Owing to its typical hydrographic and ecological conditions, the Baltic Sea is particularly 
sensitive to climate changes, pollution, and eutrophication as well as excessive exploitation of 
its resources. Below the permanent thermocline, there has been a marked reduction of species 
diversity and biomass affecting particularly flora and fauna living in or on the sea floor. 
Although deepwater conditions had briefly improved after the major inflow of highly saline 
water in 1993, the bottom zone of the Baltic has suffered substantially from continued oxygen 
deficiency and the temporary occurrence of hydrogen sulphide due to the prolonged 
stagnation period and continued high eutrophication level. Since the mid-80s, the decreasing 
salinity and oxygen deficiency in combination with overfishing have led, e.g. to a strong 
decline in cod stocks. 
Observation and investigation methods, analytical techniques 
The hydrographic, chemical, and biological conditions in the western Baltic and Baltic Proper 
are monitored by five yearly cruises. In addition, water exchanges between the North Sea and 
Baltic Sea are monitored by the MARNET station located on Darss Sill, which carries out 
permanent measurements, and hydrographic conditions in the Pomeranian Bight are monitored 
by the MARNET station ’’Oderbucht”. 
Monitoring is performed within the framework of the Federal and State Government 
Measuring Programme (BLMP) and the international commitments under the Helsinki 
Convention. The observation and investigation methods as well as the analytical techniques 
have been agreed internationally and are carried out in accordance with the Manual for the 
COMBINE programme of HELCOM. 
Products and services 
The scientific interpretation and evaluation of results is made in the form of yearly assessments 
of the hydrographic-chemical and marine biological conditions in the western Baltic and Baltic 
Proper as well as in special research reports. All measured data are archived at the German 
Oceanographic Data Centre (DOD). 
Contribution by the Landesamt für den Nationalpark Schleswig- 
Holsteinisches Wattenmeer, Tönning 
- Regional Office of the National Park Schleswig-Holstein Wadden Sea - 
TMAP - Trilateral Monitoring and Assessment Programme 
The concept of the Trilateral Monitoring and Assessment Programme (TMAP) is based to a 
large extent on the results of Germany’s ecosystem research in the Schleswig-Holstein 
Wadden Sea. 
Since January 1994, TMAP has been implemented jointly in Denmark, Germany, and The 
Netherlands as an operational Wadden Sea monitoring programme. Its approach is to address 
specific questions and to select the variables monitored with a view to high-priority problem 
fields taking into account interactions investigated within the framework of ecosystem 
research. The main phase of TMAP was adopted by the Trilateral Governmental Wadden Sea 
38