Martínez, M.L.; Taramelli, A., and Silva, R., 2017. Resistance and resilience: Facing the multidimensional challenges in coastal areas. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 1–6. Coconut Creek (Florida), ISSN 0749-0208.

Coastal ecosystems are subject to recurrent natural disturbances that act as drivers of ecosystem dynamics. In addition, in recent years, human impact has exerted intense pressures on these ecosystems, altering the dynamics and reducing resistance and resilience. The former refers to the ability of a system to hold a force without any modification, while the latter is a measure of its the capacity to respond to the consequences of perturbation and return to its original status. How can we achieve coastal management actions so that coastal resistance and resilience are enhanced? This volume integrates a broad set of studies that analyse coastal resistance and resilience from different viewpoints, that include contrasting viewpoints that cover the natural environment (abiotic and biotic); social governance and networks; social dynamics; built infrastructure and a combination of the four. Indeed, a proper diagnosis of the status of the coast is required and adequate coastal management is necessary, so that risks to the population and environmental problems are minimized. Coastal managers, ecologists, engineers, decision makers and society in general are jointly responsible for the future of our dynamic coasts.

Chávez Cárdenas, X. and Kobayashi, N., 2017. Movement of wooden blocks on ground and pilings in swash zone. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 7–18. Coconut Creek (Florida), ISSN 0749-0208.

Time-varying interactions among storm surge, waves, sand beaches, and wooden houses determine the degree of damage to the houses on low-laying beaches but the complicated damage process is not well understood. An exploratory laboratory experiment consisting of eight tests was conducted in a wave flume with a sand beach to examine the movement of ten wooden blocks (idealized houses) on the foreshore and berm as well as on short and long pilings. The still water level was varied to create accretional and erosional profile changes on the foreshore and berm. The cross-shore wave transformation on the beach and the wave overtopping and overwash of the berm were measured in 71 runs of 400-s each. The initial block elevation above the sand surface is shown to have little effect on the hydrodynamics, sediment transport, and profile evolution in this experiment with widely-spaced blocks. The block floating and sliding on the sand surface and block falling from the pilings depended on the swash hydrodynamics and block clearance above the foreshore and berm whose profile varied during each test. A probabilistic model is developed to estimate the wetting, sliding, and floating probabilities for the block in the swash zone using the water depth measured in the vicinity of the block. The estimated probabilities are used to explain the observed block floating and falling.

Mendoza, E.; Odériz, I.; Martínez, M.L., and Silva, R., 2017. Measurements and modelling of small scale processes of vegetation preventing dune erosion. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 19–27. Coconut Creek (Florida), ISSN 0749-0208.

Traditionally, actions taken to reduce vulnerability to beach erosion have been based on protecting economic resources, recreational activities and human lives. Hard infrastructure for coastal protection has proven effective, but the side effects have been called into question, given that making the coastal system more rigid alters the natural dynamics, degrades environmental services and damages the landscape. Ecosystem based coastal defence strategies are now seen as a more environmentally friendly alternative which can maintain and even increase the resilience and resistance of coastal zones. This work aims to improve the understanding of the behaviour of nature-based coastal defences by analysing the morphodynamic response of a dune-beach system with vegetation to storms. Small scale tests were performed in which beach profiles with natural dune vegetation were exposed to high energy waves. Free surface elevation and velocity profiles were recorded during the tests and the profile evolution was measured at the end of each experiment. Erosion regimes of collision and overwash were observed in the dune profiles with a berm, whereas swash and overwash regimes were observed when no berm was present. Retarding erosion time seems to be the most relevant morphological effect of the dune vegetation, which gives a slight, but relevant, contribution to the resilience and resistance of the beach profile. In turn, the wave breaking point is displaced seawards and bed velocities close to the shoreline are lower when vegetation is present, both of which explain the protective role of vegetation on the beach profile. To develop a numerical tool capable of reproducing the morphological evolution of the beach profiles tested, the CSHORE model was calibrated and validated for the laboratory data finding good correlation.

López-Portillo, J.; Lara-Domínguez, A.L.; Vázquez, G., and Aké-Castillo, J.A., 2017. Water quality and mangrove-derived tannins in four coastal lagoons from the Gulf of Mexico with variable hydrological dynamics In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 28–38. Coconut Creek (Florida), ISSN 0749-0208.

