scholarly journals Invasion of non-indigenous suckermouth armoured catfish of the genus Pterygoplichthys (Loricariidae) in the East Kolkata Wetlands: Stakeholders’ perception

2019 ◽  
Vol 66 (2) ◽  
Author(s):  
Ajmal Hussan ◽  
J.K. Sundaray ◽  
R.N. Mandal ◽  
Farhana Hoque ◽  
Arabinda Das ◽  
...  
Keyword(s):  
Seasonal Pattern ◽  
Nutrient Release ◽  
Sewage Water ◽  
Population Increase ◽  
East Kolkata Wetlands ◽  
Rapid Spread ◽  
Spread Area ◽  
Somatic Index ◽  
Armoured Catfish ◽  
Financial Losses

Rapid spread and population increase of suckermouth armoured catfishes belonging to the genus Pterygoplichthys(Loricariidae) in the East Kolkata Wetlands (EKW) in recent times is of increasing concern, because of the notable possibility that these non-native catfishes are adversely affecting fish germplasm and commercial fishery of this unique ecosystem. To study the present status of these loricariids and the invasion and impact dynamics in EKW ecosystems, field survey was conducted over a water spread area of 670 ha, comprising 120 fishermen (N2 = 120) of 30 farms (N1 = 30),  between February and October, 2017 through a pre-tested, open-ended structured schedule. A total of 943 specimens of Pterygoplichthysspp. were collected and analysed for abundance, length-weight parameters, gonado-somatic index and relative fecundity.  Pterygoplichthysspp. occurred at 29 (97%) of 30 surveyed farms and approximately 70% of the farm owners perceived that these fishes posed moderate to serious economic impact. Fish production cutback, small indigenous fish (particularly,Puntius spp.) depredation and bottom structure alteration are among the major negatives perceived; a positive note in terms of soil-bound nutrient release was reported by a few fishermen (1%). Channel through which sewage water intake occurred by gravitation has been perceived to be the main route of entry (77%), with significantly higher abundance around the periphery of the pond. Almost 80% respondents perceived an increased occurrence of these fishes over the last four years, with seasonal pattern of abundance. While culling of suckermouthafter harvest was the most common method adopted to reduce population, multi-layer screening in the inlet of sewage water into pond is perceived as most sought solution for control. Average direct and indirect financial losses due to Pterygoplichthys spp. in EKW was calculated as`0.092 lakh ha-1yr-1, which points towards mounting pressure of loricariids in already dwindling economics and biodiversity of EKW.

scholarly journals Comparative Limnological Studies in Mysuru City

2016 ◽  
Vol 4 (3) ◽  
pp. 506
Author(s):  
Shiva Kumar D ◽  
Abhilash M R ◽  
Nagaraju A ◽  
Smitha N ◽  
Shivalingaiah C
Keyword(s):  
Human Activities ◽  
Anthropogenic Activities ◽  
Dynamic Balance ◽  
Water Security ◽  
Chemical Characteristic ◽  
Water Shortage ◽  
Sewage Water ◽  
Population Increase ◽  
Dynamic State ◽  
Water Shortages

<div><p><em>Water security is emerging as an important and imperative issue for India. Many Indian cities are experiencing moderate to severe water shortages due to understood effects of industrialization and urbanization. These shortages would be further provoked by population stress and irrigation requirements that are major factors related to water insecurity. Around 1.2 billion people, or almost one-fifth of the world's population, live in areas of physical scarcity and 500 million people are approaching this situation. Another 1.6 billion people or almost one quarter of the world's population, are facing economic water shortage. Water use is growing at more than twice the rate of population increase in the last century. The water bodies, rivers, lakes, dams and estuaries are continuously subject to dynamic state of change with respect to the geological age and geochemical characteristics. The dynamic balance in the aquatic ecosystem is upset by human activities, resulting in pollution which is manifested dramatically as fish kill, offensive taste, odor, color, and unchecked aquatic weeds. Consequences of such human activities and discharge of sewage water makes the existence of the lakes more vulnerable. It is the prime necessary to take immediate remedial action to prevent all anthropogenic activities in the studied lakes or else the lakes will become biologically barren and will be lost forever. In the present study an attempt was made to know the physical, chemical, characteristic of lake water of selected lakes of Mysuru city. </em></p></div>

scholarly journals Cyanobacterial occurrence and detection of microcystins and saxitoxins in reservoirs of the Brazilian semi-arid

