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New, easy to use, liquid nitrogen-cooled equipment is described for sampling the upper layer (80–160 mm) of water sediment and associated benthic organisms in streams and lakes up to 1.2 m deep. The sediment sample has an area of 0.0531 m2 and retains its natural composition and spatial structure. The two sampler components weigh 15 kg in total, which enables sampler use by hand, even in rural areas that are not readily accessible. A successful 2-year testing period in several first and second order streams demonstrated the suitability of the apparatus for sampling sediment textures ranging from fine clay to cobbles and current velocities up to 1 m s-1. [ABSTRACT FROM AUTHOR]

In the river Saale and in the terrestrial moss Mnium cuspidatum Leyss. in 1974/75 the annual production of Testacea and loricate ciliated protozoa were investigated. The production was estimated in the Saale-Aufwuchs on a β-meso ... oligosaprobic (Kaulsdorf, Thuringia, GDR) and on a α-mesosaprobic (Rothenstein, Thuringia, GDR) area of the river. The mosses were investigated in a forest near Jena. The production was estimated on slides and in special 'productionchambers'; the time of exposure was 2 weeks. Investigations concerned annual production of individuals and biomass, the ratio of annual production/standing crop ( P/B), numbers of generations per year ( G) and mortality ( M%/d). In the mosses, the rainfall modified the production and dislocation of the protozoa. The values for production are: Aufwuchs Saale (β-meso... oligosaprobic): 24·10 i/m· a (=1,0 g/m· a=79·10 i/m· d); P/B: 12.6. Aufwuchs Saale (α-mesosaprobic): 3.2·10 i/m· a (=0.35 g/m· a=81·10 i/m· d); P/B: 34.9; G: 22; M: 5%/ d. Moss: 145·10 i/m· a (=0.11 g/m· a=40.6·10 i/m· d); P/B: 8.1; G: 16.5; M: 3.0%/ d. [ABSTRACT FROM AUTHOR]