The diversity of saproxylic beetles’ community from the Natural Reserve Voievodeasa Forest, North-Eastern Romania

Nature reserves harbour considerable richness and diversity of saproxylic organisms since dead wood is preserved in situ, this being also the case of Voivodeasa beech-spruce-fir forest in North-Eastern Romania, the area investigated under the present research. Flight interception traps were employed to capture insects during a vegetation season with the goal to characterize saproxylic Coleoptera community in terms of diversity and several other structural features. Among the captured insects, the majority pertained to obligate saproxylic species (217 species). However, the unexpected high species richness corresponded to an area with modest representation of deadwood due to previous status of commercial forest. The identified beetles were members of different habitat-guilds depending on what type of substrate they colonized: recently dead wood (23%), decomposed dead wood (41%), wood inhabiting fungi (34%) and treehollow detritus (2%). According to their trophic position, the identified saproxylic beetles pertained to the following guilds: xylophagous (40%), mycetophagous (39%), predatory (14%), and species relying on other food resources. The observed richness corresponded to the case of hyperdiverse communities where sampling never leads to the stabilization of species richness under a realistic sampling scheme. The diversity profiles constructed on Shannon, Gini-Simpson, Berger-Parker and evenness indices for the pooled inventory and for separate samples across the vegetation season indicated the aggregated saproxylic community as highly diverse and highly uneven, with rich representation of rare species, dominated by few abundant species. We assembled four bipartite, unweighted, and undirected networks to approach the temporal changes across the sampling period extended over one vegetation season. The topology of beetles’ community and of the three main trophic guilds (xylophagous, mycetophagous and predatory) networks linked to time sequences are characterized by high connectance, high nestedness and modularity, with the exception of the mycetophagous sub-network not displaying significant modularity. Among the identified species, 13% indicate high degree of naturalness of the Voievodeasa forest. 62 of the identified species are included in the Red List of European Saproxylic Beetles of which five are near threatened (Protaetia fieberi, Cucujus cinnaberinus, Crepidophorus mutilatus, Ceruchus chrysomelinus, Prostomis mandibularis), Ischnodes sanguinolentus is vulnerable and Rhysodes sulcatus is an endangered species. During the study, two Coleoptera species, new for Romanian insect fauna were identified: Denticollis interpositus Roubal, 1941 and Hylis procerulus (Mannerheim 1823).

Usage of Fermental Traps for the Study of the Species Diversity of Coleoptera

The possibilities of applying various methods to study Coleoptera give unexpected and original results. The studies were carried out with the help of fermental crown traps in 2018–2020 on the territory of eight regions in the central part of European Russia. The biodiversity of the Coleoptera that fall into crown traps includes 294 species from 45 families. The number of species attracted to the fermenting bait is about a third of the total number of species in the traps (this is 97.4% of the number of all of the caught specimens). The largest number of species that have been found in the traps belong to the families Cerambycidae, Elateridae and Curculionidae. The most actively attracted species mainly belong to the families Cerambycidae, Nitidulidae and Scarabaeidae. The species of these families are equally attracted by baits made of beer, white and red wines. In order to identify the Coleoptera biodiversity of a particular biotope, two-year studies are sufficient, and they should be carried out throughout the vegetation season. Especially good results can be obtained from studies of rare species that are actively attracted by such baits. It is possible to study the vertical–horizontal distribution of Coleoptera fauna in individual biotopes.

Effect of wastewater sludge treatment on early growth and physiological responses of willow (Salix spp.) and poplar (Populus spp.) pot-grown plants

Combining biomass production from fast-growing woody species with wastewater treatment is an attractive concept from the economic, energy and environmental points of view. A pilot experiment on study-ing the effect of wastewater treatment on the early growth and initial physiological responses of willow and poplar plants was carried out in greenhouse conditions. The survival, height growth, net photosyn-thesis, stomatal conductance and transpiration of two hybrid clones of black poplar (Populus x euroameri-cana (Dode) Guinier) (I-214 and I-45/51) and white willow (S. alba L.) pot-grown plants treated with different doses of agrochemically characterised wastewater sludge were studied during the establishment year. The height growth and number of resprouted willow shoots were also measured during the second year after cutting, at the end of the vegetation season. While the early growth height of poplar clones was markedly affected by the clone origin and wastewater sludge treatment, the latter did not considerably influence the height of the willow plants either during the establishment and the following year, but essentially increased the number of resprouted shoots during the second vegetation season. The rate of CO2 assimilation of willow plants was significantly influenced by the wastewater sludge treatment, with plants grown at the higher doses displaying higher photosynthetic performance. The application of wastewater sludge had no essential impact on the values of the physiological parameters of the poplar plants, but particular responses were found among the clones.

