Preferensi Habitat Ikan Gabus [Channa striata (Bloch 1793)] di Perairan Rawa Aopa, Sulawesi Tenggara

The use of habitat by fish is closely related to efforts to find the best conditions for the survival of these fish. This study aims to analyze the habitat preferences of Striped snakehead in Rawa Aopa waters, Southeast Sulawesi. This research was conducted from November 2018 to February 2019 in the waters of Swamp Aopa Southeast Sulawesi. Fish collection using traps. The constancy and fidelity index determined the preference of striped snakehead for habitat type. A total of 1024 striped snakehead fish were caught during the study with a length range of 200,0-420,0 mm and 69,0-596,0 g weight. Striped snakehead measuring 200-367 mm were consistent in occupying habitats with a slightly dense to dense water plant density, while sizes 368-388 and 389-430 mm were consistent in habitats with sparse water plant density. The preference level of striped snakehead fish size 389-430 mm to habitats with rare aquatic plants is very high (Fij = 6). Therefore, the size can be used as an indicator of habitats with the rare aquatic plant category. The preference for 200-367 mm striped snakehead fish in dense aquatic plant habitats indicates that these habitats are foraging, growing, and protective zones. Keywords: Channa striata, fish habitat, Rawa Aopa, Southeast Sulawesi, stripe snakehead

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Distribution and habitat preference of protected reindeer lichen species (Cladonia arbuscula, C. mitis and C. rangiferina) in the Balaton Uplands (Hungary)

The Lichenologist ◽

10.1017/s0024282921000165 ◽

2021 ◽

Vol 53 (3) ◽

pp. 271-282

Author(s):

Mónika Sinigla ◽

Erzsébet Szurdoki ◽

László Lőkös ◽

Dénes Bartha ◽

István Galambos ◽

...

Keyword(s):

Vascular Plants ◽

Management Practices ◽

Soil Depth ◽

Habitat Preferences ◽

Habitat Type ◽

Canopy Cover ◽

Lichen Species ◽

Oak Forests ◽

Natural Habitats ◽

Cladonia Rangiferina

AbstractThe maintenance of protected lichen species and their biodiversity in general depends on good management practices based on their distribution and habitat preferences. To date, 10 of the 17 protected lichen species of Hungary have been recorded in the Bakony Mts including the Balaton Uplands region. Habitat preferences of three protected Cladonia species (C. arbuscula, C. mitis and C. rangiferina) growing on underlying rocks of red sandstone, basalt, Pannonian sandstone and gravel were investigated by detailed sampling. We recorded aspect, underlying rock type, soil depth, pH and CaCO3 content, habitat type (as defined by the General National Habitat Classification System Á-NÉR), all species of lichen, bryophyte and vascular plants as well as percentage cover of exposed rock, total bryophytes, lichens, vascular plants and canopy, degree of disturbance and animal impacts. Sporadic populations of these species mostly exist at the top of hills and mountains in open acidofrequent oak forests, but they may occur in other habitats, such as closed acidofrequent oak forests, slope steppes on stony soils, siliceous open rocky grasslands, open sand steppes, wet and mesic pioneer scrub and dry Calluna heaths. Cladonia rangiferina was found to grow beneath higher canopy cover than either C. arbuscula or C. mitis in the Balaton Uplands. Furthermore, there were significant differences in canopy cover between occupied and unoccupied quadrats in the case of all three species. Cladonia rangiferina is a good indicator species of natural habitats in Hungary due to its restricted distribution and low ecological tolerance. These results may lead to the adoption of effective conservation methods (e.g. game exclusion, artificial dispersal) in the future.

