Agglutinated foraminifera dominate in temperate salt marsh sediment, making them key indicators for monitoring sea level and environmental changes. Little is known about the biology of these benthic foraminifera because of difficulties in distinguishing live from dead specimens in laboratory cultures. We present data from 10 years of laboratory experiments using comparisons of the agglutinant trochamminids Trochammina inflata and Entzia macrescens and the miliolid Miliammina fusca with the calcareous rotalids Helenina anderseni and Elphidium williamsoni. Specimens were taken from a laboratory mesocosm representing Chezzetcook Inlet, a cool-temperate salt marsh in eastern Canada. We determined culture requirements for the agglutinated foraminifera in Petri dishes over 10–12 week periods. Five inexpensive, non-terminal ways of identifying live organisms were developed: spatial movement, detritus-gathering, attachment, clustering, and test opacity. Comparison with rose Bengal staining showed <10% diversion for calcareous species and T. inflata but M. fusca was over-counted by >30%. Terminal chambers of Trochammina inflata were examined by transmission electron microscopy to visualise food consumption and identify food in digestive vacuoles, both in specimens from mesocosm and in culture. Bacteria and unidentified detritus in the vacuoles establish that this agglutinated species is a saprophagous and bacterivorous detritivore. The adhesive secretions by these species apparently help them gather and possibly farm food while being relatively immobile in the sediments. Our observations of movement and feeding orientation in the agglutinants suggest links between form and function that underscore their value as ultra high resolution sea-level proxies. Mesocosm biomass and abundance counts show that foraminifera represent >50% of the meiofaunal biomass, emphasising their importance in the food web and energy-flow dynamics of temperate salt marsh systems.

In this paper, we reconstruct the Holocene paleoenvironmental evolution of the Guadiana Estuary, southwestern Iberian Peninsula. Two previously studied boreholes (CM3 and CM5) were revisited and analyzed in the light of a foraminifera modern analog approach. Cluster analyses define four assemblages with different biocenotic, taphonomic, elevation and distance-to-sea settings, which serve as a baseline for paleoassemblages interpretation. Faunal changes along the sedimentary sequences, together with previous sedimentological and chronological data, redefine the different phases of environmental evolution in the Guadiana Estuary since ca. 13 kyr cal. BP, with special emphasis on the Holocene marine highstand. Estuarine flooding began synchronously in both locations (ca. 9 kyr cal. BP) but manifested differently in each sedimentary sequence. The most seaward borehole records a more evident and longer highstand (ca. 8.8–3.8 kyr cal. BP), characterized by the occurrence of subtidal environments and by the presence of open marine species ( Pararotalia cf. spinigera, planktic forms and a significant number of exotic/allochthonous tests), indicating warmer and more marine conditions than today. In the most landward borehole, the highstand is shorter (ca. 8–7.6 kyr cal. BP) and less intense, characterized by the presence of a diverse, mainly autochthonous, open estuary assemblage, dominated by Ammonia aberdoveyensis and Haynesina germanica. At 4.4 kyr cal. BP, during a long deceleration phase of regional sea-level rise, a short but well-defined pulse of marine influence is recorded in CM5, when open estuarine assemblages reappear and replace marsh agglutinated assemblages, suggesting a new submergence phase. This short event is not identified in the previous works carried out in the same area, thus further data are needed to understand whether it is consequent from a global, warming period or whether it resulted only from local and ephemeral forcing effects.

The present study analyzes the spatial distribution and seasonal distribution of live benthic foraminiferal communities in the estuary of Guadiana, the fourth largest river on the Iberian Peninsula, and establishes, through statistical analysis, their relationships with a series of environmental parameters. Forty-four superficial sediment samples were collected along distance-to-sea and elevation gradients in the winter and summer of 2010. Fifty-three foraminifera species were identified along the intertidal margins of the estuary. Foraminiferal distribution reflected seasonal variation of environmental factors, whose relative importance varied according to species tolerances. Elevation in relation to mean sea level appeared to be the most important parameter controlling foraminiferal distribution, probably because it combines the effects of a series of other variables (i.e. organic matter, sediment texture, pH and temperature). In the highest marsh areas, where environmental conditions approach survival thresholds, only some agglutinated species are able to survive. In the lower intertidal zone, where subaerial exposure is diminished and environmental conditions are generally less variable, more diverse faunas, mainly composed of calcareous species, prevail. During winter, when fluvial discharge peaks, agglutinated species represent more than 80% of the total individuals. In summer, when marine conditions prevail, calcareous species become more competitive, increase their densities and expand into higher marsh zones and estuarine upper reaches. In the estuary, three different foraminiferal assemblages are distinguished: i) Miliammina fusca assemblage, which dominates in unvegetated areas of the lower marsh and tidal flats of the mid-upper estuary; ii) Jadammina macrescens assemblage, which dominates in the highest marsh areas in the lower estuary; and iii) Ammonia aberdoveyensis assemblage, which dominates the areas of low marsh and tidal flats of the lower estuary.

