RD&D-Programme 2004 - SKB

certain substances, such as uranium, which means that they do not accompany the water stream
but are accumulated outside the root.
In parallel with the work with the CoupModel, a compilation has been made of existing
radioecological models for forest. It will result in a forest model that uses existing methodology
with uptake factors to calculate doses in forest ecosystems.
A field study of how different substances are accumulated in fungal mycelia has been initiated
by SLU in the Forsmark area. Together with element analyses of soil profile type and vegetation
from the site investigations, this study will provide a valuable quantification of root uptake
factors for different substances.
An important source of greater understanding of terrestrial ecosystems is the site investigations,
and the unique studies that have produced e.g. vegetation maps /20-47, 20-53, 20-54/ and the
soil map /20-55/ are a good starting point. The work which SKB’s analysis group will do to
describe the site /20-2/ is essential to both describe the dominant processes and obtain data for
the models. A further development of the satellite image interpretation of the vegetation has
been used to compile and test different indices for determining the vegetation’s production
/20-56/.
There has been a regular exchange of information on forest ecosystems with Posiva via meetings
and workshops. Posiva has an extensive research programme regarding certain processes in
the forest /20-57/.
The ontogeny (succession) of a marine area to a lake and then a mire was described in connection
with the Safe project /20-45, 20-58 to 20-60/. This was followed up by subsequent studies
where lake infilling is simulated /20-43/ and lake ontogeny is described /20-44/.
An extensive literature review has been performed where the occurrence, ecology, hydrology
and transport properties of wetlands are compiled /20-61/. It is the basis for a process description
for wetlands.
Additional information is now being compiled for the more than 400 boreholes in northern
Uppland. The compilation is being done by the limnology departments at Uppsala and Umeå
universities. Wetlands have been mapped in the Quaternary geology investigations on the sites,
and wetlands without groundwater connection have been discovered. Furthermore, the vegetation
map /20-47/ provides valuable information.
A review of the consequences of crop irrigation has been done and dose models using irrigation
have been updated /20-62/.
Programme
The work of defining and describing the dominant processes in terrestrial ecosystems will
continue. The CoupModel will continue to be evaluated and a coherent transport model for
terrestrial ecosystems will be developed. The succession and dynamics in the terrestrial systems
– for example grazing, harvesting and decomposition – will also be modelled during the period.
The site investigations will be an important source of understanding of the processes in the
ecosystem, in addition to providing important data for the models. It is above all the quantification
of different processes that will provide important information and support for models and
assumptions. The results of the hydrological measurements and the chemical measurements of
soil and biota composition will be important.
The following activities have been commenced or are planned during the upcoming period:
• Studies of distribution of biomass, primary production and the carbon cycle in different
forest types, including swamp forests.
• Studies of historical and potential exploitation of different types of land on the sites in
question.
282 RD&D-Programme 2004