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De Henricus Baar - One of the best experts on this subject based on the ideXlab platform.

  • dissolved aluminium in the ocean conveyor of the west atlantic ocean effects of the Biological Cycle scavenging sediment resuspension and hydrography
    Marine Chemistry, 2015
    Co-Authors: Rob Middag, M M P Van Hulten, H M Van Aken, M J A Rijkenberg, Loes J A Gerringa, P Laan, De Henricus Baar
    Abstract:

    The concentrations of dissolved aluminium (dissolved Al) were studied along the West Atlantic GEOTRACES GA02 transect from 64 degrees N to 50 degrees S. Concentrations ranged from similar to 0.5 nmol kg(-1) in the high latitude surface waters to similar to 48 nmol kg(-1) in surface waters around 25 degrees N. Elevated surface water concentrations due to atmospheric dust loading have little influence on the deep water distribution. However, just below the thermocline, both Northern and Southern Hemisphere Subtropical Mode Waters are elevated in Al, most likely related to atmospheric dust deposition in the respective source regions. In the deep ocean, high concentrations of up to 35 nmol kg(-1). were observed in North Atlantic Deep Water as a result of Al input via sediment resuspension. Comparatively low deep water concentrations were associated with water masses of Antarctic origin. During water mass advection, Al loss by scavenging overrules input via remineralisation and sediment resuspension at the basin wide scale. Nevertheless, sediment resuspension is more important than previously realised for the deep ocean Al distribution and even more intensive sampling is needed in bottom waters to constrain the spatial heterogeneity in the global deep ocean. This thus far longest (17,500 km) full depth ocean section shows that the distribution of Al can be explained by its input sources and the combination of association with particles and release from those particles at depth, the latter most likely when the particles remineralise. The association of Al with particles can be due to incorporation of Al into biogenic silica or scavenging of Al onto biogenic particles. The interaction between Al and biogenic particles can lead to the coupled cycling of Al and silicate that is observed in some ocean regions. However, in other regions this coupling is not observed due to (i) advective processes bringing in older water masses that are depleted in Al, (ii) unfavourable scavenging conditions in the water column, (iii) low surface concentrations of Al or (iv) additional Al sources, notably sediment resuspension. (C) 2015 Elsevier B.V. All rights reserved.

  • dissolved aluminium in the ocean conveyor of the west atlantic ocean effects of the Biological Cycle scavenging sediment resuspension and hydrography
    Marine Chemistry, 2015
    Co-Authors: Rob Middag, M M P Van Hulten, H M Van Aken, M J A Rijkenberg, Loes J A Gerringa, P Laan, De Henricus Baar
    Abstract:

    The concentrations of dissolved aluminium (dissolved Al) were studied along the West Atlantic GEOTRACESGA02 transect from 64°N to 50°S. Concentrations ranged from~0.5 nmol kg-1 in the high latitude surface watersto ~48 nmol kg-1 in surfacewaters around 25°N. Elevated surfacewater concentrations due to atmospheric dustloading have little influence on the deep water distribution. However, just belowthe thermocline, both Northernand Southern Hemisphere Subtropical Mode Waters are elevated in Al, most likely related to atmospheric dustdeposition in the respective source regions.In the deep ocean, high concentrations of up to 35 nmol kg-1 were observed in North Atlantic DeepWater as aresult of Al input via sediment resuspension. Comparatively lowdeepwater concentrationswere associatedwithwater masses of Antarctic origin. During water mass advection, Al loss by scavenging overrules input viaremineralisation and sediment resuspension at the basin wide scale. Nevertheless, sediment resuspension ismore important than previously realised for the deep ocean Al distribution and even more intensive samplingis needed in bottom waters to constrain the spatial heterogeneity in the global deep ocean.This thus far longest (17,500 km) full depth ocean section shows that the distribution of Al can be explained by itsinput sources and the combination of association with particles and release from those particles at depth, thelattermost likelywhen the particles remineralise. The association of Alwith particles can be due to incorporationof Al into biogenic silica or scavenging of Al onto biogenic particles. The interaction between Al and biogenicparticles can lead to the coupled cycling of Al and silicate that is observed in some ocean regions. However, inother regions this coupling is not observed due to (i) advective processes bringing in older water masses thatare depleted in Al, (ii) unfavourable scavenging conditions in the water column, (iii) low surface concentrationsof Al or (iv) additional Al sources, notably sediment resuspension.

