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  • Open access
  • 81 Reads
Limnological Characteristics and Diatoms in Lakes of North-Eastern Poland

Determination of the relationships between environmental factors and diatom assemblages is usually made for several hundred lakes spread over a large area. However the analysis of several lakes located near Lake Wigry also gives interesting results. Lakes in Wigry National Park (Poland) with broad similarity of geological origin show clear limnological, physical, and chemical differences. We report analysis of how these dissimilarities influence diatom assemblages. Unsupervised machine learning using Hierarchical Cluster Analysis showed that the studied lakes can be divided into three groups: (1) disharmonic, (2) harmonious with greater human impact on the environment, and (3) harmonious with a more limited human impact. In the dysharmonic group, the most distinctive dominant species was Tabellaria flocculosa, accompanied by Eunotia mucophila, E. rhomboidea, Stauroforma exiguiformis, Nitzschia gracilis as most frequent codominants. Harmonic lakes were dominated by Achnanthidium minutissimum and Encyonopsis microcephala. Most frequent codominant species were Fragilaria subconstricta, Brachysira microcephala, Encyonopsis cesatii and Eunotia arcubus. Studied lakes were abound in rare species such as Gomphonema vibrio, Fragilaria subconstricta, Aneumastus balticus, Navicula praeterita, N. subalpina or Sellaphora bacillum. The three groups vary in dominance structures, as reference to the Dominance Index (DI) made clear (mean values being: (1) −70.54%, (2) −72%, and (3) −54.58%, Generalized Linear Models with the categorical independent variable (group) showed significant differences between groups (for 1–3, 2–3) p value < 0.05). Lakes influenced by anthropopressure and disharmonic ones had the strongest dominance structure. DI differences between the groups are consistent with the Species Pool Hypothesis (SPH), while studied differences can be said to result from natural geological dissimilarities, as well as disparate anthropogenic impacts.

  • Open access
  • 95 Reads
Punica granatum l. Fruit Parts from Algerian Cultivar Bioactive Compounds and In Vitro Biological Activities: A Comparative Study

Fruits are a source of antioxidant compounds, such as phenolics, vitamins and carotenoids, which contribute to their chemo preventive potential. The mentioned compounds, which scavenge free radicals, may reduce the level of oxidative stress and prevent the oxidation of biomolecules, that would break the reaction chains of pathogenesis in the deterioration of physiological functions, which could occur in the coronary heart diseases and cancer [1]. Apart from their biological properties, natural antioxidants are also of interest in the cosmetic, pharmaceutical and especially in food industries, since they can be also used as natural antioxidants, Nutraceuticals, prebiotics, dyes. [2]

The present work evaluated phenolics, and flavonoids contents (quantity) of organic pomegranate juice, peel and seeds cultivated in the Northeastern part of Algeria, in vitro antioxidant activity, using: CUPRAC, GOR, PHENYL, DPPH, ABTS assays and enzymatic activity: α-glycosidase were also investigated and confirms traditional uses of pomegranate parts[3]. Furthermore, a comparative study of all these essays on different pomegranate's parts tests will be given.

However, further investigations should assessed safety of by products "seeds, arils and peels" at efficient but non toxic doses, if we want to use it as added value in our daily feeding .

  • Open access
  • 81 Reads
Impact of Flora Communities on Nutrients Dynamics in Hyporheic Zone of Urban Spring Ecosystem

Hyporheic zone (HZ) is an interstitial part of groundwater that can provide a spectrum of subsurface habitats depending on the spatial distribution of upwelling groundwater. Differentiation of environmental factors affects the abundance and distribution of plants associated with outflows of groundwater. Plant communities in spring niches dependence on permanent, relatively cold water that not freeze in winter. High dynamics of redox conditions and low temperature increase the intensity of nitrification, denitrification and ammonification processes. We hypothesized that groundwater upwelling enrich surface water with biogenic compounds, and it depends on among others the flora communities. Research were conducted in two lowland spring niches, its outflows and two rivers in suburbs of Bialystok (Poland). Interstitial samples were collected with mini-piezometers. Nutrient analysis were conducted using chromatographic methods, organic carbon analyser and Kjeldahl analyser. The analysis of flora included: vascular plants and bryophytes. The highest concentration of nutrients was recorded in rivers, which results from the catchment inflow. In interstitial waters of both springs, high concentration of ammonium and nitrate ions was recorded compared to their content in the outflow. Hydrophilic vegetation performs a stabilizing function by assimilating nitrogen compounds and contributing to a variations in nutrients concentration. In total, 19 species of vascular plants, 5 mosses and 1 liverwort were recorded. The springs differed in their richness of species, depending degree of human impact. Brachytecium rivulare, whose presence was recorded, is considered a bioindicator of oligotrophy and mesotrophy. The presence of protected species Nasturtium officinale indicates a high degree of naturalness of the environment. Plant community richness can be a good indicator of the ecological status of lowland springs.

