Aquatic bacterioplankton communities along salinity gradients: insights into composition community assembly and functional traits Mechanisms influencing community assembly and functional behavior of bacterial populations remain unclear particularly under shifting environmental conditions. Environmental filtering and competitive exclusion differently impacted the assembly of habitat specialists and generalists in response to salinity disturbances. Furthermore disturbance intensity can influence the extent of functional redundancy depending on community sensitivity. Overall this thesis demonstrates the feasibility of using novel experiments and integration of 16S rRNA and meta ‘omic’ data to address ecological aspects.<eng>