This research was focused on the relationship between river discharge and organism drift. It was carried out for three years in a small heavily modified river in Saxony (Germany). The amount and species composition of drifting invertebrates were observed, depending on discharge and flow velocity. A station was installed where the flow velocity was continually measured and drifting organisms were caught with nets. An inventory of the aquatic community (benthic invertebrates) was taken to determine the species living in the river at the research station. The highest drift density measured was 578 organisms per m3 at a flow velocity of 0.90 m s-1 , the mainly drifting organisms were Chironomidae. Different organisms groups started drifting at different flow velocities. Heavy impacts, such as dredging the river and flood waves, affected the aquatic ecosystems and severely changed the aquatic community regarding the number and the diversity. Some of the aquatic invertebrates such as the Anthothecata completely disappeared after dredging. It was found that many different terrestrial organisms were part of the drift. The typical family of soil biota Collembola represented the largest share.
e analyzed the song pattern of the black redstart (Phoenicurus ochruros) from the Haibei area and compared it to three other recording sites on the Tibet Plateau using the Avisoft-SAS Lab program. Five extracted functions identified individuals from the Haibei population. By comparing populations from the Tibet Plateau (China), Slovakia (Central Europe), Germany and other sites in Europe, we established that the maximum song frequency was lowest in the Haibei population of the Tibet Plateau. On a large geographic scale, song differences increased with geographic distance. Black redstarts sing lengthy songs composed of two parts in both the Tibet Plateau and in Europe. However, while these two sections were totally or partly identical within the Tibet Plateau population, they were totally different in European populations. Redstart songs in the Tibet Plateau share a syllable of scrunching sound, while European individuals have a homologous section composed of repeat elements.