Abstract Water resource management is a major concern in Marquenterre, a maritime plain located in the western part of the Somme department. Water management is particularly indispensable for protecting wetlands in Marquenterre, regulating water usage and avoiding saline intrusion into aquifers. Various approaches including geological modelling and hydrogeological and hydrogeochemical studies were used to prepare a conceptual model of the Marquenterre hydrosystem and to provide better water management in this sector. The conceptual model shows that the chalk aquifer and the various Quaternary deposit aquifers are in hydrogeological continuity. No seawater intrusion has been discovered in groundwater. Salinization discovered at depth is a result of the most recent marine transgressions. Finally, wetlands are primarily supplied by the chalk groundwater or by rainfall. The study results are used to direct policies for surface and subsurface water resource management. The proposed conceptual model may be useful for other coastal aquifers along the English Channel in order to address challenges of managing the chalk groundwater and backshore swamps.

Abstract Coastal ecosystems consist of diverse habitats, such as reed beds, salt marshes, mangrove swamps, tidal flats, river deltas, seagrass fields, coral reefs, sandy/rocky-shore beaches and other habitats that harbour biodiversity. The Great East Japan Earthquake of March 2011 caused severe damage to one-third of the fishing communities along the Pacific Ocean of NE Japan. Coastal species, such as seagrasses, function as nursery areas for commercially important species. Coastal ecosystems provide natural infrastructure for the prevention and reduction of hazardous events, a process known as ecosystem-based disaster risk reduction (Eco-DRR). The preparation of topographic and thematic maps of coastal marine environments is essential to establish and visualize the concept of Eco-DRR. Experience gained following the Japanese earthquake, as well as examples from Indonesia and Thailand in the wake of 2004 Indian Ocean tsunami, showed that Eco-DRR is an affordable and sustainable approach. Dissemination of habitat maps should be further promoted as a way to ‘Build Back Better’. To scale up and promote Eco-DRR, scientists must work in a transdisciplinary manner and engage with society by understanding the roles of ecosystems by monitoring and analysing, providing solutions and raising the awareness of community and policy makers, enabling them to better implement Eco-DRR.

Abstract The latest early Campanian archipelago deposits of the Kristianstad Basin, southern Sweden, yield one of the most diverse Cretaceous chondrichthyan faunas collected from a narrow stratigraphical interval. Building on previous descriptions of various selachians, squatiniform and synechodontiform sharks are added to the faunal list. Squatinidae is represented by Squatina ( Squatina ) lundegreni sp. nov. and Squatina ( Squatina ) fortemordeo sp. nov. The poorly preserved type specimens of the nominal Squatina hassei from the Maastrichtian of The Netherlands were recently regarded conspecific with better preserved Santonian–Maastrichtian teeth of Squatina ( Cretascyllium ) from the Anglo-Paris Basin. This appears to have been based largely on the assumption that the nominal S . hassei was the only Squatina present in NW Europe during the Santonian–Maastrichtian. The Swedish material indicates a greater diversity of squatinoids, and the nominal S . hassei is here regarded as a nomen dubium of uncertain subgeneric affinity. Two types of synechodontid teeth with a tall central cusp co-occur in the Campanian of the Kristianstad Basin. Based on articulated jaws of the markedly dignathic S . dubrisiensis from the Cenomanian of England, the two morphs are regarded as upper and lower anterior teeth of the single species S . filipi sp. nov.

Puerto Rico's high population density (430/km 2 ) and concentrated development in the coastal zone result in communities that are highly to extremely vulnerable to coastal hazards. Tsunamis pose the greatest extreme risk (e.g., 1867 southeast coast; 1918 northwest coast), and westward-moving hurricanes have a history of severe impact (e.g., Hurricane Hugo, 1989; San Ciriaco Hurricane, 1899). The north and west coasts experience far-traveled swell from North Atlantic winter storms (e.g., the Perfect Storm of 1991) which severely impact the coast. Sea-level rise threatens flooding of low-lying coastal mangroves, wetlands, and low-elevation developments, and erosion of wave-cut bluffs will accelerate (e.g., south coast Municipios [equivalent of counties] of Arroyo and Guayama, just west of Cabo Mala Pascua). Anthropogenic effects have seriously modified coastal processes to create high- to extreme-risk zones. Examples include removal of protective dunes and beach sediment by sand mining (e.g., Piñones, Caribe Playa Seabeach Resort, and Camuy), and erosional impacts due to marinas (e.g., erosion rates of 3 m/yr in Rincón area due to Punta Ensenada marina). Communities have taken poor courses in erosion control by emplacing shore-hardening structures along over 50 separate coastal stretches (e.g., seawalls at San Juan Harbor and Arecibo; groins in Ensenada de Boca Vieja), and utilizing poor construction designs (e.g., gabions). Beach profiling reveals that beaches narrow and disappear in front of such structures (no dry beach in front of 55% of seawalls surveyed). Mitigation must come through prohibiting construction in high-risk zones, encouraging wider adoption of setback principles (e.g., Villa Palmira), relocating after storms, enforcing anti–sand-mining regulations, and better public education.

