scholarly journals Meiofaunal Dynamics and Heterogeneity along Salinity and Trophic Gradients in a Mediterranean Transitional System

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1488 ◽  
Author(s):  
Federica Semprucci ◽  
Maria Flavia Gravina ◽  
Paolo Magni
Keyword(s):  
Habitat Heterogeneity ◽  
Environmental Variability ◽  
Assemblage Structure ◽  
Spatiotemporal Variation ◽  
Transitional Waters ◽  
Study Sites ◽  
Number Of Individuals ◽  
First Time ◽  
Transitional System ◽  
Trophic Gradients

The spatiotemporal variation in meiofaunal assemblages were investigated for the first time in the Cabras Lagoon, the largest transitional system in the Sardinian Island (W-Mediterranean Sea). Two main environmental (salinity and trophic) gradients highlighted a significant separation of the three study sites across the lagoon, which were consistent through time. The environmental variability and habitat heterogeneity of the Cabras Lagoon influenced the meiofauna. In particular, salinity and dissolved oxygen, primarily, shaped the meiofaunal assemblage structure at the seaward site which was significantly different from both the riverine and the organically enriched sites. On the other hand, the trophic components (e.g., organic matter, Chlorophyll-a, and phaeopigments) and the different degrees of confinement and saprobity among sites were the secondary factors contributing mostly to the separation between the latter two sites. The lack of significant differences in the temporal comparison of the meiofaunal assemblage structure along with the very low contribution of temperature to the meiofaunal ordination indicated that this assemblage was more affected by spatial rather than by temporal variation. This pattern was also supported by significant differences between the three sites in several univariate measures, including total number of individuals, number of taxa, Pielou’s evenness, and the ratio between nematodes and copepods. Thus, the present study corroborates the hypothesis that meiofaunal organisms are good indicators of the spatial heterogeneity in transitional waters (TWs) and could have a greater species richness than that expected. Indeed, the Cabras Lagoon overall showed one of the highest meiofaunal richness values found from both Mediterranean and European TWs.

scholarly journals ESTUDIO DEMOGRÁFICO DE Emilia sonchifolia (ASTERACEAE) EN UNA FINCA CAFETERA DE ARMENIA, QUINDÍO, COLOMBIA

2014 ◽  
Vol 20 (2) ◽  
Author(s):  
Irene Duarte Gandica ◽  
Maryam Chaib de Mares ◽  
David Andrés Luna ◽  
Oscar Alexander Aguirre-Obando ◽  
Rosa María Méndez Parra
Keyword(s):  
Logistic Model ◽  
Research Study ◽  
Life Stage ◽  
Coffee Plantation ◽  
Simulation Based ◽  
Coffee Farm ◽  
Number Of Leaves ◽  
Potential Strategy ◽  
Study Sites ◽  
Number Of Individuals

<p>Se realizó un estudio con el fin de determinar la estructura demográfica de <em>Emilia sonchifolia </em>(L.) DC<em> </em>en una finca cafetera del Municipio de Armenia, Quindío, Colombia, donde se recolectaron datos durante 4 semanas, en tres sitios: exterior, borde e interior del cultivo. Usando parámetros calculados a partir de los datos de campo, se construyó un modelo logístico para describir el comportamiento poblacional en el tiempo. Se encontraron diferencias significativas en las variables: número de individuos por estado etario en el tiempo, porcentaje de mortalidad, tiempo de cambio del estado plántula a juvenil y de juvenil a adulto, número de hojas y de ramas; no se encontraron diferencias significativas en la densidad poblacional, número de inflorescencias e infrutescencias en los sitios de estudio. En general, se puede atribuir este comportamiento a la estrategia de reproducción <em>r</em> que sigue <em>E. sonchifolia</em>. Finalmente, las simulaciones hechas a partir del modelo logístico sugieren que la especie tiende a desaparecer si alguno de los estados etarios no está presente inicialmente; así, una alternativa plausible para el control sería su eliminación en el estado juvenil. Los resultados ofrecen alternativas con respecto al manejo de<em> </em>poblaciones de arvenses.</p><p><strong>ABSTRACT</strong></p><p>A research study was conducted to determine the demographic structure of <em>Emilia sonchifolia</em> L. in a coffee plantation in Armenia, Quindío, Colombia. Data were collected over a period of four weeks on three sites: inside, at the border and outside a coffee farm. A logistic population model was built to describe the population behavior of <em>E. sonchifol</em><em>ia </em>over time. Statiscally significant differences were found between: number of individuals per life stage in time, mortality rate, transition time from seedling to juvenile and from juvenile to adult; and number of leaves and branches. There was no evidence for statistically significant differences in population density or in number of inflorescences and fruits between study sites. In general, the observed behavior may be attributed to the <em>r</em> strategy used by this species. Finally, our results suggest the survival of the species is conditioned by the presence of all life stages at the beginning of each simulation based on the logistic model; so, a potential strategy for its controlling would require the removal during the juvenile stage. The considerations offer alternatives regarding weed population management.  </p>

scholarly journals Experimental evidence for foraminiferal calcification under anoxia

