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.