Xavier Turon - One of the best experts on this subject based on the ideXlab platform.

  • year round reproduction in a seasonal sea Biological Cycle of the introduced ascidian styela plicata in the western mediterranean
    Marine Biology, 2013
    Co-Authors: Carmen M Pineda, Susanna Lopezlegentil, Xavier Turon
    Abstract:

    The widely introduced ascidian Styela plicata is very common in the Western Mediterranean, an area that can act as a source for secondary introductions due to its high shipping activity. In order to understand the potential of this species to colonize new habitats, its reproductive features were assessed in the Western Mediterranean by means of monthly monitoring of two populations (Vilanova i la Geltru 41°12′53″N, 1°44′11″E; Blanes 41°40′29″N, 2°47′56″E) from January 2009 to December 2010. The reproductive activity of this species was assessed through gonad histology and a gonad index. Population size-structure was measured monthly in order to study recruitment dynamics. No clear seasonal pattern was observed, and mature gametes and recruits were present all year long. Spawning was potentially continuous, although it seemed punctuated with pulses of gamete release, particularly in spring. A prolonged reproductive period is likely to confer a competitive advantage on S. plicata in temperate seas, where most species reproduce seasonally, and may promote recurrent introductions as larvae are available for settlement on transport vectors over much of the year.

Rogel Zambrano, Jose Guillermo - One of the best experts on this subject based on the ideXlab platform.

  • Ciclo biológico de Diaspis echinocacti ( Bouché) (Hemiptera: Diaspididae) en Tuna Opuntia ficus-índica (L) Miller bajo condiciones de laboratorio
    'Universidad Nacional Agraria la Molina', 2020
    Co-Authors: Rogel Zambrano, Jose Guillermo
    Abstract:

    Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en EntomologíaLos objetivos fueron determinar el ciclo biológico de Diaspis echiocacti (Bouché), (Hemiptera: Diaspididae) sobre tuna (Opuntia ficus- índica), en el laboratorio de Ecología de insectos de la Universidad Nacional Agraria La Molina, bajo condiciones de laboratorio en invierno (junio – septiembre del 2018) y otoño (marzo – junio del 2019) con temperaturas de 21.1±1.5°C; 70±4 %HR y 27±2°C; 80±2 %HR respectivamente y determinar la variación del ciclo biológico en las dos épocas del año. En el presente estudio el material biológico (cladodios de tuna infestados por la escama Diaspis echinocacti) fueron colectados de los campos de la Universidad Nacional Agraria La Molina, material biológico que se utilizó para la crianza masal y para estudiar el ciclo biológico. En referencia al ciclo biológico de D. echinocacti se realizaron dos generaciones (invierno y otoño), sobre cuatro cladodios de tuna (repeticiones); que fueron destinados para la crianza y evaluación de cada estado y estadio de desarrollo. El parámetro usado para conocer el período de cada estado y estadio, fue el número de días y se determinó por la presencia de las exuvias. Los estados evaluados fueron: periodo de incubación de huevo, estadio ninfa I (migrante y sedentario), ninfa II, hembra joven, hembra adulta. Además, se evaluaron otros parámetros biológicos como: capacidad de oviposición, ritmo de oviposición y longevidad. Para los machos los estados evaluados fueron: huevo, ninfa I, ninfa II, prepupa, pupa y adulto. El período de incubación de huevos es el mismo para ambos sexos, con un tiempo promedio de 3.80 días en invierno y 2.0 días en otoño. La duración promedio en días para los estadios ninfales I y II son ídem para machos y hembras. Los valores para invierno son 10.75 y 12.5 días; en otoño 9.0 y 9.0 días para la ninfa I y ninfa II respectivamente. Para la época de invierno se registraron los valores para hembra joven de 17.5 días y para hembra adulta de 8.5 días. En cuanto a otoño se determinaron los valores de 14 días y 5.75 días para hembra joven y hembra adulta respectivamente. Asimismo, el ciclo biológico de D. echinocacti en invierno y otoño tiene una duración de 53.05; 39.75 días para hembras y de 51.05; 37.25 días para machos. Los estados de desarrollo del macho: prepupa, 10.25 y 6.75 días; pupa, 10.5 y 8.5 días en invierno y otoño respectivamente y para el macho adulto fue 3.25 días en invierno y de 2.0 días en otoño. La capacidad de oviposición fue de 120 ±30 huevos por hembra en y una longevidad de 44.75 días promedio en otoño. Entre sus controladores observados y recuperados del material de campo se tuvo a parasitoides del genero Aphytis y Encarsia de la familia Aphelinidae y dos predadores Coccidophilus occidentales (González) y Rhyzobius lophantae (Blaisdell) de la familia CoccinellidaeThe objectives were to determine the Biological Cycle of Diaspis echiocacti (Bouché), (Hemiptera: Diaspididae) on prickly pear (Opuntia ficus-indica), in the laboratory of Insect Ecology of the Universidad Nacional Agraria La Molina, under laboratory conditions in winter ( june - september 2018) and autumn (march - june 2019) with temperatures of 21.1 ± 1.5 ° C; 70 ± 4% RH and 27 ± 2 ° C; 80 ± 2% RH respectively and determine the variation of the Biological Cycle at the two times of the year. In the present study, the Biological material (prickly pear cladodes infested by the Diaspis echinocacti scale) were collected from the fields of the Universidad Nacional Agraria La Molina, Biological material that was used for mass rearing and to study the Biological Cycle. In reference to the Biological Cycle of D. echinocacti, two generations were carried out (winter and autumn), on four prickly pear cladodes (repetitions); that were intended for the upbringing and evaluation of each state and stage of development. The parameters used to know the duration of each of the state and stages were the number of days determined by the presence of the exuviae. The female states evaluated were: the incubation period, nymph stages I (migrant and sedentary) and II, young, and adult female. In addition, other Biological characters such as: oviposition capacity, oviposition rate and longevity, were evaluated. For males, the evaluated states were: egg, nymph I, nymph II, prepupa, pupa and adult.The incubation period were the same for both sexes, with an average time of 3.8 days in winter and 2.0 days in autumn. The average duration in days for nymphal stages I and II are close for males and females. Winter values are 10.8 and 12.5 days; in autumn 9.0 and 9.0 days for nymph I and nymph II, respectively. For the winter season, values were recorded for young females of 17.5 days and for adult females of 8.5 days. As for autumn, the values of 14 days and 5.8 days were determined for young females and adult females, respectively. Likewise, the Biological Cycle of D. echinocacti in winter and autumn has a duration of 53.1; 39.8 days for females and 51.1; 37.3 days for males. The stages of development of the male: prepupa, 10.3 and 6.8 days; pupa, 10.5 and 8.5 days in winter and autumn respectively and for the adult males it was 3.3 days in winter and 2.0 days in autumn. The oviposition capacity was 120 ± 30 eggs per female and an average longevity of 44.8 days in autumn. Among its controllers observed and recovered from the field material were parasitoids of the genus Aphytis and Encarsia of the Aphelinidae hymenopterous family and two predators Coccidophilus occidentales (González) and Rhyzobius lophantae (Blaisdell) of the Coccinellidae family.Tesi

