The effect of environmental factors on the mayfly communities of headwater streams in the Pieniny Mountains (West Carpathians)

AbstractA study of the species composition of mayfly communities in connection with environmental parameters was made in headwater streams of the Pieniny Mts. The rhithral zone is inhabited maximally by 19 mayfly species. In most of the streams studied the mayfly communities were found to be similar, however the vertical zonation which reflected human impact was visible (NMDS analysis). The main factors responsible for mayfly communities at all the sites studied were stream regulation and organic pollution, followed by type of bottom substrate (pebble and gravel), riparian vegetation (shrubs), pH and water temperature. At undisturbed sites the most important factors were pH, substrate type, distance from the source, current velocity and riparian vegetation (CCA analysis). Analysis of mayfly communities and environmental characteristics in different seasons showed that occurrence of mayfly species varied substantially depending on the season. Only in early spring and autumn do mayfly communities occur which are dependent on many environmental factors, the most significant of which are substrate type, phosphate, distance from source and altitude (CCA analysis).

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Zooplankton communities in the Drake Passage through environmental boundaries: a snapshot of 2010, early spring

PeerJ ◽

10.7717/peerj.7994 ◽

2019 ◽

Vol 7 ◽

pp. e7994

Author(s):

Andrey A. Vedenin ◽

Eteri I. Musaeva ◽

Daria N. Zasko ◽

Alexander L. Vereshchaka

Keyword(s):

Spatial Distribution ◽

Environmental Factors ◽

Chlorophyll Concentration ◽

Environmental Parameters ◽

Drake Passage ◽

Early Spring ◽

Zooplankton Abundance ◽

Depth Range ◽

Zooplankton Structure ◽

Zooplankton Communities

Background Spatial distribution of zooplankton communities influenced by various environmental factors is always important for understanding pelagic ecosystems. The area of the Drake Passage (Southern Ocean) is of particular interest owing to the high spatial and temporal variability of hydrological parameters affecting marine fauna. This study provides a survey of zooplankton composition and spatial distribution along a transect in the Drake Passage sampled during the 31th Cruise of RV “Akademik Sergey Vavilov” in November, 2010. The main aim was to trace the main regularities in spatial zooplankton structure and its relationships with the environmental parameters. Methodology A total of 43 vertical hauls from the surface to 1,000 m depth were made at 13 stations using the Juday plankton net. 60 taxa were recorded, abundance and biomass of each were assessed. Environmental parameters including temperature, salinity, depth, horizontal distance between stations and surface chlorophyll concentration were tested as environmental factors possibly explaining plankton distribution. Results Higher zooplankton abundance and biomass with lower diversity were observed near the Polar Front. Cluster analysis revealed five different groups of zooplankton samples, four of which were arranged mostly by depth. Along the transect within the 1,000 m depth range, the qualitative taxonomical composition differed significantly with depth and to some extent differed also among horizontal hydrological regimes, while the quantitative structure of the communities (abundance of taxa) was mainly determined by depth. Plankton assemblages within the upper 300-m layer depended on hydrological fronts. Abundance of dominant taxa as well as total zooplankton abundance showed a clear correlation with depth, salinity and surface chlorophyll concentration. Some taxa also showed correlations with temperature and latitude. Between the stations the similarity in zooplankton structure was clearly dependent on the distance among them which indicates an importance of latitudinal gradient. Surface chlorophyll concentration was not correlated with zooplankton biomass, which can be explained by the uncompleted seasonal migrations of zooplankton from deeper waters in early spring.

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Predicting the Presence of Leptospires in Rodents from Environmental Indicators Opens Up Opportunities for Environmental Monitoring of Human Leptospirosis

Remote Sensing ◽

10.3390/rs13020325 ◽

2021 ◽

Vol 13 (2) ◽

pp. 325

Author(s):

Leon Biscornet ◽

Christophe Révillion ◽

Sylvaine Jégo ◽

Erwan Lagadec ◽

Yann Gomard ◽

...

