Quellpopulationen

Quellpopulationen, often translated as source populations or metapopulations, are a fundamental concept in ecology, particularly within metapopulation theory. A source population is defined as a group of individuals within a species that has a net positive reproductive rate, meaning it produces more offspring than are needed to replace the parents. These populations are characterized by high birth rates and/or low death rates, leading to a surplus of individuals.

This surplus of individuals from a source population can then disperse to other areas. These areas might be less productive habitats or areas where the population has gone locally extinct. The dispersing individuals can then establish new populations or reinforce existing ones. In the context of metapopulations, source populations are crucial for maintaining the overall persistence of a species across a fragmented landscape. They act as reservoirs of individuals that can recolonize patches that become vacant due to stochastic events or unfavorable conditions.

The concept of source populations is distinct from sink populations. Sink populations, in contrast, have a net negative reproductive rate, meaning they lose more individuals than they gain. These populations rely on immigration from source populations to persist. Without the continuous influx of individuals from source populations, sink populations would eventually disappear. Understanding the dynamics and distribution of source populations is therefore vital for conservation efforts, especially for species living in fragmented habitats.