Exploring the newly emerging effects of native seagrasses on survival and growth of non-native juvenile clams

The Manila clam (Ruditapes philippinarum) has been introduced into the Atlantic European coast for commercial exploitation. In this region, the population dynamics of this clam species may be determined by the interaction with the native dwarf eelgrass (Zostera noltei). We performed an experiment in the tidal flats of an estuary located in northern Spain to analyse the interaction between Z. noltei and juvenile Manila clams. Based on existing knowledge, it was hypothesised that seagrasses act as a nursery protecting juveniles from predation, which is an important cause of natural mortality, and that seagrass density influences the survival, growth and condition of clams. The results indicate that the effects of seagrasses on juvenile clams depends on shoot density, which mainly determine the relative prevalence of positive versus negative interactions. Dense seagrass meadows protect juvenile clams from predation, likely decreasing their visibility and reducing the efficiency of predators. However, in these dense meadows, a decline in the condition of clams was also observed, although not in shell growth. This decline can be due to the fact that food supply in dense meadows is slow and does not fulfil the replenishment rates required by filter-feeding organisms or because competition for space with the seagrass causes stress. Clams are larger in populations where predator access is prevented, possibly indicating selective predation on larger organisms when this interaction is allowed. The knowledge gained from this experiment is of great interest for analysing possible future trends in clam populations and the derived social implications given its high economic value.This research was part of the ECOTOPO project (RTI2018-096409-B-I00), financially supported by the Spanish Ministry of Science and Innovation through the National Plan for Scientific Research, and the project “Profundizando en el conocimiento de la Biodiversidad en estuarios: el efecto de la escala y la presión en los patrones biológicos funcionales” (56.VP76.64662), financially supported by the regional government through the Consejerı́a de Universidades, Igualdad, Cultura y Deporte del Gobierno de Cantabria (Convocatoria Financiada por el Contrato Programa Gobierno de Cantabria-UC). This study was also supported by the regional government through the Consejería de Desarrollo Rural, Ganadería, Pesca y Alimentación

Nested Socio-Ecological Maps as a Spatial Planning Instrument for Estuary Conservation and Ecosystem-Based Management

ABSTRACT: Estuaries are socio-ecological systems that can be represented as a holistic combination of biotic and abiotic conditions in spatially explicit units defined by: (i) the ecotope, as the integration of the physiotope (abiotic-homogeneous units) and the biotope (biotic-homogeneous units), and (ii) the anthrotope, synthesizing data on human drivers of ecological change. Nested physiotopes were identified in an estuary using a hierarchical approach that integrates information about eight abiotic, and biologically meaningful, variables. The biotope of Zostera noltei was delimited using a potential distribution model of species and overlapped with the physiotope map to characterize the ecotopes. The anthrotope was estimated as the cumulative impacts of anthropic activities over the ecotopes. The diversity of Z. noltei ecotopes was compared with the anthrotope map to estimate the potential impacts of human pressures on this species. The hierarchical methodology and resulting maps provide flexible and interdisciplinary tools for conservation, management, education and research.This research was part of the ECOTOPO project (RTI2018-096409-B-I00) financially supported by the Spanish Ministry of Science and Innovation through the National Plan for Scientific Research

Estrategias metodológicas para desarrollar iniciación a la escritura de los niños/niñas del primer año de educación general básica “Juan Francisco Cevallos” de la ciudad de Cotacachi en el año lectivo 2012-2013

