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Donald R Strong - One of the best experts on this subject based on the ideXlab platform.

  • hybridization between invasive Spartina densiflora poaceae and native s foliosa in san francisco bay california usa
    American Journal of Botany, 2008
    Co-Authors: Debra R Ayres, Eva Grotkopp, Katherine Zaremba, Christina M Sloop, Michael J Blum, John P Bailey, Carina K Anttila, Donald R Strong
    Abstract:

    Rapid evolution in contemporary time can result when related species, brought together through human-aided introduction, hybridize. The significant evolutionary consequences of post-introduction hybridization range from allopolyploid speciation to extinction of species through genetic amalgamation. Both processes are known to occur in the perennial cordgrass genus, Spartina. Here we report the existence of a third recent Spartina hybridization, discovered in 2002, between introduced S. densiflora and native S. foliosa in San Francisco Bay, California, USA. We used nuclear and chloroplast DNA analysis and nuclear DNA content with chromosome counts to examine plants of morphology intermediate between S. densiflora and S. foliosa in a restored marsh in Marin County, California. We found 32 F(1) diploid hybrids and two triploid plants, all having S. densiflora and S. foliosa as parents; there is also evidence of a genetic contribution of S. alterniflora in some hybrids. None of these hybrids set germinable seed. In 2007 we found a hybrid over 30 miles away in a marsh where both parental species occurred, suggesting hybridization may not be a localized phenomenon. The presence of diploid and triploid hybrids is important because they indicate that several avenues existed that may have given rise to a new allopolyploid species. However, such an event is now unlikely because all hybrids are targets of eradication efforts.

  • spread of exotic cordgrasses and hybrids Spartina sp in the tidal marshes of san francisco bay california usa
    Biological Invasions, 2004
    Co-Authors: Debra R Ayres, Katy Zaremba, Shannon Klohr, Debra L Smith, Donald R Strong
    Abstract:

    Four species of exotic cordgrass (Spartina sp.) occur in the San Francisco estuary in addition to the California native Spartina foliosa. Our goal was to map the location and extent of all non-native Spartina in the estuary. Hybrids of S. alterniflora and S. foliosa are by far the most numerous exotic and are spreading rapidly. Radiating from sites of deliberate introduction, S. alterniflora and hybrids now cover ca. 190 ha, mainly in the South and Central Bay. Estimates of rate of aerial increase range from a constant value to an accelerating rate of increase. This could be due to the proliferation of hybrid clones capable of rapid expansion and having superior seed set and siring abilities. The total coverage of 195 ha by hybrids and other exotic cordgrass species is slightly less than 1% of the Bay's tidal mudflats and marshes. Spartina anglica has not spread beyond its original 1970s introduction site. Spartina densiflora has spread to cover over 5 ha at 3 sites in the Central Bay. Spartina patens has expanded from 2 plants in 1970 to 42 plants at one site in Suisun Bay. Spartina seed floats on the tide, giving it the potential to export this invasion throughout the San Francisco estuary, and to estuaries outside of the Golden Gate. We found isolated plants of S. alterniflora and S. densiflora in outer coast estuaries north of the Bay suggesting the likelihood for the San Francisco Bay populations to found others on the Pacific coast.

  • © 2004 Kluwer Academic Publishers. Printed in the Netherlands. Spread of exotic cordgrasses and hybrids (Spartina sp.) in the
    2003
    Co-Authors: Debra R Ayres, Katy Zaremba, Shannon Klohr, Debra L Smith, Donald R Strong
    Abstract:

    Four species of exotic cordgrass (Spartina sp.) occur in the San Francisco estuary in addition to the California native Spartina foliosa. Our goal was to map the location and extent of all non-native Spartina in the estuary. Hybrids of S. alterniflora and S. foliosa are by far the most numerous exotic and are spreading rapidly. Radiating from sites of deliberate introduction, S. alterniflora and hybrids now cover ca. 190 ha, mainly in the South and Central Bay. Estimates of rate of aerial increase range from a constant value to an accelerating rate of increase. This could be due to the proliferation of hybrid clones capable of rapid expansion and having superior seed set and siring abilities. The total coverage of 195 ha by hybrids and other exotic cordgrass species is slightly less than 1 % of the Bay’s tidal mudflats and marshes. Spartina anglica has not spread beyond its original 1970s introduction site. Spartina densiflora has spread to cover over 5 ha at 3 sites in the Central Bay. Spartina patens has expanded from 2 plants in 1970 to 42 plants at one site in Suisun Bay. Spartina seed floats on the tide, giving it the potential to export this invasion throughout the San Francisco estuary, and to estuaries outside of the Golden Gate. We found isolated plants of S. alterniflora and S. densiflora in outer coast estuaries north of the Bay suggesting the likelihood for the San Francisco Bay populations to found others on the Pacific coast