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Physical Characteristics of Gelatin from Cork Fish skin in The Waters of Merauke

E3S Web of Conferences ◽

10.1051/e3sconf/202014703027 ◽

2020 ◽

Vol 147 ◽

pp. 03027

Author(s):

Diah Lestari Ayudiarti ◽

Ema Hastarini ◽

Rini Susilowati

Keyword(s):

Acetic Acid ◽

Gel Strength ◽

Physical Characteristics ◽

High Protein ◽

Fish Skin ◽

Fish Meat ◽

Channa Striata ◽

Very High

Cork fish (Channa striata) is a swamp fish that population very abundant in Merauke. This fish meat is rich in albumin and is usually used as an additional supplement for people who have undergone surgery. Cork fish skin also contains very high protein, which one of them is gelatin. Research on physical characteristics of gelatin from cork fish skin in the waters of merauke has been done. Gelatin were made by soaked the cork fish skin into acetic acid 0.5 M at concentration 2, 4 and 6% for12 hours. After soaked, the skins were washed by water until neutralized (pH 6), then it were extracted using aquadest (1:3) at 70oC for 2 hours. The filtrates then were filtered and dried in oven at temperature 40-50oC. The result showed that the best gelatin extraction was using acetic acid 0.5 M in concentration 6% with yield 10.15%, gel strength 169.45 gbloom, viscosity 14.31 cPs, white degree 52.

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Management implications of juvenile reef fish habitat preferences and coral susceptibility to stressors

Marine and Freshwater Research ◽

10.1071/mf09141 ◽

2010 ◽

Vol 61 (5) ◽

pp. 532 ◽

Cited By ~ 16

Author(s):

Edward E. DeMartini ◽

Todd W. Anderson ◽

Jean C. Kenyon ◽

James P. Beets ◽

Alan M. Friedlander

Keyword(s):

Coral Bleaching ◽

Fish Habitat ◽

Habitat Preferences ◽

Reef Fishes ◽

Relative Susceptibility ◽

Rugose Corals ◽

Fish Juveniles ◽

Juvenile Reef Fish ◽

Juvenile Stages ◽

Ecological Importance

In the Hawaiian Archipelago, shelter-dependent juvenile stages of many reef fishes and their coral habitats are increasingly put at risk by multiple anthropogenic stressors (e.g. overfishing and habitat loss, coral bleaching and sedimentation, respectively). We assessed coral bleaching (to identify relative susceptibility among growth forms) and the use v. availability of structurally complex and simple corals by juvenile reef fishes in Hawai'i. We use these data in a model that identifies habitats and resource species for managing reef fisheries and conserving coral habitats. Many juvenile reef fishes preferentially inhabit rugose corals. The economic and ecological importance of these fishes varies from those with little value to others, such as highly prized parrotfishes that also serve as ecological engineers. Coral species also differ in their relative susceptibility to anthropogenic and natural stressors – more structurally complex corals tend to be more susceptible to stressors. Our model relates the economic and ecological valuations of fish resources with specific preferences of fish juveniles for corals of varying susceptibility, testing the prediction that risk should co-vary among species of corals and fishes. Managers should use such a model when prioritising habitats and resource species for conservation.

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Effects of high plant populations on the growth and yield of winter oilseed rape (Brassica napus)

The Journal of Agricultural Science ◽

10.1017/s0021859698006091 ◽

1999 ◽

Vol 132 (2) ◽

pp. 173-180 ◽

Cited By ~ 47

Author(s):

J. E. LEACH ◽

H. J. STEVENSON ◽

A. J. RAINBOW ◽

L. A. MULLEN

Keyword(s):

Brassica Napus ◽

Oilseed Rape ◽

Plant Density ◽

High Density ◽

Growth And Yield ◽

Winter Oilseed Rape ◽

Plant Populations ◽

Rothamsted Experimental Station ◽

Plant Densities ◽

Very High

The effects of plant density on the growth and yield of winter oilseed rape (Brassica napus) were examined in a series of five multifactorial experiments at Rothamsted Experimental Station between 1984 and 1989. Plant densities, manipulated by changing the seed rate and row spacing, or because of overwinter losses, ranged from 13·5 to 372 plants/m2. Normalized yields for the multifactorial plots increased with densities up to 50–60 plants/m2. In very high density plots in 1987/88, yield decreased as density increased >150 plants/m2. Plants grown at high density had fewer pod-bearing branches per plant but produced more branches/m2. Branch dry matter (DM) per plant was decreased by 42%, the number of fertile pods per plant and pod DM/plant by 37%. There was no effect of density on the number or DM of pods/m2. Over 74% of the fertile pods were carried on the terminal and uppermost branches of plants grown at high density in 1987/88 compared with only 34% in plants grown at low density in 1988/89. Seed DM/plant decreased with increase in density but seed size (1000-seed weight) increased. There was no effect of density on seed glucosinolate or oil contents.

