Intraspecific morphological variation in a freshwater copepod (Crustacea) in relation to geographic distribution and environment

1998 ◽  
Vol 76 (4) ◽  
pp. 751-762 ◽  
Author(s):  
Kåre Elgmork ◽  
Gunnar Halvorsen
Keyword(s):  
North America ◽  
Environmental Factors ◽  
Correlation Analysis ◽  
Morphometric Analysis ◽  
Geographic Distance ◽  
Body Proportions ◽  
Planktonic Copepod ◽  
Trophic Condition ◽  
Intraspecific Morphological Variation ◽  
Cyclops Scutifer

Intraspecific variation in morphology was studied by means of morphometric analysis in 52 populations of the freshwater planktonic copepod Cyclops scutifer G.O. Sars from Eurasia and North America. The species showed very conservative morphology over wide geographic areas and subspecies could not be established. Variations occurred irregularly, and morphologically very similar forms were found widely separated on different continents. Correlation analysis revealed that many morphological relations were correlated with environmental factors such as depth, temperature, and trophic condition. Variations in body proportions were thus related to environmental factors rather than to geographic distance.

scholarly journals Analysis of Antibiotic Resistance Genes, Environmental Factors, and Microbial Community From Aquaculture Farms in Five Provinces, China

2021 ◽  
Vol 12 ◽  
Author(s):  
Xu Cheng ◽  
Yitong Lu ◽  
Yanzhen Song ◽  
Ruifang Zhang ◽  
Xinyan ShangGuan ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Environmental Factors ◽  
Bacterial Community ◽  
Correlation Analysis ◽  
Resistance Genes ◽  
Environmental Risk ◽  
Antibiotic Resistance Genes ◽  
Community Diversity ◽  
Sediment Samples ◽  
Positive Correlation

The excessive use of antibiotics speeds up the dissemination and aggregation of antibiotic resistance genes (ARGs) in the environment. The ARGs have been regarded as a contaminant of serious environmental threats on a global scale. The constant increase in aquaculture production has led to extensive use of antibiotics as a means to prevent and treat bacterial infections; there is a universal concern about the environmental risk of ARGs in the aquaculture environment. In this study, a survey was conducted to evaluate the abundance and distributions of 10 ARGs, bacterial community, and environmental factors in sediment samples from aquatic farms distributed in Anhui (AP1, AP2, and AP3), Fujian (FP1, FP2, and FP3), Guangxi (GP1, GP2, and GP3), Hainan (HP1, HP2, and HP3), and Shaanxi (SP1, SP2, and SP3) Province in China. The results showed that the relative abundance of total ARGs was higher in AP1, AP2, AP3, FP3, GP3, HP1, HP2, and HP3 than that in FP1, FP2, GP1, GP2, SP1, SP2, and SP3. The sul1 and tetW genes of all sediment samples had the highest abundance. The class 1 integron (intl1) was detected in all samples, and the result of Pearson correlation analysis showed that the intl1 has a positive correlation with the sul1, sul2, sul3, blaOXA, qnrS, tetM, tetQ, and tetW genes. Correlation analysis of the bacterial community diversity and environmental factors showed that the Ca2+ concentration has a negative correlation with richness and diversity of the bacterial community in these samples. Of the identified bacterial community, Proteobacteria, Firmicutes, Chloroflexi, and Bacteroidota were the predominant phyla in these samples. Redundancy analysis showed that environmental factors (TN, TP, Cl–, and Ca2+) have a positive correlation with the bacterial community (AP1, GP1, GP2, GP3, SP1, SP2, and SP3), and the abundance of ARGs (sul1, tetW, qnrS, and intl1) has a positive correlation with the bacterial community (AP2, AP3, HP1, HP2, and HP3). Based on the network analysis, the ARGs (sul1, sul2, blaCMY, blaOXA, qnrS, tetW, tetQ, tetM, and intl1) were found to co-occur with bacterial taxa from the phyla Chloroflexi, Euryarchaeota, Firmicutes, Halobacterota, and Proteobacteria. In conclusion, this study provides an important reference for understanding the environmental risk associated with aquaculture activities in China.

