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Iskalni niz: "avtor" (Lado Kutnar) .

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61.
Effects of various cutting treatments and topographic factors on microclimatic conditions in Dinaric fir-beech forests
Janez Kermavnar, Mitja Ferlan, Aleksander Marinšek, Klemen Eler, Andrej Kobler, Lado Kutnar, 2020, izvirni znanstveni članek

Povzetek: Forest microclimate is strongly affected by local topography and management activities, as these directly alter overstory structure. In the present work we analysed the dependence of observed patterns of spatio-temporal microclimatic variations on topographic, canopy- and management-related factors. A forestry experiment was conducted in managed fir-beech forests in the Dinaric Mountains (Slovenia), which are characterized by rugged karstic terrain with numerous sinkholes. In 2012, cutting treatments representing a range in the intensity of overstory removal were performed: uncut controls (CON), 50% cut of stand growing stock (intermediate management intensity % IMI) and 100% cut (high management intensity % HMI) creating 0.4 ha canopy gaps. Fine-scale variation in aspect and slope and its effects on microclimate was assessed by comparing central, south-facing and north-facing within-sinkhole positions. We measured microclimatic variables (air temperature % T, relative humidity % RH) 0.5 m above the ground over three consecutive post-treatment growing seasons. Microclimatic variables showed an increase (T and vapour pressure deficit % VPD) or decrease (RH) with management intensity. Daily Tmax and VPDmax in HMI treatment were up to 5.9°C (on average 3.5°C) and up to 1.4 kPa (on average 0.6 kPa) higher than those in CON treatment, respectively, whereas daily RHmin was up to 22.7 (on average 13.0) percentage points lower. Regarding intra-seasonal patterns, microclimatic differences between treatments were largest during the summer. South-facing plots in the HMI treatment overall exhibited the most extreme conditions, i.e. the highest Tmax and lowest RHmin. Differences in microclimate between treatments were strongly modulated by canopy cover. The results also suggest that overstory removal increases topography-mediated variation in microclimate, as evidenced by significant differences in T, RH and VPD along the fine-scale topographic gradient within the created canopy gaps.
Ključne besede: tree cutting, air temperature, relative humidity, vapour pressure deficit, karst topography, canopy cover
Objavljeno v DiRROS: 08.10.2020; Ogledov: 1349; Prenosov: 570
.pdf Celotno besedilo (1,59 MB)
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Patterns of understory community assembly and plant trait-environment relationships in temperate SE European forests
Janez Kermavnar, Lado Kutnar, 2020, izvirni znanstveni članek

Povzetek: We analyzed variation in the functional composition and diversity of understory plant communities across different forest vegetation types in Slovenia. The study area comprises 10 representative forest sites covering broad gradients of environmental conditions (altitude, geology, light availability, soil type and reaction, nutrient availability, soil moisture), stand structural features and community attributes. The mean and variation of the trait values were quantified by community-weighted means and functional dispersion for four key plant functional traits: plant height, seed mass, specific leaf area and leaf dry matter content. At each study site, forest vegetation was surveyed at two different spatial scales (4 and 100 m2 ) in order to infer scale-dependent assembly rules. Patterns of community assembly were tested with a null model approach. We found that both trait means and diversity values responded to conspicuous gradients in environmental conditions and species composition across the studied forests. Our results mainly support the idea of abiotic filtering: more stressful environmental conditions (e.g., high altitude, low soil pH and low nutrient content) were occupied by communities of low functional diversity (trait convergence), which suggests a selective effect for species with traits adapted to such harsh conditions. However, trait convergence was also detected in some more resource-rich forest sites (e.g., low altitude, high soil productivity), most likely due to the presence of competitive understory species with high abundance domination. This could, at least to some extent, indicate the filtering effect of competitive interactions. Overall, we observed weak and inconsistent patterns regarding the impact of spatial scale, suggesting that similar assembly mechanisms are operating at both investigated spatial scales. Our findings contribute to the baseline understanding of the role of both abiotic and biotic constraints in forest community assembly, as evidenced by the non-random patterns in the functional structure of distinct temperate forest understories.
Ključne besede: functional composition, functional diversity, ecological gradients, abiotic filtering, trait convergence, trait divergence, spatial scale, forest ground-layer vegetation, Slovenia
Objavljeno v DiRROS: 26.05.2020; Ogledov: 1926; Prenosov: 1279
.pdf Celotno besedilo (4,12 MB)
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67.
Utrinki v spomin pedologu in fitocenologu Miheju Urbančiču (15. 1. 1949- 27. 6. 2019)
Lado Kutnar, Primož Simončič, Igor Dakskobler, 2020, poljudni članek