Debra R Ayres - One of the best experts on this subject based on the ideXlab platform.

  • hybridization between invasive Spartina densiflora poaceae and native s foliosa in san francisco bay california usa
    American Journal of Botany, 2008
    Co-Authors: Debra R Ayres, Eva Grotkopp, Katherine Zaremba, Christina M Sloop, Michael J Blum, John P Bailey, Carina K Anttila, Donald R Strong
    Abstract:

    Rapid evolution in contemporary time can result when related species, brought together through human-aided introduction, hybridize. The significant evolutionary consequences of post-introduction hybridization range from allopolyploid speciation to extinction of species through genetic amalgamation. Both processes are known to occur in the perennial cordgrass genus, Spartina. Here we report the existence of a third recent Spartina hybridization, discovered in 2002, between introduced S. densiflora and native S. foliosa in San Francisco Bay, California, USA. We used nuclear and chloroplast DNA analysis and nuclear DNA content with chromosome counts to examine plants of morphology intermediate between S. densiflora and S. foliosa in a restored marsh in Marin County, California. We found 32 F(1) diploid hybrids and two triploid plants, all having S. densiflora and S. foliosa as parents; there is also evidence of a genetic contribution of S. alterniflora in some hybrids. None of these hybrids set germinable seed. In 2007 we found a hybrid over 30 miles away in a marsh where both parental species occurred, suggesting hybridization may not be a localized phenomenon. The presence of diploid and triploid hybrids is important because they indicate that several avenues existed that may have given rise to a new allopolyploid species. However, such an event is now unlikely because all hybrids are targets of eradication efforts.

  • spread of exotic cordgrasses and hybrids Spartina sp in the tidal marshes of san francisco bay california usa
    Biological Invasions, 2004
    Co-Authors: Debra R Ayres, Katy Zaremba, Shannon Klohr, Debra L Smith, Donald R Strong
    Abstract:

    Four species of exotic cordgrass (Spartina sp.) occur in the San Francisco estuary in addition to the California native Spartina foliosa. Our goal was to map the location and extent of all non-native Spartina in the estuary. Hybrids of S. alterniflora and S. foliosa are by far the most numerous exotic and are spreading rapidly. Radiating from sites of deliberate introduction, S. alterniflora and hybrids now cover ca. 190 ha, mainly in the South and Central Bay. Estimates of rate of aerial increase range from a constant value to an accelerating rate of increase. This could be due to the proliferation of hybrid clones capable of rapid expansion and having superior seed set and siring abilities. The total coverage of 195 ha by hybrids and other exotic cordgrass species is slightly less than 1% of the Bay's tidal mudflats and marshes. Spartina anglica has not spread beyond its original 1970s introduction site. Spartina densiflora has spread to cover over 5 ha at 3 sites in the Central Bay. Spartina patens has expanded from 2 plants in 1970 to 42 plants at one site in Suisun Bay. Spartina seed floats on the tide, giving it the potential to export this invasion throughout the San Francisco estuary, and to estuaries outside of the Golden Gate. We found isolated plants of S. alterniflora and S. densiflora in outer coast estuaries north of the Bay suggesting the likelihood for the San Francisco Bay populations to found others on the Pacific coast.

