Parasites in a man-made landscape: contrasting patterns of trematode flow in a fishpond area in Central Europe

Parasitology ◽  
2011 ◽  
Vol 138 (6) ◽  
pp. 789-807 ◽  
Author(s):  
M. SOLDÁNOVÁ ◽  
A. FALTÝNKOVÁ ◽  
T. SCHOLZ ◽  
A. KOSTADINOVA
Keyword(s):  
Agricultural Landscape ◽  
Lymnaea Stagnalis ◽  
Large Body ◽  
Small Scale ◽  
Larval Trematode ◽  
Component Community ◽  
Composition And Structure ◽  
Colonization Potential ◽  
Species Specific ◽  
Transmission Pathways

SUMMARYWe have explored a large body of novel data focusing on small-scale temporal and spatial patterns in the composition and structure of larval trematode communities inLymnaea stagnalis(L.) from a typical Central European agricultural landscape. The 5 eutrophic fishponds studied provide excellent environments for the development of species-rich and abundant trematode communities. Nine prevalent species were consistently present in component communities, but had differential contribution to the parasite flow in the 5 ponds resulting in significant contrasting patterns of community similarity and the prevalence of the 3 major transmission guilds driving this similarity. Component communities split into 2 groups: (i) those from the large pond dominated by anatid and larid generalists with active miracidial transmission; and (ii) those from the smaller ponds dominated by 2 plagiorchioideans infecting snailsviaegg ingestion. We put forward 3 hypotheses for the remarkable differences in larval trematode flow in the similar and closely located eutrophic ponds: (i) species-specific differences in parasite colonization potential displayed by an ‘active-passive’ dichotomy in miracidial transmission strategies of the species; (ii) top-down effects of pond context on transmission pathways of the trematodes; and (iii) competition as an important mechanism in eutrophic environments with a bottom-up effect on component community structure.

scholarly journals The Benefits of Combining Global and Local Data—A Showcase for Valuation and Mapping of Mangrove Climate Regulation and Food Provisioning Services within a Protected Area in Pará, North Brazil

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 432
Author(s):  
Robin Gutting ◽  
Ralf-Uwe Syrbe ◽  
Karsten Grunewald ◽  
Ulf Mehlig ◽  
Véronique Helfer ◽  
...  
Keyword(s):  
Global Climate ◽  
Structural Parameters ◽  
Management Strategies ◽  
Small Scale ◽  
Mangrove Forests ◽  
Food Provisioning ◽  
Local Data ◽  
Climate Regulation ◽  
North Brazil ◽  
Species Specific

Mangrove forests provide a large variety of ecosystem services (ES) to coastal societies. Using a case study focusing on the Ajuruteua peninsula in Northern Brazil and two ES, food provisioning (ES1) and global climate regulation (ES2), this paper proposes a new framework for quantifying and valuing mangrove ES and allow for their small-scale mapping. We modelled and spatialised the two ES from different perspectives, the demand (ES1) and the supply (ES2) side respectively. This was performed by combining worldwide databases related to the global human population (ES1) or mangrove distribution and canopy height (ES2) with locally derived parameters, such as crab catches (ES1) or species-specific allometric equations based on local estimates of tree structural parameters (ES2). Based on this approach, we could estimate that the area delivers the basic nutrition of about 1400 households, which equals 2.7 million USD, and that the mangrove biomass in the area contains 2.1 million Mg C, amounting to 50.9 million USD, if it were paid as certificates. In addition to those figures, we provide high-resolution maps showing which areas are more valuable for the two respective ES, information that could help inform management strategies in the future.

scholarly journals Patterns of fish utilisation in a tropical Indo-Pacific mangrove-coral seascape, New Caledonia

2018 ◽  
Author(s):  
A Dubuc ◽  
N. Waltham ◽  
R. Baker ◽  
C. Marchand ◽  
M. Sheaves
Keyword(s):  
Fish Assemblages ◽  
New Caledonia ◽  
Lunar Cycle ◽  
Forest Edge ◽  
Temporal Variations ◽  
Conservation Strategies ◽  
Small Scale ◽  
Mangrove Forests ◽  
Species Specific ◽  
Main Component