This study explored the spatial variability of physico-chemical water variables (i.e., salinity, nitrogen, phosphorus and tannins) in contrasting seasons in four coastal lagoons (Chica y Grande, La Mancha, Sontecomapan and El Ostión) along Veracruz state, Mexico. We also calculated the mangrove and central basin water areas and associated them to physico-chemical data to analyze them by means of Principal Component Analysis (PCA) due to high correlation among variables. Finally, we elaborated coded maps of each lagoon to represent the gradients of the variables with statistically significant loadings in either of the first two components accounting for 50 to 70% of total data variability. In La Mancha, NH₄, NO₃ and RP but not salinity were associated with river outflows. In Grande and Chica, NH₄, NO₃ and RP were higher near the lagoon inlet, but the major river outflows was also in that area, confounding their actual source. Finally, NO₃ were strongly associated with river outflows in Sontecomapan and El Ostión. However, the concentrations of tannins were directly associated with mangrove cover in the four lagoons. Our results indicate that the connection with the sea, the position of the inflowing rivers, and the morphology of the lagoon provides the “estuarine signature” of each lagoon.

de la Lanza-Espino, G.; Silva, R.; Hernández-Pulido, S.; Mariño-Tapia, I., and Enríquez, C., 2017. A retrospective analysis of water quality in an open bay on the Mexican Pacific. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue, No. 77, pp. 39–50. Coconut Creek (Florida), ISSN 0749-0208.

Lack of knowledge about the complex interactions between the dynamics of natural systems (physical, chemical and biological) and the need for the resources found in coastal environments has led to the unplanned and disorganized development of several anthropogenic activities in the study area. It is important to revert this tendency and promote medium term studies that can help to foresee the unwanted effects, sometimes irreversible, of human activities on the environment. This paper includes results from hydrodynamic and water quality studies carried out in Petacalco Bay, Guerrero (Mexican Pacific) in order to present elements for future appropriate management of industrial outflows in the region. Around this bay there are important rivers and small villages, a major port, chemical and thermoelectric plants, all discharging their (generally untreated) effluents directly into the sea. The results of this study show that the overall water quality is similar to natural concentrations found in the ocean. Nevertheless, eutrophization was found, associated with the fertilizer industry, and the hot water discharge from the thermoelectric plant generates hot plumes, which dissipate in the environment, despite the intense and variable hydrodynamic characteristics of the region.

Chávez, V.; Mendoza, E.; Ramírez, E., and Silva, R., 2017. Impact of inlet management on the resilience of a coastal lagoon: La Mancha, Veracruz, Mexico. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 51–61. Coconut Creek (Florida), ISSN 0749-0208.

The importance of conserving wetlands for their functions and services, has shown the need for adequate management practices, which take into consideration the vulnerability and resilience of these ecosystems. The lagoon of La Mancha, Veracruz, Mexico, is a Ramsar site, which in practice is empirically managed by local fishermen. To assess the vulnerability of this ecosystem, the erosion/accretion of the beach, inlet dynamics, the hydrodynamics of circulation patterns in the lagoon during winter storms, and the effects of anthropogenic activities were studied. Four topographic surveys were performed between 2013 and 2015. Complementarily, physicochemical parameters in the lagoon and at the inlet were registered in November 2014.The field data shows that the beach is resilient to the effects of winter storms, as long as sediment availability is not interrupted. The circulation patterns of the lagoon were obtained using a 2D non linear shallow water numerical model; the results indicate that the winds and waves can induce the opening and closing of the inlet. The governing force in the lagoon hydrodynamics is the tidal oscillation, as corroborated by the physicochemical parameters measured. The natural cycles of the system are altered by the local fishermen, who once or twice a year open the inlet of the lagoon. It was found that the environmental resilience of the estuarine-lagoon system is quite sensitive to the number of times and the season when the inlet is opened and that the anthropogenic interference is increasing the vulnerability of the ecosystem of La Mancha.

Taramelli, A.; Valentini, E.; Cornacchia, L., and Bozzeda, F., 2017. A hybrid power law approach for spatial and temporal pattern analysis of salt marsh evolution. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 62–72. Coconut Creek (Florida), ISSN 0749-0208.