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Analysis for Underwater Sound on Natural River Habitat

E3S Web of Conferences ◽

10.1051/e3sconf/20184002047 ◽

2018 ◽

Vol 40 ◽

pp. 02047

Author(s):

Jung-Eun Gu ◽

Sang Hwa Jung ◽

Joongu Kang ◽

Hyoseop Woo

Keyword(s):

Underwater Acoustics ◽

Fish Habitat ◽

Habitat Type ◽

High Water ◽

Physical Structure ◽

Physical Habitat ◽

Hydraulic Characteristics ◽

Underwater Sound ◽

Underwater Acoustic ◽

Sound Environment

A riffle-pool structure is a representative physical structure of bed in rivers. The change in the physical parameter of the habitat could lead to changes in the sound environment of rivers, which are expressed by underwater acoustics. This change in underwater sound affects fish habitat. In this study, the changes of underwater acoustics were analyzed according to the change of pool-riffle sequence in a natural river. And the correlation between underwater acoustics and hydraulic characteristics was investigated. The survey for underwater acoustics was performed in the Namdae stream where is in Gangwon province. This stream belongs to the Han River basin and the river length is 39.01 km and the catchment area is 127.56 km2. The Namdae stream is a river that accounts for more than 70% of salmon returning to South Korea. The spawning salmon will return to this area around November after growing in the Bering Sea. It is important to manage the fish habitat in this river so there is a lot of research on the enhancement of fish habitat. Hydraulic characteristics were changed by the river bed structure. In this study, we investigated the relationship between underwater acoustic characteristics and hydraulic factors such as riverbed material, flow rate and water depth of each habitat type at 12 sites. The characteristics of underwater acoustic differed relative to different hydraulic factors of the two habitats, which is riffle and pool. The sound pressure level of riffles was relatively higher than that of the pools due to bed materials, shallow depth and high water velocity of riffles. In the future, it is considered that the underwater sound can be utilized as a parameter to evaluate the physical habitat environment of the river.

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Corrigendum to: Distribution and relative abundance of forest duikers in Dassioko Sud Forest Reserve (coastal Côte d'Ivoire)

Wildlife Research ◽

10.1071/wr17068_co ◽

2018 ◽

Vol 45 (2) ◽

pp. 194

Author(s):

K. A. Yao ◽

E. A. Bitty ◽

K. B. Kassé ◽

Y. C. Kouakou ◽

K. H. Yaokokoré-Beibro ◽

...

Keyword(s):