AbstractMangrove forests are important habitats for fish. However, their utilisation by fish, and the specific values they confer, are still not fully understood. This study describes how fish use mangrove forests in an Indo-Pacific mangrove-coral reef seascape. Sampling was conducted using underwater video cameras (UVCs) to describe spatial and temporal variations in fish assemblages across a small-scale (~ 2.5 km2) system, and over the tidal and lunar cycle. UVCs were deployed in the two main component habitats of mangrove forests: at the mangrove forest edge, and inside the forest (5 m from the forest edge), to establish patterns of utilisation of fish across the tidal and lunar cycle. Proximity to coral reefs had a strong influence on the mangrove fish community, as most fish recorded were reef-associated. Juveniles of 12 reef species were observed, including two species classified as vulnerable on the IUCN list, and one endemic species. Fish assemblages on the mangrove edge differed significantly from those inside the forest. Most fish utilised the forest edge, with few species making regular use of in-forest habitats, supporting the contention that most fish species remain on the edge and potentially retreat into the forest for opportunistic feeding, or when threatened by larger predators. Species-specific patterns of utilisation varied across the tidal and lunar cycle. Small differences in depth profiles and substrate across the small-scale system had a significant effect on fish assemblages, highlighting the importance of accounting for spatial heterogeneity in these factors. These data provide important information for managers to implement adequate conservation strategies that include broader interconnected habitat mosaics.

Patterns of abundance and size of Dictyoceratid sponges among neighbouring islands in central Torres Strait, Australia

2007 ◽  
Vol 58 (2) ◽  
pp. 204 ◽  
Author(s):  
Alan R. Duckworth ◽  
Carsten W. Wolff
Keyword(s):  
Spatial Scales ◽  
Distribution Patterns ◽  
Small Scale ◽  
Size Frequency Distribution ◽  
Abundance Patterns ◽  
Size Frequency ◽  
Dysidea Herbacea ◽  
Torres Strait ◽  
Study Sites ◽  
Species Specific

Distribution and size frequency patterns of sessile organisms such as sponges may vary among and within neighbouring reefs. In the present study, we examined small-scale variation of dictyoceratid sponges (class Demospongiae), commonly found on coral reefs, by surveying six neighbouring islands in central Torres Strait. Each island had four study sites, at least 1 km apart, with each site consisting of three shallow (4 to 6 m) and three deep (10 to 15 m) 20 m2 transects. For each transect, we recorded the number of each species and measured the size of the more common dictyoceratid sponges. Seven species of dictyoceratid were recorded in central Torres Strait, with only three species, Coscinoderma sp., Dysidea herbacea and Hyrtios erecta, common to all six islands. Abundance patterns generally varied greatly among islands or sites within islands, perhaps resulting from a combination of physical, biological and stochastic factors. More dictyoceratids were found in deeper water; however, abundance across depth for some species varied among islands or sites. Size-frequency distribution patterns also varied greatly among islands and dictyoceratid species, indicating that factors that may promote growth for one species may not necessarily promote growth for a related species. This study shows that patterns of abundance and size of dictyoceratids can vary greatly over small spatial scales, and that patterns are species-specific.

Managing Spread from Rhizome Fragments is Key to Reducing Invasiveness in Miscanthus × giganteus

2014 ◽  
Vol 7 (3) ◽  
pp. 517-525 ◽  
Author(s):  
Natalie M. West ◽  
David P. Matlaga ◽  
Adam S. Davis
Keyword(s):  
Agricultural Landscape ◽  
Propagule Pressure ◽  
Ecological Integrity ◽  
Low Risk ◽  
Small Scale ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Biofuel Crops ◽  
Combining Data ◽  
Field Edge

