EcolChange seminar on 16th of February – Marju Himma about communicating science

Seminar of the Centre of Excellence EcolChange

Researcher and PhD student of media and communication at University of Tartu and Editor in Chief of Estonian Public Broadcasting, Marju Himma, will give a talk titled:

Communicating science

Time: Thursday, 16. February 2017 at 15.15

Place: Tartu, Lai 40-218 (Vaga auditorium)

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Marju himma (on the left) doing her daily job of communicating science (pic from here)

Summary:

1) Triangulation of information between science, public sphere and policy makers. In the age of information/data overload the decision-making is getting more complex, which presents a challenge in communicating science in public and policy makers. Otherwise we face the situation of “alternative facts”, misleading information and poor decision making on all levels. One of the solutions in this situation is:

2) Empowerment of scientists and researchers in communication. I bring some examples where the voice of the scientists is essentially needed: Reaching the goal of 1 %of GDP in Estonian state budget was set in 2014, but in 2017 it was 0.86%; the transition of science and research into knowledge based society in Estonia is poor compared to e.g. Finland or other Scandinavian countries; people are making everyday decisions based on pseudo-scientific or fabricated information.

Advocacy is the buzzword we hear in political communication, journalism etc., but there are not too many examples in science and research. This places scientists in the position where their voice is less heard both in public and in the process of policy making. Therefore we need to empower scientists and researchers to communicate directly to public in order to change the previous examples.

3) In the light of the previous two statements I propose five practical suggestions for efficient science communication.

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New paper published – Community response to alkaline pollution as an adjusting re-assembly between alternative stable states

Text by Ave Suija and Jaan Liira
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The schematic representation of community adaptive responses on environmental changes, supported by meta-pool of species (fig by Jaan Liira)

Man made disturbances and environmental pollution are the reality of contemporary world, however, such long-term created environmental gradients are handy to describe ecological processes (community dynamics) otherwise difficult to observe in natural conditions or test in experiments. We assumed that at regional scale, many community responses should not be always interpreted as a degradation, but as a part of the long-term dynamic equilibrium of various community states, if they are supported by different environment-specific species pools, harboured in different habitats. At the regional scale, such spatially clustered pool system forms a meta-pool of species. A community degradation should be declared only when the meta-pool cannot support the community’s switching between alternate states. The difficulty in applied ecology relies in adequate delineation and evaluation of these alternate states – usually, expert knowledge or species niche data have been used, but their accuracy has been sometimes questioned. A different approach is to compare new community states to other communities in the region, as they harbour alternative species pools within meta-pool.

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Exteme pH of tree bark near the cement factory in Kunda, Estonia (pic by Jaan Liira)

We studied the re-assembly of lichen community on Scots pine (Pinus sylvestris) in response to the long-term alkaline dust pollution around a cement factory. Along pollution gradient we observed (1) the change of substrate (pine bark) pH from very acid to pH analogous to limestone, and (2) a respective alteration of natural community to unusual to pine lichen communities. The loss of diversity reflected the difference between source species pools. We found also that (3) expert knowledge (ecological indicator values) can reflect the overall trend, however, it does not describe humped variability of niche range of species, the divergence in alternate community states two different reference communities, add the revealed hidden interaction between limiting environmental drivers (specifically substrate pH and understorey density).

The study indicates that community responses to man-made disturbances should be interpreted with care, particularly as community reformations take long time assuming the availability of respective species sources. Still, as disturbance intensity may change over time by improving technologies or policies, such alterations can be reversed, if original pools are preserved somewhere in the neighbourhood.

Citation: Suija, A., & Liira, J. (2016). Community response to alkaline pollution as an adjusting reassembly between alternative stable states. Journal of Vegetation Science, DOI: 10.1111/jvs.12506 (link to full text)

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Exposed thick layer of accumulated cement dust inside the moss layer in Kunda, Estonia (pic by Jaan Liira)

Abstract:

Aims

We hypothesize that the community response to disturbances can be interpreted as a large-scale dynamic equilibrium between multiple alternate states stemming from different species pools within a regional meta-pool and being limited by species’ multi-dimensional niches. We explore this hypothesis by examining the re-assembly of an acidophilous lichen community in response to long-term alkaline dust pollution, assuming understorey as a potential side-factor.