Relative Abundance ◽

Habitat Preferences ◽

Habitat Type ◽

Distribution Patterns ◽

Encounter Rate ◽

Line Transect ◽

Habitat Types ◽

Anthropogenic Pressures ◽

Forest Reserve ◽

Encounter Rates

Context Duikers play a vital role in maintaining forest ecosystems, as both seed dispersers and prey. In West Africa, duikers are also an important source of food and income; however, it is likely that some species are now being hunted at unsustainable levels. So as to contribute to duiker conservation, we used line-transect data and additional information on dung and track counts to estimate relative abundance and establish distribution patterns of forest duikers in Côte d'Ivoire's Dassioko Sud Forest Reserve (DSFR), a poorly known, remnant coastal rainforest. We also collected basic information on hunting pressure. Methods Forest duiker counts were made twice per month from July 2013 to March 2014 on six line transects of varying lengths (5.6–6.7km) and in different regions of the DSFR, representing different habitat types. The number of sightings per kilometre walked, defined as ‘encounter rate', was used to compute an index of relative abundance. We recorded all evidence of poachers and used these data to generate a poaching index (# poaching signs per kilometre) for different habitat types. Key results The DSFR has lost three of seven total forest duiker species and populations of the four remaining species are declining. Encounter rates were greatest for Philantomba maxwellii (0.46 indices km–1) and accounted for 68% of total encounters. Cephalophus niger, C. dorsalis and C. silvicultor were encountered at similar (0.07 indices km–1) but much lower rates. For all species, mean encounter rates were highest in degraded forest (0.38–0.73 indices km–1), followed by secondary (0.2–0.44 indices km–1) and primary (0.19–0.44 indices km–1) forest. Conclusions Of the four forest duiker species still present in the DSFR, the black, bay and yellow-backed duikers are the most affected by anthropogenic pressures. Duiker abundance in the DSFR varies with habitat type. This variation is apparently influenced by differences in forest structure, poaching pressure and proximity to villages. Implications The study provides baseline data for future managing of ungulate populations in the DSFR. We recommend that a biomonitoring study of duiker populations be initiated immediately to help determine population trends, investigate habitat preferences, and help curb illegal hunting activities in this important forest reserve.

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A Comparison of (100) Hg1−x Cdx Te and Hg1−x ZnxTe Grown By Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-102-85 ◽

1987 ◽

Vol 102 ◽

Author(s):

R. D. Feldman ◽

R. F. Austin ◽

P. M. Bridenbaugh

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Near Infrared ◽

Wave Length ◽

High Electron ◽

Mbe Growth ◽

Suitable Material ◽

Zn Content ◽

Length Range ◽

Very High

ABSTRACTFilms of HgCdTe with x < 0.6 and of HgZnTe with x < 0.26 have been grown by molecular beam epitaxy (MBE). Very high electron mobilities have been achieved for both materials in the small bandgap region. Hall mobilities at 77K reach 4.8 × 105 cm2 /V-s for Hg0 87 Zn0.13 Te, and 3.1 × 105 cm2/V-s for Hg0.87 Zn0.13 Te. HgCdTe growth was easily extended to the 1.5 – 3 μm wave length range. Attempts to extend HgZnTe to these bandgaps were unsuccessful due to defects that are induced by surface roughness in high Zn-content films. These results suggest that HgCdTe is the more suitable material for MBE growth for near infrared applications.

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Status, habitat and conservation of the Rufous-fronted Antthrush Formicarius rufifrons

Bird Conservation International ◽

10.1017/s0959270900001118 ◽

1995 ◽

Vol 5 (2-3) ◽

pp. 391-404 ◽

Cited By ~ 7

Author(s):

Andrew W. Kratter

Keyword(s):

Habitat Preferences ◽

Habitat Type ◽

Dense Layer ◽

Madre De Dios ◽

Second Growth ◽

Satellite Photograph ◽

Lowland Forests ◽

Two Measures ◽

Del Rio ◽

Global Population

SummaryHabitat preferences of the Rufous-fronted Antthrush Formicarius rufifrons were studied along the Rio Tambopata in south-eastern Peru. All territories of this threatened species, endemic to lowland forests in the department of Madre de Dios, Peru, contained the near-juxtaposition of two distinct vegetation types: tall floodplain forest with shaded understorey, and more open, second-growth vegetation with a very dense layer of vegetation close to the ground. The latter habitat type was closely associated with disturbances, such as river erosion, tree falls, or human clearings. Two measures of antthrush density were calculated for the study area. A satellite photograph was used to identify appropriate habitat along the upper Rio Tambopata, and using the antthrush density figures, a population size of 100-500 pairs was estimated for this area. This estimate was then used to calculate a global population of 700-3,500 pairs. Approximately 207c of the global population occurs within currently protected areas. The habitat and diet of this species are discussed in relation to two othercongeners.Las preferencias de hábitat de Formicarius rufifrons fueron estudiadas a lo largo del Tambopata en el sureste del Perú. Los territorios de esta amenazada especie, endémica de los bosques tropicales en el depto. de Madre de Dios, están compuestos por dos formaciones vegetales distintas: bosque alto de llanura y vegetación secundaria con un estrato inferior tupido. La vegetación secundaria se debe a los trastornos ecológicos, tales como la erosión fluvial, las caidas de árboles, y también a la tala de bosques. Los limites inferior y superior de densidad (tasa de población) fueron calculados en el área de estudio; los habitats apropriados se identificaron a lo largo del rio a través de imágenes de satélite y se pudo calcular un total de 100-500 parejas para la zona. Se empleó la tasa poblacional, entonces, para calcular la supuesta población global de 700-3,500 parejas. Hoy en dia, aproximadamente 20% de la población global de la especie ocurre dentro de áreas protegidas. Se trata, ademas, el hábitat y la dieta de F. rufifrons en relatión a dos especies congenéricas.