Usage of Fermental Traps for Studying the Species Diversity of Coleoptera

The possibilities of applying various methods to study Coleoptera give unexpected and original results. The studies were carried out with the help of fermental crown traps in 2018-2020 on the territory of eight regions in the central part of European Russia. The biodiversity of Coleoptera that fall into crown traps includes 294 species from 45 families. The number of species attracted to the fermenting bait is about a third of the total number of species in the traps (this is 97.4% of the number of all caught specimens). The largest number of species that have been found in traps belong to the families Cerambycidae, Elateridae and Curculionidae. The most actively attracted species mainly belong to the families Cerambycidae, Nitidulidae and Scarabaeidae. Species of these families are equally attracted by baits made of beer, white and red wines. To identify the Coleoptera biodiversity of a particular biotope, two-year studies are sufficient, which should be carried out throughout the vegetation season. Especially good results can be obtained from studies of rare species that are actively attracted by such baits. It is possible to study the verti-cal-horizontal distribution of Coleoptera fauna in individual biotopes.

European beech is a net annual source of methane (CH4)

<p>Trees are known to be sources of methane (CH<sub>4</sub>), an important greenhouse gas, into the atmosphere. However, still little is known about the seasonality of the tree stem CH<sub>4</sub> fluxes, particularly for the dormant season, and about the impact of environmental parameters on this gas exchange. This makes the estimation of net annual ecosystem CH<sub>4</sub> fluxes difficult.</p><p>We determined seasonal dynamics of CH<sub>4</sub> exchange of mature European beech stems (<em>Fagus sylvatica</em>) and of adjacent forest floor in a temperate montane forest of White Carpathians, Czech Republic, from November 2017 to December 2018. We used static chamber methods and gas chromatographic analyses. We aimed to understand the unknown role in seasonal changes of CH<sub>4</sub> fluxes of these forests, and the spatiotemporal variability of the tree fluxes.</p><p>The beech stems were net annual sources for atmospheric CH<sub>4</sub>, whereas the forest floor was a predominant sink for CH<sub>4</sub>. The stem CH<sub>4</sub> emissions showed high inter-individual variability and clear seasonality following the stem CO<sub>2</sub> efflux. The fluxes of CH<sub>4</sub> peaked during the vegetation season, and remained low but significant to the annual totals during winter dormancy. By contrast, the forest floor CH<sub>4</sub> uptake followed an opposite flux trend with low CH<sub>4</sub> uptake detected in the winter dormant season and elevated CH<sub>4</sub> uptake during the vegetation season. Based on our preliminary analyses, the detected high spatial variability in stem CH<sub>4</sub> emissions can be explained neither by the CH<sub>4</sub> exchange at the forest floor level, nor by soil CH<sub>4</sub> concentrations, soil water content and soil temperature, all measured in vertical soil profiles close to the studied trees.</p><p>European beech trees, native and widely spread species of Central Europe, seem to markedly contribute to the seasonal dynamics of the ecosystem CH<sub>4</sub> exchange, and their CH<sub>4</sub> fluxes should be included into forest greenhouse gas emission inventories.</p><p> </p><p><em>Acknowledgement</em></p><p><em>This research was supported by the Czech Science Foundation (17-18112Y), National Programme for Sustainability I (LO1415), CzeCOS (LM2015061), and SustES - Adaptation strategies for sustainable ecosystem services and food security under adverse environmental conditions (CZ.02.1.01/0.0/0.0/16_019/0000797). We thank Libor Borák and Leszek Dariusz Laptaszyński for their technical and field support.</em></p><p> </p>

Agaricoid basidiomycetes of the natural park Uch-Enmek of Altai Republic

The data on locations, habitats and vegetation season of 205 species agaricoid basidiomycetes new for the Karakol natural park UchEnmek (Altai Republic) are presented. They were collected in the steppe, forest, forest-steppe and highland belts. Among them 32 species are recorded for the first time for Altai Republic, 6 species are rare in Altai Republic and Western Siberia.

