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The interplay between forest management practices, genetic monitoring, and other long-term monitoring systems
Darius Kavaliauskas, Barbara Fussi, Marjana Westergren, Filipos Aravanopoulos, Domen Finžgar, Roland Baier, Paraskevi Alizoti, Gregor Božič, Evangelia V. Avramidou, Monika Konnert, Hojka Kraigher, 2018, pregledni znanstveni članek

Povzetek: The conservation and sustainable use of forests and forest genetic resources (FGR) is a challenging task for scientists and foresters. Forest management practices can affect diversity on various levels: genetic, species, and ecosystem. Understanding past natural disturbance dynamics and their level of dependence on human disturbances and management practices is essential for the conservation and management of FGR, especially in the light of climate change. In this review, forest management practices and their impact on genetic composition are reviewed, synthesized, and interpreted in the light of existing national and international forest monitoring schemes and concepts from various European projects. There is a clear need and mandate for forest genetic monitoring (FGM), while the requirements thereof lack complementarity with existing forest monitoring. Due to certain obstacles (e.g., the lack of unified FGM implementation procedures across the countries, high implementation costs, large number of indicators and verifiers for FGM proposed in the past), merging FGM with existing forest monitoring is complicated. Nevertheless, FGM is of paramount importance for forestry and the natural environment in the future, regardless of the presence or existence of other monitoring systems, as it provides information no other monitoring system can yield. FGM can provide information related to adaptive and neutral genetic diversity changes over time, on a species and/or on a population basis and can serve as an early warning system for the detection of potentially harmful changes of forest adaptability. In addition, FGM offers knowledge on the adaptive potential of forests under the changing environment, which is important for the long-term conservation of FGR
Ključne besede: forest monitoring, forest genetic monitoring, forest genetic diversity, silviculture
Objavljeno v DiRROS: 20.02.2020; Ogledov: 2041; Prenosov: 1285
.pdf Celotno besedilo (766,78 KB)
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Evaluating WorldClim version 1 (1961-1990) as the baseline for sustainable use of forest and environmental resources in a changing climate
Maurizio Marchi, Iztok Sinjur, Michele Bozzano, Marjana Westergren, 2019, izvirni znanstveni članek

Povzetek: WorldClim version 1 is a high-resolution, global climate gridded dataset covering 1961-1990; a ˝normal˝ climate. It has been widely used for ecological studies thanks to its free availability and global coverage. This study aims to evaluate the quality of WorldClim data by quantifying any discrepancies by comparison with an independent dataset of measured temperature and precipitation records across Europe. BIO1 (mean annual temperature, MAT) and BIO12 (mean total annual precipitation, MAP) were used as proxies to evaluate the spatial accuracy of the WorldClim grids. While good representativeness was detected for MAT, the study demonstrated a bias with respect to MAP. The average difference between WorldClim predictions and climate observations was around +0.2 °C for MAT and -48.7 mm for MAP, with large variability. The regression analysis revealed a good correlation and adequate proportion of explained variance for MAT (adjusted R2 = 0.856) but results for MAP were poor, with just 64% of the variance explained (adjusted R2 = 0.642). Moreover no spatial structure was found across Europe, nor any statistical relationship with elevation, latitude, or longitude, the environmental predictors used to generate climate surfaces. A detectable spatial autocorrelation was only detectable for the two most thoroughly sampled countries (Germany and Sweden). Although further adjustments might be evaluated by means of geostatistical methods (i.e., kriging), the huge environmental variability of the European environment deeply stressed the WorldClim database. Overall, these results show the importance of an adequate spatial structure of meteorological stations as fundamental to improve the reliability of climate surfaces and derived products of the research (i.e., statistical models, future projections).
Ključne besede: spatial analysis, spatial interpolation, geostatistics, ecological mathematics
Objavljeno v DiRROS: 20.02.2020; Ogledov: 1754; Prenosov: 1057
.pdf Celotno besedilo (2,62 MB)
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Genetic diversity of core vs. peripheral Norway spruce native populations at a local scale in Slovenia
Marjana Westergren, Gregor Božič, Hojka Kraigher, izvirni znanstveni članek