2015 ◽  
Vol 27 (1) ◽  
pp. 78-92 ◽  
Author(s):  
Jessica Roberts Fonseca ◽  
Pryscila Cynara Soares Vieira ◽  
Paula Kujbida ◽  
Ivaneide Alves Soares da Costa
Keyword(s):  
Public Health ◽  
Seasonal Pattern ◽  
Water Quality Monitoring ◽  
Quality Monitoring ◽  
Environmental Damage ◽  
Human Consumption ◽  
Rapid Spread ◽  
Clear Seasonal Pattern ◽  
San Rafael ◽  
Semi Arid

Aim:The rapid spread of cyanobacteria in water sources and reservoirs has caused serious environmental damage and public health problems, and consists in a problem that challenges the institutions responsible for providing water to the population. In this study, the quantification of microcystin, saxitoxins and cyanobacteria levels was performed over 3 years in the semi-arid reservoirs of Rio Grande do Norte (Brazil). In addition, we analyzed the seasonal distribution of cyanotoxins and the percentage of cyanobacteria and cyanotoxins which were above the limit established by Brazilian law.MethodsThe study was conducted between 2009 and 2011 in four dams with six sites: Armando Ribeiro Gonçalves (ARG) in Itajá, San Rafael (SR) and Jucurutu; Passagem das Traíras (PT); Itans and Gargalheiras (GARG). Cyanobacteria presence were quantified and identified and the presence of microcystins (MCYs) and saxitoxins (STXs) was investigated by ELISA.ResultsThe densities of cyanobacteria were found to be above the permitted in 76% of cases. The ELISA results showed that of the 128 samples analyzed, 27% were above the maximum allowed by the Brazilian Ministry of Health Order 2914/2011. A seasonal pattern for the presence of MCYs was found (0.00227 to 24.1954 µg.L–1), with the highest values in the rainy season. There was no clear seasonal pattern for STXs (0.003 to 0.766 µg.L–1).ConclusionsThis study showed the importance of establishing a water quality monitoring for human consumption and its potability standards since the concentration of MCYs in some samples was above the maximum limit allowed by Brazilian law, thus posing a risk to public health since the conventional water treatment is not able to eliminate these potent hepatotoxins.

scholarly journals Litterfall, Decomposition and Nutrient Release in Sacred Forests of Western Odisha, India.

2020 ◽  
Author(s):  
Antaryami Pradhan ◽  
Niranjan Behera
Keyword(s):  
Nutrient Cycling ◽  
Ecosystem Functioning ◽  
Seasonal Pattern ◽  
Terrestrial Ecosystem ◽  
Nutrient Release ◽  
Agricultural Landscapes ◽  
Ecosystem Functions ◽  
Litter Bag ◽  
Significant Difference ◽  
Sacred Forests

Abstract Background Recognizing that litterfall and decomposition are key ecosystem functions for ecosystem stability in a terrestrial ecosystem, litterfall and decomposition in four sacred forests were studied from western part of Odisha. The present study focuses on the detailed aspects of litter dynamics, decomposition and consequent release of nutrients to the forest floor. The results obtained in this study will be beneficial in understanding the ecosystem functioning associated with nutrient cycling, which helps in determining possible management strategies for optimization of ecosystem functioning and productivity of these sacred forests. Results Litterfall and standing litter showed a seasonal pattern with most of the litter accumulated during the dry seasons and lowest in the rainy season. However, no significant difference was observed between the litterfall patterns of the sacred forests. The annual turnover rate (KL) was found to be in the range of 3.59/yr to 4.22/yr in studied sacred forests. The litter decomposition study was performed by litter bag technique and almost 95% of mass loss was observed within a period of 6 months. Such fast decomposition leads to faster rate of nutrient release across the sites. The studied elements can be set in the following order as regards to their return to the topsoil during decomposition in the order of K (Potassium) > N (Nitrogen) > P (Phosphorus). The approximate amount of nutrient released to the forest soil is quantified in the range of 184.76 to 33.61kg/ha of NPK (Nitrogen, Phosphorus and Potassium) in different sacred forests.Conclusion Such nutrient release and dynamics in sacred forests, may contribute an effective nutrient flow to the topsoil as well as to the surrounding agricultural landscapes boosting agricultural productivity and sustainability. This signifies the role of sacred forests in rendering an important ecological service in terms of nutrient cycling.

