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Determination of lime tree (Tilia begonifolia Stev.) stems form based on quantitative parameters (Study area: Shafaroud forests of Guilan province, Iran)

Abstract

The lime tree is one of the rare and valuable species that found in the Hyrcanian moist forests with economic as well as ecological value. Identification of the quantitative and qualitative features of this species is important. In order to investigate the stem form of this species in the Shafaroud forests of Guilan Province, 141 lime trees in 39 plots were analyzed during the four stages of small pole, pole, saw-timber, and maturity. In each plot, stem-diameter at different heights was measured by using the Spiegel Relaskop. Measurements and analyses included diameter at breast height( d.b.h.) and total height. Same parameters was calculated: stem form factor based on diameter, stem form factor based on volume, form quotient, slenderness factor, ratio of stem height to total height, ratio of stem volume to total volume, correlation, and coefficient of determination to describe stem form factor. The results showed that the average stem form factor based on diameter was 0.554. The average stem form factor based on volume was 0.576, average form quotient was 2.32 and slenderness factor was 35.04%. The average ratio of stem height to total height was 82.45. In addition the results indicated a strong relationship between diameter at breast height and trunk coefficient. The ratio of stem volume to total volume revealed that 64.44 of lime volume is located in the bottom half of the trunk. The value of the parameters described here is towards a better description of stand characteristics. Obtained results indicating stability for natural lime tree in Iran.

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Carbon Sequestration of Above-Ground Biomass of Pinus Sylvestris L. in the Green Belt of the City of Astana

Abstract

The article presents the results of research in the pine plantations located in the green belt of the city of Astana, the dry steppe zone of Northern Kazakhstan, and in the research, the data on biomass and carbon content in various fractions of Scots pine were obtained. Assessment of morphometric parameters of the pine stands was carried out by measuring tree height and trunk diameter at breast height (DBH); to determine the carbon content, laboratory analytical methods were used. Samples were taken from each element of biomass (branches, trunk, leaves, and bark) of Scots pine, in triplicate. After that, the green mass was weighed on the analytical scales to within 0.001 g. The samples were then dried to a constant weight at a temperature of 65°C. In laboratory samples without mineralization, the content of carbon was determined using element analyser. Regression equations were used to calculate the biomass of stocks. To measure the taxation indicators and sampling of plantations, trial plots were laid in triplicate for trial plots, the height of plantations varied on average from 5.8 m to 8.4 m on the plotted trial plots, and the diameter of the trunk varied from 7.7 cm to 8.8 cm. The correlation between plant height and stem diameter was 0.745. As the studies of chemical composition in needles, bark, trunk and branches of pine trees showed, the amount of carbon was from 50.03 to 51.33%. Thus, the study of the chemical composition of the pine plantations showed that the greatest content of chemical elements, such as carbon, was in tree needles. The accumulation plantations of Pinus sylvestris L. in the green belt of the city of Astana were sequestrated 973.3 tons of carbon in the above-ground biomass varied from 2.9 to 4.8 t/ha.

Open access
Genetic overload of silver fir (Abies alba Mill.) from five populations from central Bosnia and Herzegovina

Abstract

The research was conducted with a view to establishing physiological parameters of the silver fir (Abies alba Mill.) with regard to germination energy, absolute germination and genetic overload produced by silver fir populations. The intention was to identify significant variability within populations and subpopulations, or rather within the two combined, and to give recommendations on the usage and usability of seeds from specific populations.

The results form a basis for establishing silver fir genetic overload within five fir populations of central Bosnia and Herzegovina. The results of research on the characteristics such as absolute seed weight, germination energy and absolute germination are within a scope of previous studies.

The studied physiological characteristics of silver fir seeds in the central Bosnia area showed distinct individual and inter-population variability when compared to variability of the subpopulations analyzed.

The inclusion of non-physiological data (height, DBH, age and the presence of mistletoe) concerning sampled trees proved to be effective new quality of research. No correlation was found between DBH and seed physiological characteristics but increased tree height had a positive effect on seed quality in terms of absolute germination and growth, proportional to tree height. This in turn shows that seeds should be collected only from trees of above average height, because they are less genetically overloaded.

