Zannatul's study presented at EGU in Vienna: Effects of nutrient-loaded biochar on biological nitrogen fixation in faba beans

 

Our doctoral researcher, Zannatul Ferdous, represented our research group at the EGU General Assembly 2025 with a poster presentation titled “The effects of nutrient-loaded biochar on biological nitrogen fixation in faba beans” (link to the abstract is here). This is the first time in the boreal region that the effect of nutrient-activated biochar and fertilisers on faba beans has been investigated and we see some interesting patterns. A follow-up greenhouse pot experiment will be conducted this summer. This is a part of Zannatul’s doctoral thesis, where she is investigating how nutrient-loaded biochars affect soil biota and nitrogen use efficiency by improving retention and reducing losses in boreal soils. This project was supported by the Niemi Foundation and Maa- ja Vesitekniikan Tuki, but also Tiina and Antti Herlin foundation.

 

We are grateful to the experts who guided this project to reach the stage of disseminating Dr. Kristiina Karhu, Dr. Frederick Stoddard, and Dr. Priit Tammeorg. Additionally, thanks to fellow colleagues Samuel Amoah, Karel Bartoš, Faiza Binte Enam for their cooperation. Special thanks to the Doctoral School of the University of Helsinki for awarding a travel grant to support Zannatul’s participation in EGU 2025!

AgriChar team updates: welcome new PhD student Franco and other new members; research seminar of Maryam

 This spring we have numerous new team members starting and we recently also celebrated the research visit of Maryam. Maryam is a PhD student at Ferdowsi University of Mashhad, Iran, and she was visiting researcher in our AgriChar research group projects since last September. During this research visit we collaborated on research on both short and long-term effects of biochars on soils, agricultural crops and nutrient recycling studies.  Furthermore, in the last part of her visit she participated in analysing the cranberry project samples for nutrient content analyses. In the research seminar, she presented us the results from her visit here but shared insights also from her PhD project on "Effects of green (Eucalyptus sp. leaves) synthesized iron oxide phyto-nanoparticles  and soil chemical factors on the behavior of Pb, Cd and Ni heavy metals in soils contaminated to total petroleum hydrocarbon  and their uptake by grasses."

Thank you for your time with us Maryam and let's stay in touch regarding future research collaboration!

We are also happy to announce the beginning of a new PhD research project of Franco, who started this spring in the international EU Horizon Ferro-project focusing on sustainable lake restoration. His research explores innovative approaches to lake remediation by integrating sediment removal with nutrient recycling for sustainable agriculture. Franco investigates how nutrient-rich sediments can be reused as phosphorus (P) fertilizer, addressing both eutrophication and the challenge of finite P resources (main supervisor Associate Prof. Olga Tammeorg). Welcome Franco on board!

 

 Furthermore, we are lucky to have several new MSc students, research assistants and interns joining us on finding out the effects nutrient-enhanced biochars have on greenhouse gas emissions from the soils as well as on the crop nutrient uptake and yield formation! Warm welcome to Sofi Paatelma, Ngoc Nguyen, Jenni Kurvonen, Tharangi Disnika and Anna Välkki! Dream team indeed to join Samuel, Zannatul and Zhouyang in our long-term biochar field experiments this growing season 2025!

 

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!