  • © 2004 Kluwer Academic Publishers. Printed in the Netherlands. Spread of exotic cordgrasses and hybrids (Spartina sp.) in the
    2003
    Co-Authors: Debra R Ayres, Katy Zaremba, Shannon Klohr, Debra L Smith, Donald R Strong
    Abstract:

    Four species of exotic cordgrass (Spartina sp.) occur in the San Francisco estuary in addition to the California native Spartina foliosa. Our goal was to map the location and extent of all non-native Spartina in the estuary. Hybrids of S. alterniflora and S. foliosa are by far the most numerous exotic and are spreading rapidly. Radiating from sites of deliberate introduction, S. alterniflora and hybrids now cover ca. 190 ha, mainly in the South and Central Bay. Estimates of rate of aerial increase range from a constant value to an accelerating rate of increase. This could be due to the proliferation of hybrid clones capable of rapid expansion and having superior seed set and siring abilities. The total coverage of 195 ha by hybrids and other exotic cordgrass species is slightly less than 1 % of the Bay’s tidal mudflats and marshes. Spartina anglica has not spread beyond its original 1970s introduction site. Spartina densiflora has spread to cover over 5 ha at 3 sites in the Central Bay. Spartina patens has expanded from 2 plants in 1970 to 42 plants at one site in Suisun Bay. Spartina seed floats on the tide, giving it the potential to export this invasion throughout the San Francisco estuary, and to estuaries outside of the Golden Gate. We found isolated plants of S. alterniflora and S. densiflora in outer coast estuaries north of the Bay suggesting the likelihood for the San Francisco Bay populations to found others on the Pacific coast

Oscar Iribarne - One of the best experts on this subject based on the ideXlab platform.

Figueroa Clemente, Manuel Enrique - One of the best experts on this subject based on the ideXlab platform.

  • Low genetic diversity contrasts with high phenotypic variability in heptaploid Spartina densiflora populations invading the Pacific coast of North America
    'Wiley', 2018
    Co-Authors: Castillo Segura, Jesús Manuel, Figueroa Clemente, Manuel Enrique, Grewell, Brenda J., Gallego Tévar Blanca, Vallet Dominique, Salmon Armel
    Abstract:

    Species can respond to environmental pressures through genetic and epigenetic changes and through phenotypic plasticity, but few studies have evaluated the relationships between genetic differentiation and phenotypic plasticity of plant species along changing environmental conditions throughout wide latitudinal ranges. We studied inter‐ and intrapopulation genetic diversity (using simple sequence repeats and chloroplast DNA sequencing) and inter‐ and intrapopulation phenotypic variability of 33 plant traits (using field and common‐garden measurements) for five populations of the invasive cordgrass Spartina densiflora Brongn. along the Pacific coast of North America from San Francisco Bay to Vancouver Island. Studied populations showed very low genetic diversity, high levels of phenotypic variability when growing in contrasted environments and high intrapopulation phenotypic variability for many plant traits. This intrapopulation phenotypic variability was especially high, irrespective of environmental conditions, for those traits showing also high phenotypic plasticity. Within‐population variation represented 84% of the total genetic variation coinciding with certain individual plants keeping consistent responses for three plant traits (chlorophyll b and carotenoid contents, and dead shoot biomass) in the field and in common‐garden conditions. These populations have most likely undergone genetic bottleneck since their introduction from South America; multiple introductions are unknown but possible as the population from Vancouver Island was the most recent and one of the most genetically diverse. S. densiflora appears as a species that would not be very affected itself by climate change and sea‐level rise as it can disperse, establish, and acclimate to contrasted environments along wide latitudinal ranges

  • Effects of competition from the invasive Cordgrass Spartina densiflora on Native Atriplex portulacoides
    IJSER Publications, 2014
    Co-Authors: Abbas, Ahmed M., Figueroa Clemente, Manuel Enrique, Rubio Casal, Alfredo Emilio, Alfonso De ,cires Segura, Castillo Segura, Jesús Manuel
    Abstract:

    Invasion by the South American cordgrass Spartina densiflora Brongn. in European salt marshes is causing concern about potential impacts to native plant communities., S. densiflora colonization of mid-marsh habitats may be slowed by native Atriplex portulacoides L., but the mechanism behind this negative interaction is not known. The aim of this work was to study the establishment and growth response of S. densiflora seedlings grow-ing in a competitive environment with mature A. portulacoides plants in controlled greenhouse conditions. With this aim we measured establishment, growth, foliar nutrients, and photosynthetic pigments of S. densiflora plants grown with and without A. portulacoides. Results showed that S. densiflora seedlings readily established in mature stands of A. portulacoides. Every Spartina clump growing with Atriplex survived, producing fewer tillers with simi-lar heights than when growing without competition, which was reflected on lower above-ground biomass. These results indicated that S. densiflora was affected at the above-ground level by the interspecific competition with Atriplex, but the invasive cordgrass was able to keep similar below-ground bio-mass with and without competition, resulting in a decrease of below-ground biomass of Atriplex when competing with Spartina. Our results in green-house controlled conditions were in agreement with our field observations where S. densiflora plants have been observed growing within A. portu-lacoides monospecific communities