2014 ◽  
Vol 11 (14) ◽  
pp. 4029-4038 ◽  
Author(s):  
M. P. Nardelli ◽  
C. Barras ◽  
E. Metzger ◽  
A. Mouret ◽  
H. L. Filipsson ◽  
...  
Keyword(s):  
Environmental Variability ◽  
Sediment Cores ◽  
Adult Mortality ◽  
Short Term ◽  
Essential Information ◽  
Ample Evidence ◽  
Anoxic Conditions ◽  
Inhibition Of Growth ◽  
Foraminiferal Species ◽  
First Time

Abstract. Benthic foraminiferal tests are widely used for paleoceanographic reconstructions from a range of different environments with varying dissolved oxygen concentrations in the bottom water. There is ample evidence that foraminifera can live in anoxic sediments. For some species, this is explained by a switch to facultative anaerobic metabolism (i.e. denitrification). Here we show for the first time that adult specimens of three benthic foraminiferal species are not only able to survive, but are also able to calcify under anoxic conditions, at various depths in the sediment, and with or without nitrates. In fact, several specimens of Ammonia tepida (1–4%), Bulimina marginata (8–24%) and Cassidulina laevigata (16–23%) were able to calcify at different redox fronts of sediment cores, under laboratory conditions. This demonstrates ongoing metabolic processes, even in micro-environments where denitrification is not possible. Earlier observations suggest that the disappearance of foraminiferal communities after prolonged anoxia is not due to instantaneous or strongly increased adult mortality. Here we show that it cannot be explained by an inhibition of growth through chamber addition either. Our observations of ongoing calcification under anoxic conditions mean that geochemical proxy data obtained from benthic foraminifera in settings experiencing intermittent anoxia have to be reconsidered. The analysis of whole single specimens or of their successive chambers may provide essential information about short-term environmental variability and/or the causes of anoxia.

scholarly journals Sternbergia colchiciflora Waldst. et Kit. (Amaryllidaceae), a new genus and species in the flora of Kosovo

2020 ◽  
Vol 79 (2) ◽  
pp. 236-238
Author(s):  
Xhavit Mala ◽  
Qenan Maxhuni
Keyword(s):  
New Genus ◽  
Critically Endangered ◽  
New Genus And Species ◽  
Limited Distribution ◽  
Number Of Individuals ◽  
First Time

This paper reports Sternbergia colchiciflora Waldst. et Kit. as a new genus and species for the flora of Kosovo. Almost 30 adult individuals of this species were recorded for the first time in southwestern Kosovo during 2015, within the Canyon of the White Drin at Fshajt Bridge. Considering the low number of individuals and very limited distribution, this species should be treated as a critically endangered taxon in Kosovo.

scholarly journals Reef Fishes Colonization Rate Around Artificial Reef in Putus-putus Island, South-East Minahasa District

2017 ◽  
Vol 5 (1) ◽  
pp. 21
Author(s):  
Laurentius T. X. Lalamentik ◽  
Unstain N. W. J. Rembet ◽  
Adnan S. Wantasen
Keyword(s):  
Reef Fish ◽  
Fish Species ◽  
Research Effort ◽  
Artificial Reef ◽  
Environmental Parameters ◽  
Reef Fishes ◽  
Artificial Reefs ◽  
Colonization Rate ◽  
Study Sites ◽  
Number Of Individuals