Effects of dispersal on local population increase

2000 ◽  
Vol 3 (6) ◽  
pp. 479-482 ◽  
Author(s):  
J.M. Kean ◽  
N.D. Barlow
Keyword(s):  
Local Population ◽  
Population Increase

Seasonal Variation of Suicide in the City of São Paulo, Brazil, 1996–2010

Crisis ◽  
2014 ◽  
Vol 35 (1) ◽  
pp. 5-9 ◽  
Author(s):  
Daniel Hideki Bando ◽  
Fernando Madalena Volpe
Keyword(s):  
Seasonal Pattern ◽  
Total Sample ◽  
Sao Paulo ◽  
Seasonal Patterns ◽  
São Paulo ◽  
Health Statistics ◽  
Males And Females ◽  
June July ◽  
The City ◽  
Over Time

Background: In light of the few reports from intertropical latitudes and their conflicting results, we aimed to replicate and update the investigation of seasonal patterns of suicide occurrences in the city of São Paulo, Brazil. Methods: Data relating to male and female suicides were extracted from the Mortality Information Enhancement Program (PRO-AIM), the official health statistics of the municipality of São Paulo. Seasonality was assessed by studying distribution of suicides over time using cosinor analyses. Results: There were 6,916 registered suicides (76.7% men), with an average of 39.0 ± 7.0 observed suicides per month. For the total sample and for both sexes, cosinor analysis estimated a significant seasonal pattern. For the total sample and for males suicide peaked in November (late spring) with a trough in May–June (late autumn). For females, the estimated peak occurred in January, and the trough in June–July. Conclusions: A seasonal pattern of suicides was found for both males and females, peaking in spring/summer and dipping in fall/winter. The scarcity of reports from intertropical latitudes warrants promoting more studies in this area.

Three hundred years of House Sparrow (Passer domesticus) persecution in Germany

2007 ◽  
Vol 34 (2) ◽  
pp. 307-317 ◽  
Author(s):  
J. SEITZ
Keyword(s):  
Rural Areas ◽  
House Sparrow ◽  
Bird Species ◽  
Passer Domesticus ◽  
Second World War ◽  
Population Increase ◽  
World War ◽  
Large Numbers ◽  
Urban And Rural Areas ◽  
Second World

Modernization of agriculture, economic development and population increase after the end of the Thirty Years' War caused authorities in many parts of Germany to decree the eradication of so-called pest animals, including the House Sparrow. Farmers were given targets, and had to deliver the heads of sparrows in proportion to the size of their farms or pay fines. At the end of the eighteenth century German ornithologists argued against the eradication of the sparrows. During the mid-nineteenth century, C. L. Gloger, the pioneer of bird protection in Germany, emphasized the value of the House Sparrow in controlling insect plagues. Many decrees were abolished because either they had not been obeyed, or had resulted in people protecting sparrows so that they always had enough for their “deliveries”. Surprisingly, various ornithologists, including Ernst Hartert and the most famous German bird conservationist Freiherr Berlepsch, joined in the war against sparrows at the beginning of the twentieth century, because sparrows were regarded as competitors of more useful bird species. After the Second World War, sparrows were poisoned in large numbers. Persecution of sparrows ended in Germany in the 1970s. The long period of persecution had a significant but not long-lasting impact on House Sparrow populations, and therefore cannot be regarded as a factor in the recent decline of this species in urban and rural areas of western and central Europe.