Keyword(s):

Infectious Disease ◽

Environmental Factors ◽

Control Strategies ◽

Sampling Site ◽

Rattus Rattus ◽

Environmental Parameters ◽

Environmental Indicators ◽

Small Island ◽

Urban Landscapes ◽

Infection Prevalence

Leptospirosis, an environmental infectious disease of bacterial origin, is the infectious disease with the highest associated mortality in Seychelles. In small island territories, the occurrence of the disease is spatially heterogeneous and a better understanding of the environmental factors that contribute to the presence of the bacteria would help implement targeted control. The present study aimed at identifying the main environmental parameters correlated with animal reservoirs distribution and Leptospira infection in order to delineate habitats with highest prevalence. We used a previously published dataset produced from a large collection of rodents trapped during the dry and wet seasons in most habitats of Mahé, the main island of Seychelles. A land use/land cover analysis was realized in order to describe the various environments using SPOT-5 images by remote sensing (object-based image analysis). At each sampling site, landscape indices were calculated and combined with other geographical parameters together with rainfall records to be used in a multivariate statistical analysis. Several environmental factors were found to be associated with the carriage of leptospires in Rattus rattus and Rattus norvegicus, namely low elevations, fragmented landscapes, the proximity of urbanized areas, an increased distance from forests and, above all, increased precipitation in the three months preceding trapping. The analysis indicated that Leptospira renal carriage could be predicted using the species identification and a description of landscape fragmentation and rainfall, with infection prevalence being positively correlated with these two environmental variables. This model may help decision makers in implementing policies affecting urban landscapes and/or in balancing conservation efforts when designing pest control strategies that should also aim at reducing human contact with Leptospira-laden rats while limiting their impact on the autochthonous fauna.

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Risk and Environmental Factors Associated with the Presence of Canine Parvovirus Type 2 in Diarrheic Dogs from Thessaly, Central Greece

Pathogens ◽

10.3390/pathogens10050590 ◽

2021 ◽

Vol 10 (5) ◽

pp. 590

Author(s):

Maria Kantere ◽

Labrini V. Athanasiou ◽

Alexios Giannakopoulos ◽

Vassilis Skampardonis ◽

Marina Sofia ◽

...

Keyword(s):

Environmental Factors ◽

Clinical Symptoms ◽

Gastrointestinal Disease ◽

Environmental Parameters ◽

Canine Parvovirus ◽

Geographical Information ◽

Factors Associated ◽

Working Dogs ◽

Canine Parvovirus Type 2

Canine parvovirus type 2 (CPV-2) primarily infects dogs, which are the main host reservoir, causing severe gastrointestinal disease associated with immunosuppression. The present study was conducted in Thessaly, Greece and aimed to identify risk and environmental factors associated with CPV-2 infection in diarrheic dogs. Fecal samples were collected from 116 dogs presenting diarrhea and were tested by polymerase chain reaction (PCR) for the presence of CPV-2 DNA. Supplementary data regarding clinical symptoms, individual features, management factors and medical history were also gathered for each animal during clinical evaluation. Sixty-eight diarrheic dogs were found to be positive for the virus DNA in their feces. Statistical analysis revealed that CPV-2 DNA was less likely to be detected in senior dogs, while working dogs, namely hounds and shepherds, had higher odds to be positive for the virus. Livestock density and land uses, specifically the categories of discontinuous urban fabric and of human population density, were identified as significant environmental parameters associated with CPV-2 infection by using Geographical Information System (GIS) together with the Ecological Niche Model (ENM). This is the first description of the environmental variables associated with the presence of CPV-2 DNA in dogs’ feces in Greece.