Location

Around a cement factory in Kunda, Estonia.

Methods

Lichen communities on Scots pine (Pinus sylvestris) trunks in 40 stands around a cement factory and in nine distant limestone habitats were assessed.

Results

The formed bark pH gradient from pH 2.4 to 8.1 was reflected in a continuum of lichen communities on pines from acidophilous to basidophilous communities. Besides suppressing species richness, understorey density more evidently caused the compositional divergence from neutral bark conditions. The effect of hidden interactions among drivers was explained through reactions of individual species – almost all species across the pollution gradient were pH-limited, whereas species adapted to neutral or alkaline substrate were additionally sensitive to understorey conditions. The hump-shaped distribution of pH niche ranges along the observed niche optima, rather than ecological indicator values, showed that the shape of species’ multi-dimensional niche-space still needs to be quantified.

Conclusions

Each alternative community state along the disturbance gradient represents a realization of its specific species pool within the meta-pool. Degradation can be defined if the community state is not supported by a meta-pool. Species infiltration during community re-assembly can be predicted using species source communities as cost-efficient proxies.

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New paper published – Ecological theory provides strong support for habitat restoration

Text by Aveliina Helm

Habitat restoration needs to take recent scientific advances into account

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The involvement of ecological theory in practical habitat restoration has significantly increased in the past decade. However, there are still visible gaps between the advancing theoretical ecology and current practical approaches of habitat restoration. Insufficient knowledge flow between theoretical ecologists, restoration ecologists and practitioners does not allow to take full advantage of advancing ecological theory in restoration, possibly leading also to less successful restoration projects. Similarly, improved communication between restoration practitioners and theoretical ecologists can benefit ecological theory as restoration projects often offer great opportunities for testing theoretical approaches in the field. In this paper, we bridge these gaps between theory and practice by linking recent developments in plant ecology with the main questions every restoration practitioner should ask. We discuss ecological theories that 1) help to identify target species and baseline conditions in restoration; 2) allow to understand when one can count on spontaneous recovery and when are additional efforts required for facilitating dispersal of species; 3) are useful for determining factors that needs to be taken into account for successful establishment of target species; and 4) enable to estimate time-scale needed to consider for the evaluation of restoration success.

Recent advances in ecology that help to answer these questions involve species pool theory, landscape-scale dispersal patterns, species assembly rules and temporal delays in response to environmental disturbance (extinction debt and colonisation credit).

Citation: Török, P., & Helm, A. (2017). Ecological theory provides strong support for habitat restoration. Biological Conservation, 206, 85-91. (link to full text)

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One way to restore coastal meadow in an urban environment – “Urbancows” project in Pärnu, Estonia (pic from here)

Abstract:

The involvement of ecological theory in habitat restoration has significantly increased in the past decade. However, despite the fact that the field of restoration ecology has grown academically strong in recent years, there are still visible gaps between the advancing discipline of theoretical ecology and current approaches of habitat restoration. We propose bridging these gaps by linking recent developments in theoretical plant ecology with the main questions every restoration practitioner should ask, namely: Q1) How to identify target species and baseline conditions for restoration of the selected habitat?; Q2) When can one count on spontaneous dispersal and when are additional efforts required for facilitating dispersal of desired species?; Q3) Which factors determine the successful establishment of target species and assembly of target communities?; and Q4) What time-scale needs to be considered for the evaluation of species colonisation and restoration success? Knowledge and experience accumulated in practical restoration can considerably benefit theoretical ecology for example by improving the understanding on (i) temporal changes in community, (ii) species assembly, (iii) species dispersal and establishment and (iv) landscape-scale dynamics of biodiversity. We emphasise that to improve joint thinking of practical restoration and theoretical ecology, restoration-problem-driven theoretical research is necessary. We suggest either (i) to translate and link the current findings of theoretical ecology to restoration strategies; and/or (ii) to summarise practical restoration needs by formulation of questions and testable hypotheses based on theory.

