Københavns Universitet
Uafhængig af ledelsen

PhD thesis defense

Xiaoxin Zhang defends her thesis at IGN, Geography section 2

PhD thesis defense — Xiaoxin Zhang defends her thesis: Unveiling China's Urbanization and Vegetation Restoration using Earth Observation


Date & Time:

Aud C, Department of Geosciences and Natural Resource Management, Øster Voldgade 10, 1350 Kbh K

Hosted by:
Geography section 2, Department of Geosciences and Natural Resource Management


Xiaoxin Zhang defends her thesis:

Unveiling China’s Urbanization and Vegetation Restoration using Earth Observation

Zoom link

Professor Rasmus Fensholt, IGN
Associate Professor Martin Brandt, IGN

Assessment committee:
Associate Professor Monika Kuffer, University of Twente, The Netherlands
Associate Professor Yuyu Zhou, Iowa State University, USA
Professor Hans Skov-Petersen (chair), IGN


While the negative and positive processes associated with urbanization and vegetation restoration are well understood, there is still a need to comprehensively analyze the trade-offs involved. Earth observation (EO) has been widely applied to study urbanization and vegetation dynamics. Advancements in computer science and high-resolution satellite technology have opened new opportunities for studying urban vegetation dynamics. Recent studies have reported successful application of cloud platforms and machine learning techniques in this field. Building upon this context, this thesis centers around the three questions: 1) To which extent and how is a large and transient carbon sink induced by urbanization and rural depopulation? 2) To what extent, in which locations, and how can vegetation browning from urban expansion can be balanced by urban greening in urban core areas based on segmentation methods using satellite time series? 3) What is the change in urban tree cover as a consequence of urbanization and urban tree planting in China? This thesis focuses on three interconnected questions that shed light on the relationship between urbanization, vegetation dynamics, and carbon neutrality.
In summary, this thesis utilizes advanced earth observation methods and analyzes the interplay between urbanization, vegetation recovery, along with the implementation of strategies for sustainable development. Specifically, it focuses on China’s efforts to balance urban expansion with vegetation restoration, emphasizing the significance of integrating green spaces and vegetation within urban landscapes. Three national-scale studies demonstrate the positive impacts of these initiatives on the society, economy and the environment, highlighting the potential for sustainable development in developing regions characterized by urbanization.