Study on the Relationship between Population Density of Noctiluca scintillans and Environmental Factors in the Coastal Waters of Qinhuangdao

2014 ◽  
Vol 1010-1012 ◽  
pp. 635-638
Author(s):  
Yan Juan Xi ◽  
Zhen Liang Zhao ◽  
Chun Long Zhao ◽  
Yan Qin Xi ◽  
Li Yan ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Population Density ◽  
Correlation Analysis ◽  
Dissolved Oxygen ◽  
Linear Correlation ◽  
Coastal Waters ◽  
Ammonia Nitrogen ◽  
Noctiluca Scintillans ◽  
Nitrite Nitrate ◽  
The Relationship

Based on the environmental survey data in off-shore of Qin Huangdao from May to June 2011,correlation analysis was made between population density of Noctiluca scintillans and environmental factors. The results indicates that population density of Noctiluca scintillans does not exist linear correlation with nitrite, nitrate, ammonia, nitrogen, phosphate,dissolved oxygen and PH ,it is positive correlation with temperature and silicate noctiluca and negatively correlation with transparency and salinity.

Assessing groundwater management sustainability of coastal cities by utilizing the City Blueprint Approach 

2021 ◽  
Author(s):  
Khawon Lee ◽  
Sun Woo Chang ◽  
Jeryang Park
Keyword(s):  
Water Management ◽  
Environmental Factors ◽  
Correlation Analysis ◽  
Groundwater Quality ◽  
Groundwater Management ◽  
Coastal Regions ◽  
Sustainable Groundwater Management ◽  
Coastal Cities ◽  
Major Factors ◽  
The City

<p>    Groundwater is the largest freshwater resource available on Earth, and many coastal regions are depending on groundwater as a primary freshwater source. For example, in Busan and Incheon, two of the largest coastal cities in South Korea, 5.7% and 7.0% of freshwater uses are from groundwater while only 1.8% is from groundwater in Seoul, the capital of the country. Globally, groundwater availability is diminishing primarily by population increase, and especially in coastal regions, this problem is exacerbated by overexploitation and seawater intrusion, which causes groundwater contamination and further reduces its availability. Here, we view the groundwater system and its management for sustainability as a complex problem that is associated with various social, economic, and environmental factors. By adopting the City Blueprint Approach (CBA), which has been used extensively for assessing the sustainability of integrated water management of numerous cities on the globe, we identify water management factors that potentially have direct and indirect links and feedbacks with groundwater variables. We selected Busan and Incheon as case studies for coastal cities that are facing the risk of groundwater salinization by seawater intrusion. This study aims to 1) assess City Blueprint (CB) of selected coastal cities, 2) identify major factors for coastal groundwater management through correlation analysis, and 3) suggest management options regarding identified factors for sustainable groundwater management of the study areas. Our results on CB indicate that the groundwater quality and quantity of the selected cities are currently in ‘good’ status. Also, from the correlation analysis, we identified heat risk and freshwater scarcity as the major factors that potentially can affect groundwater quantity. For groundwater quality, the factors of voice and accountability, regulatory quality, and rule of law and control of corruption, most of which had not been explicitly considered for groundwater management, were identified as the major factors. Some of these factors were assessed from ‘little concern’ to ‘very concern’ for both cities. These results indicate that, regarding the linkages between groundwater variables and other factors in concern, more actions beyond environmental factors should be taken for sustainable groundwater management. This study helps to understand how non-conventional factors could contribute to coastal groundwater, and can provide extensive options for sustainable groundwater management.</p><p> </p><p><strong>Acknowledgement</strong>: This research was supported by the Development program of Minimizing of Climate Change Impact Technology through the National Research Foundation of Korea (NRF), funded by the Korean government (Ministry of Science and ICT) (NRF-2020M3H5A1080775).</p>

Epidemiology of autism

2020 ◽  
pp. 260-269
Author(s):  
Charles R. Newton
Keyword(s):  
Risk Factors ◽  
North America ◽  
Environmental Factors ◽  
Genetic Susceptibility ◽  
Growth Retardation ◽  
Financial Burden ◽  
Premature Mortality ◽  
Educational Systems ◽  
Postnatal Exposure ◽  
Apparent Increase

The epidemiology of autism has been recently highlighted with the apparent increase in the prevalence of autism in North America and Europe, and controversy about the association of autism with vaccines. The overall prevalence is about 1%, and the apparent increase is probably due to greater awareness of the diagnosis, more facilities for diagnosis, and changes in the criteria for the diagnosis. Autism is likely to arise from an interaction between genetic susceptibility and environmental factors. Identified risk factors include maternal infection, prematurity, intrauterine growth retardation, and perinatal and postnatal exposure to toxins and infections. There is no evidence that autism is associated with vaccination. Autism is associated with premature mortality and has considerable financial burden on national health and educational systems.

scholarly journals Regional epigenetic variation in asexual snail populations among urban and rural lakes

