A snapshot of parasites in tropical and subtropical freshwater wetlands: modest attention for major players

Viruses are the most abundant and ubiquitous biological entities in various ecosystems, yet few investigations of viral communities in wetlands have been performed. To address this data gap, water samples from 6 wetlands were randomly collected across northeast China; viruses in the water were concentrated by sequential tangential flow filtration, and viral communities were assessed through randomly amplified polymorphic DNA-PCR (RAPD-PCR) with 4 decamer oligonucleotide primers. Principal coordinate analysis and hierarchical clustering analysis of the DNA fingerprints showed that viral community compositions differed among the water samples: communities in the 2 coastal wetlands were more similar to each other than to those in the 4 freshwater wetlands. The Shannon-Weaver index (H) and evenness index (E) of the RAPD-PCR fingerprint also differed among the 6 wetlands. Mantel test revealed that the changes in viral communities in wetland water were most closely related to the water NH4+-N and inorganic C content, followed by total K, P, C and NO3--N. DNA sequence analysis of the excised bands revealed that viruses accounted for ~40% of all sequences. Among the hit viral homologs, the majority belonged to the Microviridae. Moreover, variance partitioning analysis showed that the viral community contributed 24.58% while environmental factors explained 30.56% of the bacterial community variation, indicating that the bacterial community composition was strongly affected by both viral community and water variables. This work provides an initial outline of the viral communities from different types of wetlands in northeast China and improves our understanding of the viral diversity in these ecosystems.

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Soil Organic Carbon and Nitrogen Variations with Vegetation Succession in Passively Restored Freshwater Wetlands

Wetlands ◽

10.1007/s13157-021-01413-w ◽

2021 ◽

Vol 41 (1) ◽

Author(s):

Yu An ◽

Yang Gao ◽

Xiaohui Liu ◽

Shouzheng Tong ◽

Bo Liu ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Vegetation Succession ◽

Freshwater Wetlands ◽

Carbon And Nitrogen

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Managing agricultural grazing to enhance the carbon sequestration capacity of freshwater wetlands

Wetlands Ecology and Management ◽

10.1007/s11273-020-09780-7 ◽

2021 ◽

Author(s):

Katy E. Limpert ◽

Paul E. Carnell ◽

Peter I. Macreadie

Keyword(s):

Carbon Sequestration ◽

Freshwater Wetlands

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Effects of Grazer Exclusion on Carbon Cycling in Created Freshwater Wetlands

Land ◽

10.3390/land10080805 ◽

2021 ◽

Vol 10 (8) ◽

pp. 805

Author(s):

Delanie M. Spangler ◽

Anna Christina Tyler ◽

Carmody K. McCalley

Keyword(s):

Soil Carbon ◽

Carbon Cycling ◽

Belowground Biomass ◽

Freshwater Wetlands ◽

Wetland Creation ◽

Free Access ◽

Exclusion Experiment ◽

Herbivore Exclusion ◽

Sequestration Potential ◽

Natural Wetlands

Wetland ecosystems play a significant role in the global carbon cycle, and yet are increasingly threatened by human development and climate change. The continued loss of intact freshwater wetlands heightens the need for effective wetland creation and restoration. However, wetland structure and function are controlled by interacting abiotic and biotic factors, complicating efforts to replace ecosystem services associated with natural wetlands and making ecologically-driven management imperative. Increasing waterfowl populations pose a threat to the development and persistence of created wetlands, largely through intensive grazing that can shift vegetation community structure or limit desired plant establishment. This study capitalized on a long-term herbivore exclusion experiment to evaluate how herbivore management impacts carbon cycling and storage in a created wetland in Western New York, USA. Vegetation, above- and belowground biomass, soil carbon, carbon gas fluxes and decomposition rates were evaluated in control plots with free access by large grazers and in plots where grazers had been excluded for four years. Waterfowl were the dominant herbivore at the site. Grazing reduced peak growing season aboveground biomass by over 55%, and during the summer, gross primary productivity doubled in grazer exclusion plots. The shift in plant productivity led to a 34% increase in soil carbon after exclusion of grazers for five growing seasons, but no change in belowground biomass. Our results suggest that grazers may inhibit the development of soil carbon pools during the first decade following wetland creation, reducing the carbon sequestration potential and precluding functional equivalence with natural wetlands.

