Publications by authors named "Jimenez-Ramos R"

Ocean acidification (OA) and global warming (GW) drive a variety of responses in seagrasses that may modify their carbon metabolism, including the dissolved organic carbon (DOC) fluxes and the organic carbon stocks in upper sediments. In a 45-day full-factorial mesocosm experiment simulating forecasted CO and temperature increase in a Cymodocea nodosa community, we found that net community production (NCP) was higher under OA conditions, particularly when combined with warming (i.e.

View Article and Find Full Text PDF

Climate change and disease are two major threats to maintaining healthy seagrass habitats. Seagrasses, and the ecosystems they support, play a critical ecological role in global carbon (C) cycles, providing key ecosystem services, such as blue carbon storage. Zostera marina (eelgrass), the most widespread seagrass species globally, is increasingly affected by warming and is also regularly infected by the endophytic pathogen Labyrinthula zosterae.

View Article and Find Full Text PDF

Large nutrient levels and herbivory stress, particularly when acting together, drive a variety of responses in seagrass communities that ultimately may weaken their carbon balance. An in situ three-months experiment was carried out in two contrasting seasons to address the effects of two levels of nutrient load and three levels of artificial clipping on Cymodocea nodosa plants. Nutrient enrichment shifted the community from autotrophic to heterotrophic and reduced DOC fluxes in winter, whereas enhanced community carbon metabolism and DOC fluxes in summer.

View Article and Find Full Text PDF

Natural disturbances can produce a mosaic of seagrass patches of different ages, which may affect the response to herbivory. These pressures can have consequences for plant performance. To assess how seagrass patch age affects the response to herbivory, we simulated the effect of herbivory by clipping leaves of Halodule wrightii in patches of 2, 4 and 6 years.

View Article and Find Full Text PDF

The dissolved organic carbon (DOC) leached from two types of microplastics (polyethylene and polypropylene) frequently found in coastal areas were evaluated in situ. Subsequently, the bioavailability of leached DOC was assessed for microbial inocula from different coastal communities (i.e.

View Article and Find Full Text PDF

Seagrass communities have been degraded worldwide experiencing elevated shoot density reduction by anthropogenic chronic pressures. This study aims to assess how a chronic (i.e.

View Article and Find Full Text PDF

Coastal environments are usually composed by heterogeneous coastal-seascape, which can modify macroplastics accumulation dynamic. We evaluated seasonally the litter trapped on tidal-dominated habitats including two seagrass species, salt marsh, sandy beach, bare sediment and rocky bottom. Vegetated habitats showed the highest plastic accumulation in autumn-winter seasons, especially in medium-lower tidal-elevation zones.

View Article and Find Full Text PDF

Seagrass meadows are highly dynamic, particularly in sites where extreme climatological events may produce a mosaic of patches with different ages. This study evaluates the community carbon metabolism, dissolved organic carbon (DOC) fluxes and associated fauna in patches of Halodule wrightii with different ages since establishment. Net community production declined as patch age increased, probably due to the increase in non-photosynthetic tissues, higher respiration rates of the community assemblage and a likely increase in self-shading of the canopy.

View Article and Find Full Text PDF

Coastal development and climate change are sparking growing concern about the vulnerability of the organic carbon (OC) stocks in marine sediments to remineralization, especially in high threaten coastal ecosystems like seagrass meadows. Uncertainties still exist regarding the role played by hydrodynamics, seagrass canopies and sediment properties in OC resuspension and remineralization. A set of laboratory experiments were conducted to assess, for the first time, the mechanisms by which the particulate and dissolved organic carbon (POC and DOC) may be released and remineralized under hydrodynamic conditions (i.

View Article and Find Full Text PDF
Article Synopsis
  • The survival of benthic macrophyte communities, like seagrass and macroalgae, depends on their ability to balance photosynthesis and respiration during light stress.
  • The dissolved organic carbon (DOC) they release, mainly driven by light availability, is crucial for marine ecosystems and carbon storage in the ocean.
  • The study found that while light reduction decreased productivity in both communities, they showed resilience to unfavorable light conditions, particularly C. prolifera, which had better recovery capabilities.
View Article and Find Full Text PDF

Seagrass beds act as blue carbon sinks globally as they enhance the trapping of recalcitrant (i.e., low biodegradability) organic carbon in their sediments.

View Article and Find Full Text PDF

Cadiz Bay is a shallow mesotidal lagoon with extensive populations of the seagrass Cymodocea nodosa at intertidal and shallow subtidal elevations. This work aims to understand the mechanisms behind the resilience of this species to gradual sea level rise by studying its acclimation capacity to depth along the shallow littoral, and therefore, to gradual variations in the light environment. To address this objective, these populations have been monitored seasonally over a 10 year period, representing the longest seasonal database available in the literature for this species.

View Article and Find Full Text PDF

Nutrient enrichment can alter negatively benthic communities and reduce their ecological services. This study explores in two contrasting seasons (winter and summer), the effects of in situ nutrient enrichment at the community level on carbon metabolism and dissolved organic carbon (DOC) fluxes in two benthic communities dominated by the seagrass Cymodocea nodosa and by the macroalga Caulerpa prolifera. Under nutrient enrichment, C.

View Article and Find Full Text PDF

Seagrasses are key habitat-forming species of coastal areas. While previous research has demonstrated considerable small-scale variation in seagrass abundance and structure, studies teasing apart local from large-scale variation are scarce. We determined how different biogeographic scenarios, under varying environmental and genetic variation, explained variation in the abundance and structure (morphology and biomass allocation), epiphytes and sexual reproduction intensity of the seagrass Cymodocea nodosa.

View Article and Find Full Text PDF

Seagrasses form one of the most productive and threatened ecosystems worldwide because of global change and anthropogenic pressures. The frequency of extreme climatic events, such as heat waves, are expected to increase and may drive even more adverse effects than gradual warming. This study explores for the first time the effects of a sudden and temporary increase of temperature in situ on carbon metabolism and dissolved organic carbon (DOC) fluxes in a community dominated by a seagrass (Cymodocea nodosa) during two contrasting seasons (winter and summer).

View Article and Find Full Text PDF

Global change has been acknowledged as one of the main threats to the biosphere and its provision of ecosystem services, especially in marine ecosystems. Seagrasses play a critical ecological role in coastal ecosystems, but their responses to ocean acidification (OA) and climate change are not well understood. There have been previous studies focused on the effects of OA, but the outcome of interactions with co-factors predicted to alter during climate change still needs to be addressed.

View Article and Find Full Text PDF

Global change, such as warming and ocean acidification, and local anthropogenic disturbances, such as eutrophication, can have profound impacts on marine organisms. However, we are far from being able to predict the outcome of multiple interacting disturbances on seagrass communities. Herbivores are key in determining plant community structure and the transfer of energy up the food web.

View Article and Find Full Text PDF
Article Synopsis
  • Seagrass interacts with water currents, affecting the survival of species that feed on particles, like filter feeders.
  • An experiment revealed that the density and arrangement of seagrass impacts the amount of edible particles available, influenced by the presence of filter-feeding organisms like cockles.
  • The study suggests that areas with low seagrass density offer better protection and more resources for filter feeders, while dense patches concentrate resources within, impacting feeding efficiency.
View Article and Find Full Text PDF