11. Empirical vs. light-use efficiency modelling for estimating carbon fluxes in a mid-succession ecosystem developed on abandoned karst grasslandKoffi Dodji Noumonvi, Mitja Ferlan, 2020, original scientific article Abstract: Karst systems represent an important carbon sink worldwide. However, several phenomena such as the CO2 degassing and the exchange of cave air return a considerable amount of CO2 to the atmosphere. It is therefore of paramount importance to understand the contribution of the ecosystem to the carbon budget of karst areas. In this study conducted in a mid-succession ecosystem developed on abandoned karst grassland, two types of model were assessed, estimating the gross primary production (GPP) or the net ecosystem exchange (NEE) based on seven years of eddy covariance data (2013%2019): (1) a quadratic vegetation index-based empirical model with five alternative vegetation indices as proxies of GPP and NEE, and (2) the vegetation photosynthesis model (VPM) which is a light use efficiency model to estimate only GPP. The Enhanced Vegetation Index (EVI) was the best proxy for NEE whereas SAVI performed very similarly to EVI in the case of GPP in the empirical model setting. The empirical model performed better than the VPM model which tended to underestimate GPP. Therefore, for this ecosystem, we suggest the use of the empirical model provided that the quadratic relationship observed persists. However, the VPM model would be a good alternative under a changing climate, as it is rooted in the understanding of the photosynthesis process, if the scalars it involves could be improved to better estimate GPP. Keywords: eddy covariance, carbon flux, GPP, NEE, vegetation indices, remote sensing, satellite data, GPP map Published in DiRROS: 03.01.2022; Views: 691; Downloads: 464 Full text (3,07 MB) This document has many files! More... |
12. Short-term impacts of harvesting intensity on the upper soil layers in high karst Dinaric fir-beech forestsEmira Hukić, Matjaž Čater, Aleksander Marinšek, Mitja Ferlan, Milan Kobal, Daniel Žlindra, Hamid Čustović, Primož Simončič, 2021, original scientific article Abstract: The present study addresses the short-term effects of different harvest intensities under close-to-nature selective management on the upper soil layers in Slovenian and Bosnian Dinaric karst fir-beech forests. The different harvest intensities coincided with the single-tree and irregular shelterwood management, common in the region. The effect of harvesting intensity on the upper soil layers (Ol, Of, Ol and 0%10 cm mineral soil) was investigated by a repeated measurements experiment in Slovenia on 27 research plots in close-to nature managed forests. The properties of the upper layers (concentration of SOC and TN, C/N ratio, weights, BD and SOC stocks) were analyzed twice, before (2011) and after (2014) treatment of 50% and 100% harvest intensity in relation to the total standing growing stock of trees. As a control, we used no-treatment <20% harvesting intensity plots. To extend this experiment, we added three comparable plots from the Bosnian site: one in an old-growth forest with 0% harvest intensity and two in the managed forest with <20% harvest intensity. The results of the assessment of mean differences indicated a significant influence of harvesting intensity on the decrease in SOC, TN concentrations, weights and SOC stocks in the organic layers and the increase in BD and SOC stocks in the 0%10 cm mineral soil. The highest relative decreases in Ol, Of and Oh SOC stocks occurred in 50% (%10 and %38%) and 100% (%16 and %49%) harvest intensities. Negligible relative differences in both organic and 0%10 cm mineral layers were found for the <20% harvest intensity in the region. The change in forest light conditions resulting from differences in canopy openness as a function of applied harvest intensity explained the significant difference in the properties of the upper soil layers. The impact of the short-term losses in SOC stocks, in terms of overall soil productivity, may depend on the regeneration dynamics and melioration methods. Keywords: close-to-nature forest management, harvest intensity, Calcic Cambisol, forest soil, soil organic carbon Published in DiRROS: 10.05.2021; Views: 1086; Downloads: 777 Full text (18,42 MB) This document has many files! More... |
