Szukana fraza: [Abstrakt = "The article conitains a discussion of literature dealing with the effect of temperature and concentration and kind of food, on seasonal and habitat variations \(both between habitats and within one habitat\) of zooplankton \(crustaceans and rotifers belonging to plankton filtrators and sedimentators\). Such variations relate both to the size and growth rate of individuals, and to length of development, length of life, reproduction rate and fertility. The results of a large number of field observations and laboratory experiments shows beyond doubt that there is a distinct correlation between variations in temperature and concentration and kind of food and differences, both seasonal parameters. Among the main factors determing variation in growth rate, reproduction, fertility and development of zooplankton, attention is drawn chiefly to the temperature factor, and less often to the food factor, a distinct tendency being observed here to carrying out experimental work in a laborartory at a constant temperature and referring the results obtained to natural conditions. As a result the effect exercised by the temperature gradient on development, growth and fertility of zooplankton is not taken into consideration."]