Find research datasets worth reusing

Data from: Latent developmental and evolutionary shapes embedded within the grapevine leaf

<ul> <li>Across plants, leaves exhibit profound diversity in shape. As a single leaf expands, its shape is in constant flux. Plants may also produce leaves with different shapes at successive nodes. In addition, leaf shape varies among individuals, populations and species as a result of evolutionary processes and environmental influences.</li> <li>Because leaf shape can vary in many different ways, theoretically, the effects of distinct developmental and evolutionary processes are separable, even within the shape of a single leaf. Here, we measured the shapes of > 3200 leaves representing > 270 vines from wild relatives of domesticated grape (Vitis spp.) to determine whether leaf shapes attributable to genetics and development are separable from each other.</li> <li>We isolated latent shapes (multivariate signatures that vary independently from each other) embedded within the overall shape of leaves. These latent shapes can predict developmental stages independent from species identity and vice versa. Shapes predictive of development were then used to stage leaves from 1200 varieties of domesticated grape (Vitis vinifera ), revealing that changes in timing underlie leaf shape diversity.</li> <li>Our results indicate that distinct latent shapes combine to produce a composite morphology in leaves, and that developmental and evolutionary contributions to shape vary independently from each other.</li> </ul>

Root trait responses to drought are more heterogeneous than leaf trait responses

Drought can strongly modify plant diversity and ecosystem processes. As droughts are expected to intensify in the future, it is important to better understand plant responses to this global driver. Root traits are an overlooked but powerful predictor of plant responses to drought because they are in direct contact with the soil environment and are responsible for taking up nutrients and water. Here, we determine which root traits are sensitive to drought and the magnitude of that response. We also tested whether root trait relationships with shoot biomass are affected by drought and to what extent all these responses depend on plant species identity. To do so, we conducted a glasshouse experiment with 24 plant species grown in pots (10 replicates per species), which included grasses, forbs and legumes. All replicates were well watered during the first month and then half of them were kept under drought (30 % water holding capacity (WHC)), with the other half serving as control (70 % WHC). After two months of treatment, leaf and root traits were measured. Leaf traits had a strong and more uniform response to drought compared to root traits. Root trait responses were variable and differed among plant species. Overall, grasses and several forbs had increased root diameter with drought while forbs had decreased specific root surface area (SRSA) and specific root length (SRL). Increase of root diameter and reduction of root elongation or sacrificing fine roots are different strategies that may promote nutrient and water acquisition, depending on plant species identity. Our results identify changes in root morphological traits as mechanisms to likely tolerate drought and highlight that, although such drought responses are species-specific, they are phylogenetically clustered.

Data from: Addition of nitrogen to canopy versus understory has different effects on leaf traits of understory plants in a subtropical evergreen broad–leaved forest

Atmospheric nitrogen (N) deposition has substantial effects on forest ecosystems. The effects of N deposition on understory plants have been simulated by spraying N on the forest floor. Such understory addition of N (UAN) might simulate atmospheric N deposition in a biased manner, because it bypasses the canopy. We compared the effects of UAN and canopy addition of N (CAN) at 0, 25, and 50 kg N ha–1 year–1 on specific leaf area (SLA), leaf construction costs (CC), concentrations of leaf carbon ([C]), nitrogen ([N]), phosphorus ([P]), minerals ([Mineral]), nitrate ([NO3-]), lignin ([Lignin]), lipids ([Lipid]), organic acids ([OA]), soluble phenolics ([SP]), total non-structural carbohydrates ([TNC]), and total structural carbohydrates ([TSC]) in six dominant understory species in a subtropical evergreen forest after five years of N treatments. We found that leaf CC, [C], [Lignin], [OA], [TNC] and [TSC] were significantly affected by N-addition approach and rate, but leaf [P] and [Lipid] were affected by N-addition approach and N-addition rate, respectively; leaf CC, [C], [P], [OA], and [TNC] were significantly lower under UAN than under CAN, but leaf [TSC] and [Lignin] were significantly higher and lower, respectively, under UAN than under CAN at 50 kg N ha–1 year–1; the decline of leaf [C] and [Lignin] contributed to the significantly lower leaf CC under UAN than under CAN. Synthesis. We show that canopy and understory N addition exerted significantly different effects on leaf traits of understory plants. The results indicate that understory plants in subtropical forest respond differently to understory addition of N from those to atmospheric deposition of N. Further studies are warranted to evaluate the unbiased ecological processes and functions of forest ecosystem responding to atmospheric N deposition via both canopy and understory N addition experiments over a longer term.

