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Contribution to the knowledge of Crataego-Prunetea Tüxen 1962 class in Bulgaria

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.

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Echinophora spinosa L. (Apiaceae), a new species in the flora of Tunisia and second report from North Africa

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.

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Phytosociological analysis of basophilic Scots pine forests in the Southeastern Alps

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.

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Phytosociological study of the forest vegetation of Kyiv urban area (Ukraine)

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.

Open access
The phytosociology, ecology, and plant diversity of new plant communities in Central Anatolia (Turkey)

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.

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Vegetation succession in extensive abandoned tall-trunk cherry orchards: a case study on Kaňk Mountain near Kutná Hora (Czech Republic)

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.

Open access
Histochemical Staining of Acetylcholinesterase in Carnolian Honeybee (Apis mellifera carnica) Brain after Chronic Exposure to Organophosphate Diazinon

Abstract

Organophosphate insecticides are known to inhibit the activity of enzyme acetylcholinesterase. They affect olfactory learning and memory formation in honeybees. These insecticides cause mushroom body inactivation in honeybees, but their influence on other brain regions involved in olfactory perception and memory is unknown. The goal of this study was to study the effects of organophosphate insecticide diazinon on carnolian honeybee (Apis mellifera carnica) acetylcholinesterase activity in the olfactory brain regions of antennal lobe, mushroom body and lateral procerebrum (lateral horn). The lamina, medulla and lobula of optic lobes were also analyzed. The level of acetylcholinesterase activity was visualized using the histochemical staining method. Densitometric analysis of histochemical signals indicated that diazinon inhibited acetylcholinesterase activity only in the lip of calyces of mushroom body, but not in other analyzed olfactory regions, antennal lobe and lateral procerebrum. The visual brain system optic lobes were also unaffected. This is in accordance with the literature reporting that mushroom body is the main brain center for olfactory learning and memory formation in honeybees.

Open access
A Modified Standardized Method to Extract and Store Insect Hemolymph with Use of a Glass Capillary

Abstract

Hemolymph is the “blood” circulating in the entire insect body. Analysis of this fluid gives information about the condition of the insect. The most precise analyses are conducted on insects’ hemolymph suspended in 0.6% physiological saline (NaCl). Most current hemolymph extraction methods are either difficult or do not provide pure material, the contamination of collected insect “blood” can change results. This study aimed to develop a technique for extract hemolymph, both easy and without risk of contaminating derived material. The presented method is a modification of available ways to extract, store and transport hemolymph with the use of a glass capillary. For the development of this technique, adult worker honey bees (Apis mellifera L.) were used. The method required such basic equipment as a glass capillary, sterile tweezer, Eppendorf tube and physiological saline. The collected hemolymph were frozen and hence sent in a glass capillary to another laboratory for analysis.

Open access
Optimization of Protein Feed Fermentation Process for Supplementation of Apis Mellifera Honeybees

Abstract

An alternative to natural food shortage for honeybees is the provision of supplements. The objective of this research was to develop a method with ideal conditions for the fermentation of a protein supplement for honeybees. The microorganisms used were Lactobacilli, Bifidobacteria and Saccharomyces and the inulin prebiotic. There was an increase in lactic acid and a decrease in pH over a five-day fermentation period. The amount of acid bacteria present was 108–109 CFU/g of supplement. In the first phase the temperature and the humidity had significantly affected the fermentation but the variables inulin and probiotic didn’t. In the second phase, the lower temperatures and higher humidity produced the best effects on the fermentative responses. It was concluded that an ideal environment with temperature, humidity, inulin and probiotics could be created which allowed the fermentation of the protein supplement in five days obtaining final product fermentative characteristics close to bee bread.

Open access
Prospects and Validity of Laboratory Cage Tests Conducted in Honeybee Research Part Two: New Possibilities for Use of Laboratory Cage Tests in Response to Challenges Revealed at the Turn of the 20th and 21st Centuries

Abstract

Nowadays, cell cultures are a standard tool in animal biotechnology, but the problem with honeybees is the constant lack of appropriate cell lines to be used in in vitro research. Until the imperfections of bee tissue cultures are resolved, researchers have to conduct experiments on bees in laboratory cage tests (LCTs).

At the turn of the 21st century many new hazards for beekeeping appeared. An early recognized problem was the Colony Collapse Disorder and Honey Bee Depopulation Syndrome, which were associated with the harmfulness of pesticides and strictly linked with a decline in bee immunity. Such problems in LCTs were attempted to be resolved through research on the interactions between biostimulators and antiparasitic drugs. LCTs allow the relationship between the dose of a specific factor and its impact to be determined, which can be used in the establishment of reference values. Furthermore, LCTs may be a useful tool in understanding the function and role of bee gut flora.

Using the honeybee as an animal model is possible thanks to knowledge of the honeybee genome and bee biology and the similarity between some physiological and biochemical processes and those occurring in humans. So far, LCTs have been used to understand better human aging, learning and gene expression regulating. This is facilitated by the advanced development of medicine and molecular genetics, and in the future the use of honeybees may become a standard in biochemical or gerontological research.

Open access