Estonian University of Life Sciences

www.emu.ee
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.


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News Article | December 19, 2016
Site: www.eurekalert.org

A new study led by a research scientist at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) highlights a literally shady practice in plant science that has in some cases underestimated plants' rate of growth and photosynthesis, among other traits. The study, published Dec. 19 in Nature Plants, suggests that this problem may stem from a common tendency in fieldwork to report leaf measurements taken in partially shaded conditions as existing in more fully sunlit conditions. As a result, global plant databases and models may require updating to better account for plant responses to full-sun conditions, said Trevor F. Keenan, a research scientist in Berkeley Lab's Earth and Environmental Sciences Area who led the study. "Often when researchers are in the field, it's hard to get to leaves at the top of trees," Keenan said, particularly in densely vegetated areas such as tropical forests where the canopies can reach over 100 feet in height. "In other cases, understory plants grow mostly in the shade, so it is impossible to sample in full sun. Traits vary quite a lot in the canopy, so if you don't sample from the top all of your samples will be biased," he said. In plant fieldwork, full-sun conditions are defined as those in which a plant receives the maximum amount of sunlight, typically at the top of a canopy, but most leaves do not grow in full-sun conditions. Leaves at the bottom of the canopy in a tropical rainforest may receive 100 times less sunlight than those at the top of the canopy, Keenan said. And many leaf characteristics -- which are integral to vital leaf functions such as carbon uptake and photosynthesis -- can vary 20-fold between the top and bottom leaves on the same plant. "For example, the highest concentration in nitrogen is at the top, where you have the most sunlight. Plants allocate a lot of nutrients there so they can 'profit' from it the most," Keenan said. Keenan and U?lo Niinemets, a researcher from the Estonian University of Life Sciences and Estonian Academy of Sciences, evaluated leaf data from several databases -- covering hundreds of plant species and spanning most regions of the world -- in the latest study. They used data from those studies that reported extra information about the specific location of the sampled leaves in the canopy as a benchmark for other studies' data. The research was conducted as Keenan and colleagues were assembling a new global database for plant research. The misreported sun vs. shade conditions are likely most pronounced in tropical regions, Keenan said. Because these regions of tropical vegetation are also considered to be the planet's largest "carbon sinks" in removing carbon dioxide from the atmosphere, "These are some of the most important areas to focus on," he said. Better accounting of light conditions that sampled leaves are growing in could help to improve models that account for plants' total rate of photosynthesis and better quantify their role as a carbon sink, for example, and for plants' adaptability to changing conditions. It can also identify important correlations between which plant traits are most pronounced under different lighting conditions. More accurate sampling methods can ultimately help improve scientists' understanding of whole ecosystem structure and function, and to understand how plants respond to factors such as climate change, the study states. In addition to improved reporting of sunlit conditions, there is also a need for better accounting of plant ages in field studies, as age may affect leaf chemistry and function, according to the study. The study concludes that field studies must take more care in accurately reporting sunlit vs. shaded conditions and age-driven trait responses in leaves. "These results will hopefully help to improve field measurement strategies," Keenan said. More standardized fieldwork, in parallel with new computational tools and theoretical work, will contribute to better global plant models, Keenan said. Researchers will likely tap the supercomputing capabilities of Berkeley Lab's National Energy Research Scientific Computing Center (NERSC) in upcoming modeling work. "We really don't know how plants are going to acclimate to a changing climate," Keenan said, noting that Lab researchers are developing a theory for why plants acclimate and change their allocations of nutrients within the canopy. "We can use this to better understand why trait values vary." New techniques are emerging to improve data collection in the field, Keenan also said. The study notes that some field research has used a shotgun approach to sample leaves at the top of the canopy -- firing a shotgun to clip off leaves that are otherwise out of reach -- though this technique alters the water flow that exists in attached leaves, so it can affect photosynthesis measurements. LIDAR, a laser-based mapping technology, has found more use in plant field work, Keenan noted, by providing 3-D images of forest structure, for example, and physics-based computer simulations are improving in their ability to model how leaves transfer energy from sunlight. "There is definitely a path forward in technological and scientific advances, along with new measurement approaches," he said. "There is a lot of work to be done." NERSC is a DOE Office of Science User Facility. This work was supported by Berkeley Lab's Laboratory Directed Research and Development fund and by DOE's Office of Science. Lawrence Berkeley National Laboratory addresses the world's most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab's scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy's Office of Science. For more, visit http://www. . DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.


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.