A comprehensive research effort was directed to increase the ecological role of Putus-Putus island coral reefs. This study was an implementation of artificial reef technology as fish colonization locality. The artificial reefs were made of 20x20x100 cm-concrete blocks placed in 6 levels and located at the depth of 8-10 m. Reef fish observations were done three times in two locations. Environmental parameters, such as temperature, salinity and visibility, were also measured. Environmental parameters (temperature, salinity a. Water temperature (29.65oC and 29.64oC) supported the coral growth as well. Salinity distribution  was not significantly different among the study sites.  This study also found 37 reef fish species belonging to 18 families. Number of species varied with observed time and localities. Total number of individuals increased with number of fish species. Mean number of individuals and species of reef fish in locality B were higher than those in locality A. Moreover, the reef fish colonization rate in the study site followed the model y = 4.3801e0.5249x with R2= 0.9297 in the strait and y = 5.0397e0.5493x  with R2= 0.9297 for the Bay. Keywords: Artificial reefs, reef fish. Abstrak Suatu upaya penelitian yang komprehensif diarahkan untuk peningkatan fungsi ekologi terumbu karang Pulau Putus-Putus. Penelitian ini berupa penerapan teknologi terumbu buatan sebagai tempat hunian ikan. Terumbu buatan terbuat dari balok cor beton berukuran 20x20x100 cm bersusun 6 dan ditempatkan pada kedalaman 8-10 m. Pengamatan ikan karang dilakukan 3 kali di 2 lokasi berbeda. Parameter lingkungan, seperti suhu, salinitas, dan kecerahan, juga diukur.    Hasil pengukuran yang diperoleh (29,65 oC dan 29,64 oC) termasuk suhu yang optimal untuk pertumbuhan karang. Dari hasil penelitian, ditemukan 37 spesies yang masuk dalam 18 famili ikan karang. Jumlah spesies yang ditemukan bervariasi pada setiap waktu dan lokasi pengamatan. Pengambilan spesies ikan karang dilakukan pada 2 lokasi dengan masing-masing lokasi dilakukan 3 kali pengambilan sampel. Berdasarkan hasil yang diperoleh (tabel 03) dapat dilihat bahwa jumlah individu bertambah seiring dengan banyaknya jumlah spesies ikan karang yang didapat. Rata-rata jumlah individu dan jumlah spesies ikan karang pada lokasi B lebih banyak. Laju hunian ikan karang di lokasi penelitian mengikuti model y = 4.3801e0.5249x dengan R2= 0,9297 untuk lokasi Selat dan y = 5.0397e0.5493x  dengan R2= 0,9297 untuk lokasi Teluk. Kata kunci : Terumbu buatan, ikan karang

scholarly journals Abundance and Distribution of Odonates (Dragonflies and Damselflies) In Akwa Ibom State, Nigeria

2018 ◽  
Vol 1 (1) ◽  
pp. 33-38
Author(s):  
Kehinde A. Kemabonta ◽  
Rosemary Essien ◽  
Babasola W. Adu ◽  
Sylvester U. Ogbogu ◽  
Abdussalam Iysa ◽  
...  
Keyword(s):  
Species Diversity ◽  
Statistical Difference ◽  
Habitat Degradation ◽  
Anthropogenic Activities ◽  
Ongoing Research ◽  
Management Techniques ◽  
Study Sites ◽  
Abundance And Distribution ◽  
Number Of Individuals ◽  
Sweep Net

Introduction: Odonates are used as bio-indicators for monitoring habitat degradation both on terrestrial and aquatic ecosystem because of their sensitivity to anthropogenic activities. They serve an important role in the ecological food chain by consuming aquatic larvae and being in turn consumed by birds and various amphibians. This study is part of the ongoing research on the diversity of Odonate species of Nigeria. The objective is to determine the abundance and distribution of odonates in Akwa Ibom State and to compare the species diversity across the various sites in Akwa Ibom State. Methodology: Akwa Ibom state was divided into six areas namely Ikot Akpaden, Obio Akpa, Ikot Okoro, Ikot Udofia, Urua Udofia and Obio Ndot using biotypes and a study site was randomly selected in each area. Adult members were captured using a sweep net and were preserved for identification using morphological features. Results: A total of 767 odonates were collected at the six study sites representing 24 species, 16 genera and four families namely Libellulidae (77%), Coenagrionidae (21%), Calopterygidae (>1%) and Chlorocyphidae (>1%). Most of the species collected were members of family Libellullidae (77%) with Palpopleura lucia having the highest occurrence (41%) and found in all the sites. Family Calopterygidae and Chlorocyphidae had less than 1% population of the total individuals collected. Ikot Okoro had the highest number of individuals (238) and the least evenness (e^H/S=0.3292) while Ikot Akpaden, which had the least effect of anthropogenic intrusion had the largest diversity of Odonata species (H’=2.387). Obio Ndot had the most evenly distributed Odonata species (e^H/S=0.8028). There was no statistical difference in the occurrence of dragonflies across all study sites (p= 0.238). Conclusion: The high occurrence of family Libellulidae which are anthropogenic tolerant, and the absence of more highly localized species indicate that most of the study sites have been degraded and may not be fit for species with narrow niches. It is therefore vital to conserve the Odonata community by implementing proper forest management techniques.