  • Gestión de la invasión de la especie invasora Spartina densiflora en las marismas del Golfo de Cádiz. Implicaciones del cambio climático sobre sus respuestas ecofisiológicas
    Grupo de Investigación Gestión Integrada de Áreas Litorales, 2012
    Co-Authors: Mateos Naranjo Enrique, Redondo Gómez Susana, Figueroa Clemente, Manuel Enrique, Cambrollé Silva Jesús, Castellanos Verdugo, Eloy Manuel, Andrades Moreno Luis, Luque C., Barragán Muñoz, Juan Manuel
    Abstract:

    Las marismas son ecosistemas frontera entre los medios terrestre y costero, que se distribuyen a lo largo de los estuarios de latitudes medias y altas de todo el mundo. Se trata de ecosistemas de gran importancia tanto ecológica como medioambiental y socio-económica. A pesar de la importancia de las marismas, son ecosistemas con graves problemas de conservación, derivados principalmente de la actividad humana. Actualmente, la introducción de especies exóticas invasoras está adquiriendo gran peso en la problemática de la conservación de las marismas. La introducción de seres vivos fuera de su área de distribución natural supone, tras la destrucción de los hábitats, el segundo problema ambiental por orden de magnitud que afecta a la Biosfera a escala global. Spartina densiflora, es una gramínea de origen sudamericano, que está invadiendo marismas del norte de América, del norte de África y el suroeste de Europa. En Europa, la presencia de esta especie se restringe al Golfo de Cádiz donde invade muchos estuarios con diferente grado e intensidad de invasión. La invasión de S. densiflora en el Golfo de Cádiz es uno de los problemas de conservación más graves a los que se enfrentan las marismas andaluzas, ya que los efectos deletéreos que se derivan de la invasión de esta especie sobre estos ecosistemas son muy variados: (1) la alteración de la red de drenaje; (2) se dan pérdidas de hábitats debido a su forma de crecimiento; (3) esta pérdida de hábitats incide directamente en la pérdida de riqueza específica y diversidad genotípica. (4) Interfiere en los procesos de sucesión primaria y secundaria; (5) se da la disminución de la tasa de descomposición, de la productividad y de la producción y (6) se ha descrito en especies del género Spartina la intervención en procesos de hibridación con especies nativas, que suponen un grave riesgo ecológico para el ecosistema al generarse híbridos fértiles, de gran capacidad competitiva. En vista de toda la problemática que subyace a la invasión de S. densiflora en los complejos marismeños del Golfo de Cádiz es necesario elaborar un plan de gestión dirigido a luchar eficazmente contra la invasión de esta especie en las marismas andaluzas. Para la elaboración de cualquier programa de gestión de una especie invasora, se marcan diferentes objetivos. Uno de ellos es profundizar en el conocimiento de la biología, ecología y fisiología de la especie objeto de los diferentes programas de gestión. Uno de los aspectos fundamentales a dilucidar es como el Cambio Climático puede afectar a la invasión de esta especie y en que medida las nuevas condiciones ambientales que se darán podrán alterar los patrones de invasión y tolerancia de esta especie. Para lo cual se ha propuesto un trabajo en el que se ha analizado el efecto del incremento del CO2 atmosférico sobre el crecimiento y la fisiología de esta especie invasora. Nuestros resultados mostraron como el incremento del CO2 tendrá un efecto positivo sobre el desarrollo de esta especie lo que supondrá un favorecimiento del potencial invasor de S. densiflora en las marismas del Golfo de Cádiz. Esta información es de gran utilidad para los gestores de los Espacios Naturales Protegidos la cual se tendrá que tener en cuenta en los futuros planes de gestión de las especies exóticas invasoras a la hora de la priorización en la asignación de recursos para el control o erradicación de dichas especies

