There are also some special post codes: the airport has its own post code (1300), the UN (1400) and some big companies also have their own post code, for example the ORF, the Austrian National Broadcasting Service (1136).
Two different types of succession, primary and secondary, have been distinguished. Primary succession occurs in essentially lifeless areasâregions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. Secondary succession occurs in areas where a community that previously existed has...
Ecologists (scientists who study the relationships of organisms with their living and nonliving environment) generally recognize two kinds of succession, primary succession and secondary succession. Primary succession takes place on an area that is originally completely empty of life. As an example, an area that has been covered by a flow of lava has, for a time, no life at all on it. Over a period of time, however, various kinds of organisms begin to grow in the area.