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Habitat preferences in freshwater diatom communities from sub-Antarctic Îles Kerguelen

Antarctic Science ◽

10.1017/s0954102001000050 ◽

2001 ◽

Vol 13 (1) ◽

pp. 28-36 ◽

Cited By ~ 23

Author(s):

Bart Van De Vijver ◽

Pieter Ledeganck ◽

Louis Beyens

Keyword(s):

Habitat Preferences ◽

Habitat Type ◽

Research Station ◽

Running Waters ◽

Diatom Flora ◽

Limited Sampling ◽

Sampling Campaign ◽

Diatom Communities ◽

Geographical Position ◽

Freshwater Diatom

A limited sampling campaign on the main island of Îles Kerguelen revealed 170 freshwater diatom taxa, belonging to 29 genera. Four different communities were distinguished in two major groups, being determined principally by habitat type. The Fragilaria vaucheriae–Fragilaria germainii assemblage occurs exclusively in running waters. The three other communities, observed in standing waterbodies, are separated by their geographical position on the island with the Fragilaria exigua–Aulacoseira alpigena and the Fragilaria exigua–Fragilaria vaucheriae assemblages, mainly found in the Lac Studer area and the Fragilaria pinnata var. pinnata assemblage, recorded near the coastal line and the research station. Analysis of different waterbody types revealed the habitat preference of the various diatom taxa and identified a diatom flora for running waters and one preferring stagnant waterbodies.

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Spatiotemporal variation in the adult sex ratio, male aggregation, and movement of two tropical cloud forest dung beetles

Current Zoology ◽

10.1093/cz/zoab101 ◽

2021 ◽

Author(s):

Julliana Barretto ◽

Martha L Baena ◽

Israel Huesca Domínguez ◽

Federico Escobar

Keyword(s):

Life History ◽

Sex Ratio ◽

Life History Traits ◽

Cloud Forest ◽

Habitat Preferences ◽

Habitat Type ◽

Dung Beetle ◽

Adult Sex Ratio ◽

The Face ◽

Male Aggregation

Abstract While theory suggests that at conception the sex ratio should be balanced (1:1), this can be variable across space and time in wild populations. Currently, studies of the environmental factors that regulate adult sex ratio (ASR) in species with different life-history traits are scarce. Using capture-recapture over a year, we analyzed the influence of habitat type (forest and non-forest) and season (rainy and dry) on variation in ASR, male aggregation and the trajectory movement of two dung beetle species with different life-history traits: Deltochilum mexicanum (a hornless roller species) and Dichotomius satanas (a tunneler species with horns on its head and thorax). We found opposite tendencies. The D. mexicanum population tends to be female-biased, but the population of D. satanas tends to be predominantly male, and observed values were not related to habitat type or season. However, the 95% confidence intervals estimated were highly variable between seasons depending on habitat. On examining the monthly variation in ASR for both habitats, we found that it depends on the species. In addition, male aggregation differed between species depending on habitat type and season, and species movement patterns were closely related to their habitat preferences. Based on our results, we argue that comparative population studies of species with different life-history traits are necessary to understand the variation in demographic parameters as well as its ecological and evolutionary implications in the face of spatial and climatic environmental variation.

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