Potencializar el desarrollo de la iniciación a la escritura a través de estrategias metodológicas, para fortalecer la motricidad fina de los niños/as del P.A.E.G.B. “Juan Francisco Cevallos” de la ciudad de Cotacachi.La presente investigación se llevó a cabo en el Primer Año de Educación General Básica “Juan Francisco Cevallos” de la Ciudad de Cotacachi, con la finalidad de identificar el proceso que utilizan las maestras para iniciar en la escritura con sus niños/as y de esta manera aportar con estrategias metodológicas que potencialicen esta enseñanza. La identificación de algunas causas y efectos hicieron que se opte por la formación de estrategias más lúdicas las cuales motiven al niña/o a entrar en el mundo mágico de la escritura, ya que esto le servirá para toda su vida. Para la Construcción del Marco Teórico se utilizó bibliografía especializada y actualizada, en libros, revistas, e internet referente a la iniciación a la escritura y motricidad fina, encontrando así la mejor manera de llamar la atención del niño/a. También se realizó el posicionamiento teórico personal en la que nos identificamos con la teoría Constructivista de Ausubel. Este proyecto de investigación es factible, ya que se basó en una investigación, de campo, exploratoria, descriptiva propositiva, para logra dar solución de manera creativa al problema planteado y cubrir una necesidad de los investigados/as. Los niños/as realizaron una encuesta de acuerdo a su edad, con la cual se pudo comprobar el nivel en que se encontraban con respecto a la iniciación a la escritura y motricidad fina. En la guía didáctica existe una serie de estrategias para que las maestras pongan en práctica en la enseñanza aprendizaje de la escritura, siendo esta materia la base fundamental para realizar futuros aprendizajes, dentro de su formación integral. Al respecto se puede manifestar que la principal meta de la Educación Básica es crear niños/as que sean capaces de expresar sus sentimientos y emociones por medio de la escritura, que sean creadores, descubridores, con mentalidad crítica frente a los diversos fenómenos de la vida

Characterization of Gelidium corneum's (Florideophyceae, Rhodophyta) vegetative propagation process under increasing levels of temperature and irradiance

Climate change is affecting Gelidium corneum (Hudson) J.V. Lamouroux fields in the Bay of Biscay by reducing its cover and biomass. Understanding those changes requires a good characterization of the responses of this species to different stressors, particularly the effects on key processes such as the vegetative propagation. Here, we aimed to characterize the interactive effect of temperature (15, 20 and 25◦C) and irradiance (5-10, 55-60 and 95-100 μmol*m2*s- 1) on two phases of the vegetative propagation process: the re-attachment capacity and the survival of re-attached fragments. The study findings revealed significant effects of both temperature and irradiance in the re-attachment capacity of the species, with higher rates of attachment registered at 20 ◦C and 5-10 μmol*m- 2*s-1 after 10, 20 and 30 days of culture. However, the interaction effects were not significant at any time interval. At higher or lower temperatures and increasing irradiances, the attachment capacity was reduced. On the other hand, irradiance was demonstrated to be the main factor controlling the survival of rhizoids. In fact, higher levels of irradiance generated severe damage on rhizoids, and thus, conditioned the development of new plants. According to this, it seems clear that the vegetative propagation process of this species is expected to become more vulnerable as both variables are expected to rise due to climate change. An increased vulnerability of this species may have several implications from an ecological and economic perspective, so we encourage to continue exploring the factors and processes controlling its distribution in order to adopt better management actions in the future.This work was funded by the National Plan for Research in Science and Technological Innovation from the Spanish Government 2017–2020 [grant number C3N-pro project PID2019-105503RB-I00] and co-funded by the European Regional Development’s funds. Samuel Sainz-Villegas and Begoña Sánchez-Astráin acknowledge the financial support received under predoctoral grants from the Spanish Ministry of Science, Innovation and Universities [grant numbers: FPU18/03573 and PRE2020-096255, respectively]. This work is part of the PhD project of Samuel Sainz-Villegas

Assessment of ecosystem services of an urbanized tropical estuary with a focus on habitats and scenarios

Tropical estuaries are one of the most valuable ecosystems on the planet because of the number of ecosystem services they provide. The increasing anthropogenic pressure to which these estuaries are subject has caused a reduction in their natural capital stock. Therefore, the application of a pragmatic and rational ecosystem-based management approach to sustainably manage the multiple ecosystem services provided by this ecosystem is necessary. The aim of our study is to present an approach that combines prospective scenarios with habitat-based perspective to assess the supply capacity of ecosystem services, plus determine the impact of protected areas in an urbanized tropical estuary. The current situation and two scenarios were generated to evaluate the capacity of habitats to supply ecosystem services. This type of assessment will allow the decision makers to visualize the effect of their choices or the occurrence of events which might produce significant changes in the estuary. Thus, over time, measures can be taken to sustain the supply of ecosystem services. We determined that the establishment of protected areas have a positive impact; however, the effect is not the same for all of them. Consequently, indicating that actions such as community participation, research, education, management planning and infrastructure development must accompany the development of a protected area

The Use of Hydrodynamic Models in the Determination of the Chart Datum Shape in a Tropical Estuary

