TL;DR: This study reports a first detailed bacterial inventory from vertical profiles of 60 sampling stations distributed along the salinity gradient of the Baltic Sea, one of world's largest brackish water environments, generated using 454 pyrosequencing of partial (400 bp) 16S rRNA genes.
Abstract: Salinity is a major factor controlling the distribution of biota in aquatic systems, and most aquatic multicellular organisms are either adapted to life in saltwater or freshwater conditions. Consequently, the saltwater–freshwater mixing zones in coastal or estuarine areas are characterized by limited faunal and floral diversity. Although changes in diversity and decline in species richness in brackish waters is well documented in aquatic ecology, it is unknown to what extent this applies to bacterial communities. Here, we report a first detailed bacterial inventory from vertical profiles of 60 sampling stations distributed along the salinity gradient of the Baltic Sea, one of world's largest brackish water environments, generated using 454 pyrosequencing of partial (400 bp) 16S rRNA genes. Within the salinity gradient, bacterial community composition altered at broad and finer-scale phylogenetic levels. Analogous to faunal communities within brackish conditions, we identified a bacterial brackish water community comprising a diverse combination of freshwater and marine groups, along with populations unique to this environment. As water residence times in the Baltic Sea exceed 3 years, the observed bacterial community cannot be the result of mixing of fresh water and saltwater, but our study represents the first detailed description of an autochthonous brackish microbiome. In contrast to the decline in the diversity of multicellular organisms, reduced bacterial diversity at brackish conditions could not be established. It is possible that the rapid adaptation rate of bacteria has enabled a variety of lineages to fill what for higher organisms remains a challenging and relatively unoccupied ecological niche.
TL;DR: In this article, the average soil carbon density of mangrove swamps (0.055 ± 0.004 g cm−3) is significantly higher than the salt marsh average ( 0.039 − 0.003 g cm −3) due to increased decay rates at higher temperatures.
Abstract: [1] Wetlands represent the largest component of the terrestrial biological carbon pool and thus play an important role in global carbon cycles. Most global carbon budgets, however, have focused on dry land ecosystems that extend over large areas and have not accounted for the many small, scattered carbon-storing ecosystems such as tidal saline wetlands. We compiled data for 154 sites in mangroves and salt marshes from the western and eastern Atlantic and Pacific coasts, as well as the Indian Ocean, Mediterranean Ocean, and Gulf of Mexico. The set of sites spans a latitudinal range from 22.4°S in the Indian Ocean to 55.5°N in the northeastern Atlantic. The average soil carbon density of mangrove swamps (0.055 ± 0.004 g cm−3) is significantly higher than the salt marsh average (0.039 ± 0.003 g cm−3). Soil carbon density in mangrove swamps and Spartina patens marshes declines with increasing average annual temperature, probably due to increased decay rates at higher temperatures. In contrast, carbon sequestration rates were not significantly different between mangrove swamps and salt marshes. Variability in sediment accumulation rates within marshes is a major control of carbon sequestration rates masking any relationship with climatic parameters. Globally, these combined wetlands store at least 44.6 Tg C yr−1 and probably more, as detailed areal inventories are not available for salt marshes in China and South America. Much attention has been given to the role of freshwater wetlands, particularly northern peatlands, as carbon sinks. In contrast to peatlands, salt marshes and mangroves release negligible amounts of greenhouse gases and store more carbon per unit area.
TL;DR: A review of salt marsh ecosystems can be found in this article, where the authors discuss the role of salt marshes as part of coastal landscapes and their role in the evolution of salt-grass communities.
Abstract: Foreword. Dedication. Preface. Retrospective on the Salt Marsh Paradigm. Tidal marshes as outwelling/pulsing systems E.P. Odum. Salt marsh values: etrospection from the end of the century J.M. Teal, B.L. Howes. Sources and Patterns of Production. Role of salt marshes as part of coastal landscapes I. Valiela, et al. Spatial variation in process and pattern in salt marsh plant communities in eastern North America M.D. Bertness, S.C. Pennings. Eco-physiological controls on the productivity of Spartina alterniflore I.A. Menselssohn, J.T. Morris. Community structure and functional dynamics of benthic microalgae in salt marshes M.J. Sullivan, C.A. Currin. Structure and productivity of microtidal Mediterranean coastal marshes C. Ibanez, et al. Development and structure of salt marshes: community patterns in time and space A.J. Davy. Fate of Production Within Marsh Food Webs. Microbial secondary production from salt marsh-grass shoots, and its known and potential fates S.Y. Newell, D. Porter. Trophic complexity between producers and invertebrate consumers in salt marshes D.A. Kreeger, R.I.E. Newell. Trophic linkages in marshes: ontogenetic changes in diet for young-of-the-year mummichog, Fundulus heteroclitus K.J. Smith, et al. Habitat Value: Food and/or Refuge. Factors influencing habitat selection in fishes with a review of marsh ecosystems J.K. Craig, L.B. Crowder. Salt marsh ecoscapes and production transfers by estuarine nekton in the southeastern U.S. R.T. Kneib. Salt marsh linkages to productivity of penaeid shrimps and blue crabs in the northern Gulf of Mexico R.J. Zimmerman, et al. Ecophysiological determinants ofsecondary production in salt marshes: a simulation study J.M. Miller, et al. Salt marsh ecosystem support of marine transient species L.A. Deegan, et al. Biogeochemical Processes. Benthic-pelagic coupling in marsh-estuarine ecosystems R.F. Dame, et al. Twenty more years of marsh and estuarine flux studies: revisiting Nixon (1980) D.L. Childers, et al. The role of oligohaline marshes in estuarine nutrient cycling J.Z. Merrill, J.C. Cornwell. Molecular tools for studying biogeochemical cycling in salt marshes L. Kerkhof, D.J. Scala. Nitrogen and vegetation dyamics in European salt marshes J. Rozema, et al. Modeling Nutrient and Energy Flux. A stable isotope model approach to estimating the contribution of organic matter from marshes to estuaries P.M. Eldrige, L.A. Cifuentes. Types of salt marsh edge and export of trophic energy from marshes to deeper habitats G. Cichetti, R.J. Diaz. Silicon is the link between tidal marshes and estuarine fisheries: a new paradigm C.T. Hackney, et al. Tidal Marsh Restoration: Fact or Fiction? Self-design applied to coastal restoration W.J. Mitsch. Functional equivalency of restored and natural salt marshes J.B. Zedler, R. Lindig-Cisneros. Organic and inorganic contributions to vertical accretion in salt marsh sediments R.E. Turner, et al. Landscape structure and scale constraints on restoring estuarine wetlands for Pacific coast juvenile fishes C.A. Simenstad, et al. Ecological Engineering of Restored Marshes. The role of pulsing events in the functioning of coastal barriers and wetlands: implications for human impact, management and the response to sea level rise J.W. Day, et al. Influences of vegetation and abiotic environmental f
TL;DR: In this paper, it was shown that the evolution from an organogenic to a sequence of mineralogenic marshes (transgressive overlaps) is accompanied by the initiation and invasive development of a branching network of tidal creeks.
TL;DR: In this paper, the authors investigated the role of aggressive clones in the expansion of Phragmites into tidal wetlands of North America and found that over 80% of the US coastal wetland area occurs along the Gulf of Mexico and southern Atlantic coasts and may be susceptible to ongoing expansion.