scholarly journals Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables

2014 ◽  
Author(s):  
Liliana B Falco ◽  
Rosana V Sandler ◽  
Fernando R Momo ◽  
César A Di Ciocco ◽  
Leonardo A Saravia ◽  
...  
Keyword(s):  
Enzymatic Activity ◽  
Soil Properties ◽  
Environmental Variability ◽  
Species Abundance ◽  
Cattle Grazing ◽  
Low Ph ◽  
Assemblage Structure ◽  
Agricultural System ◽  
Mechanical Resistance ◽  
Aporrectodea Caliginosa

The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological variables that are associated to the observed differences in earthworm assemblage structure between soils. Three soil uses were evaluated: 1- Fifty year old naturalized grasslands; 2- Cattle-grazing fields converted to feedlot within the two years before the start of this work, and 3- Fifty year old intensive agricultural fields. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in their relative abundances according to the system. The results show that earthworm community structure is linked to and modulated by soil properties. Both, species abundance and diversity showed significant differences depending on soil use intensity. A PCA analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance Systems. Microscolex dubius was shown to be related to the naturalized grasslands and it was associated to Ca, pH, Mechanical Resistance, and to respiration. Aporrectodea caliginosa was related to high K levels, low enzymatic activity, slightly low pH, and low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found un the cattle-grazing system, were related to high soil humidity, low pH, low Ca and low enzymatic activity. These results show that earthworm assamblages can be good descriptors of different soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea, showed different temporal patterns and species associations, due to the changes in soil properties attributable tos oil use intensity.

scholarly journals A Behaviour Sequence Analysis of Young People and Gambling-Related Harm

2019 ◽  
Vol 43 ◽  
Author(s):  
David Keatley ◽  
Adrian Parke ◽  
Ellen Townsend ◽  
Claire Markham ◽  
David Clarke
Keyword(s):  
Sequence Analysis ◽  
Young People ◽  
Life Histories ◽  
Future Research ◽  
Gambling Behaviour ◽  
Pathway Models ◽  
Novel Method ◽  
Number Of Individuals ◽  
First Time ◽  
Related Harm

Gambling is a worldwide issue that requires continued, extensive investigation. Most people have gambled at some point in their lives, and many do so without incurring problems. However, a number of individuals do experience gambling-related harm, and understanding the pathways or life histories these individuals have experienced may elucidate how and why their gambling became harmful. The current research uses a novel method, Behaviour Sequence Analysis, to understand the temporal pathways that young people experience when first gambling. Behaviour Sequence Analysis takes multiple qualitative accounts, first-person interviews in the current study, and collates the data into statistical pathway models that show the chains between behaviours and events. A sample of 66 participants provided details of their life experiences regarding what led them to first gamble. Results indicated that parents and peers had a large influence and were facilitators in the first-time gambling episode, which was expected. However, the results also showed that many participants suggested that receiving scratch cards in their birthday cards was their first experience of gambling, and this seemingly innocuous act was the first step towards a pathway into gambling-related harm. The findings, therefore, support previous literature, while highlighting a novel method for future research, and various key intervention points for which strategies could be developed to reduce the potential for developing gambling-related harm behaviours.RésuméLes jeux de hasard constituent un problème mondial qui nécessite des études approfondies et continues. La plupart des gens ont joué à un moment de leur vie et beaucoup le font sans problème. Cependant, un certain nombre de personnes subissent des préjudices liés au jeu. Comprendre les parcours ou les histoires de vie de ces personnes peut expliquer comment et pourquoi leur jeu est devenu préjudiciable. Les recherches actuelles utilisent une méthode innovante, la Behaviour Sequence Analysis (analyse séquentielle de comportement) pour comprendre les parcours temporels qu’empruntent les jeunes lorsqu’ils commencent à jouer. Cette forme d’analyse séquentielle se fonde sur plusieurs analyses qualitatives et des entretiens à la première personne, et les données sont regroupées dans des modèles de parcours statistique qui mettent en évidence les liens entre les comportements et les événements. Soixante-six participants ont fourni des détails sur leur première expérience de jeu et sur ce qui les a amenés à jouer la première fois. Les résultats indiquent que les parents et les pairs ont une grande influence sur le premier épisode de jeu, ce à quoi l’on s’attendait. Cependant, les résultats montrent également que de nombreux participants ont indiqué que des cartes à gratter en guise de cadeau d’anniversaire étaient leur première expérience de jeu, et que cet acte apparemment anodin était le premier pas dans une voie menant à une dépendance au jeu. Les résultats corroborent donc la littérature antérieure, tout en soulignant une méthode innovante pour les recherches futures et divers points d’intervention clé pour lesquels des stratégies pourraient être élaborées afin de réduire le potentiel de développement de comportements préjudiciables liés au jeu.

