The Dynamics of Aquatic Systems: A Comparative Study of the Structure of Four Zooplankton Communities

Abstract

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A partial analysis of ecological segregation in the chironomid community of a bog lake

“…58, 2, pag . 129-135, 1978 munities is to study the degree of ecological overlap of the community members at progressively more refined levels in an attempt to reveal the mechanisms of segregation (Heip, 1973 ;Lanciani, 1970 ;Lane, 1975 ;Paine, 1963 ;Zaret & Rand, 1971) .…”

Zooplankton Niches and the Community Structure Controversy

“…First, it is crucial in delineating community structure to select an appropriate spatial-temporal framework for the orga- (5,7). Diaptomus and Cyclops species can seize the same prey species (7,8).…”

“…Pelagic filter feeders are an example. I have used Levins's (11) equations to evaluate zooplankton community structure (5) and to find consistent indices. This analysis centers on several niche measures that are calculated from density values and distribution patterns for a set of coexisting species.…”

“…Second, Lane misinterprets (1) the implication of the individualistic concept for community structure. The principle of species individuality (6) may be stated as follows: "Each species is distributed in its own way, according to its own genetic, physiological, and life-cycle characteristics and its way of relating to both physical environments and interactions with other species; hence, no two species are alike in distribution" (5). The existence of structure or species interactions in a community does not invalidate the principle of species individuality.…”

Some observations on the diet and food selection ofDaphnia hyalina (Cladocera) in an eutrophic lake

“…E is the electivity index according to Ivlev, r i the relative algal density in the gut and Pi the relative algal density in the lake (Eqn,1). carried out by TAPPA (1965), LANE (1975, NADIN-HURLEY and DUNCAN (1976), LEI andARMITAGE (1980) andHULSMANN (1983 (GELLER, 1975;LAMPERT, 1977LAMPERT, , 1981LAMPERT, , 1982. The blue-greens can be very variable in respect to toxicity (HENNI NG and KOH L, 1981).…”