Persistence of an amphibian ranavirus in aquatic communities

2014 ◽  
Vol 111 (2) ◽  
pp. 129-138 ◽  
Author(s):  
AF Johnson ◽  
JL Brunner
Keyword(s):  
Aquatic Communities

The vegetation of the small rivers of Novosibirsk Region (a syntaxonomic essay)

2019 ◽  
pp. 3-27 ◽  
Author(s):  
L. M. Kipriyanova ◽  
M. A. Kleshchev
Keyword(s):  
Anthropogenic Impact ◽  
West Siberia ◽  
Steppe Zone ◽  
Small Rivers ◽  
Forest Steppe ◽  
Aquatic Communities ◽  
Emergent Plants ◽  
Novosibirsk Region ◽  
General Chemical ◽  
Wide Range

Information on the aquatic and semiaquatic vegetation of the major watercourses of West Siberia is relatively scarce, while this of small rivers is practically absent. There are 430 rivers whose length exceeds 10 km within the Novosibirsk Region. The aim of our work was to study the phytocenotic diversity of their aquatic and semiaquatic vegetation. 130 geobotanical relevés were performed by the authors in July–August 2003–2005. The object was aquatic communities formed by true aquatic (submergent and floating-leaved) plants and semiaquatic ones with emergent plants and these of water′s edge. In total 10 watercourses were studied (Table 1): 2–3 in each of five geomorphologic regions within the forest-steppe zone (Table 2). The upper, middle and lower courses (Fig. 1, Table 1) with the length of 2–2.5 km were studied in each case to ensure the 4–5 repetition of main elements (stream pools and ridges) that would give a reliable information on their flora and vegetation. The sample plots were selected above the settlements, whenever possible in sites with no to intensive anthropogenic impact. The data were collected according to J. Braun-Blanquet (1964) approach. The relevés were done on the sample plot of 100 m2 placed in the most homogeneous part of the community or, in case of its smaller area, within the natural boundaries. The following scale was used for abundance estimation: r — the species is extremely rare; + — rare, small cover; 1 — the number of individuals is large, the cover is small or individuals are sparse, but the cover is large; 2 —cover of 5–25 %; 3 — 26–50 %; 4 — 51–75 %; 5 — more than 75 %. The date on water depth, transparency (on a white Secchi disk with a diameter of 30 cm), temperature and the flow rate were obtained. The soil mechanical composition and color, the degree and nature of anthropogenic impact on vegetation and river banks were quantified. Water samples for general chemical analysis were taken in the middle course of each river. Computer programs TURBOVEG and MEGATAB (Hennekens, 1996) were used for database. The syntaxonomic affiliation of phytocenoses was determined using modern literature (Bobrov, Chemeris, 2006; Vegetace..., 2011; Chepinoga, 2015; Landucci et al. 2015; Mucina et al., 2016, etc.). 36 associations and 3 communities belonging to 12 alliances, 9 orders, and 5 classes have been identified (Tables 3–14, Fig. 2–9). Such great syntaxonomic diversity is determined by the significant ecotopic variety, the variability of substrates, the wide range of water flow rates and the different water trophicity. For comparison, 26 associations, 13 variants, 2 communities were identified in the study of 50 rivers of Lithuania (Sinkyavichene, 1992); altogether 84 associations are known for the Upper Volga region as a whole (Bob­rov, Chemeris, 2006), while 45 ones were recorded previously in 130 watercourses of this region (Bobrov, 1999). Information on small river macroalgae cenoses in the study area is partially reflected in the paper published earlier (Bobrov et al., 2005).

Pre-and Post-Liming Aquatic Communities and Trout Diets

1995 ◽  
Vol 9 (3-4) ◽  
pp. 193-205 ◽  
Author(s):  
A. G. P. Milner ◽  
R. J. Aston
Keyword(s):  
Aquatic Communities

scholarly journals Relating environmental variables with aquatic community structure in an agricultural/urban coldwater stream

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Daniel T. L. Myers ◽  
Richard R. Rediske ◽  
James N. McNair ◽  
Aaron D. Parker ◽  
E. Wendy Ogilvie
Keyword(s):  
Land Use ◽  
Environmental Variables ◽  
Fish Community ◽  
Agricultural Land ◽  
Urban Land ◽  
Urban Land Use ◽  
Aquatic Communities ◽  
Natural Stream ◽  
Longitudinal Gradients ◽  
Agricultural Areas