Multi-Temporal Analysis and Trends of the Drought Based on MODIS Data in Agricultural Areas, Romania

The aim of this study is to analyze the performance of the Drought Severity Index (DSI) in Romania and its validation based on other data sources (meteorological data, soil moisture content (SMC), agricultural production). Also, it is to assess the drought based on a multi-temporal analysis and trends of the DSI obtained from Terra MODIS satellite images. DSI is a standardized product based on evapotranspiration (ET) and the Normalized Difference Vegetation Index (NDVI), highlighting the differences over a certain period of time compared to the average. The study areas are located in Romania: three important agricultural lands (Oltenia Plain, Baragan Plain and Banat Plain), which have different environmental characteristics. MODIS products have been used over a period of 19 years (2001–2019) during the vegetation season of the agricultural crops (April–September). The results point out that those agricultural areas from the Baragan Plain and Oltenia Plain were more affected by drought than those from Banat Plain, especially in the years 2002, 2007 and 2012. Also, the drought intensity and the agricultural surfaces affected by drought decreased in the first part of the vegetation season (March–May) and increased in the last part (August–September) in all three study areas analyzed. All these results are confirmed by those of the Standardized Precipitation Evapotranspiration Index (SPEI) and Soil Moisture Anomaly (SMA) indices.

Seasonal Changes in the Content of Photosynthetic Pigments of Dominant Macrophytes in the Bardača Fishpond Area

In this paper, changes in the content of photosynthetic pigments during the vegetation season in the leaves of Phragmites communis Trin., Salvinia natans (L.) All., Trapa natans L. and Utricularia vulgaris L. in the area of Bardača fishpond (Sinjak pond) were monitored. Physical and chemical characteristics of water are defined in order to determine their association with the content of photosynthetic pigments. The obtained results indicate the specificity in the content of photosynthetic pigments between aquatic macrophytes and significant variations during the vegetation season. The maximum content of pigments was determined in the leaves of the emerged species, while the minimum content was measured in the submerged and floating leaves. The investigated macrophytic species showed a similar trend in the total chlorophyll content during the vegetation period; with two maximums recorded – May and September, while the minimum values were recorded with the senescence process (October). Total chlorophyll and carotenoids were in a negative correlation with temperature, pH, saturation, water transparency and orthophosphate content in water. On the other hand, they were in a positive correlation with the content of nitrates in water. The correlation analysis of the physical and chemical parameters of water quality and the concentration of macrophytes photosynthetic pigments showed a significant influence of certain abiotic factors on the photosynthetic pigments’ content in the leaves of Phragmites communis Trin., Salvinia natans (L.) All., Trapa natans L. and Utricularia vulgaris L.

The Change of pH Value and Octolasion cyaneum Savigny Earthworms’ Activity under Stubble Crops after Spring Triticale Continuous Cultivation

The changes of pH value followed by various agricultural practices are crucial for biotic components of soil, along with other environmental factors, like temperature and moisture content. In this paper, the earthworms population in triticale continuous cultivation was monitored. Their presence associated with various agrotechnical methods (e.g., stubble crops maintained as mulch, mineral fertilization without pesticides) were assessed twice by the handsorting method, and their presence during the triticale vegetation season (occurrence of coprolites) were monitored too. The aim of the study was to analyse the distribution of earthworm populations in cereal continuous cultivation fields, and whether they prefer any of the stubble crop species (Sinapis alba L., Phacelia tanacetifolia Benth., Fagopyrum esculentum Moench.), which were sown after triticale harvest. The results reveal the most abundant earthworms occurence in the F. esculentum objects (43.1% of all sampled earthworms, which consists of 42% and 47.2% of all sampled matured and juveniles individuals, respectively), and species homogeneity (dominate Octolasion cyaneum Savigny, 1826). The changes of pH varied through the triticale vegetation season, but didn’t exhibit severe variation between sampling sites. Using earthworm services in cropping systems after having enticed them to the field through stubble crop has the potential to boost agricultural sustainability. Their ecological preferences, along with their trophic behaviour, have already been put in place to complete a case study of the autecology of the O. cyaneum Savigny 1826 species.