The optical signals of photosynthesis and their link to leaf, plant and ecosystem processes

  • +358 (0)2 941 58155
  • joan.porcar [at] helsinki.fi
  • Viikki, B building room 312
  • ORCID: 
  • More information in research database TUHAT, and the page of Optics of Photosynthesis Lab

Transport processes, freezing, embolism

My research is on tree structure and function, especially on transport processes within the tree and on the challenges these processes face in different environments. My special interest is on freezing behavior of wood.

 

Ecosystem ecology, physical limnology

  • +358 (0)294120340
  • Lahti, Niemenkatu 73, room 150

  • ORCID: 
  • More information in research database TUHAT

Urban trees, soils and ecosystems, and urban ecosystem services.

Photosynthesis, gas exchanges, remote sensing

My background is on plant physiology and light, and my research has been focused on characterising temporal dynamics in biochemical and biophysical mechanisms in leaves of boreal trees that uncouple remotely sensed data from photosynthetic gas exchange.

Atmosphere-biosphere interactions, planetary boundary layer oxidation processes, emissions of biogenic volatile organic compounds, boreal ecosystem

My main research topic is to investigate the drivers of both induced and constitutive production and emission of biogenic volatile organic compounds from trees and forest floor and how these emissions influence the chemical composition of the atmosphere. It is very important to study these aspects, since biogenic volatile organic compounds influence atmospheric aerosol formation and growth in forested areas and thus contribute to climate change

  • +358-503185704
  • Hyytiälä forestry field station, Hyytiäläntie 124, 35500 Korkeakoski, Finland
  • ORCID: 0000-0002-2023-2461
  • More information in research database TUHAT

Phytoplankton ecology and nutrient, biomolecule and gas cycling

My research interests are in the microscopical-sized life forms of lakes, especially in phytoplankton, and their roles in aquatic food webs. Particularly I’m interested in mixotrophy, grazing and exudate release (e.g. volatile organic compounds, BVOC’s) which are closely related to nutrient, biomolecule and gas cycling. My previous research topics have included studies on phytoplankton community composition and primary production as well as using phytoplankton as a potential source of oil for biodiesel production.

My research focuses on the general areas of forest ecosystem ecology and the impacts of climate change on forests. My area of expertize is process-based modelling of forest ecosystems. I'm currently focusing on the implementation of modern computational methods for the calibration and comparison of process-based models rich in parameters. I'm striving to apply Bayesian statistics to process based models, as a method for uncertainty analysis and model comparison. In the last years I also focused my research on the topic of water stress and water stress induced tree mortality.

Passive remote sensing, modeling, vegetation dynamics, spectroscopy, photosynthesis, wildfires

Developing a model that will help to interpret passive remote sensing signals of forests. The relationship between remote sensing signals and photosynthetic efficiency is complicated and non-linear. Mechanistic models can help to explain the underlying physiological and physical causes of remote sensing observations and provide a robust platform for the use of such signals in estimating carbon fixation rates.

 

Gas exchange, BVOCs, tree growth, measurement methodology, technical development, boreal forests

Long term measurements of tree and forest floor gas exchange, including VOCs, using online measurement methods. Understanding the dynamics, dependency on environmental controls of gas exchange, especially VOCs.

  • +358 50 415 6759
  • SMEAR II, Hyytiälä forestry field station, Hyytiäläntie 124, 35500 Korkeakoski, Finland
  • ORCID: 0000-0002-5686-1366
  • More information in research database TUHAT

Soil, carbon and nitrogen cycling, microbiology and chemistry

My major research interest is carbon cycling in forest and agricultural soils and the role of mycorrhizal fungi in belowground carbon dynamics. In addition, I am interested in the enzymes as well as other metabolites (VOC-compounds, bioactive compounds, microbial litter) produced by fungi. I use microbiological, chemical and isotopic (13C, 15N, 14C) methods in my work, and currently collaborate tightly with soil C modelers in order to incorporate novel experimental data into models for better model predictions on soil C pools. My earlier projects include studies on fungal bioremediation and biodiversity.

