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In this opinion paper we investigate the effects of forest management on animal and plant biodiversity
by comparing protected areas with intensively and extensively managed forests in Germany and in
Romania. We want to know the extent to which differences in diversity of Romanian compared to German
forests are based on management.
The number of tree species was not different in protected and managed forests ranging between 1.8 and
2.6 species per plot in Germany and 1.3 and 4.0 in Romania. Also herbaceous species were independent of
management, ranging between 13 species per plot in protected forests of Romania and 38 species per plot in
German coniferous forest. Coarse woody debris was generally low, also in protected forests (14 to 39m3 ha−1).
The main difference between Romania and Germany was the volume of standing dead trees (9 to 28m3 ha−1
for Romania), which resulted in larger numbers of forest relict saproxylic beetles independent of management.
Large predators (wolves, bears and lynxes) are only found in regions with low human intervention. Thus, we
identified a “cut and leave” type of management in Romania, in which clear-felling of forest are followed by
long periods of no human intervention. Forests managed in the “cut and leave” mode contained the highest
diversity, due to a natural succession of plant species and due to habitat continuity for animals. In Germany
intensive management eliminates poorly formed tree individual and species of low market value during stand
development. Forest protection does not ensure the maintenance of more light demanding key species of earlier
stages of succession unless competition by shade-tolerant competitors is reduced through disturbances.
We compare the economics of intensive and extensive management. The “cut and leave” mode delivers less
wood to the wood market, but saves expenses of tending, thinning and administration. Thus the net income
could be quite similar to intensive management at a higher level of biodiversity.
Our analysis suggests that forest protection per se does not yet ensure the maintenance of species. Clearfelling
followed by natural succession may even be superior to the protection