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Correlations between environmental salinity levels, blood biochemistry parameters, and steroid hormones in wild juvenile American alligators (Alligator mississippiensis)

Scientific Reports ◽

10.1038/s41598-021-94557-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Patricia C. Faulkner ◽

Ruth M. Elsey ◽

David Hala ◽

Lene H. Petersen

Keyword(s):

Late Summer ◽

Storm Surges ◽

Freshwater Wetlands ◽

Alligator Mississippiensis ◽

Environmental Salinity ◽

Significant Seasonal Variation ◽

Freshwater Habitats ◽

Dry Conditions ◽

American Alligators ◽

One Year

AbstractAmerican alligators (Alligator mississippiensis) inhabit freshwater wetlands that are vulnerable to salinization caused by anthropogenic alterations to freshwater flow, in addition to storm surges, sea level rise, and droughts. Salinization of coastal freshwater habitats is a growing concern in a changing climate due to increased frequency and intensity of storm surges and drought conditions. This study opportunistically sampled juvenile male and female wild alligators in various salinities each month excluding November, December, and January for one year at Rockefeller Wildlife Refuge in coastal Louisiana. Blood plasma biochemistry parameters including electrolyte levels were subsequently measured. In addition, levels of various renin–angiotensin–aldosterone system hormones, glucocorticoids, androgens, estrogens, and progestogens were analyzed using liquid chromatography and tandem mass spectrometry. Only males were sampled in hyperosmotic environments (> 10‰) during dry conditions in late summer 2018. In juvenile males, plasma Na+, Cl−, and the progestogen 17α,20β-dihydroxypregnenone were significantly and positively correlated with environmental salinity. However, variation in glucocorticoids, androgens, and estrogens were not associated with hypersaline water while sex steroids showed significant seasonal variation. This study demonstrated significant correlation of environmental salinity with electrolyte levels and a sex steroid in wild juvenile alligators, and to our knowledge represents the first measurement of 17α,20β-dihydroxypregnenone in alligators.

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Juvenile Salmonid Use of Reconnected Tidal Freshwater Wetlands in Grays River, Lower Columbia River Basin

Transactions of the American Fisheries Society ◽

10.1577/t09-082.1 ◽

2010 ◽

Vol 139 (4) ◽

pp. 1211-1232 ◽

Cited By ~ 33

Author(s):

G. Curtis Roegner ◽

Earl W. Dawley ◽

Micah Russell ◽

Allan Whiting ◽

David J. Teel

Keyword(s):

River Basin ◽

Columbia River ◽

Tidal Freshwater ◽

Freshwater Wetlands ◽

Columbia River Basin ◽

Tidal Freshwater Wetlands

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Typha productivity in a Texas pond: Implications for energy and nutrient dynamics in freshwater wetlands

Aquatic Botany ◽

10.1016/0304-3770(87)90075-1 ◽

1987 ◽

Vol 27 (4) ◽

pp. 385-394 ◽

Cited By ~ 14

Author(s):

B.H. Hill

Keyword(s):

Nutrient Dynamics ◽

Freshwater Wetlands

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Sedimentology, faunal content and pollen record of Middle Pleistocene palustrine and lagoonal sediments from the Peri-Adriatic basin, Abruzzi, eastern central Italy

Quaternary Research ◽

10.1016/j.yqres.2016.08.003 ◽

2016 ◽

Vol 86 (3) ◽

pp. 359-372 ◽

Cited By ~ 6

Author(s):

Pierluigi Pieruccini ◽

Claudio Di Celma ◽

Federico Di Rita ◽

Donatella Magri ◽

Giorgio Carnevale ◽

...

Keyword(s):

Shallow Water ◽

Sea Level ◽

Central Italy ◽

Freshwater Wetlands ◽

Middle Pleistocene ◽

Pollen Record ◽

Vegetation Development ◽

Oxygen Isotope Stage ◽

Open Forest ◽

Facies Succession

AbstractA 25 m-thick outcrop section exposed at Torre Mucchia, on the sea-cliff north of Ortona, eastern central Italy, comprises a rare Middle Pleistocene succession of shallow-water and paralic sediments along the western Adriatic Sea. An integrated study of the section, including facies and microfacies analyses, and characterization of paleobiological associations (mollusks, fishes, ostracods, foraminifers and pollen), enable a detailed reconstruction of the paleoenvironmental and paleoclimatic conditions during deposition. The shallow-water deposits include a transgressive, deepening- and fining-upward shoreface to offshore-transition facies succession overlain by a regressive shoreface-foreshore sandstone body with an erosive base and a rooted and pedogenically altered horizon at the top that imply deposition during sea-level fall. This forced regressive unit is overlain by paralic strata forming a transgressive succession comprising palustrine carbonates and back-barrier lagoonal mudstones. The palustrine carbonates exhibit some of the typical features encountered in palustrine limestones deposited within seasonal freshwater wetlands (marl prairies). Following the sea-level rising trend, the freshwater marshes were abruptly replaced by a barrier-lagoon system that allowed deposition of the overlying mud-rich unit. Within these deposits, the faunal assemblages are consistent with a low-energy brackish environment characterized by a relatively high degree of confinement. The pollen record documents the development of open forest vegetation dominated by Pinus and accompanied by a number of mesophilous and thermophilous tree taxa, whose composition supports a tentative correlation with Marine Oxygen Isotope Stage 17. The new pollen record from Torre Mucchia improves our understanding of the vegetation development in the Italian Peninsula during the Middle Pleistocene and sheds new light on the role played by the most marked glacial periods in determining the history of tree taxa.

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