A striking feature in salt marshes is vegetation distribution, which can self-organize in patterns over time and space. Self-organized patchiness of vegetation can often give rise to power law relationships in the frequency distribution of vegetation patch sizes. In cases where the whole distribution does not follow a power law, the variance of scale in its tail may often be disregarded. The deviation from power laws represents stochastic effect that can be hybridized on the basis of a Fuzzy Bayesian (FB) generative algorithm, to emphasize the influence of different physical and climatic variables on the patch size distribution to detect tipping point of the ephemeral life of a salt marsh under frequent disturbance events. Using remote sensing observations, we investigate the statistical distribution of spatial vegetation patterns controlled by changes in environmental variables acting on salt marshes, and we speculate the conditions under which a shift from a scale-invariant (power law) distribution to patterns characterized by a dominant patch size could be expected using channel sinuosity as a parameter. Our results show that the hybrid model without considering channel sinuosity can only detect the pure power law exponent, while considering channel sinuosity detects the exponent in the tail of the patch size distribution. Thus the evolution of vegetation patches (under power law) detected by the hybrid model considering channel sinuosity can then be used to forecast potential deviation from steady states in intertidal systems, taking into account the climatic and hydrological regimes. The research shows how numerical thresholds can describe the influence of changes in the non-linearity of patch size frequency distribution and how these thresholds can be reflected as attributes for the resilience capacity measurements in estuarine salt marshes.

Cappucci, S.; Valentini, E.; Del Monte, M.; Paci, M.; Filipponi, F., and Taramelli, A., 2017. Detection of natural and anthropic features on small islands. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 73–87. Coconut Creek (Florida), ISSN 0749-0208.

Mapping the distribution of seabed habitats, and estimating the spatial distribution of features and biocenosis over land and the seafloor, is particularly important for the analysis of human impacts. The present paper uses an innovative image analysis method that integrates different data sources from airborne remote sensing and in situ measurements for different features, allowing the detection of ecological ‘tipping points’ both in emerged and submerged coastal environments. Results show that it is possible to differentiate between the respective roles of: first, the internal variability of the natural morphological system and second, of external forcing factors. The final evidence, however, identifies a clear signature of external forcing, but whether of anthropogenic or natural origin, is unclear. The spatial pattern of the response to anthropogenic forcing may be indistinguishable from patterns of natural variability. It is argued that this novel approach to define tipping points following anthropogenic impacts could be most valuable in the management of natural resources and the economic development of coastal areas worldwide.

Huff, T.P. and Feagin, R.A., 2017. Hydrological barrier as a cause of salt marsh loss. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 88–96. Coconut Creek (Florida), ISSN 0749-0208.

The Magic Ridge Marsh located along Magnolia Beach, Texas has rapidly degraded over the last few decades. This marsh is of great importance to wildlife and dependent recreational pursuits such as bird watching at the Magic Ridge Sanctuary and fishing in the marshes and adjacent bay. In this study, we decided to focus on the shell debris pile as aerial imagery, along with local knowledge, indicated that this was the point of hydrologic disturbance. In order to restore this ecosystem, the alterations to the hydrology had to be understood and thus the multi-stage approach was chosen to single out the environmental factors that influence the marsh. Land cover analyses were conducted in conjunction with analyses of precipitation and sea level rise data beginning in 1958 and ending in 2012. Tide and salinity data from March 2013 to August 2013 were obtained to determine tidal connectivity and salinity conditions within the marsh and bay. These data sets indicated that low marsh area decreased independently of sea level rise or precipitation. However, the tidal data showed the marsh was disconnected for extended periods of time resulting in increased salinity within the marsh. The lack of tidal exchange indicated that a blockage to tidal infiltration existed. However, during the period from 1958 to 2012, no new construction or man-made alteration to the inlets of the marsh occurred. This indicated that a separate entity was responsible for the impoundment, which would be a plug of sediment and shell that had accumulated in the Magnolia Inlet.

Huff, T.P. and Feagin, R.A., 2017. Restoring tidal equilibrium: Removing a hydrologic barrier and lowering salinity at the Magnolia Inlet, Texas. In: Martínez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 97–103. Coconut Creek (Florida), ISSN 0749-0208.