Pussa T.,Estonian University of Life Sciences
Meat Science | Year: 2013

Meat is a very complex and continuously changing ex vivo system of various high- and low-molecular substances that can be used for satisfying needs of the human organism for metabolic energy, building material and fulfilling of the other vital functions. A great majority of these substances are useful and safe for the consumer. Yet, meat and meat products may always contain substances exerting detrimental effects to the consumer's organism. The present paper is a literature review of the most important potentially toxic substances found in meat and meat products; their classification, ways of getting into the meat or formation during meat processing, undesirable physiological outcomes and biochemical mechanisms of their toxic effects, and methods for reduction of these responses. © 2013 Elsevier Ltd.


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.


Forest trees are exposed to a myriad of single and combined stresses with varying strength and duration throughout their lifetime, and many of the simultaneous and successive stress factors strongly interact. While much progress has been achieved in understanding the effects of single stresses on tree performance, multiple interacting stress effects cannot be adequately assessed from combination of single factor analyses. In particular, global change brings about novel combinations of severity and timing of different stresses, the effects of which on tree performance are currently hard to predict. Furthermore, the combinations of stresses commonly sustained by trees change during tree ontogeny. In addition, tree photosynthesis and growth rates decline with increasing tree age and size, while support biomass in roots, stem and branches accumulates and the concentrations of non-structural carbohydrates increase, collectively resulting in an enhancement of non-structural carbon pools. In this review, tree physiological responses to key environmental stress factors and their combinations are analyzed from seedlings to mature trees. The key conclusions of this analysis are that combined stresses can influence survival of large trees even more than chronic exposure to a single predictable stress such as drought. In addition, tree tolerance to many environmental stresses increases throughout the ontogeny as the result of accumulation of non-structural carbon pools, implying major change in sensing, response and acclimation to single and multiple stresses in trees of different size and age. © 2010 Elsevier B.V.


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.


Viidalepp J.,Estonian University of Life Sciences
Zootaxa | Year: 2011

Tribes of looper moths (Geometridae: Larentiinae) are reviewed. The tribe Dyspteridini Hulst is reinstated (previously synonymous with the Trichopterygini Warren). A new subtribe, Aplocerina, is separated from the Chesiadini Pierce, and the group Ortholithinae Pierce is dealt with as Scotopterygini Warren, the sister taxon to Xanthorhoini. Morphological traits for 22 of 23 larentiine tribes represented in the Holarctic fauna are listed and illustrated. A taxonomy of the subfamily Larentiinae is proposed and supported, using morphological data based on chemical communication structures and male genitalia. A new combination is presented: Melanthia mandshuricata (Bremer), transferred from Mesoleuca Hübner (Lar-entiini).


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

Plant-generated volatile organic compounds (BVOCs) play key roles in large-scale atmospheric processes and serve the plants as important defense and signal molecules. The main emphasis in quantitative BVOC studies has been on constitutive emissions of isoprene and specific monoterpene species that are present in only certain emitting plant species. However, environmental and biotic stresses can induce emissions of an array of organic compounds in any plant species, whereas the magnitude of emissions induced by given stress depends on stress tolerance, timing, duration and severity (mild versus strong) of the stress. The main view put forward in this review is that quantitative understanding of stress effects is the key for constructing realistic models of both constitutive and induced BVOC emissions. © 2009 Elsevier Ltd. All rights reserved.


Changes in the efficiency of light interception and in the costs for light harvesting along the light gradients from the top of the plant canopy to the bottom are the major means by which efficient light harvesting is achieved in ecosystems. In the current review analysis, leaf, shoot and canopy level determinants of plant light harvesting, the light-driven plasticity in key traits altering light harvesting, and variations among different plant functional types and between species of different shade tolerance are analyzed. In addition, plant age- and size-dependent alterations in light harvesting efficiency are also examined. At the leaf level, the variations in light harvesting are driven by alterations in leaf chlorophyll content modifies the fraction of incident light harvested by given leaf area, and in leaf dry mass per unit area (MA) that determines the amount of leaf area formed with certain fraction of plant biomass in the leaves. In needle-leaved species with complex foliage cross-section, the degree of foliage surface exposure also depends on the leaf total-to-projected surface area ratio. At the shoot scale, foliage inclination angle distribution and foliage spatial aggregation are the major determinants of light harvesting, while at the canopy scale, branching frequency, foliage distribution and biomass allocation to leaves (FL) modify light harvesting significantly. FL decreases with increasing plant size from herbs to shrubs to trees due to progressively larger support costs in plant functional types with greater stature. Among trees, FL and stand leaf area index scale positively with foliage longevity. Plant traits altering light harvesting have a large potential to adjust to light availability. Chlorophyll per mass increases, while MA, foliage inclination from the horizontal and degree of spatial aggregation decrease with decreasing light availability. In addition, branching frequency decreases and canopies become flatter in lower light. All these plastic modifications greatly enhance light harvesting in low light. Species with greater shade tolerance typically form a more extensive canopy by having lower MA in deciduous species and enhanced leaf longevity in evergreens. In addition, young plants of shade tolerators commonly have less strongly aggregated foliage and flatter canopies, while in adult plants partly exposed to high light, higher shade tolerance of foliage allows the shade tolerators to maintain more leaf layers, resulting in extended crowns. Within a given plant functional type, increases in plant age and size result in increases in MA, reductions in FL and increases in foliage aggregation, thereby reducing plant leaf area index and the efficiency of light harvesting. Such dynamic modifications in plant light harvesting play a key role in stand development and productivity. Overall, the current review analysis demonstrates that a suite of chemical and architectural traits at various scales and their plasticity drive plant light harvesting efficiency. Enhanced light harvesting can be achieved by various combinations of traits, and these suites of traits vary during plant ontogeny. © 2010 The Ecological Society of Japan.