Environmental determinants of leaf-litter ant community composition along an elevational gradient

Ant communities are extremely diverse and provide a wide variety of ecological functions in tropical forests. Here we investigated the abiotic factors driving ant composition turnover across an elevational gradient at Mont Itoupé, French Guiana. Mont Itoupé is an isolated mountain whose top is covered by cloud forests, a biogeographical rarity that is likely to be threatened according to climate change scenarios in the region. We examined the influence of six soil, climatic and LiDAR-derived vegetation structure variables on leaf-litter ant assembly (267 species) across nine 0.12-ha plots disposed at three elevations (ca. 400, 600 and 800m asl). We tested (a) whether species co-occurring within a same plot or a same elevation were more similar in terms of taxonomic, functional and phylogenetic composition, than species from different plots/elevations, and (b) which environmental variables significantly explained compositional turnover among plots. We found that the distribution of species and traits of ant communities along the elevational gradient was significantly explained by a turnover of environmental conditions, particularly in soil phosphorus and sand content, canopy height and mean annual relative humidity of soil. Our results shed light on the role exerted by environmental filtering in shaping ant community assembly in tropical forests. Identifying the environmental determinants of ant species distribution along tropical elevational gradients could help predicting the future impacts of global warming on biodiversity organization in vulnerable environments such as cloud forests.

Photosynthetic heat tolerances and extreme leaf temperatures

Photosynthetic heat tolerances (PHTs) have several potential applications including predicting which species will be most vulnerable to climate change. Given that plants exhibit unique thermoregulatory traits that influence leaf temperatures, and that leaf temperatures can be decoupled from ambient air temperatures, we hypothesized that PHTs should be correlated to extreme leaf temperature as opposed to air temperatures. We measured thermoregulatory traits, maximum leaf temperatures (TMO), and two metrics of PHTs (Tcrit and T50) for 19 plant species growing in Fairchild Tropical Botanic Garden (Coral Gables, FL, USA). Thermoregulatory traits measured at the Garden were used to parameterize a leaf energy balance model to predict maximum in situ leaf temperatures (TMIS) across the geographic distributions of 13 species. TMO and TMIS were positively correlated with T50 but were not correlated with Tcrit. The breath of species' thermal safety margins (the difference between T50 and leaf temperatures) was negatively correlated with T50. Our results provide observational and theoretical support for the hypothesis that PHTs may be adaptations to extreme leaf temperature, but refute the assumption that species with higher PHTs are less susceptible to thermal damage. We introduce a novel method for studying plant ecophysiology by incorporating biophysical and species distribution models.

opencc-by-4.0Aug 2014View details →

Figure 3 in Distinct parasitoid communities associated with host races of the leaf-mining moth Acrocercops transecta on distantly related host plants (Juglandaceae and Ericaceae)

Figure 3. Lateral view of female Aneurobracon philippinensis.

opencc-by-4.0Aug 2014View details →

Figure 2 in Distinct parasitoid communities associated with host races of the leaf-mining moth Acrocercops transecta on distantly related host plants (Juglandaceae and Ericaceae)

Figure 2. Map of Japan showing the sampling localities of Acrocercops transecta mines.

opencc-zeroSep 2020View details →

Data from: Early spring warming may hasten leaf emergence in Erythronium americanum