The characteristics of healthy but ungerminated seeds from less tall trees displayed lower parameter values, also indicating that seeds should be collected from taller than average trees only.

The presence of mistletoe had a very interesting effect of increasing rotten seeds percentage, and therefore reducing seed quality. Accordingly, seed collection should be limited to trees not affected by mistletoe, however further research on this aspect is required.

Open access
Proportion of knotty wood in stems of 28-year old lodgepole and Scots pine in experimental plantation in Zvirgzde, Latvia

Abstract

In forestry, alien tree species are planted to maximize yield from a stand by increasing productivity and decreasing environmental risks. In Eastern Europe, lodgepole pine (Pinus contorta var. latifolia) might be used as a source of biomass and industrial wood; however, before any recommendations are given, possible gains of the novel species should be scrupulously evaluated. In this study, we compared volume and proportion of knotty stemwood (VKN) of native Scots pine (Pinus sylvestris) from first generation seed orchards and provenances of alien lodgepole pine [Fort Nelson (58°38’ N, 122°41’ W) and Summit Lake (54°24› N, 122°37› W)] at the age of 27 years growing in central Latvia. We also assessed the relationships between VKN and several morphometric parameters.

Stem diameter of both species was similar; however, Summit Lake provenance of lodgepole pine exceeded Scots pine in height, while Fort Nelson provenance was lower than Scots pine. Although Scots pine produced nearly two times less whorls than lodgepole pine, volume of knotless stemwood did not differ significantly between the species; though it was higher for Summit Lake provenance of lodgepole pine compared to Scots pine. In contrast, the proportion of VKN differed significantly between both the species and the provenances. Scots pine showed the lowest proportion of VKN (~ 9%) and Fort Nelson provenances of lodgepole pine showed the highest proportion of VKN (~ 14%). Thus, Summit Lake appears more suitable for the production of industrial wood amongst the provenances of lodgepole pine; nevertheless, higher quantity of leftover material is expected. Some morphometric parameters correlated with VKN and the proportion of VKN, but these relationships differed between species and provenances. The total cross-section of branches was the best predictors of VKN for Scots pine and Fort Nelson provenance of lodgepole pine, while stem diameter showed the strongest correlation for Summit Lake provenance. Number of whorls and mean diameter of living branches were the best predictors of the proportion of VKN for lodgepole pine and Scots pine, respectively. Accordingly, morphometric parameters might be useful for the selection of the best trees of lodgepole pine.

Open access
Scots pine Pinus sylvestris mortality after surface fire in oligotrophic pine forest Peucedano-Pinetum in Kampinos National Park

Abstract

Pines are generally fire-resistant trees. There is a shortage of research on the behaviour of Scots pine after surface fire in older stands. The aim of the work was to describe the effect of the surface fire intensity on the mortality of pines of various diameter at breast height (DBH), including older trees. The research was conducted in Peucedano-Pinetum oligotrophic Scots-pine forest in Kampinos National Park (KPN, central Poland) on the area of two adjacent surface fire sites originated in spring 2015 in 60- to 200-year-old stands (site area: 10,92 ha). There were 45 (28 burned and 17 control) permanent plots established after the fire. The share of not burned, superficially burned and completely burnout organic horizon of the soil was determined within all of them. DBH and location of pine trees were measured within all of the plots on the area of 200 m2. For all of the trees for which full information about soil organic horizon damage was mapped, the prevailing type of disturbance in their close neighbourhoods with radii of 1 and 2 m was assessed. The mortality of trees was assessed after each vegetation period up to 2017, basing on the presence of green needles on the trees. The influence of fire intensity on the survival of trees was examined on whole permanent plot level as well as on individual tree level. Strong linear correlation was observed between Scots pine mortality and the share of plots area with damaged organic layer, especially at the end of the third vegetation period after fire. Logistic regression models constructed for individual trees suggest that bigger tree diameter (hence, thicker bark) diminished the odds of mortality only after two vegetation periods from the fire. After the third vegetation period, only the intensity of surface fire in the close neighbourhood of trees influenced (negatively) the chance on survival. The size of trees did no matter in this case. Nearly all of the trees that were located within burnout organic matter areas died. The results did not support the commonly known mechanism of enhancement of bigger Scots pine tree survival after surface fire because of thicker bark responsible for heat protection. Probably, the main cause of observed mortality was not overheating of cambium but it was rather connected to massive fine root loses. Scots pines growing on oligotrophic arid sites modify their root system to explore topsoil layers with higher proportion of shallow roots, growing even in organic litter layer. This corresponds with massive (regardless of size) pine mortality within sites characterised by complete burnout of organic matter layer and very high survival in those ones with only surfacely burned litter layer. The results can improve the assessment of surface fires consequences in managed Scots pine stands growing in oligotrophic conditions.

