without disturbance benefited the vegetation development.
Within an alley cropping system the diversity of the vegetation
communities was seen to increase with the longer rotation
periods. In contrast to this, the diversity of vegetation
decreased in older stands, again this is due to the shadow
influences under the closed canopy of the larger trees.
Comparable results were found for carabids (Fig. 4). A
generalisation of these findings would be rather questionable
at the current stage, therefore further research is necessary. In
contrast to the vegetation or the carabid diversity, the
abundance of enchytraeidae was seen to reach the highest
amount within the crop field and not within the tree rows.
Biodiversity is a main topic of the national sustainability
strategy in Germany (Doyle et al., 2005). The goal of this
strategy is the reduction in the rate of Biodiversity loss till
2010. Based on the current developments, it will not be
possible to fulfil the goal, as also stated in the Millennium
Ecosystem Assessment (MA, 2005). Under nature conservational
aspects a maximisation of structural diversity is an
essential fundament to come close to the concepts outlined in
the national sustainability strategy. Such structural diversity
is provided by agroforestry systems such as alley cropping,
where different structures alternate at the small scale. Such
systems have been rated strictly higher than short rotation
coppices. From the nature conservational point of view
structural diversity in landscapes is an important goal and
principally therefore alley cropping systems have to be
preferred. Beneath the structure, such land use systems have
many additional beneficial effects to the neighbouring landscape.
They represent an extensive production with perennial
durations free of disturbance. Additionally, the organic topsoil
develops differentiated horizons which act as different
habitats for specialised organisms. The importance of such
tree rows for animal’s results from the different functions of