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Tartu, Estonia

The Estonian University of Life science , located in Tartu, Estonia, is the former Estonian Agricultural University, which was established in 1951 and renamed and restructured in November 2005.Eesti Maaülikool is, by its own claim, the only university in Estonia whose priorities in academic and research activities provide the sustainable development of natural resources necessary for the existence of Man as well as the preservation of heritage and habitat. The EMÜ is a centre of research and development in such fields as agriculture, forestry, animal science, veterinary science, rural life and economy, food science and environmentally friendly technologies. The university is a member of the BOVA university network.Teaching and research is carried out in five institutes: Institute of Agricultural and Environmental scienceInstitute of Veterinary Medicine and Animal scienceInstitute of Forestry and Rural EngineeringInstitute of TechnologyInstitute of Economics and Social science.In 2009, there were 4704 students at EMÜ. There were 983 employees, among them 228 lecturers and 159 researchers and senior researchers. Wikipedia.

Lang M.,Estonian University of Life Sciences
Remote Sensing of Environment | Year: 2014

The directional multispectral hybrid type forest radiative transfer model FRT by Kuusk and Nilson (2000) was compared using directional reflectance factor of high angular resolution measured over three mature hemiboreal forest stands in Estonia. The model systematically underestimated backward scattering even in the case of the best available input data, especially in coniferous stands. The measured BRF distribution could be reproduced if the spherical leaf angle distribution was replaced by erectophile in order to better model the angular dependence of gap fraction, and the Ross-Nilson area scattering phase function was replaced by significantly more asymmetric Henyey-Greenstein phase function. The limited amount of available data does not allow deciding how universal are the applied asymmetry parameter values. The asymmetry of the phase function may depend on the species composition, stand age, and site type. © 2014 Elsevier Inc. Source

Laanisto L.,Estonian University of Life Sciences | Hutchings M.J.,University of Sussex
Science | Year: 2015

Fraser et al. (Reports, 17 July 2015, p. 302) report that a hump-backed model describes the worldwide relationship between productivity and plant species richness in grassland communities. We reanalyze their data from a larger-scale perspective, using local species pool. This influences richness far more strongly than productivity, and, when this is taken into account, the hump-backed richness-productivity relationship disappears. Source

Niinemets U.,Estonian University of Life Sciences | Flexas J.,University of the Balearic Islands | Penuelas J.,Autonomous University of Barcelona
Trends in Ecology and Evolution | Year: 2011

Physical CO 2 diffusion from sub-stomatal cavities to the chloroplasts where photosynthesis takes place is an important limitation of photosynthesis largely neglected in research related to global climate change. This limitation is particularly important in leaves with robust structures such as evergreen sclerophylls. In these leaves, photosynthesis is less sensitive to changes in stomatal openness, which is considered to be the primary limitation of photosynthesis. In this review we state that, because of large limitations in internal diffusion in C 3 plants, photosynthesis and the intrinsic efficiency of the use of plant water responds more strongly to elevated levels of CO 2 in leaves with more robust structures. This provides an additional explanation for the current apparent expansion of evergreen sclerophylls in many Earth ecosystems, and adds a new perspective to research of the biological effects of increasing atmospheric CO 2. © 2010 Elsevier Ltd. Source

Arneth A.,Lund University | Niinemets U.,Estonian University of Life Sciences
Trends in Plant Science | Year: 2010

Climate-herbivory interactions have been largely debated vis-à-vis ecosystem carbon sequestration. However, invertebrate herbivores also modify emissions of plant biogenic volatile organic compounds (BVOCs). Over the shorter term, they do this by the induction of de novo synthesis of a plethora of compounds; but invertebrates also affect the relative proportions of constitutively BVOCs-emitting plants. Thus, invertebrate-BVOCs interactions have potentially important implications for air quality and climate. Insect outbreaks are expected to increase with warmer climate, but quantitative understanding of BVOCs-invertebrate ecology, climate connections and atmospheric feedback remain as yet elusive. Examination of these interactions requires a description of outbreaks in ecosystem models, combined with quantitative observations on leaf and ecosystem level. We review here recent advances and propose a strategy for inclusion of invertebrate-BVOCs relationships in terrestrial ecosystem models. © 2009 Elsevier Ltd. All rights reserved. Source

Lang M.,Estonian University of Life Sciences
Agricultural and Forest Meteorology | Year: 2014

A combined spectrometer-BRF sensor was developed and built at Tartu Observatory, Estonia. The BRF sensor records angular distribution of target radiance with high angular resolution in red or near-infrared spectral band in a plain selected with sensor orientation up to 70° zenith angles. Bidirectional reflectance factor (BRF) measurements on board a low flying helicopter over three mature forest stands in South-East Estonia - a birch stand, a spruce stand, and a pine stand - are reported. Airborne measurements are supported by extensive ground truth data which have been reported in separate publications. The measurements revealed that both the BRF values and the BRF shape depend on the forest type and wavelength. The asymmetry of reflectance factor in the principal plane is strong and the hot-spot shape is very sharp in coniferous stands in the red spectral band. Multiple scattering of radiation in the NIR spectral band smooths the angular distribution of forest BRF. The collected data allow to validate forest radiative transfer models. © 2013 Elsevier B.V. Source

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