Estuaries are transitional environments with ideal conditions for port construction and navigation. They represent a challenge to hydrographic services due to the dynamics of the seabed and the tidal wave deformation. The bottom slope, the convergence of the channels, and the nonlinear efects produced by the bottom friction produce variation in both the tidal range and the location of the chart datum (CD). In this study, sea level data series obtained from the nodes of the mesh of a hydrodynamic model (virtual tide gauges) were used to calculate the harmonic constituents, form factor, asymmetry, and estuary type. The final chart datum surface, obtained from the hydrodynamic model, was used to determine the separation values between zones and also the number of tidal zones in an estuarine system. It was found that in a complex hydrodynamics scenario, the use of the ellipsoidal referenced surveying (ERS) method is more convenient than traditional tidal zoning survey. In the ERS method, once the CD model is complete, it must be attached to the ellipsoid directly. Finally, the variation of the CD in di erent scenarios (due to anthropogenic action) was assessed

Distribution patterns of the gooseneck barnacle (Pollicipes Pollicipes [GMELINn, 1789]) in the Cantabria region (N Spain): exploring different population assessment methods

The gooseneck barnacle Pollicipes pollicipes is a very valuable marine resource on the coasts of Spain and Portugal. To maintain the sustainable exploitation of this species, periodical large-scale population assessments are essential. Because of the heterogeneous distribution of these populations in aggregates, together with the difficulties associated with sampling (i.e., access to rocky reefs, wave exposure, high tides, etc.), there is a lack of studies in this regard. In light of these constraints, the coverage, biomass, and available stock of gooseneck barnacle were first estimated using a novel semiquantitative method along a 215-km long coast at 10 fishing zones and three tidal levels. This study contributed to the first assessment of the distribution variability of gooseneck barnacle in the Cantabria region (N Spain), as the first step toward a long-term monitoring goal. The proposed method is based on a general coverage (GC) estimation, by means of (1) quantitative coverage measurements on quadrats (50 cm350 cm) located along vertical transects covering the intertidal bandwidth and corrected by tidal level bandwidths, (2) semiquantitative coverage estimates in larger areas, including 5 m on either side of the quadrats along the transect. Biomass samples were collected at each sampling point by scraping the 50 cm350 cm quadrat and fresh weight of the samples was measured. This method arrives at the biomass estimates by means of a power regression model for the coverage?biomass relationship. The population distribution pattern along the coast was also explored separately, by commonly used (1) quantitative coverage estimates in quadrats with no bandwidth correction (sample coverage, SC) and (2) semiquantitative estimates, as in the proposed method (transect coverage, TC), both of which included biomass sampling. Biomass and standing stocks values obtained using GC were lower and consumed less sampling time than those obtained by TC, and particularly SC. The results suggest that the proposed method might be suitable for the assessment of P. pollicipes populations in large coastal areas, as it potentially avoids stock overestimation by detecting the spatial distribution heterogeneity and reduces the sampling time.The main Directorate of Fisheries of Cantabria (DFC) funded this work. We wish to thank DFC technicians, fishery guards and shell-fishermen for the specific support during the fieldwork, and the colleagues from DFC, who helped us in the laboratory works

Coastal engineering infrastructure impacts Blue Carbon habitats distribution and ecosystem functions