2019 ◽  
Vol 5 (4) ◽  
Author(s):  
Jennifer L M Thorson ◽  
Mark Smithson ◽  
Ingrid Sadler-Riggleman ◽  
Daniel Beck ◽  
Mark Dybdahl ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Environmental Factors ◽  
Geographic Distance ◽  
Dispersal Distance ◽  
Population History ◽  
Northwest Pacific ◽  
Sample Population ◽  
Epigenetic Variation ◽  
Urban Lake ◽  
Urban Lakes

Abstract Epigenetic variation has the potential to influence environmentally dependent development and contribute to phenotypic responses to local environments. Environmental epigenetic studies of sexual organisms confirm the capacity to respond through epigenetic variation. An epigenetic response could be even more important in a population when genetic variation is lacking. A previous study of an asexual snail, Potamopyrgus antipodarum, demonstrated that different populations derived from a single clonal lineage differed in both shell phenotype and methylation signature when comparing lake versus river populations. Here, we examine methylation variation among lakes that differ in environmental disturbance and pollution histories. Snails were collected from a more pristine rural Lake 1 (Lake Lytle), and two urban lakes, Lake 2 (Capitol Lake) and Lake 3 (Lake Washington) on the Northwest Pacific coast. DNA methylation was assessed for each sample population using methylated DNA immunoprecipitation, MeDIP, followed by next-generation sequencing. The differential DNA methylation regions (DMRs) identified among the different lake comparisons suggested a higher number of DMRs and variation between rural Lake 1 and one urban Lake 2, and between the two urban Lakes 2 and 3, but limited variation between the rural Lake 1 and urban Lake 3. DMR genomic characteristics and gene associations were investigated. The presence of site-specific differences between each of these lake populations suggest an epigenetic response to varied environmental factors. The results do not support an effect of geographic distance in these populations. The role of dispersal distance among lakes, population history, environmental pollution and stably inherited methylation versus environmentally triggered methylation in producing the observed epigenetic variation are discussed. Observations support the proposal that epigenetic alterations may associate with phenotypic variation and environmental factors and history of the different lakes.

scholarly journals The biology of Canadian weeds. 131. Polygonum aviculare L.

2005 ◽  
Vol 85 (2) ◽  
pp. 481-506 ◽  
Author(s):  
Mihai Costea ◽  
François J. Tardif
Keyword(s):  
Phenotypic Plasticity ◽  
North America ◽  
Environmental Factors ◽  
Genetic Variability ◽  
Key Words ◽  
Personal Data ◽  
Biological Information ◽  
Cultivated Plants ◽  
Polygonum Aviculare ◽  
Genetic And Environmental Factors

A review and assessment of biological information as well as personal data are provided for Polygonum aviculare in Canada. The species has been revised taxonomically and the six subspecies that occur in Canada are presented. Three of the subspecies, P. aviculare subsp. aviculare, P. aviculare subsp. neglectum and P. aviculare subsp. depressum are weeds introduced to Canada from Europe. A fourth subspecies, P. aviculare subsp. buxiforme is apparently native to North America. The geographical distribution of the latter four subspecies is very wide. Plants exhibit a high phenotypic plasticity and genetic variability, and they easily adapt to a multitude of agrestal and ruderal habitats. The seeds have a variable dormancy and polymorphic germination as a result of heterocarpy, genetic and environmental factors. In other areas (Europe), the species has developed resistance to triazines. Plants are hosts to nematodes, viruses, and fungi that also affect cultivated plants. Key words: POLAV, ecology, distribution, taxonomy

scholarly journals Enviromental factors as the elements determing the development of floating homes

2021 ◽  
pp. 41-51
Author(s):  
Emilia MISZEWSKA ◽  
Maciej NIEDOSTATKIEWICZ ◽  
Radosław WIŚNIEWSKI
Keyword(s):  
Climate Change ◽  
North America ◽  
Environmental Factors ◽  
Population Density ◽  
Significant Role ◽  
Western Europe ◽  
The State ◽  
Land Prices ◽  
The Impact

The popularity of Floating Homes in Western Europe and North America is noticeable. The interest in these facilities in Poland is also constantly growing. The popularity of Floating Homes is due to climate change, rising land prices and population density in city centers. However, environmental factors play a significant role in their development. The publication presents the results of research on the impact of environmental factors on the development of Floating Homes in Poland. As part of the research, the most important environmental factors were identified and then, using the State of the Surroundings Scenarios (SSS) method, an initial scenario of their development was developed. The most probable scenario was developed, the purpose of which was to identify the most favorable factors - strengths and unfavorable factors - weaknesses responsible for the development opportunities of Floating Homes in Poland. Additionally, a surprise scenario was prepared, which indicated factors that may unexpectedly accelerate the development of Floating Homes in Poland or slow it down.

Sign in / Sign up

Export Citation Format

Share Document