  • Synergic effect of salinity and CO2 enrichment on growth and photosynthetic responses of the invasive cordgrass Spartina densiflora
    'Oxford University Press (OUP)', 2010
    Co-Authors: Mateos Naranjo Enrique, Redondo Gómez Susana, Álvarez Morales Rosario, Cambrollé Silva Jesús, Gandullo Tovar, Jacinto Manuel, Figueroa Clemente, Manuel Enrique
    Abstract:

    Spartina densiflora is a C4 halophytic species that has proved to have a high invasive potential which derives from its clonal growth and its physiological plasticity to environmental factors, such as salinity. A greenhouse experiment was designed to investigate the synergic effect of 380 and 700 ppm CO2 at 0, 171, and 510 mM NaCl on the growth and the photosynthetic apparatus of S. densiflora by measuring chlorophyll fluorescence parameters, gas exchange and photosynthetic pigment concentrations. PEPC activity and total ash, sodium, potassium, calcium, magnesium, and zinc concentrations were determined, as well as the C/N ratio. Elevated CO 2 stimulated growth of S. densiflora at 0 and 171 mM NaCl external salinity after 90 d of treatment. This growth enhancement was associated with a greater leaf area and improved leaf water relations rather than with variations in net photosynthetic rate (A). Despite the fact that stomatal conductance decreased in response to 700 ppm CO2 after 30 d of treatment, A was not affected. This response of A to elevated CO2 concentration might be explained by an enhanced PEPC carboxylation capacity. On the whole, plant nutrient concentrations declined under elevated CO2, which can be ascribed to the dilution effect caused by an increase in biomass and the higher water content found at 700 ppm CO2. Finally, CO2 and salinity had a marked overall effect on the photochemical (PSII) apparatus and the synthesis of photosynthetic pigments.Ministerio de Ciencia y Tecnología PCI2006-A7-0641Ministerio de Medio Ambiente 042/200

  • El empleo de técnicas de control y erradicación en la lucha contra especies invasoras: conveniencia de la herbivoría como método de bio-control de la invasión de Spartina densiflora brongn. en el Campo de Gibraltar
    Mancomunidad de Municipios del Campo de Gibraltar, 2007
    Co-Authors: Mateos Naranjo Enrique, Redondo Gómez Susana, Castillo Segura, Jesús Manuel, Figueroa Clemente, Manuel Enrique
    Abstract:

    Spartina densiflora es una gramínea procedente de Sudamérica que está invadiendo numerosas marismas mareales en el golfo de Cádiz provocando problemas muy graves para la conservación de estos ecosistemas, como la pérdida de biodiversidad. En el Campo de Gibraltar Spartina densiflora se localiza en las desembocaduras de los ríos Vega y Jara y en el estuario del río Palmones. Conocer el estado de la invasión en estas zonas es de especial relevancia a la hora de optar entre diferentes técnicas de erradicación o control. Mientras en el río Palmones sería factible la eliminación mecánica de los clones de Spartina densiflora, en el caso de los estuarios de los ríos Vega y Jara el empleo de la ganadería como medida de bio-control parece la estrategia más aconsejable. No obstante, la amplia gama de efectos que la presión de la herbivoría provoca sobre las comunidades vegetales y, en concreto, sobre la evolución de especies invasoras hace necesario llevar a cabo estudios detallados sobre la utilidad de la ganadería como herramienta de gestión en materia de especies invasoras

Mateos Naranjo Enrique - One of the best experts on this subject based on the ideXlab platform.

  • Soil phenanthrene phytoremediation capacity in bacteria-assisted Spartina densiflora
    'Elsevier BV', 2019
    Co-Authors: Mesa Marín Jennifer, Mateos Naranjo Enrique, Barcia Piedras, José María, Cox Meana Lucía, Real Ojeda Miguel, Pérez Romero, Jesús Alberto, Navarro Torre Salvadora, Rodríguez Llorente, Ignacio David, Pajuelo Domínguez Eloísa, Parra Martín Raquel
    Abstract:

