ORCID Profile
0000-0002-5001-0149
Current Organisations
Naturalis Biodiversity Center
,
Leiden University
,
Icahn School of Medicine at Mount Sinai
,
Mount Sinai Hospital
,
New York Medical College
,
NYU Winthrop Hospital
,
Universiteit Leiden Instituut Biologie Leiden
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Publications
Climatic and soil factors explain the two-dimensional spectrum of global plant trait variation
Publisher: Springer Science and Business Media LLC
Date: 23-12-2021
DOI: 10.1038/S41559-021-01616-8
Abstract: Plant functional traits can predict community assembly and ecosystem functioning and are thus widely used in global models of vegetation dynamics and land–climate feedbacks. Still, we lack a global understanding of how land and climate affect plant traits. A previous global analysis of six traits observed two main axes of variation: (1) size variation at the organ and plant level and (2) leaf economics balancing leaf persistence against plant growth potential. The orthogonality of these two axes suggests they are differently influenced by environmental drivers. We find that these axes persist in a global dataset of 17 traits across more than 20,000 species. We find a dominant joint effect of climate and soil on trait variation. Additional independent climate effects are also observed across most traits, whereas independent soil effects are almost exclusively observed for economics traits. Variation in size traits correlates well with a latitudinal gradient related to water or energy limitation. In contrast, variation in economics traits is better explained by interactions of climate with soil fertility. These findings have the potential to improve our understanding of bio ersity patterns and our predictions of climate change impacts on biogeochemical cycles.
Complementing model species with model clades
Publisher: Oxford University Press (OUP)
Date: 12-10-2023
Global convergence in the vulnerability of forests to drought
Publisher: Springer Science and Business Media LLC
Date: 11-2012
DOI: 10.1038/NATURE11688
Abstract: Shifts in rainfall patterns and increasing temperatures associated with climate change are likely to cause widespread forest decline in regions where droughts are predicted to increase in duration and severity. One primary cause of productivity loss and plant mortality during drought is hydraulic failure. Drought stress creates trapped gas emboli in the water transport system, which reduces the ability of plants to supply water to leaves for photosynthetic gas exchange and can ultimately result in desiccation and mortality. At present we lack a clear picture of how thresholds to hydraulic failure vary across a broad range of species and environments, despite many in idual experiments. Here we draw together published and unpublished data on the vulnerability of the transport system to drought-induced embolism for a large number of woody species, with a view to examining the likely consequences of climate change for forest biomes. We show that 70% of 226 forest species from 81 sites worldwide operate with narrow (<1 megapascal) hydraulic safety margins against injurious levels of drought stress and therefore potentially face long-term reductions in productivity and survival if temperature and aridity increase as predicted for many regions across the globe. Safety margins are largely independent of mean annual precipitation, showing that there is global convergence in the vulnerability of forests to drought, with all forest biomes equally vulnerable to hydraulic failure regardless of their current rainfall environment. These findings provide insight into why drought-induced forest decline is occurring not only in arid regions but also in wet forests not normally considered at drought risk.
Traits and trade-offs in whole-tree hydraulic architecture along the vertical axis of Eucalyptus grandis
Publisher: Oxford University Press (OUP)
Date: 2018
DOI: 10.1093/AOB/MCX137
Comparative anatomy vs mechanistic understanding: how to interpret the diameter-vulnerability link
Publisher: Brill
Date: 20-10-2023
Pit membranes in tracheary elements of Rosaceae and related families: new records of tori and pseudotori
Publisher: Wiley
Date: 04-2007
DOI: 10.3732/AJB.94.4.503
Abstract: The micromorphology of pits in tracheary elements was examined in 35 species representing 29 genera of Rosaceae and related families to evaluate the assumption that angiosperm pits are largely invariant. In most Rosaceae, pit membranes between fibers and tracheids frequently appear to have amorphous thickenings with an irregular distribution. Although these structures are torus-like under the light microscope, observations by electron microscopy illustrate that they represent "pseudotori" or plasmodesmata-associated thickenings. These thickenings frequently extend from the periphery of the pit membrane and form a cap-like, hollow structure. Pseudotori are occasionally found in few Elaeagnaceae and Rhamnaceae and appear to be related to species with fiber-tracheids and/or tracheids. True tori are strongly associated with round to oval pit apertures and are consistently present in narrow tracheary elements of Cercocarpus (Rosaceae), Planera (Ulmaceae), and ring-porous species of Ulmus and Zelkova (Ulmaceae). Vestured pits with homogenous pit membranes are reported for Hemiptelea (Ulmaceae). The homoplastic nature of pit membrane characteristics may be related to functional adaptations in terms of safety and efficiency of water transport or may reflect different developmental processes of xylem elements. These observations illustrate that there is more variation in angiosperm pits than previously thought.
Testing hypotheses that link wood anatomy to cavitation resistance and hydraulic conductivity in the genus Acer
Publisher: Wiley
Date: 04-11-2018
DOI: 10.1111/J.1469-8137.2010.03518.X
Abstract: Tansley medal winner p 509
Intervascular pit membranes with a torus in the wood of Ulmus (Ulmaceae) and related genera
Publisher: Wiley
Date: 13-05-2004
Functional xylem characteristics associated with drought-induced embolism in angiosperms.