  • Ciclo biológico de Diaspis echinocacti ( Bouché) (Hemiptera: Diaspididae) en Tuna Opuntia ficus-índica (L) Miller bajo condiciones de laboratorio
    'Baishideng Publishing Group Inc.', 2020
    Co-Authors: Rogel Zambrano, Jose Guillermo
    Abstract:

    Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en EntomologíaLos objetivos fueron determinar el ciclo biológico de Diaspis echiocacti (Bouché), (Hemiptera: Diaspididae) sobre tuna (Opuntia ficus- índica), en el laboratorio de Ecología de insectos de la Universidad Nacional Agraria La Molina, bajo condiciones de laboratorio en invierno (junio – septiembre del 2018) y otoño (marzo – junio del 2019) con temperaturas de 21.1±1.5°C; 70±4 %HR y 27±2°C; 80±2 %HR respectivamente y determinar la variación del ciclo biológico en las dos épocas del año. En el presente estudio el material biológico (cladodios de tuna infestados por la escama Diaspis echinocacti) fueron colectados de los campos de la Universidad Nacional Agraria La Molina, material biológico que se utilizó para la crianza masal y para estudiar el ciclo biológico. En referencia al ciclo biológico de D. echinocacti se realizaron dos generaciones (invierno y otoño), sobre cuatro cladodios de tuna (repeticiones); que fueron destinados para la crianza y evaluación de cada estado y estadio de desarrollo. El parámetro usado para conocer el período de cada estado y estadio, fue el número de días y se determinó por la presencia de las exuvias. Los estados evaluados fueron: periodo de incubación de huevo, estadio ninfa I (migrante y sedentario), ninfa II, hembra joven, hembra adulta. Además, se evaluaron otros parámetros biológicos como: capacidad de oviposición, ritmo de oviposición y longevidad. Para los machos los estados evaluados fueron: huevo, ninfa I, ninfa II, prepupa, pupa y adulto. El período de incubación de huevos es el mismo para ambos sexos, con un tiempo promedio de 3.80 días en invierno y 2.0 días en otoño. La duración promedio en días para los estadios ninfales I y II son ídem para machos y hembras. Los valores para invierno son 10.75 y 12.5 días; en otoño 9.0 y 9.0 días para la ninfa I y ninfa II respectivamente. Para la época de invierno se registraron los valores para hembra joven de 17.5 días y para hembra adulta de 8.5 días. En cuanto a otoño se determinaron los valores de 14 días y 5.75 días para hembra joven y hembra adulta respectivamente. Asimismo, el ciclo biológico de D. echinocacti en invierno y otoño tiene una duración de 53.05; 39.75 días para hembras y de 51.05; 37.25 días para machos. Los estados de desarrollo del macho: prepupa, 10.25 y 6.75 días; pupa, 10.5 y 8.5 días en invierno y otoño respectivamente y para el macho adulto fue 3.25 días en invierno y de 2.0 días en otoño. La capacidad de oviposición fue de 120 ±30 huevos por hembra en y una longevidad de 44.75 días promedio en otoño. Entre sus controladores observados y recuperados del material de campo se tuvo a parasitoides del genero Aphytis y Encarsia de la familia Aphelinidae y dos predadores Coccidophilus occidentales (González) y Rhyzobius lophantae (Blaisdell) de la familia CoccinellidaeThe objectives were to determine the Biological Cycle of Diaspis echiocacti (Bouché), (Hemiptera: Diaspididae) on prickly pear (Opuntia ficus-indica), in the laboratory of Insect Ecology of the Universidad Nacional Agraria La Molina, under laboratory conditions in winter ( june - september 2018) and autumn (march - june 2019) with temperatures of 21.1 ± 1.5 ° C; 70 ± 4% RH and 27 ± 2 ° C; 80 ± 2% RH respectively and determine the variation of the Biological Cycle at the two times of the year. In the present study, the Biological material (prickly pear cladodes infested by the Diaspis echinocacti scale) were collected from the fields of the Universidad Nacional Agraria La Molina, Biological material that was used for mass rearing and to study the Biological Cycle. In reference to the Biological Cycle of D. echinocacti, two generations were carried out (winter and autumn), on four prickly pear cladodes (repetitions); that were intended for the upbringing and evaluation of each state and stage of development. The parameters used to know the duration of each of the state and stages were the number of days determined by the presence of the exuviae. The female states evaluated were: the incubation period, nymph stages I (migrant and sedentary) and II, young, and adult female. In addition, other Biological characters such as: oviposition capacity, oviposition rate and longevity, were evaluated. For males, the evaluated states were: egg, nymph I, nymph II, prepupa, pupa and adult.The incubation period were the same for both sexes, with an average time of 3.8 days in winter and 2.0 days in autumn. The average duration in days for nymphal stages I and II are close for males and females. Winter values are 10.8 and 12.5 days; in autumn 9.0 and 9.0 days for nymph I and nymph II, respectively. For the winter season, values were recorded for young females of 17.5 days and for adult females of 8.5 days. As for autumn, the values of 14 days and 5.8 days were determined for young females and adult females, respectively. Likewise, the Biological Cycle of D. echinocacti in winter and autumn has a duration of 53.1; 39.8 days for females and 51.1; 37.3 days for males. The stages of development of the male: prepupa, 10.3 and 6.8 days; pupa, 10.5 and 8.5 days in winter and autumn respectively and for the adult males it was 3.3 days in winter and 2.0 days in autumn. The oviposition capacity was 120 ± 30 eggs per female and an average longevity of 44.8 days in autumn. Among its controllers observed and recovered from the field material were parasitoids of the genus Aphytis and Encarsia of the Aphelinidae hymenopterous family and two predators Coccidophilus occidentales (González) and Rhyzobius lophantae (Blaisdell) of the Coccinellidae family

