Ocena sprememb organske snovi v tleh na ploskvi Brdo glede na različne scenarije podnebnih sprememb z uporabo modela Yasso07

The forest soil can act as an important sink for CO2 and in that respect also appears in the national Kyoto reports, where a distinction is made between carbon accumulated in litter and organic soil horizons and carbon accumulated in mineral soil layers. There is a multitude of dynamic models of organic carbon (Corg) change in the soil particularly due to different environmental and anthropogenic factors. The purpose of this paper is the Yasso07 model application on the “Brdo” plot, which is part of the ICP Forest Level II plots of Slovenia. The Yasso07 model describes the decomposition of organic matter in the forest soil by dividing litter inputs into different components with varying decomposition rates. Here, the temporal change of soil Corg in various scenarios of future climate change (increase in air temperature, change in precipitation) was predicted. The difference between the measured amount and the model-predicted amount of Corg in the soil for the current climate on the Brdo plot is 6.4 t C ha-1 (88.6 t C ha-1 measured vs. 95.0 t C ha-1 predicted). Taking into consideration the climate change scenarios for Slovenia, Corg stock is expected to decrease in the future according to Yasso07 projections in all scenarios of climate change. The estimate of 100-year decrease of Corg is the largest for scenario, when large increase of both temperature and precipitation is expected (18.2%) and smallest when small temperature increase and precipitation decrease are predicted (9.3%). Assuming stable litter input, larger influence on Corg decrease was predicted for the temperature change compared to precipitation change. However, many uncertainties are included in model estimates ranging from litter input estimates, climate change uncertainties, climate-litter production feedbacks, starting value estimates, etc. The determination of the uncertainty of model calculations is a requirement for conducting simulations and their interpretation

Uporaba programskega okolja R v prostorskih analizah

R is a powerful and increasingly popular programming language with strong graphical and presentation features and large expanŽdability. Although primarily intended for statistical computing, R has paved its way to the field of GIS through the development of specialized extension packages. It offers a wide range of functions at all GIS levels: data acquisition, data manipulation, graphical reŽpresentation and quantitative analysis. The paper presents R as an open source alternative to the existing commercial GIS software. It proves especially well when advanced quantitative methods on spatial data are needed (e.g. spatial modelling). We demonstrate R capabilities through spatial analysis of forest area in Snežnik (South Slovenia), where the possibilities of data import, conversion and export into various GIS formats and possibilities of geostatistics, spatial modelling and spatial visualization are demonstrated.R je zmogljiv in vse bolj priljubljen programski jezik s poudarjenimi grafičnimi in predstavitvenimi funkcijami ter veliko možnostjo razširitve. Čeprav primarno namenjen statističnemu računanju, si je R z razvojem specialnih razširitvenih knjižnic utrl pot tudi na področje GIS. Omogoča široknabor funkcij na vseh ravneh GIS: na nivoju zajemanja podatkov, na nivoju manipulacije podatkov ter na nivoju grafičnih predstavitev in kvantitativnih analiz. V prispevku predstavljamo R kot odprtokodno alternativoobstoječim komercialnim GIS- orodjem, ki se izkaže še posebno tedaj, kadar želimo na prostorskih podatkih upoŽrabiti zahtevnejše kvantitativne metode (npr. prostorska modeliranja). Prikazujemo ga na primeru prostorskih analiz gozdŽnega območja na Snežniku (južna Slovenija), kjer demonstriramo možnosti vnosa podatkov, transformiranja in shranjevanja različnih GIS-podlag, možnosti geostatistike, prostorskega modeliranja in prostorske vizualizacije

Seed Viability and Potential Germination Rate of Nine Endemic Boswellia Taxa (Burseraceae) from Socotra Island (Yemen)

The endemic Boswellia species (Burseraceae) on Socotra Island (Yemen) are of great local significance due to their various local ethnobotanical uses. However, despite the fact that these trees are endangered, little is known about their biology. We tested seed germination rates in controlled experiments (trials of 21 days) for two subsequent years and for nine endemic taxa of Boswellia occurring on Socotra Island. For this, seeds were collected island-wide from a wide range of localities and for several populations per species. We observed differences in germination among Boswellia species, among species and localities and among both years, which indicates that the development of seeds is strongly affected by external ecological factors. Although we noted a large variation in seed germination (relatively high in Boswellia socotrana), and half of the species showed relatively low mean daily germination, our study indicated that all endangered endemic Frankincense Tree taxa of Socotra harbor the potential for in situ conservation through recruitment, given that known impacts can be reduced in local replantation areas (e.g., grazing).O

