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Abstract

Mantle vegetation includes plant communities dominated mostly by shrubs and occurs in habitats where the typical tree layers meet difficulties to evolve. This study was conducted in three areas of Bulgaria – Western Balkan Range, Western Sredna Gora Mt. and the Fore-Balkan. Numerical classification and ordination were performed by PC-ORD and JUICE software packages. Diagnostic species were determined by calculating the Phi-coefficient. Two associations and one plant community of the Berberidion alliance were recognized – Corno-Ligustretum Horvat ex Trinajstić ---amp--- Z. Pavletić 1991, Pruno spinosae-Ligustretum vulgaris Tüxen 1952 and Elytrigia repens-Crataegus monogyna community. The latter considered as a successional stage of shrub encroachment into the grasslands. Its species composition is very close to that of the ass. Corno-Ligustretum. The species composition of ass. Pruno-Ligustretum represents a mixture of species characteristic for dry and mesic grasslands, fringe and forest vegetation. The Crataego-Prunetea class is still poorly studied in Bulgaria and much more data from all regions in the country have to be collected.

Abstract

Echinophora spinosa L., a perennial member of the Apiaceae (Umbelliferae) family is known to be native to southern Europe and Algeria. More recently this taxon was collected from Tabarka (Jendouba-Kroumiria, North-Western of Tunisia) and is reported as a new species for the terrestrial flora of Tunisia. It is described and illustrated and notes on its ecology and phytosociological remarks are provided.

Abstract

Based on hierarchical classification of more than 300 phytosociological relevés of basophilic black and (or) Scots pine communities in the Southern, Eastern and Southeastern Alps we described a new association Rhodothamno chamaecisti-Pinetum sylvestris, into which we classify stands that have until now been discussed in the framework of subassociations Fraxino orni-Pinetum nigrae pinetosum sylvestris, laricetosum deciduae and (partly) caricetosum humilis, and are floristically slightly similar also to certain forms of the association Erico-Pinetum sylvestris. The stands of the new association are for now classified into Natura 2000 habitat type Southeastern-European Pinus sylvestris forests (91R0), within it we propose a special habitat subtype Southeastern-Alpine Scots pine forests, and into a new forest site type Southeastern-Alpine Scots pine forest. At the contact of the Julian and Dinaric Alps we described a new subassociation Genisto januensis-Pinetum sylvestris campanuletosum cespitosae, which comprises also a Natura 2000 species Primula carniolica.

Abstract

The study presents a floristic-sociological classification of the forest vegetation of Kyiv urban area. We identified 18 syntaxa within 7 classes, 7 orders, 8 alliances, and 3 new associations were allocated (Aristolochio clematitis-Populetum nigrae, Galio aparines-Aceretum negundi, Dryopterido carthusianae-Pinetum sylvestris). We analyzed vegetation data using quantitative approaches of ordination and phytoindication. Considering many relevés of transitional nature in the collected data on urban forests, the clustering algorithm of DRSA (Distance-Ranked Sorting Algorithm) was applied to classify vegetation matrix. Large-scale comparative floristic analysis of syntaxa from different regions and countries have been conducted and summarized in differentiating tables.

Abstract

The Central Anatolian vegetation has diverse site conditions and small-scale plant diversity. For this reason, identification of plant communities is important for understanding their ecology and nature conservation. This study aims to contribute the syntaxonomical classification of the Central Anatolian vegetation. The study area is situated among Güzelyurt, Narköy, and Bozköy (Niğde) in the east of Aksaray province of Central Anatolia in Turkey. The vegetation data were collected using the phytosociological method of Braun-Blanquet and classified using TWINSPAN. The ecological characteristics of the units were investigated with Detrended Correspondence Analysis. Three new plant associations were described in the study. The steppe association was included in Onobrychido armenae-Thymetalia leucostomi and Astragalo microcephali-Brometea tomentelli. The forest-steppe association was classified under Quercion anatolicae in Quercetea pubescentis. The riparian association is the first poplar-dominated one described in Turkey and, classified under Alno glutinosae-Populetea albae and its alliance Populion albae.

Abstract

Extensive tall-trunk orchards, an important element of the central European landscape since the Middle Ages, conserve potential for the future regarding their biodiversity, land use policy and agricultural value. For these reasons, extensive tall-trunk orchards are interesting with regard to nature conservation. Once the management of these low-productivity vegetation sites ceases, the habitat is threatened by successive overgrowth by shrub vegetation. Taking abandoned tall-trunk cherry orchards with dry/mesophilous grassland undergrowth in the locality of Kaňk as an example, the degree of colonization of orchards by woody species and differences in the structure of vegetation cover in different periods after abandonment were monitored. The results showed that the cover of cherry trees in orchards abandoned before 1990 was approximately 30% lower than in orchards abandoned after 2000. The cover of the herb layer in orchards abandoned before 1990 was approximately 60% lower than in orchards abandoned after 2000. The species diversity of orchards abandoned before 1990 was statistically significantly lower than that of orchards abandoned after 2000. The total cover of all species in habitat in areas of medieval ore extraction was approximately 50% lower than that in land originally used for farming.