A large area of salt marsh located between Magnolia Beach and Indianola, Texas had rapidly degraded over the last few decades due to a hydrologic barrier. Sediment and shell debris in the main tidal channel had greatly reduced flow between interior sections of marsh and the adjacent open bay, blocking all hydrologic exchange except for extreme tides. As a result, the impounded waters were often hypersaline, the vegetation was dying, and access to habitat was restricted for aquatic nekton. Our overall objective was to identify the cross section of debris that would need to be removed from the channel in order to restore hydrologic flow. Using numerical modelling, the first goal was to identify the cross-section of the channel that would allow equilibrium with the potential tidal prism of the impounded water basin. Using a STELLA modelling approach, the second goal was to identify the length of time that it would take to restore normal salinity levels. Based on both these models and observed historical trends, a removal option of 13.5 m² inlet cross-section was selected, such that maximum water velocities (~0.8 m/sec) were predicted to reduce the probability that the channel would revert back to a blocked state and that salinities would equilibrate in less than 12 days. Approximately 780 m³ of shell and mud debris was removed, and field-measurements of both tidal flow and salinity generally verified the modelled predictions. Afterwards, the community began recovering with vegetation colonizing previously flooded areas and fish accessing the marsh as the barrier no longer blocked fish movement.

Moreno-Casasola, P.; Hernández, M.E., and Campos C., A., 2017. Hydrology, soil carbon sequestration and water retention along a coastal wetland gradient in the Alvarado Lagoon System, Veracruz, Mexico. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 104–115. Coconut Creek (Florida), ISSN 0749-0208.

The Alvarado Lagoon System (ALS) is a wetland complex in the Gulf of Mexico, with different types of wetlands. We studied six wetland types that differ in species composition and dominant life forms: Rhizophora-Avicennia mangrove, Pachira aquatica freshwater forested wetland, Sabal mexicana flooded palm forest, two broad-leaved marshes (Pontederia sagittata marsh in Rio Blanco; Pithecellobium-Spartina marsh in Popoyeca) and a cattail (Typha domingensis) marsh. The hydroperiod data indicate that all wetland types are flooded for several months of the year, the palm forest having the longest period of time without inundation. Significantly higher (p≤0.05) carbon stocks at a depth of 1 m and soil water storage were recorded for the forested wetlands (60 ± 6 kg C m⁻², 889 L m⁻³ respectively) and P. sagittata broad-leaved marshes (67 ± 9 kg C m⁻², 882 L m⁻³). The lowest values were recorded for the flooded palm forest (16 ± 5 kg C m⁻², 533 L m⁻³) and the mangrove (16 ± 2 kg C m⁻², 463 L m⁻³). This makes the ALS an important provider of ecosystem services, most notably via its freshwater forested wetlands and marshes. Draining these wetlands for agricultural purposes could lead to differing degrees of change in the soil's hydraulic characteristics, such as a decrease in its capacity to retain water and the loss of organic matter, and therefore a reduced capacity for carbon storage.

Lithgow, D.; Martínez, M.L.; Silva, R.; Geneletti, D.; Gallego-Fernández, J.B.; Cerdán, C.R.; Mendoza, E., and Jermain, A., 2017. Ecosystem services to enhance coastal resilience in Mexico: The gap between the perceptions of decision-makers and academics. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 116–126. Coconut Creek (Florida), ISSN 0749-0208.

In this study, we assessed the respective perceptions of academics and decision-makers concerning the relationships (dependence and impact) between economic activities and ecosystem services in coastal environments. Our goal was to explore the potential for achieving informed decisions that are based on an effective and appropriate use of the concept of ecosystem services. A set of questionnaires was e-mailed to a selected group of academics and decision-makers and the responses analysed. The perceived degree of negative impact caused by economic productive activities on ecosystem services differed, probably because of the different parameters used by each group: biophysical by academics and socioeconomic by decision makers. The academics commonly perceived that the negative impact and dependence of economic activities upon ecosystem services was much greater than that perceived by the decision-makers. This may indicate that decision-makers underestimate the impact of economic activities on ecosystem services during the decision-making process, or conversely, that academics potentially overestimate the impact. This dynamic could account for current discrepancies in the inadequacy of public policies related to resource management. Such differences of opinion, whether scientifically based or not, affect the decisions that are made and the conservation status of natural ecosystems, the ecosystem services they provide and their resilience to extreme disturbance events.