Premise of the study: Climate change is making spring arrive earlier than in the past, causing some species to alter the timing of their spring activities. This study addressed whether Erythronium americanum Ker Gawl. (trout lily), a common spring ephemeral, can hasten its spring emergence if exposed to early spring warming. Methods: I collected corms of E. americanum in the fall, overwintered them in soil, and exposed them to warming in either mid (early treatment) or late (late treatment) February. The timing of leaf emergence was monitored and compared between treatments. Key results: Leaves exposed to early warming emerged earlier than those in the late treatment. Bud break happened closer to date of exposure to warming in the late treatment than in the early treatment. Conclusions: Spring ephemerals may be able to produce leaves early in response to early spring warming induced by climate change. Risk of late frost and eventual shading by the canopy may limit the duration of a potentially extended growing season. Please be aware that if you ask to have your user record removed, we will retain your name in the records concerning manuscripts for which you were an author, reviewer, or editor. In compliance with data protection regulations, you may request that we remove your personal registration details at any time. (Use the following URL: https://www.editorialmanager.com/ajb/login.asp?a=r). Please contact the publication office if you have any questions.

opencc-by-4.0Aug 2020View details →

Leaf Vein Network CNN Images

This download site contains the CNN vein network predictions and set of Matlab programs  that were used for the analyses in Xu et al., (2020) and Blonder et al., (2020). These require Matlab 2020a or later. They may work on earlier versions of MatLab, but this has not been tested and cannot be guaranteed. The files are as follows: <ol> <li>Zip files (e.g. BEL_downsampled_images.zip) containing a complete set of images of leaf vein predictions from a fully trained convolutional neural network (CNN), along with the ground truth data. Each folder in the unzipped file contains a sample represented by a CODE with format X-TY-BZ. X represents the name of a plot in the Global Ecosystems Monitoring network database (e.g. 'BEL'). Tree (T) Y indicates the number of a tree within a plot (e.g. '101') and Z represents the light stratum of the canopy where the leaf was collected (either 'S' for 'sunlit' or 'SH' for 'shaded').</li> <li>A set of Matlab programs (Matlab files.zip) to compare the CNN predictions against other vein extraction approaches.</li> <li>A Matlab Readme file with instructions on how to run the analyses.</li> </ol> References Software GUI: Xu, H., Blonder, B., Jodra, M., Malhi, Y. and Fricker, M.D. (2020) Automated and accurate segmentation of leaf venation networks via deep learning. New Phytol. (In press). Analysis of trait data: Blonder, B., S. Both, M. Jodra, H. Xu, M. Fricker, I. S. Matos, N. Majalap, D. F. R. P. Burslem, Y. Teh and Y. Malhi (2020) Linking functional traits to multiscale statistics of leaf venation networks. New Phytol. (In press). Original image data set and ground truths Blonder, B., Both, S., Jodra, M., Majalap, N., Burslem, D., Teh, Y. A., and Malhi, Y. (2019) Leaf venation networks of Bornean trees: images and hand‐traced segmentations. Ecology 100: e02844.<a href="https://doi.org/10.1002/ecy.2844">10.1002/ecy.2844</a>. Available from: <a href="https://ora.ox.ac.uk/objects/uuid:de65fc07-4b8f-4277-a6c4-82836afbdeb3">https://ora.ox.ac.uk/objects/uuid:de65fc07-4b8f-4277-a6c4-82836afbdeb3</a>

opencc-by-4.0Sep 2020View details →

Mass spectra of leaf extracts from maize

Mass fingerprints of leaf extracts from B73 and Mo17 maize lines. Eleven biological replicates for each genotype were evaluated.

opencc-zeroSep 2020View details →

Data from: A tale of scale: plot but not neighbourhood tree diversity increases leaf litter ant diversity

1. Diversity of producers (e.g. plants) usually increases the diversity of associated organisms, but the scale (i.e. the spatial area of plant diversity considered) at which plant diversity acts on other taxa has rarely been studied. Most evidence for cross-taxon diversity relations come from aboveground consumers that directly interact with plants. 2. Experimental tests of plant diversity effects on elusive organisms inhabiting the leaf litter layer, which are important for nutrient cycling and decomposition, are rare. 3. Using a large tree diversity experiment, we tested whether tree diversity at the larger plot (i.e. community) or the smaller neighbourhood scale relates to the abundance, species richness, functional, and phylogenetic diversity of leaf litter ants, which are dominant organisms in brown food webs. 4. Contrary to our expectations of scale-independent positive tree diversity effects, ant diversity increased only with plot but not neighbourhood tree diversity. While the exact causal mechanisms are unclear, nest relocation or small-scale competition among ants may explain the stronger tree diversity effects at the plot scale. 5. Our results indicate that even for small and less mobile organisms in the leaf litter, effects of tree diversity are stronger at relatively larger scales. The finding emphasize the importance of diverse forest stands, in which mixing of tree species is not restricted to small patches, for supporting arthropod diversity in the leaf litter.

