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This paper presents the results of studies on the influence of soil preparation methods and ways of utilization of logging residues on belowground biomass of 3-year-old Scots pine saplings, after artificial regeneration. Statistically significant correlations were detected between root biomass and soil preparation methods, while there was no significant impact of logging residues management. Furthermore, interaction of methods of soil preparation and various ways of logging residues management also did not affect the belowground biomass of the plants. The greatest biomass was detected on the area where the soil was prepared by ploughing furrows with the LPz-75 plough. On plots where the soil was prepared by scarifying with rotary tiller, the lowest values of belowground biomass were observed.
W badaniach podjęto próbę ustalenia wpływu metod przygotowania gleby oraz sposobów utylizacji pozostałości zrębowych na kształtowanie się wielkości biomasy części nadziemnej sadzonek 3-letniej uprawy sosnowej, pochodzącej z odnowienia sztucznego. Przeprowadzone analizy statystyczne wyników dowiodły, że istnieje silny wpływ metod przygotowania gleby na wielkość biomasy. W przypadku sposobów utylizacji pozostałości zrębowych różnice pomiędzy wartościami biomasy części nadziemnej sadzonek na poletkach doświadczalnych okazały się statystycznie nieistotne. Na badany czynnik nie miała także istotnego wpływu interakcja metod przygotowania gleby i sposobów utylizacji pozostałości zrębowych. Największe wartości biomasy części nadziemnej odnotowano na powierzchniach, gdzie zastosowano orkę pługiem LPZ-75 oraz naoranie wałków, niezależnie od sposobu utylizacji pozostałości zrębowych. Z kolei na działkach, gdzie glebę spulchniono frezem leśnym stwierdzono najmniejsze wartości biomasy we wszystkich sposobach utylizacji pozostałości zrębowych.
The authors have studied the effect of an addition of calcium chloride to milk prior to its pasteurization on the molecular weight of proteins, their electrophoretic mobility, hydration of casein micelles, titration curves of isolated proteins and the coagulation of milk by rennet. The addition of calcium chloride enabled to increase the yield of hard and cottage cheeses. The products obtained contained protein of a higher biological value.
The aim of this study was to determine the influence of soil preparation on height of 3-year-old Scots pine plantation. Three methods of cutting residues management and three methods of soil preparation were analysed. Height structure was determined and mean heights in specific variants were statistically analysed. Conducted analysis showed, that the influence of soil preparation method was much greater than cutting residues management. Statistically significant impact on tree height was found in case of scarifying and mixing of topsoil with rotary tiller, where greatest mean height was observed. Ploughing furrows with LPz-75 plough proved to be the most beneficial method of soil preparation. In this case the greatest heights of 3-year-old Scots pines were measured.
The purpose of the research was to assess the possibility to compensate for the volume and its 10−year increase lost on future crop and trainer trees removed from the strip−roads by the increased growth of trees at their edge. The assessment comprised the estimation of the compensation period length and its percentage value 10 years after cutting the strip−roads. The analysis also comprised 5−year−long wood volume growth periods. The research was conducted in Scots pine stand, located in the eastern part in the Notecka Forest, the area managed by the Oborniki Forest District (western Poland). The strip−roads 2.5 m and 3.5 m of width were cut every 30 m in the 31−years−old stand. The measurements covered trees growing directly at the strip−roads as well as 2−4 m and 8−10 m away from them. The volume increase was calculated on the basis of tree− ring widths, on the cross−sections cut from the mid−points of 2−meter−long sections. The simulation of the possibility to compensate for the volume loss on future crop and trainer trees removed from strip−roads was conducted by calculating the difference of the average annual volume increments in a 10−year−long period for single trees from the 0−1 and 8−10 m zones, and for the sum of differences in annual increments between these zones as well as between the 2−4 m and 8−10 m zones. The results showed that the trees growing directly at the strip−roads had the largest periodic volume increments, and in case of the wider strip−roads the largest volume increments were also found on trees growing in the 2−4 m zone away from the strip−road. Simulations of the volume loss compensation period length and of 10−year volume increment showed that the compensation was possible in the variants with the wider strip−roads. 10 years after cutting the strip−roads, the compensation for the volume loss and for the lost 10−year volume increment, resulting from the increased increment on trees form the 0−1 m and 2−4 m, was 30% and 14%, in tree stands with wider and narrower strip−roads respectively.
This paper presents the results of studies on the influence of clear-cut site management on survival rate of 3-year-old Scots pine saplings, conducted in the Forest District Bierzwnik in September 2011. Statistical analysis showed, that only the soil cultivation method significantly influences the survival rate on the studied Scots pine plantation. No statistically significant influence of cutting residues management or combined methods of residues management and various variants of soil cultivation was found.
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