    Polycyclic aromatic hydrocarbons (PAH) have become a threat for the conservation of wetlands worldwide. The halophyte Spartina densiflora has shown to be potentially useful for soil phenanthrene phytoremediation, but no studies on bacteria-assisted hydrocarbon phytoremediation have been carried out with this halophyte. In this work, three phenanthrene-degrading endophytic bacteria were isolated from S. densiflora tissues and used for plant inoculation. Bacterial bioaugmentation treatments slightly improved S. densiflora growth, photosynthetic and fluorescence parameters. But endophyte-inoculated S. densiflora showed lower soil phenanthrene dissipation rates than non-inoculated S. densiflora (30% below) or even bulk soil (23% less). Our work demonstrates that endophytic inoculation on S. densiflora under greenhouse conditions with the selected PAH-degrading strains did not significantly increase inherent phenanthrene soil dissipation capacity of the halophyte. It would therefore be advisable to provide effective follow-up of bacterial colonization, survival and metabolic activity during phenanthrene soil phytoremediation.Ministerio de Economía y Competitividad CGL2016-75550-RMinisterio de Educación, Cultura y Deporte FPU014/0398

  • Atmospheric CO2 enrichment effect on the Cu-tolerance of the C4 cordgrass Spartina densiflora
    'Elsevier BV', 2018
    Co-Authors: Pérez Romero, Jesús Alberto, Redondo Gómez Susana, Idaszkin, Yanina Lorena, Duarte Bernardo, Baeta Alexandra, Marques, JoÃo Carlos, Caçador Isabel, Mateos Naranjo Enrique
    Abstract:

    A glasshouse experiment was designed to investigate the effect of the co-occurrence of 400 and 700ppm CO2 at 0, 15 and 45mM Cu on the Cu-tolerance of C4 cordgrass species Spartina densiflora, by measuring growth, gas exchange, efficiency of PSII, pigments profiles, antioxidative enzyme activities and nutritional balance. Our results revealed that the rising atmospheric CO2 mitigated growth reduction imposed by Cu in plants grown at 45mM Cu, leading to leaf Cu concentration bellow than 270mgKg-1 Cu, caused by an evident dilution effect. On the other hand, non-CO2 enrichment plants showed leaf Cu concentration values up to 737.5mgKg-1 Cu. Furthermore, improved growth was associated with higher net photosynthetic rate (AN). The beneficial effect of rising CO2 on photosynthetic apparatus seems to be associated with a reduction of stomatal limitation imposed by Cu excess, which allowed these plants to maintain greater iWUE values. Also, plants grown at 45mM Cu and 700ppm CO2, showed higher ETR values and lower energy dissipation, which could be linked with an induction of Rubisco carboxylation and supported by the recorded amelioration of N imbalance. Furthermore, higher ETR values under CO2 enrichment could lead to an additional consumption of reducing equivalents. Idea that was reflected in the lower values of ETRmax/AN ratio, malondialdehyde (MDA) and ascorbate peroxidase (APx), guaiacol peroxidase (GPx) and superoxide dismutase (SOD) activities under Cu excess, which could indicate a lower production of ROS species under elevated CO2 concentration, due to a better use of absorbed energy.info:eu-repo/semantics/publishedVersio

  • Gestión de la invasión de la especie invasora Spartina densiflora en las marismas del Golfo de Cádiz. Implicaciones del cambio climático sobre sus respuestas ecofisiológicas
    Grupo de Investigación Gestión Integrada de Áreas Litorales, 2012
    Co-Authors: Mateos Naranjo Enrique, Redondo Gómez Susana, Figueroa Clemente, Manuel Enrique, Cambrollé Silva Jesús, Castellanos Verdugo, Eloy Manuel, Andrades Moreno Luis, Luque C., Barragán Muñoz, Juan Manuel
    Abstract:

