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Ključne besede: gozdno-lesni sektor, gozdni lesni sortimenti, okrogli les, politični ukrepi, trg lesa, proizvodnja, zunanja trgovina, lesni proizvodi, napovedi tokov lesa, tokovi lesa, les za energetske namene
Objavljeno v DiRROS: 05.01.2024; Ogledov: 207; Prenosov: 58
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Povzetek: Fertilisation is often used to increase plant productivity in agriculture but has also been used in forestry. In our study, Scots pine forest growing in a nitrogen-poor environment was fertilised with NPK post-production wastewater from a potato starch factory. Our research aimed to investigate the dependence of tree growth on different NPK concentrations. Cell characteristics such as cell wall thickness (CWT), lumen diameter (LD) and tree-ring features such as ring width (RW), total number of cells in annual growth (nTotal), earlywood (EW) and latewood (LW) were investigated. Twenty-six years of regular fertilisation of the forest with different doses of wastewater rich in NPK elements have affected the anatomical structure of Scots pine trees. It is presumed that the reduction in CWT and LD on the fertilised site was due to deficiencies in plant water conductivity, which may have occurred due to physiological drought. The influence of nitrogen on unfertilised site from the wastewater area could contribute to the CWT thickening. The results confirm that the use of NPK in excessive doses is detrimental to trees' conductive system.
Ključne besede: wastewater effluents, forest fertilisation, cell measurements, tree-ring width, wood anatomy
Objavljeno v DiRROS: 03.01.2024; Ogledov: 237; Prenosov: 132
Celotno besedilo (4,94 MB)
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Ključne besede: varstvo gozdov, morfološke analize, Ips duplicatus, dvojnozobi smrekov lubadar
Objavljeno v DiRROS: 19.12.2023; Ogledov: 207; Prenosov: 0

Ključne besede: protipožarna infrastruktura, protipožarne prometnice, protipožarne preseke, gozdne prometnice
Objavljeno v DiRROS: 15.12.2023; Ogledov: 270; Prenosov: 57
Celotno besedilo (2,05 MB)

Povzetek: Local survival of forest tree populations under climate change depends on existing genetic variation and their adaptability to changing environments. Responses to selection were studied in European beech (Fagus sylvatica) under field conditions. A total of 1087 adult trees, seeds, 1-year-old seedlings and established multiyear saplings were genotyped with 16 nuSSRs. Adult trees were assessed for phenotypic traits related to growth, phenology and reproduction. Parentage and paternity analyses were used to estimate effective female and male fecundity as a proxy of fitness and showed that few parents contributed to successful regeneration. Selection gradients were estimated from the relationship between traits and fecundity, while heritability and evolvability were estimated using mixed models and the breeder's equation. Larger trees bearing more fruit and early male flowering had higher total fecundity, while trees with longer growth season had lower total fecundity (directional selection). Stabilizing selection on spring phenology was found for female fecundity, highlighting the role of late frosts as a selection driver. Selection gradients for other traits varied between measurement years and the offspring cohort used to estimate parental fecundity. Compared to other studies in natural populations, we found low to moderate heritability and evolvability for most traits. Response to selection was higher for growth than for budburst, leaf senescence or reproduction traits, reflecting more consistent selection gradients across years and sex functions, and higher phenotypic variability in the population. Our study provides empirical evidence suggesting that populations of long-lived organisms such as forest trees can adapt locally, even at short-time scales.
Ključne besede: climate change, Fagus sylvatica, heritability, in situ adaptation, response to selection, selection gradients
Objavljeno v DiRROS: 12.12.2023; Ogledov: 216; Prenosov: 101
Celotno besedilo (6,82 MB)
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