Carbon cycle Nitrogen cycle 3 Climate change 2 Forest management 2 Forests 2 Forests and Forest Trees (Biology and Ecology) 2 Global warming 2 Nature conservation 2 Silviculture and Forest Management 2 Sustainability 2 Sustainable forestry 2 Acclimatization 1 Air pollution 1 Biodiversity 1 Biological Resources (General) 1 Biological Resources (Plant) 1 Carbon Dioxide 1 Carbon Inventory 1 Carbon Sequestration 1 Carbonfree Energies 1 Climate Change 1 Climatic change 1 Clouds 1 Conventional Energy 1 Decision making 1 EL Nino and NAO 1 Ecological disturbance 1 Ecological interrelationships 1 Energy transformations 1 Environmental Spectroscopy 1