Kalle's main research areas were labor market economics, natural resource economics (mainly forest economics) and environmental economics. In the field of labor market economics, he studied, among other things, wage formation and labor market policy. Kalle's most important contribution in the field of natural resource economics was to integrate natural resources and, above all, forestry into modern microeconomic theory. Some examples are modeling of forest owners' decision problems and optimal choices, goal conflicts in connection with forestry, and how the timber markets work. In the field of environmental economics, he worked primarily with theory formation on green national accounts and their connection to measures of economic welfare and sustainable development.
Kalle has been a great role model for many of us with his never-ending energy and ability to enthuse. Kalle's door was always open, and he always took the time to talk, regardless of whether it was about Sandvik IK's latest match, or whether it was about solving differential equations. His scientific rigor, combined with his enthusiasm, has been crucial to many of us who got to know Kalle. It can be said without exaggeration that Kalle was the role model we had in the formation of CERE and what we wanted CERE to be. He is deeply missed by all of us, colleagues, former doctoral students and friends in Sweden and around the world.
Runar Brännlund

Foton: Juan Inda och Jenny Svennås-Gillner