Ključne besede: biografija
Objavljeno v DiRROS: 02.05.2020; Ogledov: 2035; Prenosov: 457
.pdf Celotno besedilo (135,49 KB)

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Delavnice s področja fitocenologije in pedologije za pripravo strokovnih izhodišč za izdelavo gozdnogospodarskih načrtov območij
Valerija Babij, Lado Kutnar, Aleksander Marinšek, Janez Kermavnar, 2020, strokovni članek

Povzetek: V letu 2019 smo v okviru Javne gozdarske službe v skupni organizaciji Zavoda za gozdove Slovenije in Gozdarskega inštituta Slovenije za gozdarje načrtovalce organizirali niz fitocenološko-pedoloških delavnic. Izvedli smo eno celodnevno teoretično delavnico v obliki predavanj in štiri terenske: za panonsko, primorsko, dinarsko in alpsko geografsko območje. Namen delavnic je priprava podlag strokovnih izhodišč na področju gozdnih rastišč, združb in gozdnih tal za izdelavo območnih gozdnogospodarskih načrtov za obdobje 2021%2030.
Ključne besede: fitocenologija, gozdna vegetacija, gozdna rastišča, gozdne združbe, rastiščni tip, gozdna tla, gozdnogospodarsko načrtovanje, prenos znanja, Slovenija
Objavljeno v DiRROS: 06.04.2020; Ogledov: 2288; Prenosov: 745
.pdf Celotno besedilo (446,12 KB)

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Comparing observer performance in vegetation records by efficiency graphs derived from rarefaction curves
Walter Seidling, Leena Hamberg, František Máliš, Maija Salemaa, Lado Kutnar, Janusz Czerepko, Thomas Kompa, Václav Buriánek, Jean-Luc Dupouey, Anna Vodálová, Roberto Canullo, 2020, izvirni znanstveni članek

Povzetek: Species richness is a key variable in measuring diversity of ecological communities. It is crucial to get reliable estimates for the number of plant species in space (mapping) and % even more important in the context of monitoring % over time. Therefore, knowledge on error rates related to recordings of species numbers should be considered in such inventories. The performance of observers in four field tests to capture species numbers carried out in forest ecosystems in central and southern Europe were compared. Observer-related species accumulation (rarefaction) curves and derived efficiency curves were analysed, resulting in mean error rates of 29.7% and 39.4% over series of plots sized 4m2 and 100m2 respectively. As a new approach individual rarefaction and efficiency curves reveal site-specific and spatially differentiated capabilities of observers to register plant species. Since expertise and individual searching strategies are difficult to parametrise, reasons for variation in error rates remain largely unknown. However, statistical modelling with site- and scale-specific mean error rates gave an overview on important influential factors like location, scale, spatial integration, and their interactions. Our results underline the importance to incorporate specific training and inter-comparison measures in monitoring programs and critical perception of results on temporal changes of species richness.
Ključne besede: species richness, observer error, overlooking rate, misidentification rate, singleton species, ICP Forests
Objavljeno v DiRROS: 20.02.2020; Ogledov: 1650; Prenosov: 637
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