Fecundity and Gonado-somatic Index of Trichiurus lepturus (Linnaeus, 1758) Along the Zamboanga del Norte Coast

2018 ◽  
Vol 6 (7) ◽  
pp. 120
Author(s):  
Ma. Dulce C. Guillena
Keyword(s):  
Sex Ratio ◽  
Stock Assessment ◽  
Chi Square ◽  
Moon Phases ◽  
Ovary Weight ◽  
Moment Coefficient ◽  
Trichiurus Lepturus ◽  
Significant Difference ◽  
The Relationship ◽  
Somatic Index

Gonado-somatic index and fecundity are tools for measuring the sexual maturity and ability of animals to reproduce.  This study investigates the reproduction of Trichiurus lepturus. Specifically, this aimed to determine the sex ratio, the GSI, the relationship between fecundity and total length, fecundity and total weight, fecundity and ovary weight. The Descriptive Method of research was used.  Percentage and chi-square was utilized in determining the percentage of occurrence and sex ratio respectively.   Pearson r Product Moment Coefficient of Correlation was used to determine the relationships of the parameters. The study revealed that females outnumbered males and the sex ratio for different month showed significant difference.  Spawning season was observed to occur in November and December as revealed in its GSI values and it synchronized with the full and new moon phases.  Fecundity is positively correlated with body weight, body size, and ovary weight where ovary weight is observed to be the best index for fecundity.  The results of this study could be used further for formal stock assessment of cutlassfish fishery.

Evaluation of Capacity of Salandi Reservoir Using Remote Sensing Data Along With Qgis Software

2018 ◽  
Vol 6 (8) ◽  
pp. 339
Author(s):  
Rupali Dhal ◽  
D. P. Satapathy
Keyword(s):  
Remote Sensing ◽  
Satellite Data ◽  
Remote Sensing Data ◽  
Project Work ◽  
Space Technology ◽  
Reservoir Water ◽  
Sediment Distribution ◽  
Sensing Data ◽  
Spread Area ◽  
Water Spread

The dynamic aspects of the reservoir which are water spread, suspended sediment distribution and concentration requires regular and periodical mapping and monitoring. Sedimentation in a reservoir affects the capacity of the reservoir by affecting both life and dead storages. The life of a reservoir depends on the rate of siltation. The various aspects and behavior of the reservoir sedimentation, like the process of sedimentation in the reservoir, sources of sediments, measures to check the sediment and limitations of space technology have been discussed in this report. Multi satellite remote sensing data provide information on elevation contours in the form of water spread area. Any reduction in reservoir water spread area at a specified elevation corresponding to the date of satellite data is an indication of sediment deposition. Thus the quality of sediment load that is settled down over a period of time can be determined by evaluating the change in the aerial spread of the reservoir at various elevations. Salandi reservoir project work was completed in 1982 and the same is taken as the year of first impounding. The original gross and live storages capacities were 565 MCM& 556.50 MCM respectively. In SRS CWC (2009), they found that live storage capacity of the Salandi reservoir is 518.61 MCM witnessing a loss of 37.89 MCM (i.e. 6.81%) in a period of 27 years.The data obtained through satellite enables us to study the aspects on various scales and at different stages. This report comprises of the use of satellite to obtain data for the years 2009-2013 through remote sensing in the sedimentation study of Salandi reservoir. After analysis of the satellite data in the present study(2017), it is found that live capacity of the reservoir of the Salandi reservoir in 2017 is 524.19MCM witnessing a loss of 32.31 MCM (i.e. 5.80%)in a period of 35 years. This accounts for live capacity loss of 0.16 % per annum since 1982. The trap efficiencies of this reservoir evaluated by using Brown’s, Brune’s and Gill’s methods are 94.03%, 98.01and 99.94% respectively. Thus, the average trap efficiency of the Salandi Reservoir is obtained as 97.32%.

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