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The formation of the stand structure interacts with the processes of growth and competition. Previous observations mainly focused on the analysis of the type of tree distribution resulting from these processes. Development of spatial diversity of tree parameters is less known issue. The research was carried out in mountain Norway spruce stands with a large variety of taxation parameters located in the Beskid Żywiecki Mts. (southern Poland). The analysis of spatial autocorrelation of biometric features was carried out with the use of the mark correlation function, and the type of tree distribution was examined using the pair correlation function. In younger, less tended stands of high tree density, a stronger spatial autocorrelation of the tree biometric features was found. The strongest autocorrelation was observed for volume, weaker for the breast height diameter, while the weakest one was reported for height. The analysis indicated that density dependent competition affects the autocorrelation of biometric features more strongly than the type of tree distribution. The range of the tree perception zone determined on the basis of the autocorrelation analysis of features is greater or equal to the width of the inhibition zone determined on the basis of the point pattern type analysis.
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Timber hauling from the forest, either directly to the consumer or to the place of transshipment for a rail transport, is carried out by vehicles adapted to the transport of long or short logs and medium−sized wood. In Poland, regulations restrict the total weight of a vehicle traveling on roads, which consists of the weight of the empty vehicle and the weight of the load. When transporting the wood, the variability of the species, assortments, and wood moisture content does not allow for the unambiguous determination of the weight of transported timber, which often contributes to the excessive gross vehicle weight (GVW). In the conducted study, we analyzed Scots pine wood shipments (mainly short logs of length of 3.7−5.0 m) in different seasons of the year: in January (652 shipments), in March/April (1586), in July/August (1324), and in October/November (1914). GVW was calculated, based on the weight of an empty set and a weight of the load. The weight of the load was determined in two ways. In the first one it was calculated as a difference between loaded and unloaded truck. Measurements were carried out on the stationary scales. In the other method the volume of transported wood was taken from a delivery note and multiplied by the conversion rate for Scots pine, which equals 0.74 Mg/m³. The difference between both calculation methods reached 17%. It was found that in 2016 timber loads varied greatly, ranging from 41.3 to 66.9 Mg. The average GVW for the year 2016 was 50.64 Mg and it was on the similar level as in 2009 – 51.12 Mg on average, ranging from 40.06 to 64.20 Mg.
Paper discusses the influence of site quality on self−thinning process in silver birch stands growing on abandoned farmlands in Mazowieckie region (central Poland). Number of trees in a stand decreases with increasing age. The better the site (the higher site index value), the higher number of trees can be observed. However at the age of 10 difference between sites of various quality (site index) become insignificant. There is no need to include site index into the self−thinning models for young silver birch stands.
The aim of the study was to demonstrate how the trophy quality of antlers of the red deer stags living in two large forest complexes in the Mazowsze region (central Poland) differs from those inhabiting other regions of the country. The study used the data describing the body and antlers weight of 272 stags shot in 2005−2014 in two large, separated from each other, forest complexes of Spała and Gostynin. The stags from both forest complexes do not differ from each other in body weight and antler forms. The average body weight of the stags at the age of 12 is approximately 120−140 kg. The characteristics of antler forms of the stags harvested by hunters may not reflect the actual state because of the use, in practice, of the selection criteria instead of random killing. The most frequently harvested antler forms of the selection stags in the age classes of 3−5 years and 6−8 years are regular eight−pointers and irregular twelve−pointers, respectively. However, the small sample size used and the specific rules of harvesting the older stags do not allow to characterize the antler forms of the stags older than 9 years. In the autumn−winter period, a decrease in the body weight of the rutting stags at the age of over 6 years, as well as of the young, 2−5−year−old, stags is observed. The loss in body weight in young stags is approximately 20%, while in older stags – 35%. The decrease in body weight in the autumn−winter period is not stable. The largest, representing nearly 50% of the total weight loss, was recorded after the rut. In the period between November and December even a slight increase in body weight was noted followed again by a decline by the end of the winter.
The article presents the results of the survey on the preferences of disabled people on wheelchairs for selected features of recreation in forests. The study was conducted in 2015, including a sample of 108 people over the age of 18 interviewed simultaneously in the Poland and Czech Republic (52 interviews in Poland, 56 in the Czech Republic). Respondents were questioned both at the premises of the activation organizations as well as activation by email. The questions in the survey were designed to determine the preferences of the respondents in terms of the frequency and duration of the rest in the forests, the size of forest users groups, the choice of means of transport and certain equipment of forest recreation management. The results show that there is quite a lot of differences between the preferences of respondents from both of the analyzed countries. The statistic differences relate mainly to the choice of the means of transport enabling the rest of the forest, the frequency of recreation visits in the forests and the scope of necessary recreational infrastructure in the forests. The results indicate also significant differences in the profile of the respondents. They were associated with the place of residence, time of moving on a wheelchair and the use of a particular type of wheelchair.
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