Some studies on the ecology of limnetic crustacean zooplankton in Lake Begnas and Rupa, Pokhara Valley, Nepal

Introduction: Conjunctivitis is a common health problem in Nepal. It is inflammation of conjunctiva presenting as red eye. It is a communicable eye disease. Health education to the students and proper management can help spread of the disease. Knowledge of conjunctivitis among school students will help in prevention of the disease. So the study was carried out to assess the knowledge of conjunctivitis among high school students in Pokhara valley of Western Nepal. Materials/ Methods: A school based cross sectional study was performed among six government schools in western Nepal from May 2019 to June 2019. Students from grade eight, nine and ten were included in the study. Data was collected using structured questionnaire including demographic data, knowledge regarding sign symptoms of conjunctivitis, treatment, prevention, complication of conjunctivitis. Data was analysed using SPSS version 11.6. Result: A total of 523 students were included in the study. The mean age of the students was 14.7 ± 1.2 years with majority of females (53%). Nearly 2/3rd of the students (61.6%) had heard of conjunctivitis. Majority of the students (87.4%) of the students mentioned that it is communicable while 80.3% of the students correctly mentioned its etiology. Majority of the students (97.9%) mentioned that it is curable with treatment as first option (97.5%). Majority of the students (98.3%) correctly responded to the preventive measures but majority of the students (83.2%) wrongly mentioned mode of transmission. Conclusion: Secondary school students in Western Nepal have poor knowledge of conjunctivitis. Appropriate eye health education should be given to school students to prevent rapid spread of infective conjunctivitis.

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Changes in the crustacean communities of Lakes Michigan, Huron, and Erie following the invasion of the predatory cladoceran Bythotrephes longimanus

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f04-149 ◽

2004 ◽

Vol 61 (11) ◽

pp. 2111-2125 ◽

Cited By ~ 105

Author(s):

Richard P Barbiero ◽

Marc L Tuchman

Keyword(s):

Zooplankton Community ◽

Crustacean Zooplankton ◽

Bythotrephes Longimanus ◽

Zooplankton Community Structure ◽

Cladoceran Species ◽

Invertebrate Predators ◽

Predatory Cladoceran ◽

Leptodora Kindti ◽

Escape Responses ◽

Zooplankton Communities

The crustacean zooplankton communities in Lakes Michigan and Huron and the central and eastern basins of Lake Erie have shown substantial, persistent changes since the invasion of the predatory cladoceran Bythotrephes in the mid-1980s. A number of cladoceran species have declined dramatically since the invasion, including Eubosmina coregoni, Holopedium gibberum, Daphnia retrocurva, Daphnia pulicaria, and Leptodora kindti, and overall species richness has decreased as a result. Copepods have been relatively unaffected, with the notable exception of Meso cyclops edax, which has virtually disappeared from the lakes. These species shifts have for the most part been consistent and equally pronounced across all three lakes. Responses of crustacean species to the Bythotrephes invasion do not appear to be solely a consequence of size, and it is likely that other factors, e.g., morphology, vertical distribution, or escape responses, are important determinants of vulnerability to predation. Our results indicate that invertebrate predators in general, and invasive ones in particular, can have pronounced, lasting effects on zooplankton community structure.

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Cadmium concentrations of crustacean zooplankton of acidified and nonacidified Canadian Shield lakes

Environmental Science & Technology ◽

10.1021/es00079a010 ◽

1990 ◽

Vol 24 (9) ◽

pp. 1367-1372 ◽

Cited By ~ 16

Author(s):

Norman D. Yan ◽

Gerald L. Mackie ◽

Peter J. Dillon

Keyword(s):

Canadian Shield ◽

Crustacean Zooplankton ◽

Shield Lakes

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A biophysical model of the interaction between vertical migration of crustacean zooplankton and circulation in the Lower St. Lawrence Estuary

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-095 ◽

1999 ◽

Vol 56 (12) ◽

pp. 2420-2432 ◽

Cited By ~ 15

Author(s):

Bruno A Zakardjian ◽

Jeffrey A Runge ◽

Stephane Plourde ◽

Yves Gratton

Keyword(s):

Population Dynamics ◽

Vertical Migration ◽

Horizontal Distribution ◽

Calanus Finmarchicus ◽

Biophysical Model ◽

Crustacean Zooplankton ◽

Simple Formulation ◽

Lawrence Estuary ◽

Circulation Patterns ◽

St Lawrence Estuary

As an essential step in modeling the influence of circulation on the population dynamics of marine planktonic copepods, we define a simple formulation of swimming behavior that can be used in both Eulerian and Lagrangian models. This formulation forces aggregation of the population toward a preferential depth and can be stage specific and time varying, thus allowing description of either diurnal or seasonal vertical migration. We use the formulation to examine the interaction between the circulation and vertical distribution in controlling horizontal distribution of the common planktonic copepod Calanus finmarchicus in the Lower St. Lawrence Estuary, Canada. We first introduce diel migration into a simple one-dimensional model and then into a model of residual two-dimensional circulation patterns representative of conditions encountered in the Lower St. Lawrence Estuary. Results from the latter indicate that interactions between circulation and stage-specific swimming behaviors are the main mechanisms for aggregation of planktonic crustaceans at the head of the Laurentian Channel and highlight the implications of flushing of the surface-dwelling young stages for the population dynamics of C. finmarchicus in the Lower St. Lawrence Estuary.

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