Transcript Slide 1
Monitoring macroinvertebrater in Norwegian rivers? Torleif Bækken , NIVA Data in database (NIVA base) relative to ASPT 9.00 8.00 7.00 ASPT 6.00 5.00 Potential ref. sites, but where and type? 4.00 3.00 2.00 1.00 0.00 prøvenummer 1-680 Data in database (NIVA base) relative to EPT species EPT NordNorge EPT SørVest EPT ØST-Tr 32 32 32 28 28 28 24 24 24 20 20 20 16 16 16 12 12 12 8 8 8 4 4 4 0 0 0 20 30 25 50 75 10 Count Axis Count Axis 5 10 15 20 Count Axis The initial intercalibration selection on river types Eutrophicated rivers H/G G/M 14 12 10 8 6 4 2 0 RN1 RN2 RN3 RN4 RN5 RN6 RN7 RN8* Reference intercalibration data? Norway with sufficient data on two types: R-N1 and R-N4 R-N1 and R-N4 (lowland types) 52 sites inkluding 9 reference sites Ongoing monitoring of rivers Monitoring Norwegian reference rivers: Atna (mountainboreal), Vikedalselva (acidification, montain-boreallowland). Monitoring liming/acidification: several rivers at the south and west of Norway. Some few in the north and east. Oslo rivers pollution monitoring (very 2-5 years), some ”references”? Almost all other Norwegian invertebrate data is from short time point source monitoring. Lack of additional data to define reference conditions Methods Sampling: mostly 3x1 min kick, some 5x1 min, 1x1 min, some with no time frame. Sorting: no systematic common approach (NIVA: subsampling, counting all in 1. subsample, then the less common (< 20) in next samples, all subsamples to look for species in few numbers.) Taxa level: All to main groups, EPT to species, elmiidae to species and few other groups. Sampling frequency: 1-2 times/year (prefer autumn) Classification No national system (or under development?) Raddum (national monitoring acidification/liming), NIVA (regional east) ASPT (depending on institution/person) EPT (depending on institution/person) Trent modified (Oslo rivers) Supporting information Acidification: pH, alk, and most anions and cations Other monitored variables depend on the purpose Problem: when chemical variables and macroinvertebrates have been monitored in the same program (acidification/liming), there have often been lack og coordination in time and site.