  • Open access
  • 318 Reads
Investigating the Diversity of the Terrestrial Invertebrate Fauna of Antarctica: A Closer Look at the Stereotydeus (Acari: Prostigmata) Genus †

The extremely inhospitable Antarctic ecosystems confines plants and invertebrates to sparse ice-free areas. These species survived for millions of years in isolated refugia where population divergence and differentiation can occur, potentially resulting in speciation. The limited dispersal abilities of invertebrate species combined with their specific habitat requirements and the substantial geographical barriers can drastically reduce the gene flow between different populations, resulting in high genetic differentiation between clusters of individuals. With more than 100 described species, mites are surely the most diverse invertebrate group of Continental Antarctica. Among them, the free-living genus Stereotydeus Berlese, 1901 (Acari: Prostigmata) is represented by 6 Antarctic species of which 5 occur along the coastal zones of Victoria Land and the Transantarctic Mountains. In order to examine the biodiversity and the phylogeographic distribution ranges of Stereotydeus spp. across Victoria Land, we conducted an integrated analysis of the genus through morphological, phylogenetic and population genetics studies. Specimens were collected from nine localities in Victoria Land and sequenced for the cytochrome c oxidase subunit I mitochondrial gene (COI) and a fragment of the 28S ribosomal RNA-encoding gene using mite specific primers. We morphologically identified and described two novel Stereotydeus species from central and south Victoria Land. While the relationships between the cox1 haplotypes from North Victoria Land are well defined, the distribution of the central-southern species appears more complex. This suggests a possible common evolutionary history in a number of isolated glacial refugia, with scarce gene flow even within populations probably resulting from inter/intra-specific events influenced by several abiotic/biotic factors. Recent threats to Antarctic biodiversity like accelerated climate change, pollution, biological invasions and the increase of human activities have caused increased calls for adequate conservation measures. Establishing a new distribution map for the Stereotydeus species of Victoria Land may help lay the foundations for future decisions in matters of protection and conservation of the unique terrestrial fauna of Antarctica.

  • Open access
  • 179 Reads
Can Species Distributions Models Help to Design Conservation Strategies for Narrow-Ranged Species under Climate Change? A Case Study from Santolina Genus

Climate change is dramatically threatening biodiversity. Narrowly distributed species are especially exposed to extinction risk due to their narrow ecological niche. We used Species Distribution Models at fine spatial resolution (50m) to investigate changes in the distribution of three range-restricted species of Santolina endemic to the Mediterranean Basin (S. decumbens, S. ligustica, S. pinnata). We assessed the future potential range under an optimistic and a pessimistic scenario, and analysed distribution change taking into account three different ranges: the distributional range (calculated as convex hull), an area 5 km larger than the distributional range, and a buffer (1 km) around occurrences. Santolina ligustica is expected to dramatically reduce its range under both scenarios, Santolina decumbens is expected to increase its range under both scenarios and Santolina pinnata is expected to dramatically reduce its range under the pessimistic scenario and to increase it under the optimistic one. Moreover, in the optimistic scenario, S. ligustica and S. pinnata show a very high range loss in all areas but the range gain is higher in the largest area than in the other two areas. This result suggests that, in the future, suitable areas will occur mainly outside of the current distributional range and that assisted colonization may be necessary to assure species survival. Differently, the third species has a lower range loss and higher range gain within the distributional range and in the buffer around occurrences, suggesting the possibility of survival in microrefugia within its distributional range despite a wide reduction in suitable habitat. These results might help to design strategies for species conservation in face of future climate change.