Abstract Background Urban areas are often built along large rivers and surrounded by agricultural land. This may lead to small tributary streams that have agricultural headwaters and urbanized lower reaches. Our study objectives assessed are as follows: (1) landscape, geomorphic, and water quality variables that best explained variation in aquatic communities and their integrity in a stream system following this agricultural-to-urban land use gradient; (2) ways this land use gradient caused aquatic communities to differ from what would be expected for an idealized natural stream or other longitudinal gradients; and (3) whether the impacts of this land use gradient on aquatic communities would grow larger in a downstream direction through the agricultural and urban developments. Our study area was an impaired coldwater stream in Michigan, USA. Results Many factors structured the biological communities along the agricultural-to-urban land use gradient. Instream woody debris had the strongest relationship with EPT (Ephemeroptera, Plecoptera, and Trichoptera) abundance and richness and were most common in the lower, urbanized watershed. Fine streambed substrate had the strongest relationship with Diptera taxa and surface air breather macroinvertebrates and was dominant in agricultural headwaters. Fish community assemblage was influenced largely by stream flow and temperature regimes, while poor fish community integrity in lower urban reaches could be impacted by geomorphology and episodic urban pollution events. Scraping macroinvertebrates were most abundant in deforested, first-order agricultural headwaters, while EPT macroinvertebrate richness was the highest downstream of agricultural areas within the urban zone that had extensive forest buffers. Conclusion Environmental variables and aquatic communities would often not conform with what we would expect from an idealized natural stream. EPT richness improved downstream of agricultural areas. This shows promise for the recovery of aquatic systems using well-planned management in watersheds with this agricultural-to-urban land use pattern. Small patches of forest can be the key to conserving aquatic biodiversity in urbanized landscapes. These findings are valuable to an international audience of researchers and water resource managers who study stream systems following this common agricultural-to-urban land use gradient, the ecological communities of which may not conform with what is generally known about land use impacts to streams.

scholarly journals Counting heterotrophic nanoplanktonic protists in cultures and aquatic communities by flow cytometry

2004 ◽  
Vol 34 ◽  
pp. 263-277 ◽  
Author(s):  
JM Rose ◽  
DA Caron ◽  
ME Sieracki ◽  
N Poulton
Keyword(s):  
Flow Cytometry ◽  
Aquatic Communities

scholarly journals Periphytic algae dynamics in lentic ecosystems in the Brazilian semiarid

2016 ◽  
Vol 77 (3) ◽  
pp. 495-505 ◽  
Author(s):  
R. S. Cordeiro ◽  
J. E. L. Barbosa ◽  
G. Q. Lima Filho ◽  
L. G. Barbosa
Keyword(s):  
Aquatic Macrophytes ◽  
Soluble Reactive Phosphorus ◽  
Algal Community ◽  
Aquatic Communities ◽  
Dry Period ◽  
Rainy Period ◽  
Brazilian Semiarid ◽  
High Concentrations ◽  
Reactive Phosphorus ◽  
Reduced Density

Abstract The hydrological periods drive the structure and organization of aquatic communities in semiarid regions. We hypothesize that a decrease of the precipitation during the dry period will favor the development of the periphytic algal community, leading to higher richness and density in this period. To test this hypothesis, we investigated the changes in the periphytic algal community structure in three shallow and eutrophic ecosystems of the Brazilian semiarid. The sampling was performed between 2007 and 2010 at two-mensal intervals. The sampling of periphytic algal was performed in aquatic macrophytes and rocks. The abiotic variables were analyzed simultaneously. Dominance in diatoms, cyanobacteria and chlorophytes, respectively, was observed in two periods. In the dry period, waters were alkaline and had high concentrations of nitrate and total phosphorus associated with the highest densities of Bacillariophyceae. In the rainy period the water was warmer, oxygenated and high concentrations of ammonia and soluble reactive phosphorus with diatoms remained dominant but with reduced density, while cyanobacteria and chlorophytes increased. Overall, periphytic algal community composition no responded to changes in the hydrological periods. However, the hydrological periods altered the dynamics of periphytic algal community, supported by the alternation of the most representative classes (diatoms and cyanobacteria) between the hydrologic periods. Our data suggest that the morphometric and chemical and physical characteristics of lentic aquatic ecosystems studied were more important in the dynamics of periphytic algal community than the hydrological periods and types of substrates.