13. The effect of harvesting on national forest carbon sinks up to 2050 simulated by the CBM-CFS3 model : a case study from SloveniaJernej Jevšenak, Matija Klopčič, Boštjan Mali, 2020, original scientific article Keywords: carbon, forest reference levels, forest management, harvesting scenarios, yield curves, UNFCCC, prirastne krivulje, UNFCCC Published in DiRROS: 19.10.2020; Views: 1277; Downloads: 898 Full text (3,39 MB) This document has many files! More... |
14. Harvesting intensity and tree species affect soil respiration in uneven-aged Dinaric forest standsMatjaž Čater, Eva Dařenová, Primož Simončič, 2021, original scientific article Abstract: Forest management, especially thinning and harvesting measures, has a significant impact on the forest carbon balance especially in the forests with long-term continuous cover history. We measured soil CO2 efflux (Rs) in three forest complexes of mixed, uneven-aged Dinaric forests with predominating silver fir (Abies alba Mill.), beech (Fagus sylvatica L.), and Norway spruce (Picea abies Karst.). Rs was measured after removal of mature forest stands with 50% and 100% intensity of living stock and compared with Rs on the control plots without any applied silvicultural measures. Rs was measured monthly in three consecutive 2012, 2013 and 2014 growing periods. Soil CO2 efflux increased after harvest of both intensities in all studied forest stands. The biggest increase was measured in beech stands and amounted up to 47 and 69% for 50% and 100% harvest intensities, respectively. The effect of harvest on Rs in spruce and fir stands was similar - up to 26% for 50% harvest intensity and 48% for 100% harvest intensity. Despite the biggest increase after harvest, Rs in beech stands returned the fastest to the level of the uncut forest and this levelling period (LP) took 14-17 months with a little delay of the stands with 100% harvest intensity. The LP for all fir stands, for spruce stands with 50% harvest intensity and for one spruce stand with 100% harvest intensity, was 26-29 months. At two spruce stands with 100% harvest intensity we did not record Rs levelling during our three-year study. This study involved forest stands of three predominating tree species growing under the same conditions, which allowed us to determine the species-specific sensitivity of soil CO2 efflux to the different harvesting intensities. Keywords: harvesting intensity, soil CO2 efflux, silviculture, carbon release, silver fir forests, Beech forestrs, Norway spruce forests Published in DiRROS: 08.10.2020; Views: 1321; Downloads: 564 Full text (1,11 MB) This document has many files! More... |
15. Catalytic cracking of biomass-derived hydrocarbon tars or model compounds to form biobased benzene, toluene, and xylene isomer mixturesAndrii Kostyniuk, Miha Grilc, Blaž Likozar, 2019, review article Keywords: biomass-derived tar compounds, catalytic cracking process, benzene/toluene/xylene, BTX, metal-promoted zeolite materials, activated carbon supports Published in DiRROS: 23.01.2020; Views: 1974; Downloads: 1379 Full text (2,52 MB) This document has many files! More... |
16. Estimation of carbon fluxes from Eddy covariance data and satellite-derived vegetation indices in a Karst grassland (Podgorski Kras, Slovenia)Koffi Dodji Noumonvi, Mitja Ferlan, Klemen Eler, Giorgio Alberti, Alessandro Peressotti, Sofia Cerasoli, 2019, original scientific article Keywords: eddy covariance, carbon flux, GPP, NEE, vegetation indices, remote sensing, satellite data, GPP map Published in DiRROS: 10.04.2019; Views: 2537; Downloads: 1532 Full text (11,09 MB) This document has many files! More... |
17. A review of plasma-assisted catalytic conversion of gaseous carbon dioxide and methane into value-added platform chemicals and fuelsHarinarayanan Puliyalil, Damjan Lašič Jurković, Venkata D. B. C. Dasireddy, Blaž Likozar, 2018, review article Keywords: atmospheric pressure plasma, carbon capture and utilisation, CCU, chemical reaction engineering, heterogeneous catalysis design, natural gas valorisation, plasma catalysis Published in DiRROS: 22.08.2018; Views: 2970; Downloads: 1631 Full text (1,30 MB) This document has many files! More... |
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