Methodological tools to study species of the genus Burkholderia

In enclosed water areas, organic matters are actively produced by phytoplankton due to abundant nutrient supply from the rivers. In our study area of the semi-enclosed Hiroshima Bay, oyster farming consuming high primary production has been developed since the 1950s, and the oyster production of Hiroshima prefecture have had the largest market share (ca. 60%) in Japan. In this study, species composition of phytoplankton, primary production, and secondary production of net zooplanktons and oysters were determined seasonally at seven stations in the bay between November 2014 and August 2015. In the bay, diatoms including Skeletonema costatum dominated during the period of the study. The primary productions markedly increased during summer (August), and its mean values in the northern part of the bay (NB) and the southern part (SB) were 530 and 313 mgC/m2/d, respectively. The productions of net zooplankton and oyster increased during the warm season, and its mean values in the NB were 14 and 1.2 mgC/m2/d, and in SB were 28 and 0.9 mgC/m2/d, respectively. The energy transfer efficiencies from the primary producers to the secondary producers in the NB and SB were 2.8% and 9.1%, respectively. However, the transfer efficiency to the oysters was approximately 0.3% in the bay. This study clearly showed the spatial difference of the productions and transfer efficiencies, and the low contribution of the production of oysters in secondary productions in Hiroshima Bay.

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Perspectives on Larval Behaviour in Biophysical Modelling of Larval Dispersal in Marine, Demersal Fishes

Oceans ◽

10.3390/oceans2010001 ◽

2020 ◽

Vol 2 (1) ◽

pp. 1-25

Author(s):

Jeffrey M. Leis

Keyword(s):

Fish Larvae ◽

Behavioural Change ◽

Larval Fishes ◽

Larval Behaviour ◽

Key Issues ◽

Modelling Effort ◽

Validation Research ◽

Vertical Positioning ◽

Study Species ◽

Demersal Fishes

Biophysical dispersal models for marine fish larvae are widely used by marine ecologists and managers of fisheries and marine protected areas to predict movement of larval fishes during their pelagic larval duration (PLD). Over the past 25 years, it has become obvious that behaviour—primarily vertical positioning, horizontal swimming and orientation—of larvae during their PLD can strongly influence dispersal outcomes. Yet, most published models do not include even one of these behaviours, and only a tiny fraction include all three. Furthermore, there is no clarity on how behaviours should be incorporated into models, nor on how to obtain the quantitative, empirical data needed to parameterize models. The PLD is a period of morphological, physiological and behavioural change, which presents challenges for modelling. The present paper aims to encourage the inclusion of larval behaviour in biophysical dispersal models for larvae of marine demersal fishes by providing practical suggestions, advice and insights about obtaining and incorporating behaviour of larval fishes into such models based on experience. Key issues are features of different behavioural metrics, incorporation of ontogenetic, temporal, spatial and among-individual variation, and model validation. Research on behaviour of larvae of study species should be part of any modelling effort.

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Biodiversity of echinoids and their epibionts around the Scotia Arc, Antarctica

Antarctic Science ◽

10.1017/s0954102008001181 ◽

2008 ◽

Vol 20 (3) ◽

pp. 227-244 ◽

Cited By ~ 27

Author(s):

Katrin Linse ◽

Lisa J. Walker ◽

David K.A. Barnes

Keyword(s):

Southern Ocean ◽

Current Knowledge ◽

Sea Urchins ◽

Marine Biodiversity ◽

Current View ◽

Depth Range ◽

Tissue Mass ◽

Scotia Arc ◽

Biodiversity Changes ◽

Study Species

AbstractThe Scotia Arc, linking the Magellan region with the Antarctic Peninsula, comprises young and old islands both near continents and isolated, and is the only semi-continuous link between cool temperate and Antarctic environments. It is an ideal region for studies on how marine biodiversity changes across an extended transition zone. Echinoids (sea urchins) and their associated epibionts were found across depths from 91–1045 m, with 19 species from shelf and four from slope depths. The 23 species from 38 trawls represent 31% of all echinoid species known from the Southern Ocean and 38% of the shelf/upper slope echinoids. The specimens collected comprise representatives of the five families Cidaridae, Echinidae, Temnopleuridae, Schizasteridae and Pourtalesiidae. Echinoids are probably a good model for how well we know Antarctic shelf and slope megabenthos; none of the species we report are new to science but we found nine (39%) of our study species present at new localities, some thousands of kilometres from previous findings. New biogeographic ranges are illustrated forCtenocidaris gigantea,C. nutrix,C. spinosa,Abatus curvidens,A. ingens,A. shackletoni,Amphineustes rostratus,Tripylaster philippiandPourtalesia aurorae. Southern Ocean echinoids show eurybathy as the mean depth range of our study species was 1241 m and only one was at less than 500 m. The current view of echinoid dominance of super-abundance in the shallows seems to be not transferable to shelf and slope depths as only one of 38 trawls was dominated by echinoids. Current knowledge on maximum sizes in Antarctic echinoids seems to be good as our morphometric measurements were mainly within known size ranges. Regular echinoids increased predictably in mass with increasing test length, apart fromCtenocidaris spinosa. Tissue mass of cidaroid species was ~17%, but across irregular species varied from 17.7–8.9%. No epibionts were found on irregular echinoids or Echinidae but 70 cidaroids examined carried 51 species representing ten classes. Many of these species are reported as cidaroid epibionts for the first time. Cidaroids and their epibionts constituted > 38% of the total macrofaunal richness in the trawls they were present in. Echinoids and their epibionts clearly contribute significantly to Southern Ocean biodiversity but are minor components of biomass except in the shallows.

