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Badania miały na celu określenie wpływu gazowych i pyłowych zanieczyszczeń powietrza atmosferycznego na zawartość fluoru w glebach wybranych kompleksów leśnych położonych w strefie oddziaływania emisji przemysłowych. Próbki glebowe pobierano na powierzchniach badawczych zlokalizowanych w różnej odległości od źródeł emisji na obszarze Konińskiego Okręgu Przemysłowego. W glebach oznaczono zawartość fluoru rozpuszczalnego w wodzie (FH₂O) i fluoru uwalnianego kwasami (FH). Uzyskane wyniki pozwoliły stwierdzić wyraźną kumulację fluoru w poziomie ektopróchnicy (od 3,85 do 9,90 mg FH na 100 g gleby) oraz wyraźnie mniejszą koncentrację w poziomach mineralnych. W okresie badań następował stopniowy wzrost zawartości fluoru w glebach badanego rejonu. Stwierdzono również, że niezbędne zabiegi związane z odnowieniem powierzchni zrębowych sprzyjały migracji tego pierwiastka w głąb profilu glebowego. Zmiany ilościowe były uzależnione również od lokalizacji poszczególnych powierzchni badawczych.
The removal of trees from an area increases the minaralization and leaching processes in the upper layer of the soil. Different treatment methods were applied to logging residues affect those processes. As the investigation shows, the burning of branches enriches the soil in minerals, but the minerals are quickly leached down into deep soil layers. Taking the branches away from the clear cut area leads to an inreased mineralization of organic matter and enchances the leaching of minerals down into the soil. The variants in which branches and needles are left on the clear cut area, have different effects on chemical properties of the soils.
Forests play a very important role in the process of the carbon cycle in the natural environment and timber harvesting disturbs the natural circulation of this element considerably. Moreover, the way of handling the post clear cutting residues can also influence the accumulation of carbon in the soil. Usually, increased contents of organic carbon in the near-surface layers of mineral forest soils were observed in the first year following the stand removal. The greatest soil carbon enrichment was recorded when branches were ground and mixed with the mineral soil. Considerable variations in the observed contents of organic carbon in the near-surface layer of mineral soils during the first two years after clear cutting and later makes it impossible to indicate the most advantageous method of management of post clear cutting residues.
Effects of post−harvest wood−debris utilization and pre−planting soil preparation in clear−cut forest on the community structure of soil fungi and bacteria and their possible biological activity towards Armillaria and Heterobasidion were studied in 1− and 10−year−old Scots pine plantations in Bierzwnik and Międzychód Forest Districts (W Poland). Post−harvest wood−debris utilization included: (i) removal from the surface, (ii) spread of the coarse or chipped wood−debris on the surface and (iii) mixing of the chipped wood debris with the soil. Pre−planting soil preparation included: (i) deep furrowing, (ii) shallow turning of the topsoil, (iii) ridging and (iv) no ground preparation. The soil−dilution method was used for detection of fungi and bacteria in soil. Morphotyping was used for identification of fungi. Phenotypic traits and biochemical properties were used for identification of bacteria. Molecular method, MID−66 or BIOLOG® systems were additionally applied for identification of the most common bacteria. Removal of post−harvest wood−debris from the surface of the clear−cut land and shallow turning of the topsoil or ridging before planting increased abundance of fungi in soil of 1−year−old Scots pine plantation. Deep furrowing resulted in increased abundance of fungi and no ground preparation in increased abundance of bacteria in soil of 10−year−old Scots pine plantation. Increased abundance of fungi and bacteria was associated with increased abundance of taxa considered as antagonistic to Armillaria and Heterobasidion. Removal of the post−harvest wood debris and moderate or no mechanical intervention into the soil habitat on the clear−cut site before planting of Scots pine seedlings seems to create the habitat, which may be beneficial for the growth of young trees.
Effects of different pre-planting soil preparations and post-harvest wood debris applications in a clear-cut Scots pine plantation, on the abundance, diversity, and activity of culturable microorganisms were investigated. The investigation was done 9 years after the re-plantings had been done. This formed part of an investigation of silvicultural practices for conservation and the biological control of Armillaria and Heterobasidion in northern temperate forests (Poland). The treatments being compared, were expected to have altered the soil’s physical and chemical properties, and consequently, its biological properties. Only soft-rot microfungi from the Ascomycota and Zygomycota were detected in the soil. Fungi, including those antagonistic to Armillaria and Heterobasidion, were more abundant after shallow ploughing than after deep ploughing or ridging, and where chipped rather than coarse wood debris was left on the soil surface or incorporated. Scots pine trees had the most biomass and the least mortality after ridging and leaving coarse wood debris on the surface (associated with only a relatively moderate abundance of fungi).
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