Search results for "Common species"
showing 10 items of 29 documents
Reduced prevalence of soil-transmitted helminths and high frequency of protozoan infections in the surrounding urban area of Curitiba, Paraná, Brazil
2019
Human populations living in the surrounding urban areas of large Brazilian cities have increased vulnerability to intestinal parasites. However, the epidemiological scenario of soil-transmitted helminths (STH) in Curitiba, Paraná's main city, remains largely unknown. To bridge this gap of knowledge, this study aims to determine the prevalence of intestinal parasites and to investigate potential transmission pathways of the most prevalent species detected. We conducted a cross-sectional epidemiological study between July and September 2014 among schoolchildren in urban and peri-urban (deprived) areas of the municipality of Campo do Tenente, Curitiba. A total of 549 stool samples were used fo…
Presence of the genus Cuon in upper Pleistocene and initial Holocene sites of the Iberian Peninsula: new remains identified in archaeological context…
2010
The dhole (Cuon alpinus) has been documented on the Iberian Peninsula throughout the Middle and Upper Pleistocene in archaeological and palaeontological contexts. However, this is an uncommon species among the Iberian quaternary faunae as a whole. This paper focuses on the remains of the genus Cuon recovered in three different sites of the Iberian Mediterranean region and their morphological and osteometrical study. By comparing these with fourteen complete skeletons of Canis lupus, as well as with other remains of C. alpinus, we intend to highlight some anatomical and metrical differences between Cuon and Canis that, added to those already published, could be a functional base-line for the…
Plant litter decomposition and microbial characteristics in volcanic soils (Mt Etna, Sicily) at different stages of development
2006
Soils at different developmental stages were sampled from eight sites on the slopes of Mt Etna, Sicily (Italy) and characterized for total C, microbial biomass and microbial respiration. The values of these parameters were greatest for the most developed soils, but differences in recent management and site characteristics limited analysis of trends with soil development across the eight sites. The decomposition kinetics of both intact leaf litter and the water-insoluble fraction of leaf litter from three common species on Etna [Etnean broom (Genista aetnensis), European chestnut (Castanea sativa), and Corsican pine (Pinus nigra)] were determined in four of the soils (the two with the smalle…
Reconstruction of the former charophyte community out of the fructifications identified in Albufera de València lagoon sediments
2010
Abstract Several decades ago, due to eutrophication, Albufera de Valencia lagoon lost the charophyte meadows that covered the bottom in the past but had never been studied in detail. An area close to the lagoon will be restored now to improve water quality and to recover submerged vegetation. To have information on the background of the charophytes from this area, four 80–87 cm long sediment cores were extracted from the lagoon. The subfossil charophyte fructifications (oospores and gyrogonites) were isolated and identified in two of the four cores. Moreover, sediment core fractions from the third and fourth cores were allowed to germinate under several conditions. The study of the lagoon s…
Selection in captive populations
1986
We have briefly reviewed types of genetic variation and selection in the wild as contrasted with selection in captive populations, along with the objectives of captive breeding programs, before recommending selection procedures for the genetic management of captive populations. Although some inadvertent selection for tameness and adaptation to captive environments is inevitable in captive populations, any selection that is actively applied to captive populations should have clearly defined objectives. Much of the apparent disagreement about genetic management of captive populations probably stems from the varying objectives of different captive breeding programs. Objectives differ depending…
We need to appreciate common synanthropic plants before they become rare: Case study in Latgale (Latvia)
2020
Local ecological knowledge holds great potential in contributing to sustainable resource management and conservation activities. For this reason, the authors choose to analyse an ethnobotanical dataset from the Baltic Sea region by exploring the relationship between plants and humans on the basis of three main categories: habitat characteristics, distribution in the wild and plant sensitivity to human impact beyond physical distance. The study provides empirical evidence of widespread usage of so-called common species which are widely distributed in the territory and benefit from human activity. When considering the data via the intensity of use, based on detailed use-reports (DUR), the mai…
Local Extinction of Dragonfly and Damselfly Populations in Low- and High-Quality Habitat Patches
2010
Understanding the risk of extinction of a single population is an important problem in both theoretical and applied ecology. Local extinction risk depends on several factors, including population size, demographic or environmental stochasticity, natural catastrophe, or the loss of genetic diversity. The probability of local extinction may also be higher in low-quality sink habitats than in high-quality source habitats. We tested this hypothesis by comparing local extinction rates of 15 species of Odonata (dragonflies and damselflies) between 1930-1975 and 1995-2003 in central Finland. Local extinction rates were higher in low-quality than in high-quality habitats. Nevertheless, for the thre…
Experimental study on the influence of paper and pulp mill effluent on the gill parasite communities of roach (Rutilus rutilus)
1996
SUMMARYRoach (n= 81) caught on 23 May, 1992 from oligotrophic, unpolluted Lake Peurunka were kept in cages over a 2-week period before moving half of the fish to nearby Lake Vatia, which is influenced by pulp mill effluents. Before moving the fish gill parasites were examined from 9 fish; 5Dactylogyrusspecies,Gyrodactylussp. andParadiplozoon homoionwere found, the main components of the infracommunities being dactylogyrids. Afterwards, 5 fish from each lake were studied weekly between 1 July and 17 August. Metazoan parasites were recorded from gill arches divided into 4 sections along the dorso-ventral axis.D. crucifer, D. nanus, D. micracanthusandD. suecicusoccurred in both lakes throughou…
Early oysters and their supposed Permian ancestors
2005
The origin of oysters is a much debated palaeontological issue. Recent morphological studies indicate that oysters are characterized by a particular ribbing pattern, the so-called antimarginal ribs which are characterized by a proper morphogenetic pattern. Therefore antimarginal ribs can be used as a diagnostic character in phylogeny. The earliest recognized bivalve displaying diagnostic features of oysters (sinistral attachment to the substrate, typical hinge and ligament structure, and antimarginal ribs) is Ostracites cristadifformis Schlotheim, 1820 first appearing in the Anisian of Europe. This common species was later attributed to Enantiostreon and is here transferred to Umbrostrea. S…
Scaled chrysophytes (Chrysophyceae and Synurophyceae) from national park lakes in southern and central Finland
1989
A total of 34 scaled chrysophyte taxa (18 Mallomonas spp., 6 Synura spp., 2 Chrysosphaerella spp., 6 Spiniferomonas spp. and 2 Paraphysomonas spp.) were recorded by SEM techniques in 61 samples from 59 lakes locating in 8 national parks of southern and central Finland in July 1987. Most of the lakes were small forest and peat bog lakes with acid (pH 4.6–7.2) and soft-water and with variable water colour (10–350 mg Pt/l). The number of taxa per lake varied from 0 to 15 and it correlated very significantly with the water pH. The species structure was rather typical for the oligotrophic and acid lakes. Besides the eurytypic and common species like Mallomonus caudata (fr. 72.1% of lakes), M. cr…