  • +358 (0)2 941 59318
  • Department of Forest Sciences, Latokartanonkaari 7, 00014 Helsingin yliopisto, B-building room 427 / Finnish Meteorological institute, Climate System Research, Erik Palménin aukio 1, 00560 Helsinki, Dynamicum, room 3C01a
  • ORCID: 0000-0001-8516-1388
  • More information in research database TUHAT and Nitrofungi and Pyrofungi project page

Carbon dynamics in forest soils, with special interest in disturbed (fire, wind, reindeer grazing, etc.) areas

My current projects include measuring the short and long term effects of forest fires on the stability of carbon pools in boreal forests, estimating carbon turnover on disturbed forest areas and studying the carbon neutrality of reindeer management.

Carbon cycle in northern forests

Nowadays, my main focus is in the carbon below ground i.e. in soil carbon and tree roots but I also have a special interest also in photosynthesis and in tree growth.

  • Kumpula, Finnish Meteorological Institute / Viikki, B building room 312
  • ORCID: 0000-0003-1775-8240
  • More information in research database TUHAT

Gas-phase nitrogen exchange, methane emissions, wetlands

Exchange of reactive gas-phase nitrogen compounds between atmosphere and vegetation and global modelling of methane emissions from wetlands.

  • +358 (0)2 941 51658
  • Kumpula, Dynamicum room D113
  • ORCID:
  • More information in research database TUHAT

Research infrastructures: Global SMEAR, SMEAR concept, eLTER, ACTRIS

Terrestrial ecology, biogeochemistry of air-land interactions, ozone deposition, ozone scavenging 

I have studied primarily ozone deposition to vegetation and the mechanisms behind the process and currently I am interested in the potential role of BVOCs and aerosol load in ozone scavenging. I am also involved in research on C and N cycling in high-mountain pastures in the Pyrenees, studying the role of plant diversity

Tree growth, carbon balance, carbon sink – source interactions

Climate change, Ecosystem services, Ecosystem water-balance, Plant-water relations, Tree growth

 

  • +358 504489485
  • ashraful.alam [at] helsinki.fi
  • Kumpula, Physicum
  • ORCID: 
  • More information in research database TUHAT

Carbon cycling, interactions between ecosystems

Environmental research infrastructures 

My research interests are in carbon cycling in different ecosystem and especially between them. After finishing a postdoc related to CO2 and CH4 emissions from lakes and small rivers in Canada, I'm back at the department of Forest Sciences. Now I'm working more to create conditions for research than with research itself. I am involved in the long-term ecosystem research infrastructures both at national (FinLTSER, INAR RI Ecosystems) and at international (eLTER) level.

Tree ecophysiology, growth dynamics, climate change, phenology

My research focus has been to link tree growth with other tree processes and its environment. This includes a closer examination of tree and water interaction, stem CO2 respiration and photosynthesis.

Currently, my work is to characterize atmospheric aerosols in urban megacities, and understand its implications to human health.

Energy exchange, dissolved organic carbon, DOC production, boreal forest

I am interested in how phenology affects the processes related to energy exchange and how ecosystems differ in this respect.

In addition I model the production of DOC (Dissolved Organic Carbon) and its transport into stream water in a boreal forest. In developing the model, I use data collected from intensively researched catchments in Finland and Sweden. I am also interested in the biogeochemical processes linked to the DOC cycle and have done reserach on the role of photochemistry in the breakdown of DOC transported by big rivers.

Water and carbon relations in tree, tree ecophysiology and ecology

My research focus on water and carbon fluxes in trees and between trees and the atmosphere, what are the processes regulating those fluxes, how they are influenced by the environment and how this response affect the trees. In particular, I am interested in the effect of drought. Beyond the individual level, I study how tree ecophysiology and fluxes: 1) impact biogeochemical cycles in forest ecosystems, and 2) how they respond to and shape tree ecology.