  • Open access
  • 108 Reads
Sequence-Related Amplified Polymorphism (SRAP) Markers: A Feasible Tool for Studies in Invasion Genetics of Freshwater Fish

Molecular tools can effectively be used in diagnosis, identification, management, and most especially detection of invasion pathways and originations of introduced species. It can provide helpful information for a better conception of the events that are essential for successful colonization by comparing genetic differentiations of a species within its native and invasive habitats. PCR-based dominant marker techniques, such as RAPD, AFLP and ISSR have been used for studying genetic diversity, taxonomy and phylogeny of the species, but they generally are used for estimating more limited levels of genetic variation. Despite the potential of these molecular markers to generate helpful data, researchers have been suspicious about using them resulting from technical deliminations. A more recently developed molecular marker system, Sequence-Related Amplified Polymorphism (SRAP) is an easy, reliable, middle-yield, high-dominant total, and iterative way to detect genetic variation of different species. SRAP markers were essentially created for molecular tagging in wild cabbage to particularly amplify coding regions of the genome. It also has been used in analyses of genetic variation and population genetics of several species such as fungi and nematodes. Like other dominant markers, SRAPs can also be used for assessing invasion genetics of non-native species nd their use to discover variations in genetic structure of native and invasive freshwater fish has been becoming common. Based on the rapidly growing body of literature, we suggest that SRAPs could, and should, be applied to study invasion genetics. The aim of this study was to identify the potential for SRAP markers in invasion genetics of freshwater fish. Results from SRAP products may prove to be significant for discovering polymorphisms and genetic variations in studying population genetics of invasive species.

  • Open access
  • 113 Reads
Exudate Compounds of Origanum Species

Exudate flavonoids and their distribution among the plant kingdom have been comprehensive studied by Prof. Eckhard Wollenweber and the followers of this approach for analysis. In addition to being taxonomically important, these compounds have important ecological functions due to their location on the surface on plant. Exudate flavonoids often are defined as a surface, external and lipophilic. Besides flavonoid aglycones in the exudate are contained also terpenes, fatty alcohols and acids, alkanes, phenolic acids. Origanum species are valuable medicinal and culinary herbs, more that their biocidal activity is very important in the last decades. The results of the research on allelopathic interactions are scientific basis for selection of plant products with biocidal properties. The first substances involved in these interactions in nature are the exudate (surface) compounds.In the present study, acetone exudates of ten samples of Origanum species were comparatively analyzed by GC/MS and HPTLC. Plant material of Origanum dictamnus L., Origanum vulgare L. and Origanum vulgare subsp. hirtum (Greek oregano) as the latter taxa was represented by 8 patterns with different origin were studied. Flavonoid aglycones, mono- di- triterpenes, fatty acids and alcohols, alkanes, phenolic acids and derivatives were identified. Methylated derivatives of flavones – apigenin and luteolin were identified as the most common flavonoid aglycones. The most complex flavonoid profile was detected for O. vulgare ssp hirtum samples. A few differences in the flavonoid profiles of O. vulgare ssp hirtum from different origin of were found. Carvacrol (monoterpene phenol) was determined as main component of Origanum vulgare subsp. hirtum samples, in O. dictamnus exudate sesquiterpenes were detected in addition whereas in O. vulgaris exudate long-chain fatty alcohol and alkanes were found as abundant compounds. Differences observed between studied taxa as well as among the examined samples of O. vulgare ssp hirtum were discussed. The data obtained complement the knowledge of the distribution and role of exudate compounds.

Acknowledgements: This research was supported by the Bulgarian National Science Fund, Bulgarian Ministry of Education and Science (Grant DN 16/2, 11.12.2017).