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Attending conference – EcolChange in Oikos Finland

Text by Maarja Öpik and Lauri Laanisto

Oikos Finland held a conference in Helsinki from 31st January to 1st February to celebrate 100 years of Finnish ecology (link to conference home page). EcolChange was represented by Maarja Öpik who was invited to give a plenary lecture. She spoke about AM fungal species pools and dark diversity.

Conference was preceded by a symposium in memory of late academician Ilkka Hanski. Another EcolChange associate, Lauri Laanisto, was also attending the conference, especially because of Hanski´s symposium, as he is currently translating “Messages from the Islands” into Estonian.

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A little visit to Ateneum after the conference, Maarja with Akseli Gallen-Kallela´s Kullervo Cursing, 1899 (pic by Lauri Laanisto)

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EcolChange seminar on 16th of February – Marju Himma

Seminar of the Centre of Excellence EcolChange

Marju Himma will talk about disseminating scientific results for the wider audiences, about popularization of sciene.

Thursday, 16 February 2017 at 15:15, Tartu, Department of Botany of University of Tartu, Vaga auditorium (Lai 40217)

More information: Tiia Kurvits tiia.kurvits@emu.ee

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Marju Himma is the head of novaator.err.ee, which is the main science popularization portal in Estonia

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EcolChange-related conference – Woody Root 7

Dear Colleagues!

You are kindly invited to Woody Root 7 – 7th International Symposium on Physiological Processes in Roots of Woody Plants, to be held from June 26th till June 29th, 2017 in Tartu, Estonia.

The symposium will focus on traditional topics, such as water acquisition and nutrient uptake, root morphology and physiology and belowground assimilate allocation. In a rapidly changing world we will address also issues of roots in global change, linking root functioning and belowground biodiversity, root phenology, roots and ecosystem services. Moreover, living in the era of big data we address the need of understanding macroecological patterns, root traits, models and concepts.

Detailed information is available on our webpage (http://woodyroot7.ut.ee/)

I am happy to announce that online registration (early bird period till 30th of April) and abstract submission is open. Please note the deadline for Abstract submission is 15th of March.

We look forward welcoming you in Tartu.

Kind regards,

Ivika Ostonen, on behalf of the local and international organizing committees

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Woody roots in Alutaguse floodplain

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New paper published – Both spatiotemporal connectivity and habitat quality limit the immigration of forest plants into wooded corridors

Text by Taavi Paal and Jaan Liira

What limits forest plant migration along wooded corridors?

Europe’s natural forest is heavily fragmented by agricultural land. Such isolation threatens the long-term persistence of forest biodiversity. The concept of patch-corridor-matrix system suggests that isolated patches can be ecologically connected by a corridor network. As forest-specialist plants (termed also as “ancient forest plants”) are adapted to a stable forest environment and are considered to be poor long-distance dispersers, their use of wooded corridors hasn’t got much attention. We asked why? As in the long run even slowly dispersing species should eventually immigrate into corridors. Maybe the edge effect limits the establishment? Or is the positive expectation on the functionality of corridors driven by the response of habitat generalist species?

To avoid the early-successional underestimation of arrival success, we concentrated our study on older (>50 years) wooded corridors. The isolation effect was evaluated by sampling two types of corridors: directly connected to source forest and isolated mid-field corridors, and margins of ancient forests were used as a comparison habitat (as they are also prone to edge effects).

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Forest connecting alley near Vara, Estonia (pic by Taavi Paal)

Overall, forest generalists prevailed over a small number of forest specialists in wooded corridors. The connectivity/isolation effect ruled over the edge effect as the number of forest specialists in connected corridors was analogous to forest edges. The expectation of ineffective immigration was met only in isolated corridors which harboured a few forest specialists, but still many generalists. Tested in other terms, forest specialists depended on historical stability of the surrounding forest landscape, while forest generalists reflected the status of present-day landscape configuration. The poorly detected edge effect was probably suppressed by overall canopy closure of overstorey and the width of the corridor. In semi-open corridors forest specialists were outcompeted by open habitat plants.

