International Cooperative Programme on Assessment
and Monitoring of Acidification of Rivers and Lakes
Ms. B. Kvaeven
Head of Programme
Centre: Ms. M. Johannessen Ulstein
Acidification of freshwater systems
provided some of the earliest evidence of the damage
caused by sulphur emissions. The sensitivity of
these systems suggested that they were ideal for
studying the effects of, and response to changes
in, pollution deposition.
The objectives for ICP Waters are
to assess, on a regional basis, the degree and geographical
extent of acidification of surface waters. The data
collected should provide information on dose/response
relationships under different conditions and correlate
changes in acidic deposition with the physical,
chemical and biological status of lakes and streams.
The Programme is planned and coordinated
by a Task Force under the leadership of Norway.
Chemical and site data from more than 200 catchments
in 24 countries in Europe and North America are available
in the database of the Programme Centre at the Norwegian
Institute for Water Research (NIVA), Oslo.
Monitoring of river and lake sites
includes both chemistry and biology. All major chemical
constituents are included in the analytical programme
and are used for long-term trend analyses of water
quality. For about half of the sites both chemical
and biological data have been reported and these
sites are used for dose/response evaluations.
Invertebrates, small animals living
in or on the bottom of lakes and streams or in open
water, often occur in large numbers in freshwaters.
Different species have specific tolerance limits
related to water chemistry, physical conditions,
etc. For this reason, sampling invertebrate communities
is a useful tool in environmental studies such as
acidification. Similarly, diatoms, microscopic algae
that are abundant in a wide range of freshwaters,
also indicate water quality. However, these have
the additional advantage that their remains are
found in sediments, providing a historic record
of the water quality.
The monitoring of fish populations
became part of the ICP Waters programme in 1992.
While fish species may live for many years, they
often have life stages with differing sensitivities
to acidification. Since changes to these stages
are not necessarily detected in the same year, the
fish monitoring programme employs methods to detect
changes in the different life stages of the population
Quality control is an important
part of the programme. Annual laboratory intercalibration
exercises were established in 1987, involving, in
1998, 43 laboratories in 20 countries. Database
checks ensure the quality of the data which are
being collected and used. Biological quality control
started in 1992.
Further information is available
from the Programme