AgriChar research group

What we do

Throughout the past two hundred years, the mankind has been emitting increasing amounts of greenhouse gases to the atmosphere and by doing so, likely contributing to the climate change. CO2 is considered to be the most important of the greenhouse gases and new ways to sequester it from the atmosphere are actively looked for. One of the most promising options worldwide for managing the CO2 is to develop sustainable biochar systems. Mixing biomass that has gone through a pyrolysis process, to soil might lead us even to a carbon-negative agriculture. Such a practice is especially promising if taken into account that biochars hold carbon in the soil for hundreds and even thousands of years.

In addition to that, auxiliary effects from adding some biochars to soil might further reduce greenhouse gas emissions as well as bring along desired effects to the environment. These effects include reductions in the fertilizer need by increased nutrient uptake efficiencies, improved soil physical structure as well as decreased nutrient leaching from the fields.

On the other hand, as the biochars once applied to the soils cannot practically be removed from the soil, the question: are they safe? needs to be answered before the practice could be widely adopted. Some of the most crucial gaps in the current scientific understanding of the functioning of biochars in soil and environment and its role for plants are due to the lack of data on:

   i. the long-term (i.e. more than 3 years) effects under field conditions on soil and plant properties;
   ii. studies under boreal conditions;
   iii. the biochar effects on soil biota under field conditions
   iv. changes occurring on the biochar surfaces.

Our research group targets these gaps focusing mainly on the effects of biochar systems on the physico-chemical properties of soil, on soil biota and on the yield formation and nutrition of field crops.

We have also ongoing projects in the areas of, among others, using biochar for re-using the phosphorus in lake sediments and reed and developing tailored biochar systems solutions for interested parties.

Since the start of the biochar research in University of Helsinki in 2010, we have also gained notable know-how in characterization methods of biochars: an expertise and knowledge that we are happy to share!

Group members 

The group is led by 
adjunct professor & principal investigator Dr. Priit Tammeorg
ResearcherID I Google Scholar I ResearchGate I TUHAT

Priit is interested in solutions increasing the sustainability of agriculture: nutrient recycling, soil fertility, organic farming and biochar. The main focus of his doctoral thesis was to study the effects of biochar use as a soil amendment on soil fertility, earthworms and plant properties in boreal soils. His current work as a PI of the AgriChar group continues along these lines and is focused on exploring the mechanisms of the short and long-term effects of biochar in boreal soils as well as novel ways to recycle nutrients in the agriculture.


Doctoral student Mr. Biar Deng

Biar is doing a D.Sc. on soil fertility and crop yield improvement through inclusion of multipurpose trees (Acacia seyal.L) and biochar application in drylands agrosystems; case study South Sudan. Biar was a part of HEI ICI project; Landscape Management Planning and Training for the Environment in South Sudan (LAMPTESS) during 2009, 2011and 2012.

Doctoral student Mrs. Mina Kiani

Mina is a D.Sc student in Agroecology at University of Helsinki and joined the AgriChar group in 2017. She is interested in finding solutions for closing the nutrient leakage from the cycle via reusing lake sediments in agriculture and landscape engineering. Her current research focuses on comparing different ways of sediments applications to soil to examine nutrient retention in topsoil and to quantify their effects on environment and crops.

Doctoral student Mr. Jure Zrim

Jure is a D.Sc. student in Agroecology at University of Helsinki, who joined the AgriChar group already for his MSc thesis work in 2015. He is investigating the effects of biochars and recycled organic fertilizers on soil biota in Finnish boreal conditions. His study focuses on medium– and long–term effects of softwood biochars on earthworm and microbial compositions, physicochemical properties of soil and plant growth.

Doctoral student Mr. Subin Kalu

Subin is a doctoral student in Agroecology at University of Helsinki. He is interested in exploring environment friendly solutions. For his doctoral studies, he is focusing on the long-term effects of biochar for sustainable agriculture in boreal soils. His studies emphasizes on the effects of biochar on soil physico-chemical properties, greenhouse gas emissions, plant nutrient uptake as well as effects of field-aging on the various properties of biochar particles in long-term.

MSc. student Mr. Antti Ali-Lekkala


MSc. student Ms. Niina Välinen

MSc. student Ms. Aino Härkönen 

MSc. student Mr. Samuel Amoah

AgriChar group in summer 2018

We work in co-operation with several other researchers from the University of Helsinki:

Dr. Asko Simojoki
Dr. Petri Penttinen
Dr. Kristiina Karhu
Prof. Juha Helenius
Dr. Michael Starr  

Prof. Frederick Stoddard
Prof. Pirjo Mäkelä
Dr. Olga Tammeorg
Dr. Festus Anasonye
Prof. emer. Olavi Luukkanen
Doctoral student Mr. Jukka Kivelä

Former group members

Several MSc. theses have been successfully accomplished on the topic of biochar use: 

Katariina Hämäläinen (The effects of biochar on soil moisture and nutrient concentrations and yield
components of oat (Avena sativa L.) five years after application.)

 Heidi Hovi (Biochar effects in soil properties and on the yield and species composition of grass).
 Jure Zrim (Medium-term effects of biochars on earthworms in two contrasting soils in Southern Finland)
Stefano Caro (Aalto University, Thermochemical Valorization of Waste: Pyrolytic Conversion of Horse Manure)
Pierre Boivin (Plant uptake of biochar nutrients)
Alma Lehti (Effects of biochar on the yield and species composition of grass)
Juho Honkala (Effects of biochar on faba bean yield formation)
Tuure Parviainen (Effects of biochar on earthworms).
Heedo Lee (Availability of biochar-K to plants)
Tero Brandstaka (Effects of biochar on N dynamics)
Chen Xiaoyulong (Effects of biochar on turnip rape yield formation) 
Jarkko Hovi (Effects of biochar on soil particle stability and P-retention)
Chiara Pituello (Plant uptake of biochar nutrients) 
Johanna Muurinen (Assessment of biochar verification methodology)


University of Helsinki biochar research group works in co-operation with other institutions :


Our work has been written about in several Finnish national newspapers and magazines, including:
  1. Yliopistolehti, December 2010  
  2.  Energia ja Ympäristö, May 2011    
  3. Helsingin Sanomat, 22 May 2014
  4. Ekoelo, February 2015
  5. Puutarha & kauppa, 9 March 2017
  6. Farmi 4/2018
  7. Tekniikka & Talous 5October 2018


We are very grateful for the financial support that makes our work possible.

Our special thanks go to:
Ministry of Agriculture and Forestry of Finland
University of Helsinki
The Jenny and Antti Wihuri Foundation
The Finnish Cultural Foundation

Maj and Tor Nessling Foundation
Niemi Foundation
Olvi Foundation
Emil Aaltonen Foundation
August Johannes and Aino Tiura Agricultural Research Foundation


Please contact us by e-mail: priit . tammeorg (at)