Open access
Sensitivity of vegetation indices in relation to parameters of Norway spruce stands

: http://www.blackbridge.com/ (Access: 19th Jun 2014). Weier J., Herring D. 2000. Measuring vegetation. Articleon-line: URL: http://earthobservatory.nasa.gov/Features/MeasuringVegetation/ (Access: 9th Oct 2014). Woźniak E. 2011. Analysis of correlation between vegetation and fire intensity indexes: the case of forest fires occurred in Greece in 2007. Teledetekcja Środowiska, 45, 19-24. Xiao Y., Zhao W., Zhou D., Gong H. 2014. Sensitivity analysis of vegetation reflectance to biochemical and biophysical variables at leaf

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Relationship between the content of chlorinated hydrocarbons and fatty acid composition of milk fat

-parametric Kruskal–Wallis test was applied (analysis at the level of significance of P ≤ 0.05) to calculate the significance of differences between the mean values. To investigate the relationship between chlorinated hydrocarbons content and fatty acids composition in milk fat, a correlation analysis was performed and Pearson’s correlation coefficients were calculated using correlation matrix modulus and Statistica 12.0 software (StatSoft Inc., Tulsa, Oklahoma, USA). Results The content of selected chlorinated hydrocarbons in cow and mare milk is presented in Table 1

Open access
Genetic Parameters of Conformation Traits in Young Polish Holstein-Friesian Bulls

leg traits in future AI bulls: II. Correlation to body conformation traits in daughter. Acta Agr. Scand. A-An., 51: 122-128. Lawstuen D., Hansen L., Johnson L. (1987). Inheritance and relationships of linear composite type traits for age groups of Holsteins. J. Dairy Sci., 70: 1027-1035. Meuwissen T.H.E., GoddardM.E. (1997). Optimization of progeny tests with prior information on young bulls. Livest. Prod. Sci., 52: 57-68. Misztal I. (2008). Reliable computing in estimation of variance components. J. Anim. Breed. Genet

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Genetic Parameters of First Lactation Milk Yield and Fertility Traits in Brown Swiss Cattle

.09.2010). Araújo C.V., DeTorres R., De A., Rennó F.P., Pereira J.C., Pereira C.S., Araújo S.I., Filho R., De A.T., Silva H.C., Rennó L.N., Kaiser F., Da R. (2003). Genetic trend in productive traits to Brown Swiss breed. R. Bras. Zootec., 32 (Supl. 2): 1872–1877. Atil H., Khattab S.A., Yakupoğlu C. (2001). Genetic analysis for milk traits in different herds of Holstein Friesian cattle in Turkey. On Line J. Biol. Sci., 1: 737–741. Bagnicka E., Distl O., Harmann H., Lukaszewicz M. (2004). Heritabilities of and genetic correlations between the dairy traits in goats estimated in

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Relationships Between Performance Test Results of Gilts of Different Breeds

References Bobček B., Řeháček P., Flak P., Kováč L., Mlynek J. (2002). Comparison of production traits of Large White and White Meaty pig breeds for 1996 to 2001 in Slovakia. Czech J. Anim. Sci., 47 (11): 451-459. Buczyński J.T., Fajfer E., Panek A., Szulc K. (2001). Correlations between fattening and slaughter traits measured live after the first and second phase of rearing Polish Large White breeding gilts. Ann. Anim. Sci., Suppl., 1: 31-36. Cameron N.D., Curran M.K. (1995

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