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Effects of Natural Variation in Sex Ratio and Habitat Structure On Mate-Guarding Decisions in Amphipods (Crustacea)

Behaviour ◽

10.1163/156853996x00567 ◽

1996 ◽

Vol 133 (13-14) ◽

pp. 985-996 ◽

Cited By ~ 49

Author(s):

Jaimie T.A. Dick ◽

Robert W. Elwood

Keyword(s):

Natural Populations ◽

Mate Guarding ◽

Reproductive Behaviour ◽

Male Competition ◽

Female Body Size ◽

The Social ◽

Size Assortment ◽

Assortative Pairing ◽

Study Species

AbstractWe employed field-based studies, with complementary laboratory-based studies, to investigate social and environmental influences on tactical mate-guarding decisions in amphipods (Crustacea). Firstly, we investigated variation in precopulatory mate-guarding duration in Cammarus duebeni celticus in relation to the social structure of natural populations. Variation in population density of up to two orders of magnitude had no effect on precopula duration, whereas guarding durations increased as the sex ratios of the populations became more male biased. That is, males have some ability to assess the probability of other males taking females into precopula and are prepared to guard for longer as this threat of male: male competition increases. A field demonstration of tactical shifts in reproductive behaviour in response to pertinent social conditions is thus provided. Secondly, the 'habitat segregation' hypothesis, which proposes that positive size-assortative pairing in amphipod populations arises due to variation in the use of micro-habitats, was tested in natural field populations and under laboratory conditions in Echinogammarus marinus. This was necessary in order to distinguish any purely environmental determinants of size-assortment from the role of active decisions by males concerning mate choice and male: male competition. The hypothesis was rejected on the grounds that size-assortative pairing arises under both heterogeneous and homogeneous environmental conditions. Further, in both study species, male and female body size were positively correlated with precopula duration. Thus, indirect competition for access to large, fecund females, based on the timing of male entry into precopula, together with direct aggression, provides the explanation for size-assortative pairing in amphipods.

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Letter to editor: Incorrect identification of study species

Comparative Clinical Pathology ◽

10.1007/s00580-016-2371-5 ◽

2016 ◽

Vol 26 (1) ◽

pp. 9-10

Author(s):

Mahmood Soofi ◽

Arash Ghoddousi ◽

Lukas Egli ◽

Igor Khorozyan ◽

Matthias Waltert

Keyword(s):

Study Species

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Association of three succulent plant species with woody canopy in the mixed bushveld, South Africa

Koedoe ◽

10.4102/koedoe.v41i2.254 ◽

1998 ◽

Vol 41 (2) ◽

Cited By ~ 3

Author(s):

I. Thrash

Keyword(s):

South Africa ◽

Plant Species ◽

Arid Areas ◽

Nurse Plant ◽

Succulent Plant ◽

Two Phases ◽

Possible Cause ◽

Study Species

Succulents are an important component of the mixed bushveld. Although the nurse plant syndrome is known from arid areas, association of succulents with woody canopy has ot been studied in non-arid areas. The study was done in two phases, the first being to confirm the existence of an association and the second being to investigate a possible cause of the association. The three species studied were all significantly associated with woody canopy. All of the relatively small (0-1 m) Euphorbia ingens plants and most of the relatively small (0-0.5m) Aloe marlothii and Opuntia vulgaris plants encountered were beneath woody canopy. There was a very strong significant association between being damaged by fire and growing between woody canopies for all three species. Fires are likely to be lethal to any plants of the study species that are shorter than about 1 m. In any area where fires are frequent there are likely to be fewer young plants of the study species between woody canopies than there will be within the protection of a bush clump.

