Pattern formation in a predator-prey system characterized by a spatial scale of interaction

We describe pattern formation in ecological systems using a version of the classical Lotka-Volterra model characterized by a spatial scale which controls the predator-prey interaction range. Analytical and simulational results show that patterns can emerge in some regions of the parameters space where the instability is driven by the range of the interaction. The individual-based implementation captures realistic ecological features. In fact, spatial structures emerge in an erratic oscillatory regime which can contemplate predators' extinction.Comment: 5 pages, 4 figure

Spatial isolation impacts pollinator visitation and reproductive success of a threatened self-incompatible Mediterranean tree

Pollination service is crucial to achieve successful plant sexual reproduction and long-term population persistence. This pollination service can be affected by plant conspecific density and also by intrinsic features of individuals related to their flowering phenology and floral display. However, studies examining intrinsic and extrinsic traits on pollinator visitation and reproductive success of Mediterranean trees with limited reproduction are still scarce. We analyzed the effects of plant isolation, flowering phenology, flower weight and tree size on flower visitation probability, flowering patch visitation probability, fruit set and crop size. To this end, we intensively monitored pollinator visitation and fruit production of 67 (in 2019) and 73 (in 2020) Pyrus bourgaeana Decne trees within a threatened Mediterranean population. Our results revealed that isolated individuals received more pollinators than those on conspecific aggregations, suggesting intraspecific competition for pollinators in dense flowering neighborhoods. However, fruit set was higher in trees close to flowering conspecifics despite having fewer visits from pollinators, suggesting pollen limitation but not pollinator limitation in spatially isolated trees. Interestingly, we found increased crop sizes in spatially isolated trees which could be related to reduced intraspecific competition for resources in low-density neighborhoods (water, nutrients) and/or to higher reproductive investment (i.e. higher flower production). Overall, our results indicated pollen but not pollinator limitation in spatially isolated trees. Under this scenario of sexual reproduction mediated by pollinators, our findings stress the relevance of individuals’ spatial distribution for self-incompatible trees exhibiting low individuals’ densitiesinfo:eu-repo/semantics/publishedVersio

Green supported liquid membranes: The permeability activity-based linear operation (PABLO) method

Supported liquid membranes (SLMs) containing novel green solvents are proposed as a sustainable alternative separation process in the recovery of biomolecules. In this work, succinic acid has been successfully extracted from model fermentation broths through a stripping phase-facilitated transport mechanism with four different green supported liquid membranes: two eutectic solvents (DL-menthol:OctA and N4444Cl:OctA), the bio-based solvent eucalyptol and the ionic liquid C4pyrr]Tf2N]. A permeability activity-based model that takes into account for the first time solute-phase affinities has been developed using the quantum chemical COSMO-RS method; the model corrects the mass transfer driving force and allows extraction predictions beyond the concentration equilibrium. The best recovery has been achieved experimentally for the eucalyptol-based SLM (concentration factor of 1.4) using an alkaline aqueous solution (0.5 M NaOH) as the stripping phase. A countercurrent cascade extraction process design is proposed, and a graphical method to determine the stage number, interstage concentrations as well as mass transfer area requirements is presented. This new tool, the Permeability Activity-Based Linear Operation (PABLO) method, will substantially enhance the process design of SLMs technology for the biorefinery industry

Appearance of pyrophyllite as replacements of spiriferids (Brachiopoda) Shells of the devonian in the Central-Iberian zone (Hesperic Massif, Spain).

[Abstract] Amacroscopic pyrophyllite bearing mineralization related to shells ofspiriferids has beeen found in the Herrera Formation (southern Central-Iberian Zone, Hesperic Massif, Spain). The observed mineral asociation is pyrophyllite + nacrite + quartz + calcite + anhydrite, and it is interpreted as resulting from the substitution ofinitial carbonatic shell by a Si, Al, S rich hydrothermal solutio