AbstractMiscanthus × giganteus, a widely planted biofeedstock, is generally regarded as a relatively low invasion concern. As a seed-infertile species, it lacks a consistent mechanism of long-distance dispersal, a key contributor to invasion rate, and constitutes a low risk for cultivation escape. However, agricultural production shelters plants from stochasticity and increases propagule pressure, enhancing the potential for low-risk species to take advantage of rare dispersal opportunities. Weed risk assessments of M. × giganteus assume the rarity of events such as scouring and flooding that would facilitate secondary dispersal of vegetative rhizome fragments and the long-term sexual inviability of escapes. Combining data from small-scale rhizome fragmentation and movement experiments, and estimates from the literature, we parameterized an individual-based model to examine M. × giganteus spread given three dispersal scenarios. We further evaluated our estimates in response to different field edge buffer widths and monitoring intensities, two key strategies advised for containing biofuel crops. We found that clonal expansion from the field edge alone was sufficient to allow the crop to outgrow buffers of 3 m or less within 11 to 15 yr with low monitoring intensities. Further, models that included the possibility of rhizome dispersal from fields and scouring at field edges demonstrate the potential for long-distance dispersal and establishment with inadequate management. Our study highlights the importance of considering minimum enforced management guidelines for growers to maintain the ecological integrity of the agricultural landscape.

Larval Trematode Assemblages in the Snail Lymnaea stagnalis from Southeastern Wisconsin

1998 ◽  
Vol 84 (2) ◽  
pp. 259 ◽  
Author(s):  
H. Randall Yoder ◽  
James R. Coggins
Keyword(s):  
Lymnaea Stagnalis ◽  
Larval Trematode

Forest development in canopy openings in old-growth Pseudotsuga forests of the western Cascade Range, Oregon

1986 ◽  
Vol 16 (3) ◽  
pp. 558-568 ◽  
Author(s):  
Glenn H. Stewart
Keyword(s):  
Pacific Northwest ◽  
Early Stage ◽  
Cascade Range ◽  
Small Scale ◽  
Spatial Pattern Analysis ◽  
Old Growth ◽  
Tree Population ◽  
Size And Age Structure ◽  
Composition And Structure ◽  
Population Structures

Size and age structure, and spatial pattern analysis were used to study the population dynamics of old-growth Pseudotsugamenziesii (Mirb.) Franco forests of the western Cascade Range, Oregon, U.S.A. Tree population structures confirmed that in the absence of fire, Pseudotsuga was replaced by Tsugaheterophylla (Raf.) Sarg. and (or) Abiesamabilis (Dougl.) Forbes. Regeneration patterns of these species reflected establishment in canopy openings or under Pseudotsuga, but not under Tsuga. Abiesamabilis occurred more frequently as seedlings and saplings in openings than did Tsuga because of favourable aspects of its life history. The composition and structure of the pioneer forest developing after fire was a determinant of subsequent regeneration. If Pseudotsuga dominated, Tsuga and Abies invaded the stand at an early stage. Regeneration in stands where Tsuga was a large component, however, was limited by dense canopies and the occurrence of canopy openings. These patterns demonstrate the importance of small-scale disturbances such as tree falls in the dynamics of Pacific Northwest conifer forests.

Impacts of black stain root disease in recently formed mortality centers in the piñon-juniper woodlands of southwestern Colorado

2005 ◽  
Vol 35 (2) ◽  
pp. 461-471 ◽  
Author(s):  
H SJ Kearns ◽  
W R Jacobi
Keyword(s):  
Plant Cover ◽  
Root Disease ◽  
Pinus Edulis ◽  
Herbaceous Plant ◽  
Tree Seedling ◽  
Frequency Responses ◽  
Ips Confusus ◽  
Composition And Structure ◽  
Species Specific ◽  
Water Holding