Marco Fornaciari - One of the best experts on this subject based on the ideXlab platform.

  • climatic indices in the interpretation of the phenological phases of the olive in mediterranean areas during its Biological Cycle
    Climatic Change, 2013
    Co-Authors: Fabio Orlandi, H Garciamozo, Ben A Dhiab, Carmen Galan, M Msallem, Bruno Romano, Mounir Abichou, Eugenio Dominguezvilches, Marco Fornaciari
    Abstract:

    The present study implemented a regional phenological model that was derived through the growing season index and adapted to a widespread Mediterranean species, the olive (Olea europaea L.). This model considers not only individual phenological events, but also the main vegetative and reproductive phenological phases of the species, in an integrated Biological approach. The regional model generally does not need to include specific meteorological variables calculated as weekly or monthly averages which could limit the extrapolation over large areas. The main climatic limitations of the olive cultivation areas in the south Mediterranean at latitudes around 10° (practically speaking, the geographical limits of the olive) are estimated here. This analysis uses information relating to local climatic changes over the last two decades (1990–1999, 2000–2009) to provide interpretations of the temperature, solar radiation rate, and evapotranspiration trends. This has allowed creation of a Mediterranean phenological model adapted to the olive, which presents the contemporary climate requirements during winter and the warm summer season. The climate analysis and comparisons of these two decades has allowed us to reveal a reduction in the index according to the minimum temperature, which has particular consequences in the northern monitoring areas. This phenomenon appears to present new positive scenarios for the future regarding a northward shift of olive cultivation areas, due to the potential enlargement of the growing season in winter. However, negative scenarios can also be foreseen in consideration of the failure to satisfy the minimum chilling requirements in the traditional southern cultivation areas of the olive.

M M P Van Hulten - One of the best experts on this subject based on the ideXlab platform.