The fossil record of wetlands documents unique and long-persistent floras and faunas with wetland habitats spawning or at least preserving novel evolutionary characteristics and, at other times, acting as refugia. In addition, there has been an evolution of wetland types since their appearance in the Paleozoic. The first land plants, beginning in the Late Ordovician or Early Silurian, were obligate dwellers of wet substrates. As land plants evolved and diversified, different wetland types began to appear. The first marshes developed in the mid-Devonian, and forest swamps originated in the Late Devonian. Adaptations to low-oxygen, low-nutrient conditions allowed for the evolution of fens (peat marshes) and forest mires (peat forests) in the Late Devonian. The differentiation of wetland habitats created varied niches that influenced the terrestrialization of arthropods in the Silurian and the terrestrialization of tetrapods in the Devonian (and later), and dramatically altered the way sedimentological, hydrological, and various biogeochemical cycles operated globally. Widespread peatlands evolved in the Carboniferous, with the earliest ombrotrophic tropical mires arising by the early Late Carboniferous. Carboniferous wetland-plant communities were complex, and although the taxonomic composition of these wetlands was vastly different from those of the Mesozoic and Cenozoic, these communities were essentially structurally, and probably dynamically, modern. By the Late Permian, the spread of the Glossopteris flora and its adaptations to more temperate or cooler climates allowed the development of mires at higher latitudes, where peats are most common today. Although widespread at the end of the Paleozoic, peat-forming wetlands virtually disappeared following the end-Permian extinction. The initial associations of crocodylomorphs, mammals, and birds with wetlands are well recorded in the Mesozoic. The radiation of Isoetales in the Early Triassic may have included a submerged lifestyle and hence, the expansion of aquatic wetlands. The evolution of heterosporous ferns introduced a floating vascular habit to aquatic wetlands. The evolution of angiosperms in the Cretaceous led to further expansion of aquatic species and the first true mangroves. Increasing diversification of angiosperms in the Tertiary led to increased floral partitioning in wetlands and a wide variety of specialized wetland subcommunities. During the Tertiary, the spread of grasses, rushes, and sedges into wetlands allowed for the evolution of freshwater and salt-water reed marshes. Additionally, the spread of Sphagnum sp. in the Cenozoic allowed bryophytes, an ancient wetland clade, to dominate high-latitude mires, creating some of the most widespread mires of all time. Recognition of the evolution of wetland types and inherent framework positions and niches of both the flora and fauna is critical to understanding both the evolution of wetland functions and food webs and the paleoecology of surrounding ecotones, and is necessary if meaningful analogues are to be made with extant wetland habitats.

The Fayetteville Formation of northwestern Arkansas (upper Mississippian/middle Chesterian) contains two compression plant fossil assemblages (one in situ) that represent plant communities, and an allochthonous permineralized assemblage recovered from marine strata that represents the landscape. This preservation of spatial ecological subunits (communities) nested within a larger subunit (landscape) provides a snapshot of vegetation patterns within a Late Mississippian clastic swamp. Fifteen whole plants are recognized. Seed ferns are the most speciose group and lycopsids account for most biomass. Seed fern taxa known only as permineralized specimens include one canopy tree ( Megaloxylon ), two understory trees, and five herbaceous layer plants. Two herbaceous layer seed ferns are observed only as compressions. Lycopsids are represented as two canopy trees that are known from both permineralizations and compressions. Archaeocalamites is also known from both permineralizations and compressions but was an understory tree. Ferns are rare and are preserved only as fragments of permineralized rachises from two species. As revealed by the in situ compression assemblage, the two species of lycopsid canopy trees co-occur and they formed communities that occupied ever-wet bottomlands, with Archaeocalamites occupying the understory, and a single species of seed fern comprising the herbaceous layer. Lycopsids do not co-occur with Megaloxylon . Megaloxylon probably formed a second community type in somewhat water-stressed areas of the swamp with an understory of small arborescent seed ferns, some Archaeocalamites , and an herbaceous-layer seed fern. Ferns probably formed a third type of community in disturbed sites.

Dedicated to the memory of William T. Holser, colleague and friend. A gap in the fossil record of coals and coral reefs during the Early Triassic follows the greatest of mass extinctions at the Permian-Triassic boundary. Catastrophic methane outbursts during terminal Permian global mass extinction are indicated by organic carbon isotopic (δ 13 C org ) values of less than –37‰, and preferential sequestration of 13 C-depleted carbon at high latitudes and on land, relative to low latitudes and deep ocean. Methane outbursts massive enough to account for observed carbon isotopic anomalies require unusually efficient release from thermal alteration of coal measures or from methane-bearing permafrost or marine methane-hydrate reservoirs due to bolide impact, volcanic eruption, submarine landslides, or global warming. The terminal Permian carbon isotopic anomaly has been regarded as a consequence of mass extinction, but atmospheric injections of methane and its oxidation to carbon dioxide could have been a cause of extinction for animals, plants, coral reefs and peat swamps, killing by hypoxia, hypercapnia, acidosis, and pulmonary edema. Extinction by hydrocarbon pollution of the atmosphere is compatible with many details of the marine and terrestrial fossil records, and with observed marine and nonmarine facies changes. Multiple methane releases explain not only erratic early Triassic carbon isotopic values, but also protracted (∼6 m.y.) global suppression of coral reefs and peat swamps.