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The study aimed to determine the influence of site moisture conditions on the health status of European ash. The research plots were located in the Babki, Konstantynowo and Łopuchówko forest districts, as well as in the Poznań Municipal Forests (western Poland). The research was carried out on 30 research plots established in the part of the stands with at least 80% share of ash in the stand species composition. Ash aged from 48 to 144 years. The scope of the research included: (1) selection of the research plots and determination of the forest site type, (2) assessment of site moisture conditions – the type and degree of moisture and the depth of the groundwater level, (3) selection of 15 trees belonging to the 1st and 2nd Kraft’s class and assessment of their health status using the synthetic damage indicator, which is based on the crown defoliation and vitality of upper part of the crown. Results revealed that the best health status of ash stands was noted in mesic broadleaved forest. In contrast, within the stands in moist broadleaved forest, alder−ash forest and riparian forest we observed the highest share of damaged and dying trees. The more detailed analysis of moisture conditions showed that the lowest damage of ash was noted within the stands with the groundwater level at depth below 1.8 m and up to 0.5 m. Moreover, a high share of healthy and weakened trees occurred also within the stands with water flowing down the slope and in the compact soils, where water does not undergo significant level fluctuations. The most damaged stands occurred mostly in dehydrated soils, as well as in the soils where the depth of the groundwater was between 0.5 and 1.8 m.
The paper presents a method of Landsat 5 Thematic Mapper satellite image processing to assess the condition of forests in the Tatra National Park (southern Poland). Selected images were acquired on 1987/09/01, 2005/09/02 and 2011/09/03 from the same sensor with maximum time interval for the first and last scene and from similar phenological period. Firstly, the data were radiometrically corrected using the ATCOR 2/3 software and Digital Terrain Model from the ASTER mission. Quality of the correction was assessed calculating RMSE for reflectance values from images and resampled spectral characteristics collected in terrain. RMSE was in range 3−10%. Next, basing on Landsat images, Normalized Difference Infrared Index (NDII) and a Maximum Likelihood supervised classificatory, following dominant land cover types were identified: forests (including dwarf pine), grasslands, rocks, lakes, shadows (additionally clouds were distinguished on data from 1987/09/01). It allowed to select forest areas with producer accuracy not worse than 97.69% and user accuracy not worse than 98.31%. On corrected Landsat images Normalized Difference Vegetation Index (NDVI, an overall vegetation state) and Moisture Stress Index (MSI, canopy water content) were calculated. Vegetation indices discriminated forest state using the decision tree method. The worst overall condition was observed for the 1987 (about 21% of forest stands were in the worst condition and 87% were in medium condition), while the best one in 2005 (75.51% forest stands were in good condition and 10.66% were in the best condition). In case of 2011, the overall condition was quite good, but there were large areas with poor condition caused by bark beetle outbreaks. Proposed method allows for a fast and objective assessment of forest condition. It is possible to detect damaged areas or stands in poor condition. It can be complement for traditional methods of monitoring and management in forestry and nature protection.
This paper addresses the issue of poor condition of trees in urban areas. The health condition of tree stand depends on many factors. Conditions prevailing in the city often do not provide for proper growth and development and allow only the vegetation of trees lasting several years after planting. Manifestations of tree health problems are usually visible lesions within the crown or trunk and are only effects of adverse factors on the root system. The most dangerous causes of ill health in trees are associated with intensity of the negative anthropopressure impact in the cities, affecting the changes in the soil environment. A thorough read of the processes occurring in the urban soils allowed presentation of the methods used to ensure adequate habitat conditions for trees in Europe and North America. Awareness of the need to use systems has increased in recent years in Poland. Attempts to use a variety of methods used worldwide and technologies used in the Polish cities allow to analyse the systems in terms of their effectiveness as well as potential barriers and opportunities for their implementation. The aim of the research is to designate the systems with long-term beneficial effects on the trees, the use of which would have impact on life extension of the trees in Polish cities.
The thesis presents comparative analysis of two methods of trees valuation. The first one is the current administrative system used to determine the level of fees and penalties charged for trees removal. Detailed description of this method for calculating the fees and penalties is included in the Regulation of the Minister of Environment dated October 13, 2004. Administrative fees do not take into account significant factors affecting the assessment of the value of trees. The second method, developed by the Institute of Spatial Planning and Housing (IGPiM) in collaboration with the University of Life Sciences (SGGW), defines the trees replacement value as based on the series of evaluation elements applied widely in the methods used globally. This second method allows for a more realistic assessment of the value of trees, as it takes into account costs of tree production in the nursery and factors relating to older tree’s condition and its location.
Existing historical parks are often all that remains of important prestigious residences. Often converted as open public places, the old palace parks and estates have become a permanent feature in the landscape, being places of great cultural and natural value. One of the major components of such parks is the presence of old and in some cases ancient trees, especially valuable when it takes the character of a collection of plants with a high diversity of species and cultivars. Today, there is often a need for restoration work within these historical parks, often in modernising them or adapting them for new functions. Unfortunately, these actions are frequently undertaken incorrectly or irresponsibly, without taking into consideration the presence of valuable park trees. Changes in site conditions in the immediate vicinity of the trees may be the primary cause of deterioration in their health, manifested by a significant weakening and irreversible degradation. This applies especially to old specimens, whose adaptability to environmental changes is very limited. The aim of this study was to identify in selected examples, the relationship between the condition of park trees and improper execution of technical work in their vicinity related to the modernisation and maintenance of the park.
The article presents a significance of the evaluation of urban trees and benefits of ecosystem services gained from the presence of trees in cities. There was discussed a historical outline of implementing new methods of trees evaluation from cities of each continent and Poland, the country where already 40 years ago has been used a term „infrastructure” with a reference to the natural environment. It underlines also the importance of know-how development in monetary value of multiple utilities generated by trees when it comes to temperature regulation, carbon dioxide absorption, atmospheric air purification, reducing the flow of rain water and other benefits from shaping ecological education and stimulating grassroots initiatives in protecting and growing trees in urban areas. In the article were analyzed the differences between polish term „to make a charge” for removing trees and the term „trees evaluation” which is a tool used abroad to protect urban trees.
The roadside avenues in the open landscape of the Western Pomerania are a very characteristic element, deciding about its identity. Unfortunately in recent years due to the road modernization there has been lasting uncontrolled, simply mass cutting out of the roadside avenues. The grounds of taking action for the preservation of historical avenues is their valorization, based on standardized, synthetic methodology followed by the devising of the roadside avenues conservation programme. Methodology is based on an equivalent and comprehensive evaluation of the dendrological, ecological, landscape, composition and historical values of the avenues. In this paper the results of the valorization of eight roadside avenues were presented. Seven avenues in the whole and most valuable section of the avenue Maszewo-Jenikowo, were recommended for the conservatory protection, as work of the garden art with high cultural and landscape advantages. The effective mechanism allowing the protection of the most valuable westpomeranian avenues is getting started the procedure for putting them on the list of monuments. It is necessary to take an urgent valorization of all roadside avenues on the area of the Western Pomerania and the most valuable one should be taken under the conservatory protection, as a precious, natural or cultural objects.
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