![Kajar Köster](https://uefconnect.uef.fi/wp-content/uploads/2022/08/99bfa5d87390337d848e00e8f686802c_profile_file-500x500.jpg)
Research interests: Disturbances (fire, wind, reindeer grazing, insects, etc.) and biogeochemistry, carbon dynamics, greenhouse gas emissions, pyrogenic matter formation and post-fire transport (by water), post-disturbance changes in biogeochemical processes, etc.
My research deals with questions how the northern ecosystems respond to climate change, the changes in land-use, and the changes in disturbance dynamics. My current research focusses on how northern ecosystems respond to changes in fire dynamics and other disturbances, and what are the consequences on the formation of greenhouse gas, volatile organic compound, pyrogenic carbon, and soot emissions. The research uses a wide scope of measurements with extensive field-based measurements including experimental and natural fires and detailed process-level studies on the effects of fires on the formation of particles using the existing laboratories in UEF. The work will link disturbance related studies to plant ecology, biogeochemistry and atmospheric sciences, and will improve predictions of ecosystem responses to a changing climate, and helps to understand possible tipping points in the environment (e.g. transitions of ecosystems from carbon sinks to carbon sources).
Tutkimusryhmät
Projektit
Julkaisut
22/22 kappaletta-
Enhancing boreal forest resilience: A four-year impact of biochar on soil quality and fungal communities
Liao, Yang-chun-zi; Pu, Hong-xiu; Jiao, Zi-wen; Palviainen, Marjo; Zhou, Xuan; Heinonsalo, Jussi; Berninger, Frank; Pumpanen, Jukka; Köster, Kajar; Sun, Hui. 2024. Microbiological research. 283: -
Organic soil greenhouse gas flux rates in hemiboreal old-growth Scots pine forests at different groundwater levels
Samariks, Valters; Kenina, Laura; Istenais, Nauris; Ozolins, Kristaps; Koster, Kajar; Jansons, Aris. 2024. European journal of forest research. [Epub ahead of print 25 April 2024]: 1-12 -
Post-fire soil carbon emission rates along boreal forest fire chronosequences in northwest Canada show significantly higher emission potentials from permafrost soils compared to non-permafrost soils
Köster, Kajar; Aaltonen, Heidi; Köster, Egle; Berninger, Frank; Pumpanen, Jukka. 2024. Frontiers in ecology and evolution. 2023; 11: . 1331018 -
Post-fire soil greenhouse gas fluxes in boreal Scots pine forests–Are they affected by surface fires with different severities?
Köster, Kajar; Kohli, Juliana; Lindberg, Henrik; Pumpanen, Jukka. 2024. Agricultural and forest meteorology. 349: -
Recovery and resilience of European temperate forests after large and severe disturbances
Cerioni, Matteo; Brabec, Marek; Bace, Radek; Baders, Endijs; Boncina, Andrej; Bruna, Josef; Checko, Ewa; Cordonnier, Thomas; de Koning, Johannes H. C.; Diaci, Jurij; Dobrowolska, Dorota; Dountchev, Alexander; Engelhart, Jeroen; Fidej, Gal; Fuhr, Marc; Garbarino, Matteo; Jansons, Aris; Keren, Srdjan; Kitenberga, Mara; Klopcic, Matija; Konopka, Bohdan; Kopecky, Martin; Koester, Kajar; Kucbel, Stanislav; Lacombe, Eric; Laurent, Lisa; Leyman, Anja; Lingua, Emanuele; Macek, Martin; Maciejewski, Zbign. 2024. Global change biology. 30: -
Spatial heterogeneity of soil respiration after prescribed burning in Pinus koraiensis forest in China
Wang, Jianyu; Ding, Yiyang; Köster, Kajar; Li, Fei; Dou, Xu; Li, Guangxin; Hu, Tongxin. 2024. Journal of environmental management. 368: . 122126 -
The complex composition of organic aerosols emitted during burning varies between Arctic and boreal peat
Schneider, Eric; Rüger, Christopher P; Chacón-Patiño, Martha L; Somero, Markus; Ruppel, Meri M; Ihalainen, Mika; Köster, Kajar; Sippula, Olli; Czech, Hendryk; Zimmermann, Ralf. 2024. Communications earth & environment. 5: . 137 -
The fate of remnant trees after wind disturbances in boreal and temperate forests
Palm-Hellenurm, Kristiina; Baders, Endijs; Frelich, Lee E; Koster, Kajar; Metslaid, Marek; Polyachenko, Olga; Seedre, Meelis; Shorohova, Ekaterina; Stanturf, John A; Vodde, Floortje; Jogiste, Kalev. 2024. Frontiers in forests and global change. 7: -
Temporal dynamics of soil dissolved organic carbon in temperate forest managed by prescribed burning in Northeast China
Dou, Xu; Ding, Yiyang; Köster, Kajar; Sun, Aobo; Li, Guangxin; Yue, Yang; Sun, Long; Hu, Tongxin. 2023. Environmental research. 237: -
The Center of Excellence in Atmospheric Science (2002–2019) — from molecular and biological processes to the global climate
Lintunen, Anna; Aalto, Juho; Asmi, Ari; Aurela, Mika; Bäck, Jaana; Ehn, Mikael; Ezhova, Ekaterina; Hakola, Hannele; Hartonen, Kari; Heinonsalo, Jussi; Hellén, Heidi; Hölttä, Teemu; Jokinen, Tuija; Järvi, Leena; Järvinen, Heikki; Kangasluoma, Juha; Kerminen, Veli Matti; Kolari, Pasi; Köster, Kajar; Köster, Egle; Kulmala, Liisa; Kurten, Theo; Laaksonen, Ari; Lappalainen, Hanna K.; Laurila, Tuomas; Lehtipalo, Katrianne; Lihavainen, Heikki; Lohila, Annalea; Losoi, Mari; Mäkelä, Annikki; Makkonen, Ri. 2023. Boreal environment research. 28: 15-80