scholarly journals New records of vascular plants in the West Altai

Turczaninowia ◽  
2021 ◽  
Vol 24 (4) ◽  
pp. 131-139
Author(s):  
Sergey V. Smirnov ◽  
Aleksey A. Kechaykin ◽  
Vladislav S. Tenigin ◽  
Ilja A. Shestakov ◽  
Alexander I. Shmakov
Keyword(s):  
Vascular Plants ◽  
New Records ◽  
General Distribution ◽  
The West ◽  
Red Data Book ◽  
New Localities ◽  
Data Book ◽  
The Difference ◽  
Number Of Individuals ◽  
First Time

The article presents new data on the distribution in the territory of Western Altai of 20 species of vascular plants from the families Asteraceae, Betulaceae, Boraginaceae, Crassulaceae, Huperziaceae, Grossulariaceae, Lamiaceae, Onagraceae, Orchidaceae, Papaveraceae, Polygonaceae, Ranunculaceae, Rosaceae, Saxifragaceae и Violaceae. All of them were collected in the highlands of the Korgon Range within the Altai Territory. Of these, Potentilla crebridens is reported for the first time for the Altai Territory and Western Altai; for other species, new localities are indicated. For the first time for the Korgon Range within the Altai Territory, Saxifraga terektensis, Viola tigirekica are presented, and the exact location of Potentilla nivea is noted. New localities of rare and protected species were discovered: Callianthemum sajanense, Huperzia appressa, Pyrethrum alatavicum, Saussurea baicalensis, Scutellaria altaica. For each species, the general distribution, ecology data are given, for some species, notes on the difference and differentiation of them from the closest taxa are indicated. If necessary, the locations of the species previously registered in the Western Altai are indicated. For the species included in the “Red Data Book of the Altai Territory”, we provide an information on the approximate number of individuals in the found populations. Based on the analysis of herbarium material, we exclude Potentilla nervosa from the list of flora of the Altai Territory.

scholarly journals Grosse Fledermausvielfalt in den Waldnaturschutzgebieten des Kantons Zug

2016 ◽  
Vol 167 (5) ◽  
pp. 278-285
Author(s):  
Lucretia Deplazes ◽  
Annie Frey-Ehrenbold ◽  
Martin Ziegler ◽  
Fabio Bontadina
Keyword(s):  
Species Conservation ◽  
Nature Reserves ◽  
Target Species ◽  
Forest Reserves ◽  
Bat Activity ◽  
Alluvial Forests ◽  
Conservation Measures ◽  
National Priority ◽  
Study Sites ◽  
First Time

High bat diversity in forest nature reserves in the Canton Zug Switzerland harbours 30 bat species. Of these, more than 80% have at least part of their habitat in forests. All 22 Swiss priority bat species are considered as forest species. These include twelve forest target species, for which a specific management is required. However, because of the secretive life of bats, missing information on the presence of bat species precluded the implementation of targeted conservation measures. In the last years, new broadband ultrasound recorders were developed as a powerful tool to detect and identify bat species in forests. The aim of our study was to use these new methods to record the presence of bat species in five forest nature reserves in the Canton Zug, to analyse their activity and to evaluate the site-specific differences. During 258 nights of data collection, we recorded 30,522 bat passes of at least twelve different bat species. 23.5% of the recorded bat passes were species from the Swiss Red List. At least three national priority forest target species were detected and three species were discovered for the first time in the Canton Zug. The variation of bat activity between the different forest reserves was high. In particular, areas with diverse and light forest communities, which are rich in dead and decayed wood, proved to be attractive habitats to bats. Alluvial forests, open waters and the presence of old oaks enhanced the diversity of species and bat activity in general. These results were used to define one target species for each forest nature reserve in the study sites and to promote species conservation measures.

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