The present study gathers pioneering taxonomical and community data on testate amoebae and agglutinated tintinnids, analyzing their seasonal and spatial distribution patterns in the mesotidal system of the Guadiana Estuary, southeastern Portugal. To evaluate both groups' potential as bioindicators in climate monitoring and paleoenvironmental reconstructions, their abundance, diversity and living proportions were compared to elevation in relation to mean sea-level, marine influence and to periods of elevated water levels. The distributions of testate amoebae and tintinnid total assemblages were also related to major physicochemical variables by means of multivariate analysis.From 49 surface sediment samples collected in winter and summer 2010, 17 species (25 strains) of testate amoebae were identified (in the 63 pm fraction). The Centropyxidae, mainly represented by Centropyxis aculeata, Centropyxis arcula and Centropyxis constricta, had the greatest density (71% of total individuals), while the Difflugidae represented the most species (82% of total species). Higher diversities and densities were observed in winter in the upper estuary, where salinity is negligible, and in the middle estuary where they are concentrated at the lower levels of the intertidal zone. Few or no individuals were observed in the highest marsh zones. In winter, dead testate amoebae were dominant, with empty tests accumulating in the sediments from post-mortem transport by high river discharge. In summer, an increase in the living fraction is observed, with living testate amoebae along the entire estuary, which could indicate that some species are able to live in the lower reaches of the estuary.Along with the testate amoebae, two species of agglutinated tintinnids (>63 mu m), Stenosemella ventricosa and Tintinnopsis cf. lata, were abundant in the sediments. Their highest abundances were observed in summer. Living individuals were only recorded in summer, mainly in the vicinities of freshwater and sewage outflows, where elevated nutrient concentrations may be expected.The present study demonstrates that both testate amoebae and tintinnids have well defined patterns in their temporal and spatial distribution, offering high bioindicator potential in environmental/climate monitoring studies as well as in paleoenvironmental reconstructions. (C) 2015 Elsevier Ltd. All rights reserved.

Salt marshes and mangrove forests, the intertidal wetlands of the world's coastlines, provide key ecological services to all areas of the globe. This cutting-edge, richly illustrated book introduces the essential elements of coastal wetlands and their applications. The book opens by introducing coastal oceanography, the physical features of wetlands, their ecology, and human impacts upon them, giving all students the necessary background for wetlands studies. It then presents detailed case studies from around the world with extensive illustrations, supplying a wider, global-scale picture of wetlands geomorphology and biodiversity. The final chapters discuss some unique applications of coastal wetlands, including geological monitoring, uses in biotechnology and agriculture, and various experimental mesocosms. This is ideal as supplementary reading to support students on a wide range of earth and life science courses, from environmental science, ecology and palaeoecology to geomorphology and geography. It will also be a valuable interdisciplinary reference for researchers.

This study analyses the taxonomy, ecology and biogeography of the species of benthic foraminifera living on the intertidal margins of the Guadiana Estuary (SE Portugal, SW Spain). Of the 54 taxa identified during sampling campaigns in winter and summer, 49 are systematically listed and illustrated by scanning electron microscope (SEM) photographs. Ammonia spp. were the most ubiquitous calcareous taxa in both seasons. Morphological analysis and SEM images suggested three distinct morphotypes of the genus Ammonia, two of which proved to be Ammonia aberdoveyensis on the basis of partial rRNA analyses. Jadammina macrescens and Miliammina fusca were the most ubiquitous agglutinated taxa in the estuary. Jadammina macrescens dominates the upper-marsh zones almost exclusively, occurring at very high densities. Ammonia spp. are the most abundant in the low-marsh and tidal-flats of the lower reaches of the Guadiana Estuary, but are widespread throughout the estuary, especially during summer when environmental conditions favor their proliferation. Miliammina fusca dominates the sparsely vegetated low-marsh and tidal-flat zones of the upper reaches, where it is associated with calcareous species. Due to its geographical position, the Guadiana system shares characteristics of both Atlantic and Mediterranean estuaries. This is reflected in the foraminiferal assemblages, with a dominance of thermophilous species and an ecological zonation typical of the Mediterranean climatic zone.

North Atlantic climate archives provide evidence for increased storm activity during the Little Ice Age (150 to 600 calibrated years (cal years) B.P.) and centered at 1700 and 3000cal years B.P., typically in centennial-scale sedimentary records. Meteorological (tropical versus extratropical storms) and climate forcings of this signal remain poorly understood, although variability in the North Atlantic Oscillation (NAO) or Atlantic Meridional Overturning Circulation (AMOC) are frequently hypothesized to be involved. Here we present records of late Holocene storminess and coastal temperature change from a Bermudian submarine cave that is hydrographically circulated with the coastal ocean. Thermal variability in the cave is documented by stable oxygen isotope values of cave benthic foraminifera, which document a close linkage between regional temperature change and NAO phasing during the late Holocene. However, erosion of terrestrial sediment into the submarine cave provides a storminess signal that correlates with higher-latitude storminess archives and broader North Atlantic cooling events. Understanding the driver of this storminess signal will require higher-resolution storm records to disentangle the contribution of tropical versus extratropical cyclones and a better understanding of cyclone activity during hemispheric cooling periods. Most importantly, however, the signal in Bermuda appears more closely correlated with proxy-based evidence for subtle AMOC reductions than NAO phasing.