  • dissolved aluminium in the ocean conveyor of the west atlantic ocean effects of the Biological Cycle scavenging sediment resuspension and hydrography
    Marine Chemistry, 2015
    Co-Authors: Rob Middag, M M P Van Hulten, H M Van Aken, M J A Rijkenberg, Loes J A Gerringa, P Laan, De Henricus Baar
    Abstract:

    The concentrations of dissolved aluminium (dissolved Al) were studied along the West Atlantic GEOTRACES GA02 transect from 64 degrees N to 50 degrees S. Concentrations ranged from similar to 0.5 nmol kg(-1) in the high latitude surface waters to similar to 48 nmol kg(-1) in surface waters around 25 degrees N. Elevated surface water concentrations due to atmospheric dust loading have little influence on the deep water distribution. However, just below the thermocline, both Northern and Southern Hemisphere Subtropical Mode Waters are elevated in Al, most likely related to atmospheric dust deposition in the respective source regions. In the deep ocean, high concentrations of up to 35 nmol kg(-1). were observed in North Atlantic Deep Water as a result of Al input via sediment resuspension. Comparatively low deep water concentrations were associated with water masses of Antarctic origin. During water mass advection, Al loss by scavenging overrules input via remineralisation and sediment resuspension at the basin wide scale. Nevertheless, sediment resuspension is more important than previously realised for the deep ocean Al distribution and even more intensive sampling is needed in bottom waters to constrain the spatial heterogeneity in the global deep ocean. This thus far longest (17,500 km) full depth ocean section shows that the distribution of Al can be explained by its input sources and the combination of association with particles and release from those particles at depth, the latter most likely when the particles remineralise. The association of Al with particles can be due to incorporation of Al into biogenic silica or scavenging of Al onto biogenic particles. The interaction between Al and biogenic particles can lead to the coupled cycling of Al and silicate that is observed in some ocean regions. However, in other regions this coupling is not observed due to (i) advective processes bringing in older water masses that are depleted in Al, (ii) unfavourable scavenging conditions in the water column, (iii) low surface concentrations of Al or (iv) additional Al sources, notably sediment resuspension. (C) 2015 Elsevier B.V. All rights reserved.

  • dissolved aluminium in the ocean conveyor of the west atlantic ocean effects of the Biological Cycle scavenging sediment resuspension and hydrography
    Marine Chemistry, 2015
    Co-Authors: Rob Middag, M M P Van Hulten, H M Van Aken, M J A Rijkenberg, Loes J A Gerringa, P Laan, De Henricus Baar
    Abstract:

    The concentrations of dissolved aluminium (dissolved Al) were studied along the West Atlantic GEOTRACESGA02 transect from 64°N to 50°S. Concentrations ranged from~0.5 nmol kg-1 in the high latitude surface watersto ~48 nmol kg-1 in surfacewaters around 25°N. Elevated surfacewater concentrations due to atmospheric dustloading have little influence on the deep water distribution. However, just belowthe thermocline, both Northernand Southern Hemisphere Subtropical Mode Waters are elevated in Al, most likely related to atmospheric dustdeposition in the respective source regions.In the deep ocean, high concentrations of up to 35 nmol kg-1 were observed in North Atlantic DeepWater as aresult of Al input via sediment resuspension. Comparatively lowdeepwater concentrationswere associatedwithwater masses of Antarctic origin. During water mass advection, Al loss by scavenging overrules input viaremineralisation and sediment resuspension at the basin wide scale. Nevertheless, sediment resuspension ismore important than previously realised for the deep ocean Al distribution and even more intensive samplingis needed in bottom waters to constrain the spatial heterogeneity in the global deep ocean.This thus far longest (17,500 km) full depth ocean section shows that the distribution of Al can be explained by itsinput sources and the combination of association with particles and release from those particles at depth, thelattermost likelywhen the particles remineralise. The association of Alwith particles can be due to incorporationof Al into biogenic silica or scavenging of Al onto biogenic particles. The interaction between Al and biogenicparticles can lead to the coupled cycling of Al and silicate that is observed in some ocean regions. However, inother regions this coupling is not observed due to (i) advective processes bringing in older water masses thatare depleted in Al, (ii) unfavourable scavenging conditions in the water column, (iii) low surface concentrationsof Al or (iv) additional Al sources, notably sediment resuspension.