Thirty discrete black stain root disease (BSRD) mortality centers, caused by Leptographium wageneri (Kendr.) Wingf. var. wageneri, were examined in 1999 to determine the effects of BSRD on the composition and structure of piñon–juniper woodlands at the tree, shrub, and herbaceous plant levels and on tree-seedling regeneration. In these recently formed mortality centers, the majority (68%) of all piñon (Pinus edulis Engelm.) was dead, 76% of piñon were affected by BSRD, and 70% had evidence of piñon ips bark beetle (Ips confusus Leconte) attack. BSRD mortality centers had a mean area of 0.28 ha (range 0.07 to 0.63 ha). There were no statistically significant (p > 0.05) differences in shrub composition, cover, or diversity between mortality centers and the unaffected surrounding woodlands. Herbaceous plant cover was significantly greater (p < 0.001) within mortality centers and frequency responses were species specific. There were no significant (p = 0.629) differences in the density of piñon regeneration inside mortality centers compared with outside mortality centers. The pathogen was regularly isolated from piñon roots dead for 5–8 years and once from a root dead for 16 years. The rate of radial expansion of mortality centers averaged 1.1 m/year (0.07 SE). The rate of mortality center expansion was not significantly (p > 0.05) related to available water-holding capacity, percent organic matter, pH of soils, piñon density, or any other site data recorded.

RETHINKING THE PURPOSE OF MICRO ENTERPRISES IN DEVELOPING COUNTRIES: EVIDENCE FOR MEXICO

2016 ◽  
Vol 21 (03) ◽  
pp. 1650019
Author(s):  
ALEJANDRO MUNGARAY-LAGARDA ◽  
JOSÉ G. AGUILAR-BARCELÓ ◽  
GERMÁN OSORIO-NOVELA
Keyword(s):  
Large Body ◽  
Profit Maximization ◽  
Operating Conditions ◽  
Small Scale ◽  
Cross Sectional ◽  
Constant Elasticity ◽  
Constant Elasticity Of Substitution ◽  
Financial Survival ◽  
Installed Capacity ◽  
Micro Enterprises

A large body of economic literature has established that the primary purpose of any firm assuming unitary and constant elasticity of substitution of production inputs, among other necessary conditions, is profit maximization. However, the prevailing operating conditions of the micro enterprises raise concerns about the applicability of this formalization. Through an empirical study for Mexico using a four-input translog function (capital, labor, energy and supplies), and based on cross-sectional data, we find that the elasticities of substitution between production inputs are not unitary; in fact, some of them are complementary. This forces us to consider that instead of seeking to maximize profits, some types of micro enterprises are looking to optimize their installed capacity or achieve financial survival of the owner and their family, thus relaxing the foundations of economic analysis for the very small-scale and nascent micro enterprises.

scholarly journals The gut bacterial microbiota of sea turtles differs between geographically distinct populations

2020 ◽  
Vol 42 ◽  
pp. 95-108
Author(s):  
TF Scheelings ◽  
RJ Moore ◽  
TTH Van ◽  
M Klaassen ◽  
RD Reina
Keyword(s):  
Sea Turtles ◽  
Microbial Community Composition ◽  
Sea Turtle ◽  
Microbial Composition ◽  
Bacterial Microbiota ◽  
Composition And Structure ◽  
Loggerhead Turtles ◽  
Breeding Grounds ◽  
The Usa ◽  
Species Specific

The microbiota of metazoans can be influenced by a variety of factors including diet, environment and genetics. In this study we sampled multiple populations from 2 host species that do not overlap in distribution, in order to test whether their bacterial microbiotas are species-specific or more variable. Intestinal swabs were collected from loggerhead turtles originating from Florida, USA, and Queensland, Australia, as well as from flatback turtles from Crab Island, Queensland, and Port Hedland, Western Australia. We then manually extracted bacterial DNA and used 16S rRNA sequencing to explore bacterial microbial community composition and structure. Our investigation showed that the bacterial microbiota of sea turtles is heavily influenced by geography, with loggerhead turtles originating from the USA and Australia harbouring significantly different bacterial microbial populations in terms of composition. Similarly, we also found that flatback turtles from Crab Island had significantly less diverse microbiotas, with a predominance of the bacterial phylum Firmicutes, in comparison to their genetically similar counterparts from Port Hedland. Factors that may explain these observed differences between populations include host genetics, differences in foraging habitat quality and differences in migratory distance (and thus durations of inappetence) between foraging and breeding grounds. The mechanisms by which these factors may influence bacterial microbial composition of sea turtle gastrointestinal tracts warrants further investigation. The results of this study highlight the importance of interpreting microbiota data of wild animals in the context of geography.

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