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Relationships between Environmental Factors and Pathogenic Vibrios in the Northern Gulf of Mexico

Applied and Environmental Microbiology ◽

10.1128/aem.00697-10 ◽

2010 ◽

Vol 76 (21) ◽

pp. 7076-7084 ◽

Cited By ~ 119

Author(s):

C. N. Johnson ◽

A. R. Flowers ◽

N. F. Noriea ◽

A. M. Zimmerman ◽

J. C. Bowers ◽

...

Keyword(s):

Environmental Factors ◽

Water Column ◽

Vibrio Vulnificus ◽

Environmental Parameters ◽

Sampling Period ◽

Pathogenicity Factor ◽

Hemolysin Gene ◽

Thermostable Direct Hemolysin ◽

Pathogenic Vibrios ◽

Abundance And Distribution

ABSTRACT Although autochthonous vibrio densities are known to be influenced by water temperature and salinity, little is understood about other environmental factors associated with their abundance and distribution. Densities of culturable Vibrio vulnificus containing vvh (V. vulnificus hemolysin gene) and V. parahaemolyticus containing tlh (thermolabile hemolysin gene, ubiquitous in V. parahaemolyticus), tdh (thermostable direct hemolysin gene, V. parahaemolyticus pathogenicity factor), and trh (tdh-related hemolysin gene, V. parahaemolyticus pathogenicity factor) were measured in coastal waters of Mississippi and Alabama. Over a 19-month sampling period, vibrio densities in water, oysters, and sediment varied significantly with sea surface temperature (SST). On average, tdh-to-tlh ratios were significantly higher than trh-to-tlh ratios in water and oysters but not in sediment. Although tlh densities were lower than vvh densities in water and in oysters, the opposite was true in sediment. Regression analysis indicated that SST had a significant association with vvh and tlh densities in water and oysters, while salinity was significantly related to vibrio densities in the water column. Chlorophyll a levels in the water were correlated significantly with vvh in sediment and oysters and with pathogenic V. parahaemolyticus (tdh and trh) in the water column. Furthermore, turbidity was a significant predictor of V. parahaemolyticus density in all sample types (water, oyster, and sediment), and its role in predicting the risk of V. parahaemolyticus illness may be more important than previously realized. This study identified (i) culturable vibrios in winter sediment samples, (ii) niche-based differences in the abundance of vibrios, and (iii) predictive signatures resulting from correlations between environmental parameters and vibrio densities.

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The impact of environmental variables on the spread of COVID-19 in the Republic of Korea

Scientific Reports ◽

10.1038/s41598-021-85493-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yong Kwan Lim ◽

Oh Joo Kweon ◽

Hye Ryoun Kim ◽

Tae-Hyoung Kim ◽

Mi-Kyung Lee

Keyword(s):

Environmental Factors ◽

Virus Disease ◽

Environmental Parameters ◽

Environmental Data ◽

Republic Of Korea ◽

Metropolitan Region ◽

Health Concern ◽

Ozone Level ◽

The Republic ◽

The Impact

AbstractCorona virus disease 2019 (COVID-19) has been declared a global pandemic and is a major public health concern worldwide. In this study, we aimed to determine the role of environmental factors, such as climate and air pollutants, in the transmission of COVID-19 in the Republic of Korea. We collected epidemiological and environmental data from two regions of the Republic of Korea, namely Seoul metropolitan region (SMR) and Daegu-Gyeongbuk region (DGR) from February 2020 to July 2020. The data was then analyzed to identify correlations between each environmental factor with confirmed daily COVID-19 cases. Among the various environmental parameters, the duration of sunshine and ozone level were found to positively correlate with COVID-19 cases in both regions. However, the association of temperature variables with COVID-19 transmission revealed contradictory results when comparing the data from SMR and DGR. Moreover, statistical bias may have arisen due to an extensive epidemiological investigation and altered socio-behaviors that occurred in response to a COVID-19 outbreak. Nevertheless, our results suggest that various environmental factors may play a role in COVID-19 transmission.

