The temperate seagrass species Cymodocea nodosa and the associated bacteria co-response to sunscreen pollution.

Sunscreens are included among the contaminants of emerging concern (CECs) as their production and use have spread over years while damaging aquatic biota. Sunscreens can damage the photosynthetic systems and change the microbiome of seagrasses, triggering alterations in carbon metabolism -including primary production and dissolved organic carbon (DOC) fluxes- and ecological functions. Here, we conducted a 31-day mesocosm experiment exposing Cymodocea nodosa plants to a mixture of commercial sunscreens.

Nutrient enrichment and herbivory alter carbon balance in temperate seagrass communities.

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.

Patch age alters seagrass response mechanisms to herbivory damage.

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.

Recent trend reversal for declining European seagrass meadows.

Seagrass meadows, key ecosystems supporting fisheries, carbon sequestration and coastal protection, are globally threatened. In Europe, loss and recovery of seagrasses are reported, but the changes in extent and density at the continental scale remain unclear. Here we collate assessments of changes from 1869 to 2016 and show that 1/3 of European seagrass area was lost due to disease, deteriorated water quality, and coastal development, with losses peaking in the 1970s and 1980s.

Global and local disturbances interact to modify seagrass palatability.

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.

Interaction between Ammonium Toxicity and Green Tide Development Over Seagrass Meadows: A Laboratory Study.

Eutrophication affects seagrasses negatively by increasing light attenuation through stimulation of biomass of fast-growing, bloom-forming algae and because high concentrations of ammonium in the water can be toxic to higher plants. We hypothesized nevertheless, that moderate amounts of nitrophilic macroalgae that coexists with seagrasses under eutrophic conditions, can alleviate the harmful effects of eutrophication on seagrasses by reducing ammonium concentrations in the seawater to non-toxic levels because such algae have a very large capacity to take up inorganic nutrients. We studied therefore how combinations of different ammonium concentrations (0, 25 and 50 μM) and different standing stocks of macroalgae (i.

Spatial variability and response to anthropogenic pressures of assemblages dominated by a habitat forming seaweed sensitive to pollution (northern coast of Alboran Sea).

The Cystoseira ericaefolia group is conformed by three species: C. tamariscifolia, C. mediterranea and C.

Application of the CARLIT index along a biogeographical gradient in the Alboran Sea (European Coast).

An index, based on littoral communities assemblages (CARLIT), was applied to assess the ecological status of Northwestern Mediterranean coastal waters, following the requirements of the European Water Framework Directive. The biogeographical particularities of the Alboran Sea suggested a reassessment of this index, and that was the main objective of this work. Due to these biogeographical particularities, two regions were proposed in the studied region, with new reference conditions for each region.

Multi-metric index based on the seagrass Zostera noltii (ZoNI) for ecological quality assessment of coastal and estuarine systems in SW Iberian Peninsula.

The aim of this study was to develop an ecological quality index based on the seagrass Zostera noltii (ZoNI) according to the WFD requirements. Eleven Z. noltii meadows of SW Iberian Peninsula under contrasting levels of anthropogenic disturbance were considered: 5 sites in Ria Formosa (Portugal), and 6 sites in Spain (Huelva and Cadiz).

GROWTH DYNAMICS OF ULVA ROTUNDATA (CHLOROPHYTA) IN A FISH FARM: IMPLICATIONS FOR BIOMITIGATION AT A LARGE SCALE(1).

Changes in biomass of several macroalgae [Ulva rotundata Bliding; Gracilariopsis longissima (S. G. Gmel.

Clonal extent, apical dominance and networking features in the phalanx angiosperm Hornem.

Disaggregating seagrass meadows and studying its components separately (clones, ramets, shoots) can provide us insights on meadow dynamics and growth patterns. The clonal growth, dependent upon clonal rules may regulate and impose constraints to plant architecture and, therefore, determine how individual clones evolve into the environment. In order to investigate the relationship between clonal growth rules and clone architecture, the belowground network architecture of single-clones of the seagrass was studied.

Evidence for a plasmalemma-based CO2 concentrating mechanism in Laminaria saccharina.

A kinetic analysis of the photosynthesis inhibition by buffers allowed quantification of some components of the carbon concentrating mechanism (CCM) of the brown macroalga Laminaria saccharina. The CCM was based on the presence of acid regions outside the plasma membrane that increased the CO(2) concentration available for photosynthesis by 10-20 times above that of the bulk medium at alkaline pH. Furthermore, the results suggested that the CCM is located mainly on the cell membrane and not in the chloroplast, as suggested for most macroalgae.

Fire, rain and the selection of seeder and resprouter life-histories in fire-recruiting, woody plants.

Several Cape species of the genus Erica are known to present seeder and resprouter phenotypes, and this variation seems to have a genetic basis. Therefore, this genus provides ideal model systems for using to elucidate the evolution of nonsprouting or seeder and resprouter life-histories in woody, fire-recruiting plants. A simple simulation model was developed to identify, under life-history optimality, the ecological conditions (viz.

Growth, carbon allocation and proteolytic activity in the seagrass Zostera noltii shaded by Ulva canopies.

The effects of light reduction [100%, 25%, 10% and 1% mean daily-integrated photon irradiance (I)] by Ulva rigida C. Agardh canopies on carbon balance, sugar-related enzymes and proteolytic activities of the seagrass Zostera noltii Hornem. were investigated.