Semiconservative replication was not the only model of DNA replication proposed during the mid-1950s, however. In fact, two other prominent hypotheses were put also forth: conservative replication and dispersive replication.
Main idea. Aquatic ecosystems are grouped based on abiotic factors such as water flow, depth,distance from shore, salinity, and latitude. Freshwater ecosystems. The major freshwater ecosystems include ponds, lakes, streams,rivers, and wetlands.
Biotic factors, as well as abiotic factors, have more to do with how those parts of an ecosystem affect one another than the specific living or non-living thing itself. Biotic factors in an ecosystem are the living things that affect other living things in that ecosystem. Competition, consumption, predation, parasitism, disease, even symbiosis are all ways a biotic factor could have an effect on the other creatures they encounter.