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Denitrifying bacterial communities in surface-flow constructed wetlands during different seasons: characteristics and relationships with environment factors

Scientific Reports ◽

10.1038/s41598-021-82438-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jia-ming Wei ◽

Li-juan Cui ◽

Wei Li ◽

Yun-mei Ping ◽

Wan Li

Keyword(s):

Environmental Factors ◽

High Throughput Sequencing ◽

Bacterial Abundance ◽

Flow Direction ◽

Denitrifying Bacteria ◽

Surface Flow ◽

Strongly Correlated ◽

Community Structures ◽

Oxidation Reduction ◽

Different Seasons

AbstractDenitrification is an important part of the nitrogen cycle and the key step to removal of nitrogen in surface-flow wetlands. In this study, we explored space–time analysis with high-throughput sequencing to elucidate the relationships between denitrifying bacteria community structures and environmental factors during different seasons. Our results showed that along the flow direction of different processing units, there were dynamic changes in physical and chemical indicators. The bacterial abundance indexes (ACEs) in May, August, and October were 686.8, 686.8, and 996.2, respectively, whereas the Shannon-Weiner indexes were 3.718, 4.303, and 4.432, respectively. Along the flow direction, the denitrifying bacterial abundance initially increased and then decreased subsequently during the same months, although diversity tended to increase. The abundance showed similar changes during the different months. Surface flow wetlands mainly contained the following denitrifying bacteria genus: unclassified Bacteria (37.12%), unclassified Proteobacteria (18.16%), Dechloromonas (16.21%), unranked environmental samples (12.51%), unclassified Betaproteobacteria (9.73%), unclassified Rhodocyclaceae (2.14%), and Rhodanobacter (1.51%). During different seasons, the same unit showed alternating changes, and during the same season, bacterial community structures were influenced by the second genus proportion in different processing units. ACEs were strongly correlated with temperature, dissolved oxygen, and pH. Bacterial diversity was strongly correlated with temperature, electrical conductivity, pH, and oxidation reduction potential. Denitrifying bacteria are greatly affected by environmental factors such as temperature and pH.

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Effects of environmental factors and predation on benthic communities in headwater streams

Aquatic Sciences ◽

10.1007/s00027-010-0145-8 ◽

2010 ◽

Vol 72 (4) ◽

pp. 419-429 ◽

Cited By ~ 18

Author(s):

Graciela G. Nicola ◽

Ana Almodóvar ◽

Benigno Elvira

Keyword(s):

Environmental Factors ◽

Headwater Streams ◽

Benthic Communities

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Proximate Analysis of British Columbia Herring in Relation to Season and Condition Factor

Journal of the Fisheries Research Board of Canada ◽

10.1139/f38-049 ◽

1939 ◽

Vol 4b (5) ◽

pp. 478-490

Author(s):

John Lawson Hart ◽

Albert L. Tester ◽

Desmond Beall ◽

John P. Tully

Keyword(s):

British Columbia ◽

Oil Content ◽

Condition Factor ◽

Calorific Value ◽

Proximate Analysis ◽

Early Spring ◽

Different Seasons ◽

Spawning Time ◽

Average Condition ◽

The Individual

Analysis by standard methods of samples of Clupea pallasii from different seasons and localities in British Columbia showed the following ranges in composition: water, 64.2 to 80.2%; oil, 4.1 to 19.4%; protein, 10.1 to 16.8%; ash, 1.9 to 2.8%. Oil content is highest in summer, declines during the fall and winter, and falls to a minimum after spawning time in early spring. There is an accompanying decline in the weight of the fish. Herring are highly variable in calorific value (2.41 to 0.94 Calories per gram). Potential oil yields on reduction as high as 30 gallons per ton are indicated with a minimum of 7 gallons per ton. Average condition factors for samples were determined by averaging the individual condition factors obtained from [Formula: see text], when C is the condition factor, W is weight in grams, L is length in millimetres, and 3.26 is the exponent in the empirically fitted equation W = CLn. This condition factor was found to be positively correlated with oil content and to follow in general the same seasonal trend.

