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Alien tree species, due to their longevity, manifest their invasive potential after several decades from introduction. For the high threat to biodiversity, there is a need to analyze the risk of introduction connected with numerous alien tree species introduced in the various forest ecosystems. We aimed to assess the productivity potential and effect of alien Carya ovata on understory vegetation. Our study was conducted in the oldest (122 years old) tree stand of C. ovata in Poland, located in the Czerniejewo Forest District (western Poland). We analyzed C. ovata tree stand features and vegetation traits within the forest community and compared with natural vegetation – oak−hornbeam forest. We found that C. ovata trees had lower dimensions and standing volume than oaks (Quercus robur and Q. petraea) growing in the neighborhood. We also did not find the impact of C. ovata stands on understory vegetation species composition and light availability. Because of the low impact on forest floor vegetation and lack of spread we concluded that C. ovata cannot be classified as an invasive species. Moreover, its introduction was not successful in terms of tree stand productivity.
The aim of studies established in 1994 was evaluation of persistency of Trifolium repens and Lolium perenne in pasture sward under drier and postboggy habitat. Seed mixtures contained 50% of white clover and 30% of perennial ryegrass. Nitrogen fertilisation was differentiated in dependency on soil type: 90 kg on black soil And 45 kg ha⁻¹ year⁻¹. Content of white clover and perennial ryegrass in the sward depended on type and moisture of soil and sequence of regrowth in pasture season. Two first years of studies were very dry and then better white clover development was observed in wetter habitat. Among two white clover cultivars Rema proved to be more suitable on moister organic soils whereas Lithuanian cultivar Bitunaj on drier mineral ones. Those cultivars showed higher stability in the sward during the grazing season in more suitable habitats for them. Fast growing Lolium perenne was a dominant species in the harvest year, particularly on black soil, even during very dry vegetative season. Low tolerance to frost was the main reason of decrease of that species content in the pasture sward on both soils after 1995-1996 winter. In dry 1996 year there was observed better regeneration of ryegrass under postboggy habitat. During wetter following years ryegrass became again the dominant species on black soil. Presence of Trifolium repens in the pasture sward affected beneficially development and maintenance of Lolium perenne, especially in drier habitat. Floristic biodiversity of plant communities on peat-muck soils is rather low therefore introduction and maintenance of white clover and perennial ryegrass in pasture sward is needed to avoid Poa sp. and Festuca rubra expansion.
The aim of the study was to investigate the pattern of daily activity and connections between daily and spatial activity in relation to the forest undergrowth phytocenosis of the two most common rodent species – bank vole Myodes (Clethrionomys) glareolus (Cricetidae) and yellow−necked mouse Apodemus flavicollis (Muridae). The research was carried out in July 2017 in the oak−hornbeam habitat in the Browsk Forest District in the northern part of the Białowieża Forest. For rodents catching and vegetation evaluation the 1 ha study plot was divided into 100 squares of 10×10 m. Catches were made according to the catch−mark−release method. Wooden live traps (with bait and food for caught animals in the form of the grains of cereals, juicy fruits and aromatic fat) were set in the center of each square. The traps were controlled during 4 days at 3−hour intervals (0 a.m., 3 a.m., 6 a.m., 9 a.m., 12 p.m., 3 p.m., 6 p.m. and 9 p.m.). Traps occupied by rodents were marked with colored adhesive cards according to the established code. Twice a day – at 6 a.m. and 6 p.m. caught rodents were identified to the species and released next to the traps. The catch time was recorded. In total, 151 catches were registered. The daily activity of rodents was determined based on the total catches into assumed time intervals and at different times of the day (day, night, dawn/twilight). We provided a detailed description of undergrowth features of the area where rodents were caught. In each square we assessed the dominant species (on this basis the plants communities were established), the average height of vegetation and the degree of soil coverage with plants (undergrowth density). Collected data were used to the interpretation of the spatial activity of rodents in relation to the different undergrowth characteristics. The bank vole was distinguished by an even, day−and−night activity rhythm, while the yellow−necked mouse by monophasic – remarkably nocturnal activity. The dependence of the phytocenosis characteristics and spatial distribution of rodents was revealed for the daily activity of bank vole and twilight−dawn activity of both species. At dawn and dusk voles and mice were active in places with high vegetation. The density of undergrowth was the most important feature for bank voles during the day.
Na podstawie badań przeprowadzonych w 51 parkach wiejskich w stylu krajobrazowym (XVIII i XIX w.) o minimalnej powierzchni 2 ha, leżących w Kotlinie Sandomierskiej na siedliskach grądów (Tilio-Carpinetum) odmiany małopolskiej, określono zróżnicowanie florystyczno-fitosocjologiczne warstwy ziół. Parki wiejskie podzielono ze względu na dwie zmienne: pielęgnację (rozumianą jako koszenie warstwy ziół) i wielkość powierzchni danego obiektu. Wyniki badań wykazały, że obie zmienne mają wpływ na skład gatunkowy roślin w warstwie ziół. Procent pokrycia gatunków roślin z klasy Querco-Fagetea w warstwie ziół w niepielęgnowanych parkach wiejskich o dużej powierzchni oraz w naturalnych zbiorowiskach leśnych grądowych (Tilio-Carpinetum) jest większy niż w parkach pielęgnowanych.
Artykuł stanowi głos w dyskusji na temat inwentaryzacji siedlisk przyrodniczych podjętej przez Lasy Państwowe w 2006 roku. Rozważane są głównie dwa aspekty: identyfikacji niektórych typów siedlisk (i zbiorowisk) leśnych w procesie inwentaryzacji oraz sygnalizowanych przez przyrodników, potrzeb uzupełnienia listy siedlisk chronionych. Pełna diagnoza siedliska powinna obejmować zarówno rozpoznanie fitosocjologiczne jak i ocenę stopnia naturalności siedliska. Zdaniem autorów lista siedlisk chronionych winna być uzupełniona o ols porzeczkowy Ribeso nigri-Alnetum, ols torfowcowy Sphagno squarrosi-Alnetum oraz łozowisko Salicetum pentandro-cinereae.
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