ABSTRACT: Intertidal estuarine habitats (e.g., saltmarshes and tidal flats) provide important ecosystem services to society, including coastal protection, food provision and Corg sequestration. Yet, estuaries and estuarine habitats have been subjected to intense human pressure, such as land-use change and artificialization of the shoreline to support economic activities and uses. Construction of engineering infrastructures (e.g., piers, bridges) in these areas alters estuary-wide hydromorphological conditions and thus sedimentation patterns at the estuarine scale, which are key drivers of habitats distribution and ecosystem structure, processes and functions. Most of the research on the impact of civil engineering structures on coastal habitats has focused on the biological communities that colonize them or the bottoms where they are placed, whereas their indirect impacts on adjacent habitats has been largely unexplored. Understanding the influence of man-made infrastructures on the distribution of estuarine habitats and functions is critical, particularly considering that shoreline armoring is expected to increase as a way to protect coastal areas from hazards derived from climate change. Shifts in habitat distribution and functions occur in several years or decades and relating them with the occurrence of past historical events is challenging when no monitoring data is available. By examining historical aerial photographs and different biogeochemical properties along a saltmarsh soil record, this study demonstrates that the construction of an infrastructure (i.e. bridge) caused a rapid transformation (~30 years) of a bare sandflat into a high marsh community and to significant changes in sediment biogeochemical properties, including the decrease in sediment accretion rate and Corg burial rates since then. This study contributes to increase the knowledge on the impact that the construction in coastal areas of civil engineering infrastructures can cause in intertidal habitats distribution and the ecological functions they provide for climate change adaption and mitigation.This research was carried out with the contribution of the LIFE Programme of the European Union to the Project ADAPTA BLUES (ref. LIFE18 CCA/ES/001160). This document reflects only the author’s view and the Agency/ Commission is not responsible for any use that may be made of the information it contains. Authors acknowledges the financial support from the Government of Cantabria through the Fénix Programme. The authors want to thank the support of the Generalitat de Catalunya to MERS (2017 SGR-1588) and the Spanish Government for the “Maria de Maeztu” program for Units of Excellence to ICTA (Grant No. CEX2019-000940-M). We would like to thank Joan Manel Bruach Menchen from the Grup de Recerca en Radioactivitat Ambiental de Barcelona—GRAB (Universitat Autònoma de Barcelona) for his work on the analysis of 210Pb dating. In memorial of Jordi Garcia-Orellana, who left us during the preparation of this manuscript, but whose ideas, motivation and help always made this job easy and fun

Exploring the effects of temperature and light availability on the vegetative propagation processes of the non-native species Asparagopsis armata

Widespread generalist species, particularly the non-native invasive ones, are expected to be enhanced by climate change resulting in a biotic homogenization of ecosystems. The red seaweed Asparagopsis armata is a non-native opportunistic species, widely distributed in the European coasts of the North Atlantic, where it has been considered invasive. In this work, we examined the effects of temperature and irradiance on the vegetative propagation process of this species in a laboratory experiment. We considered vegetative propagation due to its implications in the invasion process (as it is considered one of the main sources of recruitment). In gametophytes, the process was characterized through the survival rates of hook-shaped specialized structures and the production and growth of new plantlets from hooks of 1-3cm in length. In tetrasporophytes, the growth and phycobiliprotein contents of previously excised tufts was analyzed. For gametophytes, results revealed how vegetative propagation for this species was conditioned by the low survival rates of hooks once detached from the main thallus. In our experiment, survival probabilities after 30 days of culture were always below 50%. Comparisons among environmental conditions showed lower survival rates under increasing levels of temperature and decreasing levels of irradiance. In fact, mass mortality was detected at 18°C and low irradiance, where almost any hook-shaped fragment survived. Nevertheless, patterns of appearance and growth of plantlets at different temperatures and irradiances were not clear. In the case of tetrasporophytes, only positive growth rates were registered at 15°C and 55-60 mmol/m2/s after 30 days of culture. Higher concentration of phycobiliproteins was detected at higher temperatures during the first days of culture, while not clear patterns were detected at the end. In the light of climate change, understanding these reproduction patterns is necessary in order to adopt better management actions in the future.The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was funded by the National Plan for Research in Science and Technological Innovation from the Spanish Government 2017-2020 [grant number C3N-pro project PID2019-105503RB-I00] and co-funded by the European Regional Development’s funds. Samuel Sainz-Villegas and Begoña Sánchez-Astráin acknowledge the financial support received under predoctoral grants from the Spanish Ministry of Science, Innovation and Universities [grant numbers: FPU18/03573 and PRE2020-096255, respectively]. This work is part of the PhD project of Samuel Sainz-Villegas

Environmental risk assessment of dredging processes-application to Marin harbour (NW Spain)

ABSTRACT. A methodological procedure to estimate the environmental risk of dredging operations in aquatic systems has been developed. Environmental risk estimations are based on numerical models results, which provide an appropriated spatio-temporal framework analysis to guarantee an effective decision-making process. The methodological procedure has been applied on a real dredging operation in the port of Marin (NW Spain). Results from Marin harbour confirmed the suitability of the developed methodology and the conceptual approaches as a comprehensive and practical management tool.The authors would like to thank the Marin Port Authority for the provided data. Part of this study has been sponsored by the INNPACTO programme (2008–2011) of the Spanish Ministry of Science and Innovation (IPT-310000-2100-17)