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Floristic study and assessment of the environmental factors governing the distribution of riparian plants in the Zat sub-Basin: Tensift Watershed, Morocco

Journal of Animal & Plant Sciences ◽

10.35759/janmplsci.v45-2.3 ◽

2020 ◽

Vol 45 (2) ◽

pp. 7900-7915

Author(s):

Mostakim Lahcen ◽

Fetnassi Nidal ◽

Ghamizi Mohamed

Keyword(s):

Environmental Factors ◽

Pearson Correlation ◽

Ecological Status ◽

Environmental Parameters ◽

Quality Parameters ◽

Phosphorus Concentration ◽

Factors Affecting ◽

Riparian Plants ◽

Emergent Plants ◽

Significant Difference

Measuring the phytodiversity and determining environmental factors affecting the abundance and distribution of riparian plants of Zat sub-basin in Morocco were carried out in this study. A hypothesis was tested whether there is any statistically significant difference in environmental parameters and plants communities among the Zat River and its tributaries. For this purpose, water quality parameters such as temperature, pH, salinity, electrical conductivity, Dissolved Oxygen, nitrate and phosphorus concentration, and riparian plants diversity were estimated at 17 stations along the Zat River and its tributaries during the periods (2018 and 2019). The Canonical Correspondence Analysis (CCA) and Pearson correlation were preformed to assess the relationship between environmental parameters, and the distribution and abundance of riparian plants inventoried. The presence of 113 species was recorded, distributed between 43 families and 97 genera, 9 of which were floating-leaved, 24 submerged, and 80 emergent plants. The rare and threatened species inventoried were represented by 7 taxa, whereas 6 species are reported as endemic. Raunkiaer classification showed a dominance of therophytes (38.39%) over the other groups. According to CCA, the abiotic parameters (DO, elevation, salinity and nitrate concentration) were statistically significant parameters governing the distribution and abundance of the riparian plants inventoried. The results obtained reveal the state of the riparian vegetation in the Zat subBasin, therefore we can consider them as a reliable component for the assessment of the ecological status of the aquatic environment.

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Spatial pattern of riparian plants along stream order among mountain rivers in China

Journal of Water and Climate Change ◽

10.2166/wcc.2018.047 ◽

2018 ◽

Vol 9 (2) ◽

pp. 322-330

Author(s):

Rong Sun ◽

Xiaojie Luo ◽

Xiangyu Meng ◽

Yan Wang

Keyword(s):

Species Richness ◽

Environmental Factors ◽

Tree Species ◽

Riparian Vegetation ◽

Stream Order ◽

River Continuum ◽

Riparian Plants ◽

Tree Species Richness ◽

Riparian Species ◽

Significant Difference

Abstract The streams in a watershed form a hierarchical network system. From the perspective of the river continuum, this classification system is the result of gradual increase in traffic. This study analyzed the riparian species richness, diversity and environmental factors along a six-order hierarchical mountain river in the Donghe watershed, China. A total of 34 sampling sites were sampled to study the spatial distribution of riparian plants among different stream orders. The results showed: Environmental factors among stream orders had significant differences. Among stream order, species richness showed remarkable differences. The species richness rose firstly and dropped afterwards except for tree species richness; tree species richness decreased while stream order increased. The same is true for shrub quadrat species richness. Shannon-Wiener diversity, Simpson dominance and Pielou uniformity showed significant difference among stream orders; Shannon-Wiener diversity rose firstly then dropped afterwards. For integrated environmental factors and community characteristics, we found the changes of stream orders had a significant impact on riparian habitats and riparian vegetation. Further analysis showed that riparian vegetation experienced different types and degrees of disturbance in different stream orders. This meant that a hierarchical management strategy should be applied to riparian vegetation management.

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