News Article | December 19, 2016
Site: phys.org

The study, published Dec. 19 in Nature Plants, suggests that this problem may stem from a common tendency in fieldwork to report leaf measurements taken in partially shaded conditions as existing in more fully sunlit conditions. As a result, global plant databases and models may require updating to better account for plant responses to full-sun conditions, said Trevor F. Keenan, a research scientist in Berkeley Lab's Earth and Environmental Sciences Area who led the study. "Often when researchers are in the field, it's hard to get to leaves at the top of trees," Keenan said, particularly in densely vegetated areas such as tropical forests where the canopies can reach over 100 feet in height. "In other cases, understory plants grow mostly in the shade, so it is impossible to sample in full sun. Traits vary quite a lot in the canopy, so if you don't sample from the top all of your samples will be biased," he said. In plant fieldwork, full-sun conditions are defined as those in which a plant receives the maximum amount of sunlight, typically at the top of a canopy, but most leaves do not grow in full-sun conditions. Leaves at the bottom of the canopy in a tropical rainforest may receive 100 times less sunlight than those at the top of the canopy, Keenan said. And many leaf characteristics—which are integral to vital leaf functions such as carbon uptake and photosynthesis—can vary 20-fold between the top and bottom leaves on the same plant. "For example, the highest concentration in nitrogen is at the top, where you have the most sunlight. Plants allocate a lot of nutrients there so they can 'profit' from it the most," Keenan said. Cutting to the root of a data problem Keenan and U?lo Niinemets, a researcher from the Estonian University of Life Sciences and Estonian Academy of Sciences, evaluated leaf data from several databases—covering hundreds of plant species and spanning most regions of the world—in the latest study. They used data from those studies that reported extra information about the specific location of the sampled leaves in the canopy as a benchmark for other studies' data. The research was conducted as Keenan and colleagues were assembling a new global database for plant research. The misreported sun vs. shade conditions are likely most pronounced in tropical regions, Keenan said. Because these regions of tropical vegetation are also considered to be the planet's largest "carbon sinks" in removing carbon dioxide from the atmosphere, "These are some of the most important areas to focus on," he said. Better accounting of light conditions that sampled leaves are growing in could help to improve models that account for plants' total rate of photosynthesis and better quantify their role as a carbon sink, for example, and for plants' adaptability to changing conditions. It can also identify important correlations between which plant traits are most pronounced under different lighting conditions. More accurate sampling methods can ultimately help improve scientists' understanding of whole ecosystem structure and function, and to understand how plants respond to factors such as climate change, the study states. In addition to improved reporting of sunlit conditions, there is also a need for better accounting of plant ages in field studies, as age may affect leaf chemistry and function, according to the study. The study concludes that field studies must take more care in accurately reporting sunlit vs. shaded conditions and age-driven trait responses in leaves. "These results will hopefully help to improve field measurement strategies," Keenan said. More standardized fieldwork, in parallel with new computational tools and theoretical work, will contribute to better global plant models, Keenan said. Researchers will likely tap the supercomputing capabilities of Berkeley Lab's National Energy Research Scientific Computing Center (NERSC) in upcoming modeling work. "We really don't know how plants are going to acclimate to a changing climate," Keenan said, noting that Lab researchers are developing a theory for why plants acclimate and change their allocations of nutrients within the canopy. "We can use this to better understand why trait values vary." New techniques are emerging to improve data collection in the field, Keenan also said. The study notes that some field research has used a shotgun approach to sample leaves at the top of the canopy—firing a shotgun to clip off leaves that are otherwise out of reach—though this technique alters the water flow that exists in attached leaves, so it can affect photosynthesis measurements. LIDAR, a laser-based mapping technology, has found more use in plant field work, Keenan noted, by providing 3-D images of forest structure, for example, and physics-based computer simulations are improving in their ability to model how leaves transfer energy from sunlight. "There is definitely a path forward in technological and scientific advances, along with new measurement approaches," he said. "There is a lot of work to be done." Explore further: Soybean plants with fewer leaves yield more

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