Povzetek: We investigated the levels of genetic diversity and population differentiation among core and peripheral populations of Norway spruce along an altitudinal gradient (from inversions to upper tree line) using isoenzymes (ISO) and nuclear simple-sequence repeats (SSR) markers on overlapping set of populations. Twenty-seven to seventy trees from 11 and 7 populations were genotyped with isoenzymes and SSRs, respectively. The results partially conform to the expectations of the central-peripheral hypothesis (CPH) and are consistent for both marker sets. Genetic differentiation among peripheral populations was low but significantly different from zero (FST-ISO = 0.013, FST-SSR = 0.009) and higher than that among core populations (FST-ISO = 0.007, FST-SSR = 0.005), conforming to central peripheral hypothesis. Contrastingly, levels of genetic diversity assessed by both richness and equitability measures did not significantly differ between peripheral and core populations (AR-ISO = 2.20 vs. 2.14, AR-SSR = 17.16 vs. 17.68, HE-ISO = 0.183 vs. 0.185, and HE-SSR = 0.935 vs. 0.935 for peripheral and core populations, respectively).
Ključne besede: central peripheral hypothesis, Picea abies (L.) Karst., genetic diversity, genetic differentiation, upper tree line, inversion
Objavljeno v DiRROS: 07.05.2018; Ogledov: 8032; Prenosov: 1760
.pdf Celotno besedilo (561,16 KB)
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Identifikacija izvora gozdnega reprodukcijskega materiala bukve s pomočjo molekularnih metod
Marjana Westergren, Marko Bajc, Domen Finžgar, Gregor Božič, Hojka Kraigher, 2017, izvirni znanstveni članek

Povzetek: Od kakovosti in izvora gozdnega reprodukcijskega materiala (GRM) bodo odvisni genetska pestrost, struktura, preživetje in uspevanje sadik ter končno uspevanje in odpornost bodočega gozda. Zato mora Gozdarski inštitut Slovenije (GIS) na podlagi javnega pooblastila po Zakonu o gozdovih in zahtev zakonodaje o GRM preveriti njegov izvor pred izdajo glavnega spričevala ali na zahtevo inšpektorata kadarkoli v času trženja in uporabe. Uporaba molekularnih metod pripomore k vedenju o izvoru in genetski kakovosti GRM. GIS kontinuirano razvija znanje, infrastrukturo, gensko banko in molekularne baze podatkov za izvajanje opisanih testov. Zaradi suma o (načrtno) napačni navedbi izvora GRM, nabranega jeseni 2016 iz vsaj enega semenskega objekta, smo v predstavljeni študiji analizirali izvor in genetsko pestrost GRM iz štirih semenskih objektov bukve (Fagus sylvatica L.), v katerih je bilo seme nabrano v istem letu, ter drugih vzorcev iz Slovenske gozdne genske banke, skupaj petnajst. Za analize smo uporabili jedrne mikrosatelite, šestnajst lokusov, ki jih na GIS uporabljamo rutinsko. S tehničnega vidika so se izbrani markerji izkazali za primerne za identifikacijo posameznikov, oceno genetske pestrosti in identifikacijo domnevnega izvora. Zaradi možnosti mešanja vzorcev, pridobljenih s tal, in tehničnih potreb bomo v prihodnosti za potrebe rekonstrukcije genotipa semenskega drevesa analizirali vsaj dvanajst semen na drevo. Genetska pestrost manjših vzorcev je bila značilno manjša od tiste v velikih vzorcih. Opozarjamo, da je GRM nujno treba nabirati najmanj z v odobritvi semenskega objekta predpisanega števila dreves, da zagotovimo ustrezno veliko genetsko pestrost GRM, ki ga sadimo v gozdove. Metode razvrščanja posameznikov na podlagi Bayesove verjetnosti in filogenetska drevesa so pravilno določili izvor referenčnih vzorcev, medtem ko je bila resolucija analize glavnih komponent manjša. Vse metode, uporabljene za identifikacijo domnevnega izvora vzorcev semena, so nedvoumno pokazale, da vzorec TURs ni bil nabran v sestoju TUR, različen je tudi od preostalega analiziranega genofonda bukve v Sloveniji.
Ključne besede: Fagus sylvatica, gozdni reprodukcijski material, identifikacija izvora, genetska pestrost, mikrosateliti, analiza starševstva, Slovenija
Objavljeno v DiRROS: 03.09.2017; Ogledov: 4003; Prenosov: 735
.pdf Celotno besedilo (512,44 KB)

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