What can be done in order to improve the environment of corridors for forest specialists? As forest specialists cannot cope with rapid changes in forest landscape configuration, wide corridors with suitable shaded conditions and directly connected to ancient forests should be maintained for many decades. Ecologically functioning of wooded corridors can be ensured with the width of at least two lines of mature trees and with overhanging side branches. Ground disturbances should also be kept to a minimum (e.g. ditch construction, frequent mowing) as they promote generalist species. However, as the formation of shade providing overstorey takes decades, historical alleys should be sustainably managed and their connectivity with forests should be improved.

 

Citation: Paal, T., Kütt, L., Lõhmus, K. & Liira, J. 2017. Both spatiotemporal connectivity and habitat quality limit the immigration of forest plants into wooded corridors. Plant Ecology (in press). doi: 10.1007/s11258-017-0700-7 (link to full text)

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Anemone nemorosa growing in an alley (pic by Taavi Paal)

Abstract:

Extensive afforestation of agricultural areas has increased the importance of green corridors as a dispersal network. We tested the effect of spatiotemporal connectivity, edge effect and habitat structural quality of wooded corridors on the long-term immigration success of forest specialist plants relative to the performance of forest generalists. In agricultural landscapes of central and southern Estonia, we sampled 28 historically connected and 52 isolated tree lines and alleys with a minimum age of 50 years, and 93 edges of ancient forests. The regional pool of common forest plants was compiled using species’ frequency data in 91 ancient forests. Both landscape connectivity and habitat quality affected the richness of response groups, but specialists and generalists responded to different drivers. Forest specialists required long-term neighbourhoods of ancient forest and benefited from a direct connection between forest and corridor. Habitat generalists reacted positively to the recently modified structure of the landscape. When a corridor was connected to forest, the dual edge in the corridor did not result in an increased negative edge effect on forest specialist arrival. Even if both specialists and generalists required wide corridors with optimum shade, forest specialists also benefited from mature overstorey and outward overhanging branches, whereas forest generalists used disturbance-created microhabitats. We conclude that only wooded corridors with long-term connectivity to seed source forests and widely branched tree canopies will function as a green infrastructure supporting forest-specific biodiversity.

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New paper published – Emissions of carotenoid cleavage products upon heat shock and mechanical wounding from a foliose lichen

Text by Lauri Laanisto

I like that this paper starts with a metaphor: “Chlorophyll (Chl) is a double-edged sword for plants.” Because “This molecule is capable of harvesting sunlight, initiating the process of photosynthesis, but it also involves an unavoidable risk of photooxidation.” Though I´m not sure whether this metaphor indeed holds water. The edges of this metaphoric sword seem to be awfully uneven. Especially because plants have developed pigments against it. And this paper tries to figure out which edge would cut the holder.

Another kind of curious aspect of this study is that while the whole Introduction part deals with vasular plants and how VCCPs (which are not defined in the paper so that I would actually understand what the acronym stands for) are stress regulated, the whole experiment was done with a lichen! The argument for that is: “We have chosen such a model and not a vascular plant to simplify the pathway between the thylakoids and the open atmosphere.” Is it really a substantial reason to make such a fundamental change in the study object? It´s a curious question…

Anyway, based on the results, the authors conclude that the presence of VCCPs could indicate the degradation process in caroteinoids. Whether the lichen was under heat stress or not. And in comparison with other volatiles, the emission rate of VCCPs had the lowest change. It went up just a little.

I kind of got the feeling that this paper represents the results of an experiment not going as expected. For example, the concluding paragraph reads as follows: “Overall, the present work shows that VCCPs are produced constitutively and released from the thalli of L. pulmonaria. However, although VCCP emissions from photosynthetic tissues might, potentially, serve similar functions as other well-recognized volatile infochemicals (LOX products, methyl salicylate, methyl jasmonate) that act as cues in biocommunication and plant signaling, low emission rates of VCCPs, and the absence of quantitative relationship with stress intensity, suggests that it is unlikely that these volatiles play such a role in the studied lichen species.”