Indicators of sustainable forest management: application and assessment

Report of the international project Life ManForCBD

Vegetation dynamics in the submediterranean region of Slovenia

doktorska disertacij

Urban heat islands in relation to green land use in European cities

The phenomenon of increased temperature in cities compared to their rural environs, also referred to as urban heat island, is one of the most evident anthropogenic climatic modifications. Introducing green spaces and vegetation is the fastest, simplest, and a highly effective way of mitigating and adapting urban temperature conditions. The primary goal of the presented research is to identify the interrelationship between urban heat island magnitude (UHIM) and urban green infrastructure extent, shape, and distribution on European scale comparing different green space planning traditions % planning families (PFs). The UHIM for the European cities was calculated based on a reconstructed MODIS LST dataset of a period of ten years. The reasons for the arrangement of UHIMs according to PFs and green land use are not easily explained and are certainly influenced by a number of various conditions in different PFs. UHIM increases with the longitude of cities. In some of the PFs, the relation between the UHIM and land use proportion is characteristic for certain land uses, but a considerable difference between PFs regarding land use proportion with significant impact on UHIM can only be noted in case of a forest. The configuration and composition of the forest correlate with UHIM with statistical significance, but the share of the forest does not affect UHI in all PFs in the same way. While a higher proportion of forest, higher largest patch index, higher mean patch area, higher edge density and higher proportional landscape core is associated with a lower UHIM in the New member and Mediterranean PFs, the relationship in other PFs is reversed. Information on general patterns of UHIM occurrence in relation to urban green infrastructure characteristics could help urban planners and politicians introduce changes on the local level, which would help providing nature-based solutions for the mitigation of the UHI phenomenon

Assessment of organic matter changes in the soil of the Brdo plot under different climate change scenarios through the Yasso07 model application

The forest soil can act as an important sink for CO2 and in that respect also appears in the national Kyoto reports, where a distinction is made between carbon accumulated in litter and organic soil horizons and carbon accumulated in mineral soil layers. There is a multitude of dynamic models of organic carbon (Corg) change in the soil particularly due to different environmental and anthropogenic factors. The purpose of this paper is the Yasso07 model application on the “Brdo” plot, which is part of the ICP Forest Level II plots of Slovenia. The Yasso07 model describes the decomposition of organic matter in the forest soil by dividing litter inputs into different components with varying decomposition rates. Here, the temporal change of soil Corg in various scenarios of future climate change (increase in air temperature, change in precipitation) was predicted. The difference between the measured amount and the model-predicted amount of Corg in the soil for the current climate on the Brdo plot is 6.4 t C ha-1 (88.6 t C ha-1 measured vs. 95.0 t C ha-1 predicted). Taking into consideration the climate change scenarios for Slovenia, Corg stock is expected to decrease in the future according to Yasso07 projections in all scenarios of climate change. The estimate of 100-year decrease of Corg is the largest for scenario, when large increase of both temperature and precipitation is expected (18.2%) and smallest when small temperature increase and precipitation decrease are predicted (9.3%). Assuming stable litter input, larger influence on Corg decrease was predicted for the temperature change compared to precipitation change. However, many uncertainties are included in model estimates ranging from litter input estimates, climate change uncertainties, climate-litter production feedbacks, starting value estimates, etc. The determination of the uncertainty of model calculations is a requirement for conducting simulations and their interpretation

Post-harvest forest herb layer demography : general patterns are driven by pre-disturbance conditions

Timber harvesting constitutes extensive anthropogenic disturbance in temperate forests, producing a broad range of ecological impacts that most often enhance the demographic processes of vegetation. This study monitored post-harvest herb layer demography over a 6-year period in mesic Dinaric fir-beech forests (Slovenia), a vascular plant diversity hotspot among European forests. Three experimental harvesting intensities, i.e. full harvest (FH), partial harvest (PH) and a control treatment (NH), were each applied over a circular area of 4000 m2 and replicated three times at each of three study sites. Vegetation sampling was conducted before harvesting (in 2012), and two (2014) and six (2018) years following it, in a 400 m2 circular plot positioned in the centre of each treatment area. We focused on identifying general demographic patterns and evaluating the effects of various pre-disturbance abiotic and biotic predictors on compositional responses to disturbance. Two years after harvest (2012-2014), compositional shifts were larger than those in the next 4-year period (2014-2018), confirming the general theoretical prediction that species turnover rate decreases along a successional gradient. The degree of compositional shifts in gaps (FH) and thinned stands (PH) was affected by local abiotic factors (geomorphology of karst sinkholes) and community attributes, such as pre-harvest species richness. Our results indicate that compositional stability is positively associated with pre-disturbance species richness. Over the whole study period, increases in plot-level species richness (alpha diversity) and overall enrichment of the species pool (gamma diversity) were accompanied by compositional convergence, i.e. a decline in floristic dissimilarity (beta diversity) between and within study sites. However, the observed tendency towards homogenization was rather weak and would have been even more pronounced if the demographic type of persistent resident species had not shown a high degree of resistance, thus leaving a strong imprint on post-harvest vegetation development by preserving the forest characteristics of the herb layer community