Decreasing Richness And Biomass During A Flood Pulse Observed In A Southeastern US Coastal Floodplain Following A Multi-Year, Supra-Seasonal Drought

2021 ◽  
Author(s):  
Erica L. Johnson ◽  
Erin F. Abernethy ◽  
J. Checo Colón-Gaud
Keyword(s):  
Community Composition ◽  
Climate Change Impacts ◽  
Flood Pulse ◽  
Macroinvertebrate Communities ◽  
Biological Productivity ◽  
Aquatic Communities ◽  
Functional Feeding Group ◽  
Seasonal Flooding ◽  
Southeastern Us ◽  
Feeding Group

Abstract Floodplains of the southeastern United States exhibit high biological productivity, maintained by periodic floodplain inundation as a result of seasonal flooding. To examine the relationship between biological productivity and seasonal flooding following periods of drought, we quantified aquatic macroinvertebrate communities monthly in an inundated floodplain during the annual flood pulse (December-April) in two years, one following a multi-year drought and one following a larger than average flooding event. We predicted that floodplain communities would differ in richness, biomass, and community composition between years and that differences would be driven by discharge at the main stem and organic matter availability. We collected macroinvertebrates from the floodplain of the Altamaha River, an unimpounded 6th order river in the Coastal Plain region of the southeastern US that experiences floodplain connectivity. With invertebrates identified to genus, we elucidated richness, abundance, biomass, community composition, and functional feeding group. Richness was generally higher in the drought year but decreased throughout the flood pulse, while during the flood year richness was lower and increased. Biomass decreased throughout the flood pulse following the drought year and increased during the flood year. There was a high degree of overlap in invertebrate community composition based on abundance data during both years of the study with collector gatherers being the most highly abundant functional feeding group. As climate change impacts (i.e., severe droughts) become more common, it is critical to investigate how aquatic communities are responding to increasingly unpredictable flow conditions in unimpounded and seemingly unaltered rivers.

scholarly journals Effects of clothianidin on aquatic communities: Evaluating the impacts of lethal and sublethal exposure to neonicotinoids

PLoS ONE ◽  
2017 ◽  
Vol 12 (3) ◽  
pp. e0174171 ◽  
Author(s):  
Jesse C. Miles ◽  
Jessica Hua ◽  
Maria S. Sepulveda ◽  
Christian H. Krupke ◽  
Jason T. Hoverman
Keyword(s):  
Aquatic Communities ◽  
Sublethal Exposure

scholarly journals First record of Ceratium furcoides (Dinophyta), an invasive species, in a temporary high-altitude lake in the Iron Quadrangle (MG, Southeast Brazil)

2015 ◽  
Vol 75 (1) ◽  
pp. 98-103 ◽  
Author(s):  
RA. Moreira ◽  
O. Rocha ◽  
RM. Santos ◽  
R. Laudares-Silva ◽  
ES. Dias ◽  
...  
Keyword(s):  
Invasive Species ◽  
High Altitude ◽  
First Record ◽  
Mining District ◽  
Aquatic Communities ◽  
Rainy Period ◽  
Southeast Brazil ◽  
Iron Quadrangle ◽  
Global Connections ◽  
High Altitude Lake

Dinoflagellates of the genus Ceratium are generally marine organisms, but rare occurrences in freshwater have been observed in Brazil. In this paper we are recording for the first time the presence of Ceratium furcoides, an invasive species, in a shallow, natural intermittent pool formed at a high-altitude at the southern end of the Iron Quadrangle, an iron-mining district of Minas Gerais State (Southeast Brazil). Samples were collected in October and November of 2010 (rainy period). The population density of this organism observed in Lagoa Seca (“Dry Pool”) was very low, at most 4 ind L–1. Mountain lakes are extremely vulnerable to atmospheric deposition of organisms, making them valuable witnesses both of the many forms of impact arising from human activities and of the extended global connections that facilitate the dispersion and introduction of new species over great distances. Studies on the population dynamics of C. furcoides in natural tropical systems are still rare and very recent to the brazilian scenario and hence the monitoring of its dynamics and the potential impact on aquatic communities of its becoming established are essential to an understanding of the process of bioinvasion by this species.

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