Citation: García-Plazaola, J. I., Portillo-Estrada, M., Fernández-Marín, B., Kännaste, A., & Niinemets, Ü. (2017). Emissions of carotenoid cleavage products upon heat shock and mechanical wounding from a foliose lichen. Environmental and Experimental Botany, 133, 87-97. (link to full text)

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Lobaria pulmonaria (from Wikipedia)

Abstract:

Carotenoids constitute a major target of chloroplastic photooxidative reactions, leading to the formation of several oxidized derivatives and cleavage products, some of which are volatile (VCCPs). Among them, β-cyclocitral (β-CC), at least, is a retrograde signaling molecule that modulates the activity of many key physiological processes. In the present work, we aimed to study whether β-CC and other VCCPs are released into the atmosphere from photosynthetic tissues. To overcome stomatal limitations, the foliose chlorolichen Lobaria pulmonaria was used as the model system, and the emissions of biogenic volatiles, induced by heat and wounding stresses, were monitored by proton-transfer reaction time-of-flight mass-spectrometry (PTR-TOF-MS) and gas-chromatography (GC–MS). Prior to stress treatments, VCCPs were emitted constitutively, accounting for 1.3% of the total volatile release, with β-CC being the most abundant VCCP. Heat and wounding stresses induced a burst of volatile release, including VCCPs, and a loss of carotenoids. Under heat stress, the production of β-CC correlated positively with temperature. However the enhancement of production of VCCPs was the lowest among all the groups of volatiles analyzed. Given that the rates of carotenoid loss were three orders of magnitude higher than the release rates of VCCPs and that these compounds only represent a minor fraction in the blend of volatiles, it seems unlikely that VCCPs might represent a global stress signal capable of diffusing through the atmosphere to different neighboring individuals.

 

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New paper published – Selection of source material for introduction of the locally rare and threatened fern species Asplenium septentrionale

Text by Jaan Liira
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Asplenium septentrionale in nature (photo by Kai Rünk)

Forked spleenwort, Asplenium septentrionale, is a mainly petrophilous fern species in European mountains and rare on acidic siliceous rocks in lowland areas of the continent, where habitats are fragmented and populations isolated. In Estonia, the single extant population occupies a restricted area and is threatened by human disturbances. An introduction project of the species was prepared to estimate the potential to form new populations in new protected sites using ex-situ propagated young sporophytes as transplantation material, by comparing the recruitment biology of three different donor populations. First, we carried out a laboratory breeding experiment to evaluate the populations’ ability for intra-gametophytic selfing, and secondly, in a common garden estimated the fitness of offspring. The results showed that the only Estonian donor population showed very high capacity for intra-gametophytic selfing, as well as high rate of sporophytic mortality (83%), and these rates were comparable to one of two reference donor populations in Finland. However, plants of Estonian population were smaller, representing a unique locally adapted genotype. Therefore, it needs more efficient protection in its present location. We suggest that planting material for introduction into nearby new locations should be collected from the local population, as the best locally adapted. Only in the risk of severe environmental change and of extinction, several neighbouring populations could be pooled to maximise genetic diversity.

Citation: Rünk, K., Pihkva, K., Liira, J., & Zobel, K. (2016). Selection of source material for introduction of the locally rare and threatened fern species Asplenium septentrionale. Plant Ecology & Diversity, 9: 167-173 (link to full text)

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Asplenium in pot experiment (photo by Kai Rünk)

Abstract:

Background: Forked spleenwort, Asplenium septentrionale, is a mainly petrophilous fern species in European mountains and rare on acidic siliceous rocks in lowland areas of the continent, where habitats are fragmented and populations isolated. In Estonia, the single extant population is very small, occupies a restricted area and is threatened by human disturbances. An introduction project of the species was prepared to form new populations in new protected sites using ex-situ propagated young sporophytes as transplantation material.