Key pointsCoastal ecosystem knowledge is essential for understanding earthquake mechanics and forecasting catastrophic shoreline movement and flooding; multiple sources of fossil proxy-data – including microfossils, pollen and sediment – are best used to reconstruct patterns of earthquakes and tsunamis in time and space; multidisciplinary studies are also needed to distinguish tsunami from tropical storm events; correct measurement of timing and speed of paleoseismic events depend on accurate dating methods, best provided by tree roots and salt marsh peat; foraminifera provide the most precise estimates for amounts of vertical shoreline change; pollen of mangroves and salt marsh plants provide best estimates of climate change; diatom and dinoflagellate paleotransfer functions are best for tracking the prehistoric sea-ice changes.

Key pointsThe location of coastal wetlands on deltas, estuaries and lagoons make them targets for landscape alteration by dredging, shipping and air industries; land ‘reclamation’ for agriculture, aquaculture, urban development and tourism has transformed ~30% of the world’s wetlands; population growth, rising sea level, dams and soil desiccation increase wetlands flooding from higher water levels and increased storminess; shrinking Arctic sea ice, permafrost and glacier melting increase erosion, adding to greenhouse gases and change ocean–atmosphere circulations pole-to-pole; replacing salt marsh and mangroves by landfill removes natural shoreline protection, but artificial barriers create worse erosion; attempted wetland recolonization often fails because introduced species are invasive; drainage to control mosquitos and tropical diseases changes wetland productivity; pollution from nitrogen loading and oil spills cause long-lasting damage, up to >30 years.

Key pointsAll wetland ecosystems provide valuable services to local people and influence global carbon budgets; climate delimits four major ecosystems: arctic and subpolar marshes, temperate marshes, subtropical tidal wetlands and tropical mangrove swamps; wetlands worldwide have specialized plant forms adapted to physical extremes of soil salinity, instability and low oxygen; global biogeographic studies are the tools of wetlands biodiversity studies; primary regional differences in species composition reflect ancient paleogeographic changes; plate tectonics and icesheets isolated tropical 'Old World' from 'New World' biological provinces; coastal wetlands are azonal vegetation types highly influenced by soil conditions; differences in temperature and precipitation regimes shift the ecosystem boundaries north or south on different coasts of continents; seasonal variations in temperature–precipitation conditions drive subregional soil water salinity differences.

Coastal wetlands, including tidal salt marshes and mangrove swamps, are environmentally stressful and variable habitats, and yet are teeming with life. Their biological productivity exceeds that of coral reefs and matches that of tropical rainforests. These wetlands provide resident plants and animals with shelter, food and continuous renewal of nutrients on each tidal cycle. These coastal wetlands are also vital to neighbouring ecological communities and have important values to humans, serving as natural carbon-capture systems, as sources of oceanic ‘blue carbon’, as filters of sediment or nutrient-loaded flood water and as buffers against storm tides and rising sea levels. Concern about the twentieth-century destruction of many wetlands in North America, Europe, Australia and New Zealand, and the degradation of wetlands worldwide led to the 1971 Ramsar Convention on Wetlands, held on the shore of the Caspian Sea in Iran (see Box 1.1 The Ramsar Convention). The Convention provides foundations for planning of ‘wise use’ for all wetlands; preservation of wetlands with international importance for ecology, biodiversity or hydrology; and co-operative protection of internationally shared species. Coupled with this landmark environmental agreement, the United Nations designated 2 February as ‘World Wetlands Day’, bracketing it with programmes to raise awareness of the strong link between global freshwater supplies and wetland resources. These two themes ‘Water’ and ‘Wetlands’ highlight global efforts to promote understanding that without coastal wetland conservation, there will not be enough water for sustainable development, human health and, ultimately, the survival of humankind.

The McMurdo Dry Valleys comprise the largest relatively ice-free area in Antarctica and are characterized by low precipitation rates. Perennial ice cover on the dry valley lakes decreases the amount of solar radiation reaching the water column, thereby reducing the interaction between the atmosphere and the water column. However, the ice partly shelters the lake ecosystems from the harsh Antarctic climate. Two cores, collected from Lake Hoare in the Taylor Valley in 1995, contained testate rhizopods (mostly Arcella) that have only chitinous organic tests with no agglutinated material, unlike other testate rhizopods that use detrital material to build a test. Additionally, a limited number of possible ostracod carapaces and possible rotifer resting-stage remains were present. The testate rhizopod concentration is generally higher in layers containing abundant bacterial/algal-mat fragments. This reflects the local sedimentation pattern in which layers of alternating mat growth and sediment accumulation on the ice surface subsequently fall to the lake bottom.