Vanderlinden, J.-P.; Baztan, J.; Touili, N.; Kane, I.O.; Rulleau, B.; Diaz Simal, P.; Pietrantoni, L.; Prati, G., and Zagonari, F., 2017. Coastal flooding, uncertainty and climate change: Science as a solution to (mis) perceptions? A qualitative enquiry in three coastal European settings. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 127–133. Coconut Creek (Florida), ISSN 0749-0208.

This paper contributes to the understanding of the interface between risk perception and climate change risk mitigation in coastal areas. In particular, we analyse the role of science-based knowledge and the so called “knowledge gap” in coastal stakeholders' verbalized perceptions of coastal risk. We use a qualitative approach to analyse of a corpus of 29 interviews conducted in three coastal European settings: Santander Bay (Spain), the Gironde Estuary (France), and Cesenatico (Italy). This analysis of stakeholders' perceptions of flood risk shows: (i) the science-based understanding of flooding as a probabilistic process is not always present and has little impact on the stated perceptions; and (ii) stakeholders and society as a whole frame risk mostly through values and norms. Given these findings, an increase in science-based knowledge within the world of coastal risk governance under climate change would contribute to safer coasts, provided that the production of science-based knowledge takes into account stakeholder values through a proactive dialogue with stakeholders.

Langle-Flores, A.; Ocelík, P., and Pérez-Maqueo, O., 2017. The role of social networks in the sustainability transformation of Cabo Pulmo: A multiplex perspective. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 134–142. Coconut Creek (Florida), ISSN 0749-0208.

Coastal tourism is often caught in a crossfire between economic benefits, ecological impacts and social tensions. Development of large-scale resorts can reduce the provision of certain ecosystem services and threat local people's livelihoods. Social networks might influence the transitions of governance systems into new adaptive models. We focus on the role of multiplex networks in the process of sustainability transformation by examining social networks that protected a marine reserve against the construction of a large scale development. The multiplex network exhibited a structure with five blocks: “scale-crossing brokers”, “visible leaders”, “ecosystem managers”, “visionaries” and “public sector”. This last block was structurally isolated from the rest of organizations. Multiplex networks facilitated the coordinated mobilization of information and resources across spatial scales. “Scale-crossing brokers” with the aid of “visible leaders” propelled up the local conflict toward national and global arenas, affecting the decision of Mexico's federal government to annul large scale resort's construction. Understanding the social processes that enable adaptive governance systems is crucial for sustainability transformations and resilience of coastal ecosystems.

Martínez, M.L.; Silva, R.; Lithgow, D.; Mendoza, E; Flores, P.; Martínez, R., and Cruz, C., 2017. Human impact on coastal resilience along the coast of Veracruz, Mexico. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 143–153. Coconut Creek (Florida), ISSN 0749-0208.

Coastal ecosystems are naturally exposed to recurrent disturbances, which act as drivers of ecosystem dynamics, but in recent years, human impact has exerted intense pressures, resulting in altered dynamics and thus, reduced resilience. In this work the state of Veracruz, on the Gulf of Mexico, was used as a case study to assess the impact of human activities and explore how these have affected coastal resilience. A regional diagnosis was performed, considering coastal morphology, sediment characteristics, shoreline dynamics, natural, and transformed ecosystems, conservation areas, and built infrastructure. The various causes of the chronic erosion taking place in the area are: subduction, rising sea levels, a fall in the amount of available terrigenous sediments and the inadequate design of coastal protection structures, all of them have dramatically reduced the resilience of coastal ecosystems. Considering that population growth, and the increasing needs for goods and services add pressure to coasts, several actions are suggested to reinforce the resilience of the coast of Veracruz: (a) It is vital to recover the sources of terrestrial sediments, move or remove infrastructure or implement sand bypass when possible; (b) it is urgent to consider ecosystem-based coastal zone management; (c) without a proper diagnosis of the status of the coast, coastal management may result in increased environmental problems and risk. These points can be applied elsewhere, as the problems are often very similar. Coastal managers, ecologists, engineers, decision makers and society in general are jointly responsible of the future of the fragile and dynamic coasts.