opencc-by-4.0Oct 2020View details →

Thesis DRIS leaf nutrient analysis results

The data file contains results from leaf nutrient analysis that have been analyzed with the Florida citrus DRIS program, created by Arnold Schumann (UF IFAS Citrus Research and Education Center, Soil and Precision Agricultura Lab). This data was used to train an AI model to recognize nutrient deficiencies of citrus.

opencc-zeroOct 2020View details →

Data from: Drivers of bromeliad leaf and floral bract variation across a latitudinal gradient in the Atlantic Forest

Aim: Understanding the complex interaction and relative contributions of factors involved in species and trait diversification is crucial to gain insights into the evolution of Neotropical biodiversity. Here, we investigated the drivers of morphological variation in bromeliads along a latitudinal gradient in a biodiversity hotspot. Location: Atlantic Forest, Brazil. Taxon: A species complex in the genus Vriesea (Bromeliaceae). Methods: We measured shape and size variation for 208 floral bracts and 176 leaves in individuals from 14 localities using geometric morphometrics. We compiled data for two chloroplast regions (matK and trnL-F) from 89 individuals to assess genetic diversity, population structure and phylogenetic relationships. We tested the influence of climate, altitude and genetic distance on morphological traits using linear statistical models. Results: Temperature seasonality is a main driver of floral bract shape. Together with precipitation, it also explains changes in leaf size across the latitudinal gradient. Shifts in morphological traits are correlated with genetic structure and partly support the recent taxonomic delimitation proposed for the species complex. The species started to diversify in the Pliocene ca. 5 Mya. We detected a phylogeographic break in species distribution into northern and southern clades between the Bocaina region and the southern portion of the Atlantic Forest. Main conclusions: We identify how geography and environmental changes through time shape floral bracts and leaves in similar ways. At highly seasonal sites with lower annual precipitation (in the southern subtropical portion of the Atlantic Forest), leaves are larger and floral bracts are wide-elliptic, making them better suited for increased water accumulation. In contrast, at less seasonal sites (in the tropical north, where rainfall is more abundant and temperatures are higher), leaves are narrower and floral bracts are lanceolate-shaped, facilitating water drainage. The biogeographical break we identified suggests a role of tectonic activity and climatic oscillations in promoting species divergence and diversification.

opencc-zeroNov 2020View details →

Data from: Climate warming prolongs the time interval between leaf-out and flowering in temperate trees: effects of chilling, forcing and photoperiod

1. Leaf-out and flowering are two key phenological events of plants, denoting the respective onsets of visible vegetative growth and reproduction during the year. For each species, the schedule of vegetative growth and reproduction is crucial to the maximization of its fitness. Warming-induced advances of leaf-out and flowering have been reported frequently, however, it is unclear whether the responses of the two events are equal for any given species. 2. Using long-term phenological records in Europe, we examined simultaneously the responses of both leaf-out and flowering of four common temperate tree species to climate warming and further examined the effects of winter chilling, spring forcing and photoperiod on the responses of the two events. 3. We found that regardless whether flowering or leaf-out occurred first, the first event advanced more than the second during 1950 – 2013, resulting in a prolonged time interval between the two events. The temporal changes were also supported by a similar geographical trend that the time interval between the two events increased from cold to warm sites. Due to the warming-induced reduction in chilling, the spring forcing accumulated until the second event was increased more than the forcing accumulated until the first event, and that reduced the temperature sensitivity of the second event. In addition to the effect of chilling, the shorter photoperiod, associated with the advanced spring phenology, was also likely to substantially increase the spring forcing accumulated until the second event, which thus slowed down its advance, compared to the advance of the first event. The relative contributions of chilling and photoperiod to the increased forcing varied between species and events, with chilling mostly outweighing photoperiod. 4. Synthesis. This study provides the large-scale empirical evidence of prolonged time interval between leaf-out and flowering with climate warming. The unequal advances of the two events may alter the partition of resources between vegetative growth and reproduction and cause different changes of spring frost damage to vegetative and reproductive tissues, which may alter species fitness and further affect ecosystem structure and function.