    Las marismas son ecosistemas frontera entre los medios terrestre y costero, que se distribuyen a lo largo de los estuarios de latitudes medias y altas de todo el mundo. Se trata de ecosistemas de gran importancia tanto ecológica como medioambiental y socio-económica. A pesar de la importancia de las marismas, son ecosistemas con graves problemas de conservación, derivados principalmente de la actividad humana. Actualmente, la introducción de especies exóticas invasoras está adquiriendo gran peso en la problemática de la conservación de las marismas. La introducción de seres vivos fuera de su área de distribución natural supone, tras la destrucción de los hábitats, el segundo problema ambiental por orden de magnitud que afecta a la Biosfera a escala global. Spartina densiflora, es una gramínea de origen sudamericano, que está invadiendo marismas del norte de América, del norte de África y el suroeste de Europa. En Europa, la presencia de esta especie se restringe al Golfo de Cádiz donde invade muchos estuarios con diferente grado e intensidad de invasión. La invasión de S. densiflora en el Golfo de Cádiz es uno de los problemas de conservación más graves a los que se enfrentan las marismas andaluzas, ya que los efectos deletéreos que se derivan de la invasión de esta especie sobre estos ecosistemas son muy variados: (1) la alteración de la red de drenaje; (2) se dan pérdidas de hábitats debido a su forma de crecimiento; (3) esta pérdida de hábitats incide directamente en la pérdida de riqueza específica y diversidad genotípica. (4) Interfiere en los procesos de sucesión primaria y secundaria; (5) se da la disminución de la tasa de descomposición, de la productividad y de la producción y (6) se ha descrito en especies del género Spartina la intervención en procesos de hibridación con especies nativas, que suponen un grave riesgo ecológico para el ecosistema al generarse híbridos fértiles, de gran capacidad competitiva. En vista de toda la problemática que subyace a la invasión de S. densiflora en los complejos marismeños del Golfo de Cádiz es necesario elaborar un plan de gestión dirigido a luchar eficazmente contra la invasión de esta especie en las marismas andaluzas. Para la elaboración de cualquier programa de gestión de una especie invasora, se marcan diferentes objetivos. Uno de ellos es profundizar en el conocimiento de la biología, ecología y fisiología de la especie objeto de los diferentes programas de gestión. Uno de los aspectos fundamentales a dilucidar es como el Cambio Climático puede afectar a la invasión de esta especie y en que medida las nuevas condiciones ambientales que se darán podrán alterar los patrones de invasión y tolerancia de esta especie. Para lo cual se ha propuesto un trabajo en el que se ha analizado el efecto del incremento del CO2 atmosférico sobre el crecimiento y la fisiología de esta especie invasora. Nuestros resultados mostraron como el incremento del CO2 tendrá un efecto positivo sobre el desarrollo de esta especie lo que supondrá un favorecimiento del potencial invasor de S. densiflora en las marismas del Golfo de Cádiz. Esta información es de gran utilidad para los gestores de los Espacios Naturales Protegidos la cual se tendrá que tener en cuenta en los futuros planes de gestión de las especies exóticas invasoras a la hora de la priorización en la asignación de recursos para el control o erradicación de dichas especies

  • Synergic effect of salinity and CO2 enrichment on growth and photosynthetic responses of the invasive cordgrass Spartina densiflora
    'Oxford University Press (OUP)', 2010
    Co-Authors: Mateos Naranjo Enrique, Redondo Gómez Susana, Álvarez Morales Rosario, Cambrollé Silva Jesús, Gandullo Tovar, Jacinto Manuel, Figueroa Clemente, Manuel Enrique
    Abstract:

    Spartina densiflora is a C4 halophytic species that has proved to have a high invasive potential which derives from its clonal growth and its physiological plasticity to environmental factors, such as salinity. A greenhouse experiment was designed to investigate the synergic effect of 380 and 700 ppm CO2 at 0, 171, and 510 mM NaCl on the growth and the photosynthetic apparatus of S. densiflora by measuring chlorophyll fluorescence parameters, gas exchange and photosynthetic pigment concentrations. PEPC activity and total ash, sodium, potassium, calcium, magnesium, and zinc concentrations were determined, as well as the C/N ratio. Elevated CO 2 stimulated growth of S. densiflora at 0 and 171 mM NaCl external salinity after 90 d of treatment. This growth enhancement was associated with a greater leaf area and improved leaf water relations rather than with variations in net photosynthetic rate (A). Despite the fact that stomatal conductance decreased in response to 700 ppm CO2 after 30 d of treatment, A was not affected. This response of A to elevated CO2 concentration might be explained by an enhanced PEPC carboxylation capacity. On the whole, plant nutrient concentrations declined under elevated CO2, which can be ascribed to the dilution effect caused by an increase in biomass and the higher water content found at 700 ppm CO2. Finally, CO2 and salinity had a marked overall effect on the photochemical (PSII) apparatus and the synthesis of photosynthetic pigments.Ministerio de Ciencia y Tecnología PCI2006-A7-0641Ministerio de Medio Ambiente 042/200

