Extensive within-canopy light gradients importantly affect the photosynthetic productivity of leaves in different canopy positions and lead to light-dependent increases in foliage photosynthetic capacity per area (A_A). However, the controls on A_A variations by changes in underlying traits are poorly known. We constructed an unprecedented worldwide database including 831 within-canopy gradients with standardized light estimates for 304 species belonging to major vascular plant functional types, and analyzed within-canopy variations in 12 key foliage structural, chemical and physiological traits by quantitative separation of the contributions of different traits to photosynthetic acclimation. Although the light-dependent increase in A_A is surprisingly similar in different plant functional types, they differ fundamentally in the share of the controls on A_A by constituent traits. Species with high rates of canopy development and leaf turnover, exhibiting highly dynamic light environments, actively change A_A by nitrogen reallocation among and partitioning within leaves. By contrast, species with slow leaf turnover exhibit a passive A_A acclimation response, primarily determined by the acclimation of leaf structure to growth light. This review emphasizes that different combinations of traits are responsible for within-canopy photosynthetic acclimation in different plant functional types, and solves an old enigma of the role of mass- vs area-based traits in vegetation acclimation.

Niinemets, Ü., Keenan, T. F. ja Hallik, L. 2014. Tansley review. A worldwide analysis of within-canopy variations in leaf structural, chemical and physiological traits across plant functional types, The New Phytologist: http://onlinelibrary.wiley.com/doi/10.1111/nph.13096/abstract

Programme

Programme

The Centre of Excellence in Environmental Adaptation ENVIRON invites everybody to participate on the seminar!

Aeg/Time: 27.01,  14.15-16.30
Koht/Place: Ravila 14A-1019 (Chemicum)

Ajakava/Programme:

14.15-14.55 Maido Remm (TÜ, invited guest, Head of the Centre of Excellence in Genomics) "From genome sequences to DNA-based diagnostic tests"
14.55-15.20 Teele Ligi (TÜ, PhD-student) "Characterisation of bacterial communities in soil and sediment of a created riverine wetland complex using high-throughput 16S rRNA amplicon sequencing"
15.20-15.35 paus (tee/kohv)
15.35-16.00 Ebe Merilo (TÜ, senior researcher)  "To open or close - stomatal responses of different species in controversial environment: results and perspectives."
16.00-16.25 Steffen Noe (EMÜ, senior researcher) ”SMEAR Estonia - growing science around a new infrastructure”

 
 Info: Tiia Kurvits (tiia.kurvitsemu.ee) & Liina Jakobson (liina.jakobsonut.ee)

Among PhD-thesis in field of bio- and environmental sciences was the third price (700 Euros) awarded to Zhihong Sun for the contestwork "Isoprene emission from Aspen (Populus sp.) in relation to environmental drivers", supervisor Professor Ülo Niinemets, Estonian University of Life Sciences).

Seminars 2013

Thursday, 10 October, 12.15, Lai Str 40-218

Josep Peñuelas "Walking from genes to biosphere for a better understanding of global change in terrestrial ecosystems". Prof. Josep Peñuelas Global Ecology Unit CREAF-CEAB-CSIC, Center for Ecological Research and Forestry Applications (CREAF) - National Research Council (CSIC), Barcelona

Albert Porcar-Castell "Optics of Photosynthesis: seasonal variation in leaf-level chlorophyll fluorescence and spectral reflectance". Dr. Albert Porcar-Castell Dosentti/Adjunct Professor Department of Forest Sciences University of Helsinki

Doctoral Summer School "Measurement Methods in Environmental Biology"

Seminars 2012/2013

Seminars 2011/2012