Sustainability is a very important issue in forestry. The monito-
ring and evaluation of sustainability in our forest is still a
methodological problem because the selection of indicatorsfor
evaluating the impact of human land use is arbitrary and not
supported by a strong ecological framework. According to new
ecosystem theories based on thermodynamics, ecosystems and radia-
tion blanace is thus a potential indicator for the complexity/
integrity of ecosystems. A monitoring protocol will be elabora-
ted. Also a new indicator for forest structure will be developed
since the diversity of structure is a major factor for creating
habitat and species diversity. Several new sensors and technolo-
gies will make it possible to measure the structure in a stan-
dardised way. The new developed indicators will be tested in
forest reserves and managed forests.