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PHYTOSOCIOLOGICAL ANALYSIS OF THE MEDICINAL PLANT SPECIES, THALICTRUM JAVANICUM BLUME IN THOTTABETTA, NILGIRIS, THE WESTERN GHATS

Kongunadu Research Journal ◽

10.26524/krj68 ◽

2015 ◽

Vol 2 (1) ◽

pp. 56-62

Author(s):

Abinaya G ◽

Paulsamy S

Keyword(s):

Western Ghats ◽

Tamil Nadu ◽

Degree Of Dominance ◽

The Family ◽

Qualitative Characters ◽

The Nilgiris ◽

The Western Ghats ◽

Study Species ◽

Phytosociological Study

Phytosociological study is the most essential in any community to know its structure and organization. The various qualitative characters obtained are used to determine the level of distribution, numerical strength and degree of dominance exhibited by the constituent species in the community. Thalictrum javanicum belongs to the family Ranunculaceae family, it is medium sized erect herb, found in the temperate Himalayas from Kasmir to Sikkim in Khasi hills, and Kodaikanal and Nilgiri hills of Western Ghats in Tamil Nadu, India. At global level, it is generally distributed in the hilly tracts of India, Srilanka, China and Java at the altitude of around 2400 m above msl. The present study was undertaken in Thottabetta , the Nilgiris by sampling using belt transects of 10x1000m size which further divided into 100 segments each which 10x10m size. The total number of species encountered in the study area is 45 which includes 5 grasses and 40 forbs. The quantitative ecological characters of the study species, T. javanicum is a detailed below: frequency 11%, abundance 3.82 individuals/m2, density 0.42 individuals/m2, basal cover 172.20/mm2/ m2, relative frequency 0.55% and relative density 0.08%, relative dominance 0.16%. Based on the ecological attributes it is determined that the species, T. javanicum is less perpetuated in the community studied. Hence, further studies on the determination of propagation strategies for population enhancement and conservationof wilds are suggested.

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Ichthyofauna sampled with tadpoles in northeastern Maranhão state, Brazil

Check List ◽

10.15560/11.1.1550 ◽

2015 ◽

Vol 11 (1) ◽

pp. 1550 ◽

Cited By ~ 5

Author(s):

Rodrigo Matavelli ◽

Aldenise Martins Campos ◽

João do Vale ◽

Nivaldo Magalhães Piorski ◽

Paulo Dos Santos Pompeu

Keyword(s):

Species Richness ◽

Atlantic Forest ◽

River Basins ◽

Fish Diversity ◽

Estuarine Ecosystems ◽

Lotic Habitats ◽

Freshwater Habitats ◽

High Fish ◽

Study Species

The Neotropic region has high fish diversity associated with freshwater habitats. However, for Maranhão state, most publications on the ichthyofauna concentrate on coastal or estuarine ecosystems. In this study, species of fish were sampled in lentic and lotic habitats in Cerrado areas (Cerradão phytophysiognomy) and in restinga areas (Atlantic Forest phytophysiognomy) in northeastern Maranhão state between January and July 2010. Thirteen species from 10 families and 6 orders were captured. Species richness was highest for the orders Characiformes and Gymnotiformes. Our results are the first records of the ichthyofauna of coastal drainage areas of northeastern Maranhão state, contributing to the understanding of the biodiversity of the Munim and Parnaíba River basins, and suggest the existence of a community that shares elements with those of the Amazon and Caatinga biomes.

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Trematode Parthenitae Infection Rate and Distribution of Kola Bay Actic Molluscs of the Genus Littorina

KnE Life Sciences ◽

10.18502/kls.v5i1.6027 ◽

2020 ◽

Author(s):

Kseniia Kulesh ◽

Petr Kravets ◽

Ivan Bacherikov

Keyword(s):

Infection Rate ◽

Littoral Zone ◽

Age Distribution ◽

Age Groups ◽

Metal Structure ◽

Distribution Data ◽

Free Living ◽

Autumn Period ◽

Metal Construction ◽

Study Species

The study was carried out in 2018 in the littoral zone of Kola Bay during the autumn period in the areas of Abram Mys Settlement, Mishukovo Settlement and Retinskaya Bay. Molluscs of the genus Littorina were collected from various substrates: stones, algae, metal construction and soil. In addition, samples were taken not from a particular substrate, but along the borders of the littoral zone to study species composition of molluscs and common level of infection rate in study areas. Our data showed that L. saxatilis infested by mature trematode parthenitae prefer being on the surface of algae, metal structure, stones at low tide instead of hiding under the stones, in the thickness of algae and in other possible shelters. The study of age distribution among infested Littorina molluscs living on different substrates showed that the ratio of age groups is different and varies from 1+ to 13+. Distribution data are established and considered for infested molluscs by trematode parthenitae of the group ”pygmaeus”: Microphallus pygmaeus, M. piriformes, which are characterized by the absence of free-living cercariae. Trematode parthenitae of other species which have a stage of free-living cercaria in their life cycle are absent in molluscs during the autumn period.

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