Aims: To obtain data on the species recruitment population biology and provide context information for selecting donor plant material.

Methods: We sampled three regional/local donor populations. First, we carried out a laboratory breeding experiment to evaluate the populations’ ability for intra-gametophytic selfing. Second, to estimate differences in fitness of offspring among the populations, we grew young sporophyte plants in a pot experiment under controlled conditions in a common garden.

Results: The Estonian population showed very high capacity (90%) for intra-gametophytic selfing, as well as high rate of sporophytic mortality (83%), but the rates are comparable to one of the reference populations in Finland. However, plants of Estonian population were smaller.

Conclusions: The Estonian population may represent a unique pre-adapted or locally adapted genotype; therefore, it needs more efficient protection in its present location. Planting material for introduction should be collected from the local population, as the best locally adapted. Only in the risk of severe environmental change and of extinction, several neighbouring populations could be pooled to maximise genetic diversity.

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New paper published – Global leaf trait estimates biased due to plasticity in the shade

Text by Trevor Keenan

Our new paper, “Global leaf trait estimates biased due to plasticity in the shade” (link to full text) was published online in Nature Plants on December 19th. It highlights a literally shady issue in plant science that has in some cases led to the underestimation of plant rates of growth and photosynthesis, among other traits.

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The paper uses recent understanding of how leaf traits vary in response to light, along with a variety of global databases, to estimate trait values in fully sunlit conditions. It finds that a large proportion of trait values in current databases are significantly lower than our estimates, indicating that they were actually measured in the shade. As a result, global plant databases and models may require updating to better account for plant responses to full-sun conditions.

This issue may stem from a common tendency in fieldwork to report leaf measurements taken in partially shaded conditions as existing in more fully sunlit conditions. Often when researchers are in the field, it’s hard to get to leaves at the top of trees, 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.

 

Large light-dependent variations in leaf traits

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. 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.

 

Cutting to the root of a data problem

Together with Ülo Niinemets, we evaluated leaf data from several databases—covering hundreds of plant species and spanning most regions of the world. We 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 misreported sun vs. shade conditions are likely most pronounced in tropical regions. 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.

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.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.

We conclude that field studies must take more care in accurately reporting sunlit vs. shaded conditions and age-driven trait responses in leaves.

New techniques are emerging to improve data collection in the field. 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.

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LIDAR, a laser-based mapping technology, has found more use in plant field work, 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.

 

This blog post was adapted from the Lawrence Berkeley National Lab. News Center: http://newscenter.lbl.gov/2016/12/19/new-leaf-study-sheds-light-on-shady-past/

 

Citation: Keenan, T. F. and Niinemets, Ü. (2016). Global leaf trait estimates biased due to plasticity in the shade. Nature plants, 3, 16201, DOI: 10.1038/nplants.2016.201 (link to full text)

 

Abstract:

The study of leaf functional trait relationships, the so-called leaf economics spectrum, is based on the assumption of high-light conditions (as experienced by sunlit leaves). Owing to the exponential decrease of light availability through canopies, however, the vast majority of the world’s vegetation exists in at least partial shade. Plant functional traits vary in direct dependence of light availability, with different traits varying to different degrees, sometimes in conflict with expectations from the economic spectrum. This means that the derived trait relationships of the global leaf economic spectrum are probably dependent on the extent to which observed data in existing large-scale plant databases represent high-light conditions. Here, using an extensive worldwide database of within-canopy gradients of key physiological, structural and chemical traits, along with three different global trait databases, we show that: (1) accounting for light-driven trait plasticity can reveal novel trait relationships, particularly for highly plastic traits (for example, the relationship between net assimilation rate per area (Aa) and leaf mass per area (LMA)); and (2) a large proportion of leaf traits in current global plant databases reported as measured in full sun were probably measured in the shade. The results show that even though the majority of leaves exist in the shade, along with a large proportion of observations, our current understanding is too focused on conditions in the sun.

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