Isotopic niche and niche overlap in benthic crustacean and demersal fish associated to the bottom trawl fishing in south-central Chile

Demak is a coastal area on the North Coast of Java with a large enough potential for demersal fish resources. This research aimed to determine the composition, the length and weight distribution, and catch per unit effort (CPUE) of demersal fish caught using mini bottom trawl at the north coast of Demak Regency. The research was carried out in October-December 2020 by observation of ten trips of mini bottom trawl fishing. Each fish captured was then grouped by type, identified, and measured its length and weight. The result showed that 38 species consist of 31 fishes, four mollusks, and three crustaceans. The fish captured dominated by pony fish (Leiognathus equulus) as much as 31.23% and largehead hairtail (Trichiurus lepturus) of 23.52%. The catch per unit effort (CPUE) average of mini bottom trawl was 44.77 kg/trip. Mainly fish (more than 95%) caught in small size compared it’s the maximum attainable length (L-max), with all the weight ranges from 0.3 to 520 g and more than 98% sized 0.3-80 g. Mini bottom trawl catches many types of fish and small size; therefore, mini bottom trawl is classified as a type of fishing gear with a very low selectivity level.

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Spatio-temporal trends in diversity of demersal fish assemblages in the Mediterranean

Scientia Marina ◽

10.3989/scimar.04977.13a ◽

2020 ◽

Vol 83 (S1) ◽

pp. 189 ◽

Cited By ~ 1

Author(s):

M. Teresa Farriols ◽

Francesc Ordines ◽

Pierluigi Carbonara ◽

Loredana Casciaro ◽

Manfredi Di Lorenzo ◽

...

Keyword(s):

Spatial Scales ◽

Demersal Fish ◽

Fishing Effort ◽

Bottom Trawl ◽

Fish Diversity ◽

Continuous Increase ◽

Diversity Pattern ◽

Trawl Fishing ◽

The Mediterranean ◽

Spatio Temporal

The high species richness, coupled with high proportion of endemism, makes the Mediterranean one of the world’s ‘biodiversity hotspots’. However, the continuous increase in fisheries in the last few decades has led to the overexploitation of their main commercial stocks. Using fishery-independent data collected under the framework of the MEDITS trawl surveys carried out over the last 20 years, we study the demersal fish diversity pattern in the Mediterranean at a large spatial and temporal scale to determine whether it is being affected by the general fishing overexploitation of the demersal resources. The detected diversity trends are compared with the spatio-temporal variation in bottom trawl fishing effort in the Mediterranean. Our results show a stability and even recovery of demersal fish diversity in the Mediterranean together with higher diversity values on the continental shelves of the Balearic Islands, Sardinia, Sicily and the Aegean Sea. At large temporal and spatial scales, the high diversity of demersal assemblages in the Mediterranean is associated with a reduction in bottom trawl fishing effort. The inclusion of species other than target ones through diversity indices is important in the implementation of an ecosystem-based fisheries management.

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Intertidal zonation patterns of macroinfauna over a range of exposed sandy beaches in south-central Chile

Marine Ecology Progress Series ◽

10.3354/meps101105 ◽

1993 ◽

Vol 101 ◽

pp. 105-118 ◽

Cited By ~ 57

Author(s):

E Jaramillo ◽

A McLachlan ◽

P Coetzee

Keyword(s):

Sandy Beaches ◽

Central Chile ◽

South Central ◽

Intertidal Zonation ◽

Zonation Patterns

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Cardiorespiratory Fitness: Reference on the Six-Minute Walk Test and Oxygen Consumption in Adolescents from South-Central Chile

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052474 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2474

Author(s):

Jaime Vásquez-Gómez ◽

Nelson Gatica Salas ◽

Pedro Jiménez Villarroel ◽

Luis Rojas-Araya ◽

Cesar Faundez-Casanova ◽

...

Keyword(s):

Cardiorespiratory Fitness ◽

Reference Values ◽

Estimation Error ◽

Walk Test ◽

Central Chile ◽

Six Minute Walk Test ◽

Body Adiposity ◽

South Central ◽

Males And Females ◽

Minute Walk

Cardiorespiratory fitness (CRF) provides oxygen to the exercising muscles and is related to body adiposity, with cardiometabolic variables. The aim was to develop reference values and a predictive model of CRF in Chilean adolescents. A total of 741 adolescents of both genders (15.7 years old) participated in a basic anthropometry, performance in the six-minute walk test (SMWT), and in Course Navette was measured. Percentiles were determined for the SMWT, for the V̇O2max, and an equation was developed to estimate it. The validity of the equation was checked using distribution assumptions and the Bland–Altman diagram. The STATA v.14 program was used (p < 0.05). The 50th percentile values for males and females in the SMWT and in the V̇O2max of Course Navette were, respectively, from 607 to 690 and from 630 to 641 m, and from 43.9 to 45 and from 37.5 to 31.5 mlO2·kg·min−1, for the range of 13 to 17 years. For its part, the model to predict V̇O2max incorporated gender, heart rate, height, waist-to-height ratio (WHR), and distance in the SMWT (R2 = 0.62; estimation error = 0.38 LO2·min−1; p <0.001). Reference values can guide physical fitness in Chilean adolescents, and V̇O2max was possible to predict from morphofunctional variables.

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