Published in Encyclopedia of Inland Waters
The Megalopterans represent an old insect group and one not extremely speciose, having approximately 275 described species. Neotropical and Indomalayan biogeographic areas probably hold the most species, whereas Nearctic and Australian species are the most well studied. The aquatic larvae are medium-to-large predaceous insects found in a wide varie...
Published in Encyclopedia of Inland Waters
The mechanics of recruitment to species-specific populations of phytoplankton are reviewed. Importance is attached to distinguishing among physiological analogs of growth, increase in biomass, cell replication rate and net population changes, and to the correct separation of the expression of rate- and yield-limiting factors. Phytoplankton growth a...
Published in Encyclopedia of Inland Waters
Allelochemical reactions are chemically mediated interactions between organisms that affect individuals and populations and might influence trophic interactions. Many inter- and intraspecific interactions are, at least in part, regulated by allelochemicals. Predator–prey interactions are influenced by either kairomones allowing prey to chemically d...
Published in Encyclopedia of Inland Waters
Dynamic performances of phytoplankton weaker in natural environments than those in culture are attributable to the greater variabilites in temperature, photoperiod and incident light intensity obtaining. Commonly, a critical shortage of supply of an essential resource depresses the attainable rate of cell replication. In nature, phytoplankton popul...
Published in Encyclopedia of Inland Waters
In most textbooks, algae, in general, appear as cosmopolitan species that occur anywhere at any time, therefore are, in addition, ubiquitous. In this article we demonstrate that algal species can be quite restricted in their geographical distribution exhibiting similar patterns as higher plants. Mechanisms of dispersal, dispersal agents, and surviv...
Published in Encyclopedia of Inland Waters
There is growing evidence that free-living freshwater nematodes, previously largely neglected, play important roles in ecosystem function. In freshwater sediments, nematodes are usually the most abundant organismal group of metazoans, and they are found from the polar regions to the tropics. In lakes and rivers, nematodes dominate the meiobenthos, ...
Published in Encyclopedia of Inland Waters
Freshwater mollusks are a large, diverse group, which includes snails (class Gastropoda) and clams and mussels (class Bivalvia). Mollusks have a body plan that includes a calcium carbonate shell, mantle tissue, and a muscular foot. Gastropods have a well-developed head with tentacles, a foot modified for creeping, and a univalve shell that is usual...
Published in Encyclopedia of Inland Waters
This article represents a relatively brief review of some of the unusual physical properties of water, and gives examples of how those properties may influence the world of inland waters. Subtopics include discussions on (1) density, including the nonlinear changes of density with changes in water temperature, and how that interesting property may ...
Published in Encyclopedia of Inland Waters
Freshwater bodies dominated by dissolved humic substances (HSs) seem to be the major type of inland waters. HSs are natural environmental chemicals and directly interact with organisms. HSs adversely interfere with photosynthesis and suppress cyanobacteria more than eukaryotic algae. Quinones in the HSs appear to be the effective structure. HSs exe...
Published in Encyclopedia of Inland Waters
Phytoplankton are, by definition, photosynthetic, and include cyanobacteria as well as algae. Most of the phytoplankton in inland waters obtain all of their energy from light and their chemical requirements from dissolved inorganic solutes, i.e., they are photolithotrophs. Growth rate limitation by resource supply in photolithotrophic phytoplankton...
