Relationship between the Processes of Production and Decomposition as the Index of the Succession State of Plankton Communities of the Ecosystem of the Regulated River (on the Example of the Teterev River)

Сalanoid copepods of the genus Pseudocalanus play an important role in the plankton communities of the Arctic and boreal seas, often dominating in numbers and constituting a significant proportion of the biomass of zooplankton. Despite their high presence and significance in the shelf plankton communities, species-specific studies of the biology of these are significantly hampered by extremely small morphological differences between them, especially at the juvenile stages, at which they are virtually indistinguishable. In this paper, we describe a new, routine and low-cost molecular method for identifying all Pseudocalanus species found in the Atlantic sector of the Arctic: the Arctic P. acuspes, P. minutus and the boreal P. moultoni and P. elongatus, and apply it to describe the relative distribution of these species in four locations of the Arctic and sub-Arctic. With this method, species-specific polymerase chain reaction (ssPCR), mass identification of individuals of any developmental stage, including nauplii, is possible. This method can serve as an excellent tool for studying the species-specific biology of this group, describing their life cycles, as well as monitoring changes in Arctic marine ecosystems under the influence of changing climate.

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Etude granulométrique de la charge de fond d'un canal de Miribel (Haut-Rhône) / Long profile and granulometric study of regulated river : The example of the Miribel Canal (Haut-Rhône)

Revue de géographie de Lyon ◽

10.3406/geoca.1989.5698 ◽

1989 ◽

Vol 64 (4) ◽

pp. 240-251 ◽

Cited By ~ 10

Author(s):

D. Poinsart ◽

Jean-Paul Bravard ◽

M. C. Caclin

Keyword(s):

Regulated River

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Impact of Feeding Activity of Silver Carp on Plankton Removal from a High-Rate Pond Effluent

Water Quality Research Journal ◽

10.2166/wqrj.2005.022 ◽

2005 ◽

Vol 40 (2) ◽

pp. 191-201 ◽

Cited By ~ 2

Author(s):

Nadia Berday ◽

Driss Zaoui ◽

Abdeljaouad Lamrini ◽

Mustapha Abi

Keyword(s):

Feeding Activity ◽

Silver Carp ◽

Treatment Plant ◽

High Rate ◽

Fish Pond ◽

Gut Contents ◽

Hypophthalmichthys Molitrix ◽

Technology System ◽

Solids Concentration ◽

Plankton Communities

Abstract The effect of silver carp (Hypophthalmichthys molitrix Val.) feeding activity on the plankton communities in a high-rate pond technology system (HRPTS) effluent was investigated over a period of 100 days. The experiment was conducted at the experimental wastewater treatment plant of the Agronomic and Veterinary Medicine Institute (AVI) of Rabat, Morocco, using a HRPTS in a fish pond receiving the plant effluent. The effluent was highly dominated by phytoplankton (99.95%). Silver carp could survive and grow in the fish pond. Production was 37 kg with a very low mortality rate (12%). The high specific intestine weight (7%) and intake rates of biomass and phytoplankton by silver carp (616 g kg-1 of fish day-1 and 1.6 x 1011 cell kg-1 of fish day-1, respectively) demonstrated the importance of the feeding activity of the fish. Zooplankton intake rates were lower (2 x 107 bodies kg-1 of fish day-1). The high intestine index (3 to 4.3 for fish sizes of 14 to 22 cm) and the dominance of phytoplankton in the gut contents (99.95%) confirmed an omnivorous/ phytoplanctivorous diet. Silver carp were efficient in removing plankton from the HRPTS effluent. The net removal yields of biomass were 285 g m-3 day-1 and 322 g kg-1 of fish day-1, 7 x 1010 algal cells kg-1 of fish day-1 and 8.7 x 107 zooplankton bodies kg-1 of fish day-1, with net removal rates of 47, 64 and 62%, respectively. The total suspended solids concentration decreased from 211 in the inflow to 112 mg L-1 in the fish pond.

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A New Life for the St. Croix River

Water Quality Research Journal ◽

10.2166/wqrj.1988.044 ◽

1988 ◽

Vol 23 (4) ◽

pp. 568-577

Author(s):

Harold S. Bailey

Keyword(s):

Water Quality ◽

Dissolved Oxygen ◽

Discharge Rate ◽

Paper Mill ◽

Regulated River ◽

Secondary Treatment ◽

Pulp And Paper Mill ◽

Oxygen Regime ◽

Oxygen Concentrations

Abstract The water quality of the upper 110 kilometres of the St. Croix River is considered to be pristine. A major industrial discharge renders the lower 14 kilometres of the river a water quality limited segment. Prior to 1970 the Georgia-Pacific Pulp and Paper Mill at Woodland, Maine, discharged untreated effluent directly into the river causing dissolved oxygen concentrations to drop well below 5 mg/L, the objective chosen in the interest of restoring endemic fish populations. Since 1972, the Mill has installed primary and secondary treatment, regulated river discharge rate and effluent composition which has greatly improved the summer dissolved oxygen regime. By 1980, dissolved oxygen concentrations were generally above 5.0 mg/L and restocking the river with Atlantic Salmon (Salmo salar) was initiated.

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