Seasonal abundance of limnetic crustacean zooplankton in Lake Phewa, Pokhara Valley, Nepal

The lakewide horizontal distribution and seasonal abundance of the cyclopoids, cladocerans, and calanoids in Lake Erie from April to December 1970, are presented.Over much of the year cyclopoids dominated by Diacyclops bicuspidatus thomasi were most numerous with offshore centers of abundance. Several species of cladocerans, often with short peaks of occurrence, were most abundant during summer in the Western basin and associated with south shore population centers in the Central basin. Calanoids were frequently much less abundant than either of the two groups but present in the same areas as the cladocerans.Most species present were short-lived with a high reproductive potential. Environmental clues are postulated to control specific abundance making group numbers more constant. Several life-cycle patterns were evident including species with spring–fall maxima and those with a single peak.Timing of peak abundance of certain species and groups varies from west to east in the same fashion as temperature differences giving rise to east–west gradients of abundance which change with season. Cladoceran and calanoid groups show similarities in distribution pattern with estimates of particulate organic material rather than with algal abundance resulting in north–south gradients of abundance.

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

Hydrobiologia ◽

10.1007/bf00016765 ◽

1980 ◽

Vol 70 (3) ◽

pp. 235-245 ◽

Cited By ~ 11

Author(s):

D. B. Swar ◽

C. H. Fernando

Keyword(s):

Crustacean Zooplankton ◽

Pokhara Valley

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Seasonal Variations of Zooplankton, Chlorophyll-A and Nutrients in Phewa Lake, Pokhara Valley, Nepal

Ecoprint An International Journal of Ecology ◽

10.3126/eco.v16i0.3473 ◽

1970 ◽

Vol 16 ◽

pp. 51-57

Author(s):

Md. Akbal Husen ◽

Ram Prasad Dhakal

Keyword(s):

Chlorophyll A ◽

Phytoplankton Biomass ◽

Dominant Species ◽

Trophic Status ◽

Seasonal Pattern ◽

Zooplankton Species ◽

Total Phosphorous ◽

Different Seasons ◽

Pokhara Valley ◽

Lake Phewa

In order to understand trophic status of lake Phewa, largest lake (535 ha) in Pokhara valley, seasonal pattern of zooplanktons, chlorophyll a and nutrients level in water column was examined from January to December 2005. Total zooplanktons density was highest in January and November, showed bimodal pattern in Lake Phewa. The sequence of dominant species of zooplankton was Nauplius > Kerratella > Cyclops > Daphnia > Eodiaptomus in this lake. Correlation between zooplankton species and nutrients level was established. The Chlorophyll- a as an indicator of phytoplankton biomass peaks in November and chlorophyll-a concentration was found lower in winter months. The NH4-N ranged between zero to 0.021 mg/l with mean of 0.003 mg/l. The annual concentration of nitrate+nitrite (NO3+NO2) was found upto 0.148 mg/l (mean= 0.013 mg/l), soluble reactive phosphate (PO4-P) ranged from zero to 0.003 mg/l (mean= 0.001 mg/l), and total phosphorous ranged upto 0.052 mg/l (mean= 0.009 mg/l) in lake Phewa in 2005. Based on nutrients and chlorophyll-a dynamics, the lake varied from mesotrophic to eutrophic in different seasons. The Phewa Lake fluctuated from oligo-mesotrophic in monsoon seasons to meso-eutrophic in dry periods. Key words: Zooplanktons, nutrients, chlorophyll. DOI: 10.3126/eco.v16i0.3473ECOPRINT 16: 51-57, 2009

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Seasonal Abundance of Crustacean Zooplankton and Net Plankton Biomass of Lakes Huron, Erie, and Ontario

Journal of the Fisheries Research Board of Canada ◽

10.1139/f74-050 ◽

1974 ◽

Vol 31 (3) ◽

pp. 309-317 ◽

Cited By ~ 57

Author(s):

N. H. F. Watson ◽

G. F. Carpenter

Keyword(s):

Lake Erie ◽

Dry Weight ◽

Lake Huron ◽

Seasonal Abundance ◽

Crustacean Zooplankton ◽

Average Weight ◽

Calanoid Copepods ◽

Western Basin ◽

Saginaw Bay ◽

Western Lake

Crustacean zooplankton concentrations (numbers per m3) in the upper 50 m found in lakewide cruises during all or most of the seasons on lakes Ontario and Erie in 1970 and on Lake Huron in 1971 showed that the species of zooplankton crustaceans present in the three lakes were generally identical, although the times of maxima and relative species compositions differed. Calanoid copepods were most abundant and diverse in Lake Huron and western Lake Erie. Cyclopoids and cladocerans were most abundant in lakes Erie and Ontario and in the Saginaw Bay region of Lake Huron. The most abundant cyclopoid throughout the year in all three lakes was Diacyclops bicuspidatus thomasi; Tropocyclops prasinus and Acanthocyclops vernalis were abundant especially in lakes Ontario and Erie, respectively. Cladocerans were most numerous in lakes Erie and Ontario. Numbers of individuals fluctuated markedly through the season with maxima in the spring or summer months in all three lakes.Biomass values (ash-free dry weight) were highest in Lake Erie, especially the Western Basin, and in Saginaw Bay of Lake Huron. Although numbers of crustaceans/m3 were much lower in Lake Huron than in Lake Ontario, net biomass values were similar. This was due to the greater size and average weight of crustaceans in Lake Huron samples. Inshore waters of lakes Ontario and Huron and all three basins of Lake Erie were subject to greater fluctuations in concentrations of crustacean zooplankton and net biomass values than in the pelagic waters of lakes Ontario and Huron.

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STUDY ON DIVERSITY AND DISTRIBUTION OF ANTS (HYMENOPTERA: FORMICIDAE) IN URBAN AND PERIURBAN AREAS OF AURANGABAD CITY, MAHARASHTRA, INDIA

FLORA AND FAUNA ◽

10.33451/florafauna.v23i2pp404-410 ◽

2017 ◽

Vol 23 (2) ◽

Author(s):

S. D. CHATE ◽

R. J. CHAVAN

Keyword(s):

Rainy Season ◽

Winter Season ◽

Seasonal Abundance ◽

Urban Region ◽

Ant Community ◽

Community Variation

The present study deals with the ant community variation in and around Aurangabad city. During the study total 16 species of ants belonging to twelve genera and four subfamilies were reported in eight habitat from urban and periurban regions. Abundance of ants was more in peri-urban region as compared to urban region. Subfamily myrmicinae was more dominant as compared to other subfamilies. Seasonal abundance of ants was seen to be more in winter season and less in rainy season.

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