City of Helsinki biochar seminar and updates from our biochar park Hiilipuisto

 Yesterday was really nice to meet up with colleagues from City of Helsinki, HSY, VTT, Aalto University and other institutions to hear updates of City of Helsinki path towards C neutrality via using biochars as constituents of growing media for grasses, meadows and trees- as well as in cleaning the stormwater. I knew there are around twenty biochar pilot sites around the city, but learned about five more sites that had no idea of so far! A lot is going on, and one really needs to try hard to catch up with everything that has been started. To my surprise, one stormwater catchment test site is even here in Viikki, and I had no idea about this, there's no information poster or stand next to it either. Thank you to Satu Talvio for inviting us all to city center for this nice seminar and let's hope the numerous pilots will also be followed up so conclusions can be made what biochar practices work and what not.

I was also happy to share updates from our follow-up project of biochar park HiiliPuisto, where all major Finnish growing media producers (BiHii, Biolan, Carbofex and Kiteen Mato ja Multa, HSY, Kekkilä and Tieluiska) came up with their best biochar-containing recipes back in 2019. After the trees were planted in 2020, as long as the watering was actively maintained, there were no much differences between the biochar and control treatments- but starting from 2022 after the watering ended, clear differences started to appear in biomass gains. As can be seen below, especially apples (Malus) and limes (Tilia) benefited from the extra moisture and macroporosity introduced by wood-made biochars, and the strongest effects were found in the treatments where biochar application rates  were highest (even up to 25% (vol).  On the contrary, in structural soils, the added biochars did not show any effects on tree growth parameters within first four years.  We're looking forward to the longer-term effects, but will publish an intermediate report soon, meanwhile please have a look at our policy brief on general principles of such C parks: (https://www.frontiersin.org/articles/10.3389/fenvs.2021.672468/full)! Thank you to our dream team Topi Kopakkala, Dr. Anu Riikonen, Esko Salo, Mikko Jalas, Shiromi Samiraja, Sharifa Nabavi, Camille Michel, Philibert Henniaux and Guilhem Franque! The Carbon Lane project was funded by EIT Climate-KIC and the first follow-up project of the park, Hiilipuisto, by Maiju ja Yrjö Rikalan Puutarhasäätiö.

Seminar of our visiting post-doc researcher Subin Kalu

Long time no see!

Past weeks we had numerous meetings, lunches and dinners to catch up with Dr. Subin Kalu, who was visiting us first time over two years. After he defended his doctoral degree in Helsinki, since 2023, he has been intensively working in North Carolina State University, USA, and doing some fascinating fundamental science about destabilization of soil carbon after saltwater intrusion in coastal agricultural soils, and as one of the articles of that field was recently published (see here), we had chances to discuss these and other insights from Subin in more detail in our research group seminar. Naturally, we progressed also the numerous articles we're currently collaborating with Subin, about biochar and lake sediment recycling research, and had chance to visit the labs and greenhouses. In the latter, MSc student groups of Department of Agricultural Sciences are currently setting up their own practical experiments on nutrient recycling, cold and hot stresses of plants. Was nice meeting up- and hopefully we'll see soon again!