Abstract

The impact of regulated drip-irrigation on productivity and fruit quality of tomato ‘Tofane’ has been studied under a warm dry desert climate in southern Algeria. Yield, fruit weight and size, water content and parameters of fruit quality – total soluble solids, phenolic compounds, carotenoids, vitamin C, pH and titratable acidity were determined. Two irrigation treatments were applied in 2012 and 2013: T1, optimal irrigation (100% evapotranspiration – ETc) during the whole growth period (growth stages I, II and III); T2, optimal irrigation during I and II stages, and regulated deficit irrigation (67% ETc) during stage III (from fruit set to full fruit maturity of first and second bunch). T1 treatment during the whole season showed the highest values of soil water potential (Ψsoil), between −0.02 MPa and −0.06 MPa, on depths of 0.3 and 0.6 m, respectively. During stage III, regulated deficit irrigation caused the lowest Ψsoil values, which were between −0.1 MPa and −0.12 MPa on a soil depth of 0.3 and 0.6 m, respectively. Deficit irrigation caused significant decrease of water content in fruits and not significant decrease of fruit weight and size, as well as fruit yield while water saving for irrigation amounted to 10%. Comfort-irrigated tomato plants produced fruits containing significantly higher titratable acidity, total soluble solids and vit. C content. There was a tendency to decrease carotenoid content and increase phenolic content in both years of the study. Due to the possibility of water saving with not significant yield decrease, it seems that the reduction of water use in growth stage III would be an adequate strategy for tomato cultivation in hot, dry climate.

Abstract

A total of 558 specimens of black-bellied anglerfish Lophius budegassa (Spinola, 1807) were collected by the vessels engaged in commercial trawl fishing in the Central Aegean Sea between September 2017 and August 2018 in order to determine age and growth. Ageing was based on growth ring counts of transverse sections of the illicium (first ray of the dorsal fin). By reading the illicium, individuals were found within II-XI age groups. Total lengths and weights ranged between 12.0 – 65.0 cm and 24.5 – 4682.0 g, respectively. Von Bertalanffy growth parameters were estimated for males, females and combined sexes of L. budegassa. The results are compared with previous studies.

Abstract

The properties of biomass-based fuel and combustion tests showed that logging residues are promising renewable energy sources. The data used in this study were collected from four clear-felling areas in Järvselja Training and Experimental Forest Centre, Southeast Estonia in 2013–2014. Logging was carried out by harvesters in Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies [L.] Karst.), silver birch (Betula pendula Roth.) and black alder (Alnus glutinosa L. Gaertn.) dominated stands with a small admixture of other tree species according to the cut-to-length method and logging residues were placed in heaps. The aim of this research is to assess different characteristics of logging residues (quantity, moisture content, energetic potential, ash content and amount) in clear-felling areas. The highest load of slash was measured on the birch dominated study site, where the dry weight of the logging residues was 29 t ha−1. Only the branch fraction moisture content on the black alder dominated site (35.4%) was clearly different from respective values on other sites (21.6–25.4%). The highest calorific value of the residues was assessed with the residues from the birch dominated site, where in moist sample it was 365 GJ ha−1 and in dry matter 585 GJ ha−1. The heating value of the fresh residues is highest in coniferous trees. The highest ash content in branch segments was registered for the black alder dominated site. Järvselja data indicate higher quality in conifer dominated sites, yet a higher load of logging residues in broadleaf dominated stands.

Abstract

This study focused on the occurrence of xylophagous beetles and nematodes in the different parts of Pinus sylvestris L. trees of different health condition in the pure stands in Zhytomyr region (Central Polissya). Stem fragments with thin, thick and transitional bark, branches and twigs were examined in each of 12 model trees. Xylophagous beetles were identified by adults or by galleries. Nematodes were isolated from wood samples in the laboratory using the Baermann method and identified by morphometric characteristics. Among 10 species of xylophagous beetles, Ips acuminatus (frequency 16.7%; dominance 17.9%) and I. sexdentatus (frequency 11.1%, dominance 54.6%) dominated, which prefer the fragments with thin and thick bark respectively. No xylophagous beetle was found in the healthy and slightly weakened trees. Among 15 nematode species, 40% were saproxylic, 33.3% entomophilic, 13.3% phytophagous, and by 6.7% predators and species associated with fungi. An entomophilic nematodes Cryptaphelenchus macrogaster f. acuminati was common in all parts of stem and branches (frequency of occurrence 25–33.3%). An entomophilic nematodes Parasitorhabditis acuminati and a predator Fuchsia buetschlii acuminati had the highest frequency of occurrence (41.7%) under the thin bark and in the branches. The frequency of these species in colonized with xylophagous insects stem fragments with thin bark was significantly higher than in respective not colonized fragments.