Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary

Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary

From June 1998 to May 1999, the water temperature, salinity and turbidity, together with the macrofaunal (nekton and hyperbenthos) abundance, biomass and number of species, were estimated in the Guadalquivir estauary at five sampling stations (8, 20, 30, 40 and 50 km from the river mouth). Samples w...

সম্পূর্ণ বিবরণ

সংরক্ষণ করুন:
গ্রন্থ-পঞ্জীর বিবরন
প্রধান লেখক: Baldo, F, Cuesta, JA, Fernández-Delgado, C, Drake, P
বিন্যাস: Online
ভাষা:eng
প্রকাশিত: Iniversidad Autónoma de Baja California 2005
অনলাইন ব্যবহার করুন:https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/48
ট্যাগগুলো: ট্যাগ যুক্ত করুন
কোনো ট্যাগ নেই, প্রথমজন হিসাবে ট্যাগ করুন!
id oai:cienciasmarinas.com.mx:article-48
record_format ojs
institution Ciencias Marinas
collection OJS
language eng
format Online
author Baldo, F
Cuesta, JA
Fernández-Delgado, C
Drake, P
spellingShingle Baldo, F
Cuesta, JA
Fernández-Delgado, C
Drake, P
Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary
author_facet Baldo, F
Cuesta, JA
Fernández-Delgado, C
Drake, P
author_sort Baldo, F
title Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary
title_short Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary
title_full Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary
title_fullStr Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary
title_full_unstemmed Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary
title_sort effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the guadalquivir estuary
description From June 1998 to May 1999, the water temperature, salinity and turbidity, together with the macrofaunal (nekton and hyperbenthos) abundance, biomass and number of species, were estimated in the Guadalquivir estauary at five sampling stations (8, 20, 30, 40 and 50 km from the river mouth). Samples were taken from an anchored boat by using nets with a 1-mm mesh. There was a horizontal salinity gradient along the estuary: monthly mean salinities ranged from 17 to 27 at the outermost sampling station, whilst salinity was rarely higher than 4 in the inner estuary. Water temperature was homogenous throughout the estuary, with maximum values in summer (28ºC) and minimum values in winter (10ºC). Turbidity was also relatively homogenous throughout the estuary, with a maximum in winter (362 NTU) and a minimum in summer (10 NTU). Maximum turbidity occurred in the zone where seawater and freshwater merge. Results of stepwise multiple regression analysis indicated that both the distance to the river mouth and the freshwater input (in the previous month) from the Alcalá del Río dam (110 km from the river mouth) explained 70% of the variance in salinity, but that the freshwater input only explained 17% of the variance respecin water temperature and turbidity. Salinity explained 50% of the variance in the number of species, whereas salinity and temperature were the environmental variables that controlled the macrofaunal abundance and biomass. Salinity and temperature together explained 75% and 71% of the variance for nekton abundance and biomass, respectively, and 54% and 48% of the variance for the abundance and biomass of hyperbenthos, respectively. Salinity was, in all cases, the individual variable that explained the highest portion of variance.
publisher Iniversidad Autónoma de Baja California
publishDate 2005
url https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/48
_version_ 1715723928223088640
spelling oai:cienciasmarinas.com.mx:article-482019-04-10T17:52:59Z Effect of the regulation of freshwater inflow on the physical-chemical characteristics of water and on the aquatic macrofauna in the Guadalquivir estuary Efecto de la regulación del caudal del Río Guadalquivir sobre las características fisicoquímicas del agua y la macrofauna acuática de su estuario Baldo, F Cuesta, JA Fernández-Delgado, C Drake, P Guadalquivir estuary temperature salinity turbidity nekton hyperbenthos estuario del Guadalquivir temperatura salinidad turbidez necton hiperbentos From June 1998 to May 1999, the water temperature, salinity and turbidity, together with the macrofaunal (nekton and hyperbenthos) abundance, biomass and number of species, were estimated in the Guadalquivir estauary at five sampling stations (8, 20, 30, 40 and 50 km from the river mouth). Samples were taken from an anchored boat by using nets with a 1-mm mesh. There was a horizontal salinity gradient along the estuary: monthly mean salinities ranged from 17 to 27 at the outermost sampling station, whilst salinity was rarely higher than 4 in the inner estuary. Water temperature was homogenous throughout the estuary, with maximum values in summer (28ºC) and minimum values in winter (10ºC). Turbidity was also relatively homogenous throughout the estuary, with a maximum in winter (362 NTU) and a minimum in summer (10 NTU). Maximum turbidity occurred in the zone where seawater and freshwater merge. Results of stepwise multiple regression analysis indicated that both the distance to the river mouth and the freshwater input (in the previous month) from the Alcalá del Río dam (110 km from the river mouth) explained 70% of the variance in salinity, but that the freshwater input only explained 17% of the variance respecin water temperature and turbidity. Salinity explained 50% of the variance in the number of species, whereas salinity and temperature were the environmental variables that controlled the macrofaunal abundance and biomass. Salinity and temperature together explained 75% and 71% of the variance for nekton abundance and biomass, respectively, and 54% and 48% of the variance for the abundance and biomass of hyperbenthos, respectively. Salinity was, in all cases, the individual variable that explained the highest portion of variance. La temperatura, salinidad y turbidez del agua en el estuario del Guadalquivir, así como la abundancia, biomasa y número de especies de su macrofauna acuática (necton e hiperbentos), se estimaron mensualmente, entre junio de 1997 y mayo de 1999, en cinco estaciones de muestreo a 8, 20, 30, 40 y 50 km de la desembocadura utilizando para la toma de muestras un barco angulero provisto de un arte de pesca con malla de 1 mm de luz. En el estuario existió horizontalmente un marcado gradiente salino: la salinidad media mensual osciló habitualmente entre 17 y 27 en la estación más externa, mientras que en la zona más interna raramente sobrepasó 4. La temperatura fue homogénea en todo el estuario, con máximos estivales (28ºC) y mínimos invernales (10ºC). La turbidez también fue relativamente homogénea en todo el estuario, con valores máximos invernales (362 UNT) y mínimos principalmente estivales (10 UNT). Los máximos de turbidez coincidieron con la zona de confluencia del agua marina y dulce. Los resultados de los análisis de regresión múltiple por pasos indican que la distancia a la desembocadura y el caudal medio de agua desembalsada (el mes previo) desde la presa de Alcalá del Río (a 110 km de la desembocadura) explican 70% de la varianza de la salinidad, mientras que el caudal desembalsado apenas explica 17% de la varianza observada en la temperatura y la turbidez del agua. La salinidad explica 50% de la varianza del número de especies, mientras que la salinidad y la temperatura son las variables ambientales que controlan la variación de la abundancia y biomasa de la macrofauna estuárica, llegando a explicar 75% y 71% de la varianza de la abundancia y biomasa de la comunidad nectónica, respectivamente, y 54% y 48% de la varianza de la abundancia y biomasa hiperbentónica, respectivamente. La salinidad fue, en todos los casos, la variable que explicó un mayor porcentaje de la varianza. Iniversidad Autónoma de Baja California 2005-03-06 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Peer-reviewed Article Artículo Arbitrado application/pdf https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/48 10.7773/cm.v31i3.48 Ciencias Marinas; Vol. 31 No. 3 (2005); 467-476 Ciencias Marinas; Vol. 31 Núm. 3 (2005); 467-476 2395-9053 0185-3880 eng https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/48/30

অনুরূপ উপাদানগুলি