  • Open access
  • 86 Reads
Overlapping Areas of Non-Indigenous and Critically Endangered Freshwater Fishes: Setting Conservation Priorities in Greece

The introduction of non-indigenous fish species (NIFS) to freshwater ecosystems is considered as one of the leading factors associated with freshwater biodiversity loss. Unravelling the spatial overlap between NIFS and critically endangered (CR) fish species can contribute to targeted conservation planning and actions to minimize the potential negative effects. In this study, we applied a geostatistical analysis of species distribution data to investigate the potential overlapping areas of NIFS against fish species that are designated under a CR status according to the International Union for the Conservation of Nature (IUCN) and the Hellenic Zoological Society (HZS) Red Lists. Distributional (presence–absence) data of all NIFS were compiled for both lentic and lotic ecosystems of Greece. In total, 800 sites were utilized from 169 lakes and 631 river sites from 51 river basins. Our results indicate that freshwater ecosystems under high NIFS richness are located mainly in lowland areas of western, central and northern Greece usually near large cities and ecosystems with high commercial and recreational fisheries. On the contrary, low NIFS richness was observed in mountainous regions and small river basins. Overlapping areas of CR species with moderate to high NIFS richness (1.5-4.3 NIFS per 1 km2) were relatively high (~50%). Many of the overlapping areas fall well within NATURA 2000 network, where legal management bodies can implement management programs to minimize the negative impacts. However, some areas of conflict are in unprotected zones and may be likely to experience significant negative biodiversity impacts. The use of the CR status is useful as a proxy indicator for some of Greece's most important inland water ecosystems in order to avoid new invasions and to manage established alien and translocated species. Our findings demonstrate that many freshwater ecosystems in Greece are under significant invasion pressure and also exhibit high biodiversity conservation value.

  • Open access
  • 152 Reads
Inhabitants of the Heights: An Anthropological Perspective on the Selection of Sleeping Sites of Brachyteles arachnoides

Brachyteles arachnoides or better known as the southern muriqui is critically endangered due to the high fragmentation of the Atlantic Forest. During the months of September and October of the year 2018, a systematic observation was made in the Carlos Botelho State Park, San Miguel de Arcanjo, Brazil aimed at the identification and ecological characterization of the sleeping sites, taking into account the physiological characteristics of the trees used by the muriqui to spend the night.

The sleeping sites (n=10) are located in a semi-deciduous forest with a high variety of tree species. The data obtained from these trees indicate that on average they reach 20 meters, with the preferred height for sleeping between 11 and 14 meters. This is accompanied by the choice of spaces located on slopes with rivers, great connectivity between trees and quick access to food.

The results obtained have allowed us to contemplate on the importance of the concept of territory and home within the community development of southern muriqui. On the other hand, this research aims to generate a reflection on the politicization of conservation efforts of of non-human bodies, to achieve a harmonious and horizontal development between human and non-human populations.

  • Open access
  • 143 Reads
Use of Dunaliella salina in Environmental Applications

Macro and microalgae are widely used in environmental and biotechnological applications due to their unique natural properties. Algae groups are aquatic organisms that can be found in many parts of the world and vary in size from 3-10 μ to 70 cm. Algae are divided into two as prokaryotic (microalgae) and eukaryotic (macroalgae) according to their biological formations. "Cyanophyta" as microalgae and "Phaeophyta, Rhodophyta, Chlorophyta, Flagelleta" as macro algae are known. Dunaliella salina is a living thing that can live in saltwater ecosystems and belong to the microgreen algae group. Since these algae are a natural source of beta-carotene, they are of particular importance in the cosmetics and food industries compared to other green microalgae species. Almost all algae groups are used for different purposes in a wide variety of sectors. Dunaliella spp. types are used extensively in areas such as the energy sector (bio fuel), cosmetics, medical applications, bioplastic production, wastewater treatment, food industry. In addition, the most basic effect parameter of pink color formation in lakes with salt content due to seasonal changes is Dunaliella salina, which is not an environmental problem. Increasing environmental pollution, unconscious energy consumption, and climate change have led countries to seek alternative solutions to environmental issues and to develop environmentally friendly-technological methods. For sustainable environmental management and minimization of pollution; The benefits of using algae species have been demonstrated by different applications. In the literature, Dunaliella salina has focused on algae production and the use of pigments in the cosmetics and food industry. The aim of this study is to investigate the recent researches on Dunaliella salina and reveal the importance of this algae, especially in terms of sustainable environment and energy.

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