  • Hacia una metodología de gestión de la especie invasora Spartina densiflora Brongn.: estado de invasión, avances ecofisiológicos y control
    2008
    Co-Authors: Mateos Naranjo Enrique
    Abstract:

    La presente Tesis Doctoral se ha desarrollado teniendo en cuenta los tres objetivos que se marcan como fundamentales para la correcta gestión de una especie invasora (Hedger et al., 2003; Consejería de Media Ambiente, 2006). Así, el primer objetivo de esta Tesis Doctoral es analizar la situación actual del estado de la invasión de Spartina densiflora en las marismas del Golfo de Cádiz integradas d entro de la Red de Espacios Naturales de Andalucía (RENPA). Para la consecución de este primer objetivo se establecen los siguientes objetivos parciales:1. Crear una cartografía a escala de detalle de la invasión de Spartina densiflora en las diferentes marismas del Golfo de Cádiz integradas dentro de la Red de Espacios Naturales de Andalucía (RENPA), mediante el empleo de Sistemas de Información Geográfica (SIG).2. Cuantificar el grado de invasión en cada uno de los diferentes estuarios sometidos a este análisis, identificando aquellos hábitats y especies más afectados por la presencia de Spartina densiflora.3. Cuantificar el efecto potencias de Spartina densiflora sobre la riqueza específica vegetal de las marismas analizadas.El segundo gran objetivo de esta Tesis Doctoral consiste en analizar algunos aspectos que se desconocen de la biología, ecología y fisiología de Spartina densiflora. Para ello, se realizan tanto experimentos de campo como de laboratorio, que nos permiten profundizar en los mecanismos de invasión de esta especie en los estudios iniciales de su ciclo de vida, y se estudia su tolerancia a algunos de los factores ambientales más importantes de nuestras marismas, aún no analizados para esta especie. Los objetivos parciales que se plantean para su consecución son: 4. Estudiar la capacidad de germinación y reclutamiento de las plántulas de Spartina densiflora en respuesta al tipo de sustrato y l aposición fisiográfica en las marismas (frente a gradientes de salinidad, potencial redox, horas de inundación, contenido hídrico, etc) y el efecto de la presencia de vegetación vecina. 5. Analizar la tolerancia de Spartina densiflora a concentraciones elevadas de zinc, uno de los elementos traza con mayor representación en el sedimento contaminado de las marismas del estuario conjunto de los ríos Odiel y Tinto, y considerado esencial para las plantas.6. Estudiar la tolerancia de Spartina densiflora a la inundación prolongada y evaluar la viabilidad del empleo de inundaciones controladas como técnica de control o erradicación de este especie invasora en nuestros estuarios.El tercer objetivo de este Tesis Doctoral es el estudio de la eficacia del empleo de métodos químicos (herbicidas) para la lucha contra la invasión de Spartina densiflora en las marismas del Golfo de Cádiz. Para la consecución de este objetivo se realizan ensayos de dosis-respuesta de Spartina densiflora frente a la acción de dos herbicidas y se llevan a cabo estudios de absorción de los herbicidas en el suelo. Los objetivos parciales son:7. Determinar el efecto de diferentes dosis de glifosato e imazamox (herbicidas de tipo post-emergente) sobre el crecimiento y el aparato fotosintético de Spartina densiflora.8. Evaluar el impacto de estos herbicidas y sus compuestos primarios de degradación en el sistema suelo-agua en un ambiente tan particular como las marismas.Los objetivos establecidos en la presente Tesis Doctoral suponen un claro avance en el conocimiento de la ecofisiología de la especie, Spartina densiflora, y proporcionan herramientas y conocimientos claves para la correcta gestión de la principal especie invasora de las marismas del Golfo de Cádiz, confiriéndole un carácter aplicado. La elaboración de una cartografía de detalle que determine los límites y la extensión de la invasión constituye, además, una importante transferencia tecnológica para los organismos gestores.Premio Extraordinario de Doctorado U