261 research outputs found
Some observations on the biology of sardine (Sardina pilchardus Walb.) off Galicia NW Spain
6392 specimen of sardines were sampled during the period 1980-1984. The spawning
season was ca1culated from the monthly percentages of mature individuals, gonadosomatic index, condition factor and viscera1 fat. The size and age at first maturation and the size/weight ratio were calculated.Pendant la periode 1980-1984 des echantillonages biologiques regulieres sur
la sardine ont ete realises et 6932 exemplaires ont été examinées. On determine
la saison de ponte a partir de l'evolution mensuelle du pourcentage des individus
mûrs et de la variation du l'indice gonadosomatique, le facteur de condition
et la graisse viscerale. On calcule aussi la taille et l'age de premiere maturation
et les equations taille/poid vive et poid eviscere
Estimates of the sardine spawning stock biomass off the Galician and Cantabrian coasts
From the months of April to May, a simultaneaus daily egg
production method and acoustic surveys were carried out off the
Ga1ician and Cantabrian shelf waters for the purpose of sardine
spawning biomass estimation. These surveys, were coordinated on
a temporal-spatial scale using two ships, the R/V "Investigador
S." doing the egg survey and R/V "Ignat Pavlyunchenkov", the
acoustic tracking.
The present document presents the results of sardine biomass
estimates from the respective stock evaluation techniques
applied: DEPM and acoustics, and analyzes comparatively the
results of both approaches
The energy requirements of a developed world
Through history, special attention has been paid to the study of the relationship between the energy use of a country and its level of development. While the interest of this research area is unquestionable, the energy indicators commonly used (e.g. total primary energy) are problematic. In the current context of globalization, the energy used by a country is not anymore a suitable indicator for measuring the total energy requirements associated with its level of development; the significant variable is the energy consumed worldwide to produce the goods and services demanded by that country, i.e. its energy footprint. In this study, we compare the human development index of 40 countries with their total primary energy demand and total primary energy footprint for the period 1995-2008. The results show that the total primary energy demand underestimates the energy required to maintain a high level of development, since a significant part of the energy used by emerging countries is being increasingly devoted to sustain the welfare of developed countries by means of international trade. We also find that the minimum total primary energy footprint per capita to achieve a high level of development is 33% higher than current world's per capita energy use. (C) 2016 The Authors. Published by Elsevier Inc. on behalf of International Energy Initiative.Inaki Arto thanks financial support by the Seventh Framework Program (FP7) projects COMPLEX (no. 308601) and FLAGSHIP (no. 320330). Inigo Capellan-Perez is grateful for financial support received from Fundacion Repsol under the Low Carbon Programme (www.lowcarbonprogramme.org). The authors express their gratitude to Marco Vinicio Sanchez-Cantillo from the United Nations Department of Economic and Social Affairs for providing data series of the human development index, and to Gautam Dutt for his useful comments to improve the last version of the manuscript
Contribución al conocimiento de la biología de la sardina de Galicia
En el período de 1980 a 1982, se realizaron en el Laboratorio de Vigo 53 muestreos
biológicos de sardina y una campaña de investigación acústica, examinándose
un total de 4368 ejemplares. Con los datos obtenidos se calculó la talla
de primera maduración con valores de 14.5 cm para las hembras, 14 cm para
los machos y 14.5 cm el valor de ambos sexos. La edad de primera maduración
se sitúa en 1.3 años.
La época de puesta es amplia, abarcando de diciembre a mayo con un período
de reposo total de junio a septiembre.
La proporción de sexos se sitúa alrededor del 50% a lo largo de los tres años.
Aparecen variaciones en el porcentaje de hembras por edad en los individuos
adultos.
Se calculó la relación talla/peso para valores de peso vivo y peso eviscerado.During the period 1980-1982 a total of 4368 individuals of pilchard coming
from 53 biological samples and acoustic survey were examined. It was calculated
the first maturity length with values of 14.5 cm for females, 14 cm for males
and 14.5 cm for both sexes. The corresponding age is 1.3 years.
The spawning season is rather wide, from December to May with a clear resting
period between June and September.
The sex ratio is quite constant, 1: 1, along the three years of the study. There
are some variations in the porcentage of females by age in the adults age groups.
The lenght/weight relationship for gutted and ungutted pilchard were also
calculated.Versión del editor0,000
The egg production method applied to the spawning biomass estimation of sardine, Sardina pilchardus (Walb.), on the North Atlantic Spanish coast
During April-May 1988, an Egg Production Method Cruise was carried out with the
purpose of evaluating the spawning biomass of the sardine, Sardina pilchardus
(Walb.), from the Galician and Cantabrian coasts of Spain. This cruise was coordinated
with the acoustical evaluation of this stock on board the R/V Cornide de Saavedra.
The area covered extends from the Spanish-Portuguese border (41º 55' N) to the
Spanish-French border (1º 58' W). Vertical plankton tows at 524 stations were distributed
over the continental shelf and slope water in a 6 X 6 mile grid, with a 6 X 3 mile
grid in areas of more intense spawning, to estimate the daily egg production parameter.
A total of 44 epipelagic trawls were done in order to estimate the biological parameter
relative to the adult population, that is, average female weight, batch fecundity, spawning
fraction and sex ratio.
The suruey area was post-stratified into three regions and the spawning biomass was
estimated for each region. The sum of the three spawning biomass estimates was the total
spawning biomass for the survey area. Three regions were established by differentiated
adult parameters, such as average female weight in conjunction with the considered
acoustical divisions. These regions correspond to the Galician coast (I), the western Cantabrian
area (II) and the eastern sector of the Cantabrian coast (III).Desde abril a mayo de 1988 se aplica el Método de Producción Diaria de Huevos con
el objetivo de estimar la biomasa reproductora de la sardina noratlántica española,
Sardina pilchardus (Walb.), comprendida en el área de las costas de Calicia y del
Cantábrico. Esta campaña fue realizada coordinadamente con la campaña de evaluación
acústica de pelágicos a bordo del B/O Comide de Saavedra.
El área de cobertura se extiende desde la frontera luso-española (41º 55' N) hasta la
frontera con Francia (1º 58' O). Se muestrearon 524 estaciones para la recogida de
muestras planctónicas a lo largo de la plataforma y talud en un mallaje de estaciones de
6 X 6 millas náuticas, y en zonas de mayor abundancia de huevos en 6 X 3, con el
propósito de estimar la producción diaria de huevos de sardina.
Se llevaron a cabo un total de 44 pescas epipelágicas con el fin de estimar los parámetros
biológicos y reproductivos de la población de adultos, como son el peso medio de
las hembras, fecundidad parcial, fracción de hembras en puesta y proporción de sexos.
El área muestreada fue post-estratificada en tres regiones y, consiguientemente, la
biomasa reproductora estimada para cada una de las mismas. La biomasa reproductora
total se logra con la suma de cada una de las biomasas por región. El criterio de
estratificación por regiones se basa en la diferenciación zonal de los parámetros de adultos,
como es el peso medio de las hembras, coincidiendo con las divisiones acústicas
preestablecidas. Estas regiones corresponden a las costas de Galicia (I), Cantábrico occidental
(II) y Cantábrico oriental (III).Versión del editor0,000
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