine in age of ab. 95 years is predominating species of the tree stand. In areas situated closest to the ponds in analyzed catchments, there is a predominance of proper podzol soils with grain size of loamy sand. The ponds, discussed in this paper, have features typical for water reservoirs, from which essential are: the presence of water table, the presence of clearly outlined recess of the area, presence of vegetation affiliated with wet areas. The ponds No. 1 and 6, which have gentle slope, are typical natural melt ponds, ponds no. 3 and 5 are the results of human activities, as evidence by their unnatural shapes. The ponds No. 1 and 3 have no outflow. The pond No. 5 situated at the foot of morainic slope - is intensively supplied by spring waters from adjacent areas and it has constant outflow. According to the information from the local residents, the pond no 5 used to be a fish pond, and pond no. 6 in XIX century used to have an outflow through the ditch - today there's only left 60 m long section. Drainage occurred only at high states, mostly during the spring thaws. Currently discussed pond does not have any drainage, which is mainly attributable to the incidence of lower water levels and silting of the ditch. Two wetlands having their own microcatchments, located in south-eastern and eastern part of the catchment, has an important role in the water management of pond's no 6 catchment. Results of the research confirm that in most of analyzed ponds meteorological conditions (precipitation and air temperature) had a significant impact on the change of the water level. The only exception was pond no. 5, where the changes of the water level were caused by intensive supply by the spring waters. Studies have also shown that an important element in the characteristics of forest ponds, in addition to their morphometric features, is the variability of water levels in these ponds. A key determinant of changes in water levels in analyzed ponds, was the course of meteorological conditions, as well as the nature and size. In the research period most variable were ponds no. 1 and 3, characterized by small size and outflow, and the smallest variability had pond no. 5, supplied by the spring waters. Basing on the results of research and analysis it was also found, that in ponds of small size and with no outflow, with the highest variability of water levels, water table may disappear completely. Disappearance of the water table falls in these ponds mostly during the summer half-years.

4

Land snails as indicators of soil humidity in Danubian woodland (SW Slovakia)

Cejka T., Hamerlik L.

Polish Journal of Ecology

|

2009

|

Vol. 57, nr 4

741-747

EN

Moisture along with available calcium content are the major environmental factors controlling species richness and composition of the terrestrial molluscan fauna. In the present study, we focused on snails in a floodplain forest and their response on humidity. We described the model of response and calculate the humidity optima of particular species if possible. Generalised linear model (GLM) combined with Poisson distribution was used to ch aracterise the change of species abundance along a humidity gradient. From 31 species tested, 21 have shown significant response to humidity. The majority of specie s tested had unimodal response, four species showed monotonic regression type. Based on their humidity optima, species distributed along a moisture gradient belonged to three main ecological groups: (i) mesohygrophilous woodland species living mostly in non-inundated areas with humidity optima below 4, (ii) hygrophilous, forest hygrophilous and euryhygric species with optima between 4 and 6 and (iii) strongly hygrophilous (polyhygrophilous) species with mois ture optima above 6. Estimated moisture preferences for Danubian floodplain woodland land snail fauna would be a useful tool in a longterm biological monitoring of changing moisture regime.

5

Ocena technologii zrywki drewna ciągnikiem Timberjack 1010

Dobek T., Kochański R.

Inżynieria Rolnicza

|

2003

|

R. 7, nr 10

237--245

PL

W artykule przedstawiono wstępną ocenę technologii zrywki drewna ciągnikiem zrywkowym Timberjack 1010. Ocena zrywki została oparta na wskaźnikach eksploatacyjnych obliczonych na podstawie pełnego chronometrażu czasu pracy mierzonego od momentu przystąpienia operatora do maszyny do chwili jej opuszczenia w miejscu stacjonowania. Średnie wartości badanych parametrów pracy forwardera przedstawiają się w sposób następujący: prędkości jazdy bez ładunku 2,16 m/s, prędkość jazdy z ładunkiem 1,70 m/s, prędkość załadunku 0,88 m3/min, prędkość wyładunku 1,57 m3/min, wydajność efektywna 120,01 m3/h, wydajność operacyjna 25,77 m3/h; wydajność eksploatacyjna 19,13 m3/h (I dzień badań) oraz 18,55 m3/h (II dzień badań).

EN

The paper presents a preliminary evaluation of tree pulling out technology with a forwarder Timberjack 1010. The pulling out evaluation was based upon the usage ratios calculated on the basis of full working time measurement measured from the moment of the operator's approaching the machine to the moment of leaving it in the parking location. The average values of researched parameters of the forwarder work are as follows: driving speed without the load 2.16 m/s, driving speed with the load 1.70 m/s, loading speed 0.88 m3/min, unloading speed 1.57 m3/min, actual efficiency 120.01 m3/h, operating efficiency 25.77 m3/h; usage efficiency 19.13 m3/h (1st research day) and 18,55 m3/h (2nd research day).

6

Produkty leśne - podaż i popyt

Serrano O., Żubrzak M

Przegląd Papierniczy

|

1999

|

R. 55, nr 12

788--794