Publisher: Wiley
Date: 19-09-2022
DOI: 10.1111/NPH.18447
Abstract: Hydraulic failure resulting from drought-induced embolism in the xylem of plants is a key determinant of reduced productivity and mortality. Methods to assess this vulnerability are difficult to achieve at scale, leading to alternative metrics and correlations with more easily measured traits. These efforts have led to the longstanding and pervasive assumed mechanistic link between vessel diameter and vulnerability in angiosperms. However, there are at least two problems with this assumption that requires critical re-evaluation: (1) our current understanding of drought-induced embolism does not provide a mechanistic explanation why increased vessel width should lead to greater vulnerability, and (2) the most recent advancements in nanoscale embolism processes suggest that vessel diameter is not a direct driver. Here, we review data from physiological and comparative wood anatomy studies, highlighting the potential anatomical and physicochemical drivers of embolism formation and spread. We then put forward key knowledge gaps, emphasising what is known, unknown and speculation. A meaningful evaluation of the diameter-vulnerability link will require a better mechanistic understanding of the biophysical processes at the nanoscale level that determine embolism formation and spread, which will in turn lead to more accurate predictions of how water transport in plants is affected by drought.
TRY plant trait database – enhanced coverage and open access
Publisher: Wiley
Date: 31-12-2019
DOI: 10.1111/GCB.14904
Abstract: Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to bio ersity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on in idual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.
On research priorities to advance understanding of the safety–efficiency tradeoff in xylem
Publisher: Wiley
Date: 27-06-2016
DOI: 10.1111/NPH.14043
Combination of Gene Expression Signature and Model for End-Stage Liver Disease Score Predicts Survival of Patients With Severe Alcoholic Hepatitis
Publisher: Elsevier BV
Date: 03-2018
Global Phylogeny of the Brassicaceae Provides Important Insights into Gene Discordance
Publisher: Cold Spring Harbor Laboratory
Date: 09-2022
DOI: 10.1101/2022.09.01.506188
Abstract: The mustard family (Brassicaceae) is a scientifically and economically important family, containing the model plant Arabidopsis thaliana and numerous crop species that feed billions worldwide. Despite its relevance, most published family phylogenies are incompletely s led, generally contain massive polytomies, and/or show incongruent topologies between datasets. Here, we present the most complete Brassicaceae genus-level family phylogenies to date (Brassicaceae Tree of Life, or BrassiToL) based on nuclear ( ,000 genes, almost all 349 genera and 53 tribes) and plastome (60 genes, 79% of the genera, all tribes) data. We found cytonuclear discordance between nuclear and plastome-derived phylogenies, which is likely a result of r ant hybridisation among closely and more distantly related species, and highlight rogue taxa. To evaluate the impact of this r ant hybridisation on the nuclear phylogeny reconstruction, we performed four different s ling routines that increasingly removed variable data and likely paralogs. Our resulting cleaned subset of 297 nuclear genes revealed high support for the tribes, while support for the main lineages remained relatively low. Calibration based on the 20 most clock-like nuclear genes suggests a late Eocene to late Oligocene ‘icehouse origin’ of the family. Finally, we propose five new or re-established tribes, including the recognition of Arabidopsideae, a monotypic tribe to accommodate Arabidopsis . With a worldwide community of thousands of researchers working on this family, our new, densely s led family phylogeny will be an indispensable tool to further highlight Brassicaceae as an excellent model family for studies on bio ersity and plant biology.
Rooting depth and xylem vulnerability are independent woody plant traits jointly selected by aridity, seasonality, and water table depth
Publisher: Wiley
Date: 24-09-2023
DOI: 10.1111/NPH.19276
Weak tradeoff between xylem safety and xylem‐specific hydraulic efficiency across the world's woody plant species
Publisher: Wiley
Date: 17-09-2015
DOI: 10.1111/NPH.13646
Abstract: The evolution of lignified xylem allowed for the efficient transport of water under tension, but also exposed the vascular network to the risk of gas emboli and the spread of gas between xylem conduits, thus impeding sap transport to the leaves. A well‐known hypothesis proposes that the safety of xylem (its ability to resist embolism formation and spread) should trade off against xylem efficiency (its capacity to transport water). We tested this safety–efficiency hypothesis in branch xylem across 335 angiosperm and 89 gymnosperm species. Safety was considered at three levels: the xylem water potentials where 12%, 50% and 88% of maximal conductivity are lost. Although correlations between safety and efficiency were weak ( r 2 0.086), no species had high efficiency and high safety, supporting the idea for a safety–efficiency tradeoff. However, many species had low efficiency and low safety. Species with low efficiency and low safety were weakly associated ( r 2 0.02 in most cases) with higher wood density, lower leaf‐ to sapwood‐area and shorter stature. There appears to be no persuasive explanation for the considerable number of species with both low efficiency and low safety. These species represent a real challenge for understanding the evolution of xylem.
Herbaceous angiosperms are not more vulnerable to drought-induced embolism than angiosperm trees
Publisher: Oxford University Press (OUP)
Date: 07-06-2016
DOI: 10.1104/PP.16.00829
Abstract: The water transport pipeline in herbs is assumed to be more vulnerable to drought than in trees due to the formation of frequent embolisms (gas bubbles), which could be removed by the occurrence of root pressure, especially in grasses. Here, we studied hydraulic failure in herbaceous angiosperms by measuring the pressure inducing 50% loss of hydraulic conductance (P
Exploring the Hydraulic Failure Hypothesis of Esca Leaf Symptom Formation
Publisher: Oxford University Press (OUP)
Date: 27-08-2019
DOI: 10.1104/PP.19.00591
Related Organisations
Icahn School Of Medicine At Mount Sinai
Location: United States of America
Related Funding Activities
No related grants have been discovered for Frederic Lens.