Københavns Universitet
Uafhængig af ledelsen

PhD thesis defense

Nané Køllgaard Pedersen, IGN, defends her thesis at Landscape Architecture and Planning Section

PhD thesis defense — Nané Køllgaard Pedersen 4 March


Date & Time:

Aud A3-24.11, Department of Geosciences and Natural Resource Management, Rolighedsvej 23, 1958 Frederiksberg C

Hosted by:
Section of Landscape Architecture and Planning


PhD defence: Nané Køllgaard Pedersen

Afforestation by natural colonization – temporal changes, drivers and biodiversity in the initial three decades

Professor Inger Kappel Schmidt, IGN
Senior Consultant, PhD Anders Busse Nielsen, Naturstyrelsen Søhøjlandet

Assessment Committee:
Research Director Susanna Lehvävirta, University of Helsinki – Finland
Associate Professor Adam Felton, Swedish University of Agricultural Sciences, Alnarp – Sweden
Professor Lars Vesterdal (chair), IGN

The overall theme in this Ph.D. thesis is natural colonization as afforestation practice with focus on natural dynamics, drivers and biodiversity in the initial three decades and how simple management actions can facilitate the colonization. Forests play a significant role in mitigating the negative effects of climate change and the loss of biodiversity. The ability of forests to sequester and store carbon has led to ambitious goals of increasing the forest cover at national as well as international level. The new forests must however meet various other societal and economic needs and not least help in mitigating the loss of biodiversity. Natural colonization of previously cultivated fields is a relevant and inexpensive alternative to traditional afforestation, but has so far not been actively prioritized in afforestation in temperate climates on a larger scale. Unpredictability and a slow colonization are some of the reasons why the natural colonization has not been given higher priority in afforestation, where focus has been on meeting socio-economic values. However, the integration of natural colonization in afforestations can be a means of increasing biodiversity. This Ph.D. study aims to widen the understanding of the woody vegetation dynamics in the young phase of natural colonization. I investigated 33 areas laid out for natural colonization in Danish state forests from 1990-2018. I examined drivers and temporal dynamics over the three decades and compared biodiversity in natural colonization to plantations of same age. The results of the analyses can form the basis for planning afforestation with natural colonization as an integral part of the forest by utilizing the knowledge, that not only existing forest but also simultaneous afforestation, topography and soil type act as facilitators of colonization rate, species diversity and structural variation and thereby promote biodiversity in future forests.

A digital version of the PhD thesis can be obtained from the PhD secretary Anne Marie Faldt at anmf@ign.ku.dk