opencc-zeroNov 2020View details →

Plant size and leaf traits for epiphyte species found in flooded gallery forests and non-flooded gallery forests in Central Brazil

Despite their unique adaptations to thrive in canopy environments without access to soil resources, epiphytes are underrepresented in studies of functional traits and of functional composition of tropical plant communities. We investigated functional traits of spermatophytic (seed-bearing) C3 and CAM epihyte communities in flooded and non-flooded gallery forests in Central Brazil. The two forest types differ in floristic, structure, microclimate and edaphic conditions. We studied plant size, leaf thickness, leaf dry matter content, leaf area, specific leaf area, leaf C, N, P, K, Mg, Ca and C and N stable isotope ratios. Because photosynthetic pathway (C3 or CAM) is an important aspect of ecologial differentiation of spermatophytic epiphytes, we expected that functional trait syndromes in a multivariate space would be more associated with photosynthetic pathway than forest type and changes in abundance of C3 and CAM epiphytes would drive functional trait composition at the community level. C3 and CAM epiphytes segregated in the multivariate trait space, however more complex functional typologies were also evident. Despite lower light levels, CAM epiphytes were more abundant in the flooded gallery forest. There, they accounted for 80% of all individuals, whereas C3 epiphytes dominated in the non-flooded forest. These large differences in the proportion of C3 and CAM epiphytes strongly affected functional trait values at the community level, despite very little intraspecfic variation in trait values between forest types for species that occurred in both forests.

opencc-zeroDec 2020View details →

Data from: Leaf litter decomposition in tropical freshwater swamp forests is slower in swamp than non-swamp conditions

Decomposition is a key ecosystem function, and the rate of decomposition in forests affects their carbon storage potentials. Processes and factors determining leaf litter decomposition rates in dry-land and temperate forests are well understood, but these are generally poorly studied in tropical wetland forests, especially freshwater swamp forests (FSF). The home-field advantage (HFA) hypothesis predicts that soil microbes specialize in decomposing leaf litter produced by the tree species in their immediate vicinity. However, empirical support for the HFA is equivocal, and the HFA has never been tested in the highly heterogeneous and biodiverse ecosystems of tropical FSFs. We collected leaf litter from swamp and non-swamp tree species in a tropical FSF in Singapore and monitored the decomposition rates of these in swamp and non-swamp plots for a period of eight months. Leaf litter decomposed 3.7 times more slowly in swamp plots. Leaf litter from swamp tree species were significantly poorer in quality (higher C:N ratio) than those of non-swamp FSF tree species, but this had only a weak effect on decomposition rates. There was also only weak evidence for the HFA and only in non-swamp conditions. Our results show that while the leaf litter of tropical FSF swamp and non-swamp tree species differ significantly in chemical traits, litter decomposition rate is ultimately determined by local abiotic conditions, such as hydrology. Additionally, the high FSF tree diversity may prevent decomposer communities from specializing on any group of leaf litter types and thus limit the extent of HFA observed in such heterogeneous forests.

opencc-zeroDec 2020View details →

The timing of leaf senescence relates to flowering phenology and functional traits in 17 herbaceous species along elevational gradients

1. Leaf senescence is a major event in a plant's life history as autumn marks the end of the growing season. The optimal timing of leaf senescence is crucial to both, minimize risks of low temperature events and maximize carbon gain during the growing season. As abiotic conditions are currently changing at unprecedented rates, it is important to study how leaf senescence of different species is responding to these changes in order to forecast future growing season length and carbon sequestration potentials. In contrast to flowering phenology, data on autumn events is scarce and even more so for herbaceous than for woody plants, thus more information on this phenological stage is urgently needed. 2. We studied leaf senescence of 632 populations from 17 herbaceous species located along elevational gradients. We focussed on the beginning (5% of the population senesce, LS5) and peak (50% senesce, LS50) of leaf senescence. To see whether we can predict species-specific changes, we studied the link between LS5 and LS50 and flowering phenology as well as leaf functional traits related to plant performance. We looked at first and last flowering day and flowering duration as well as the traits specific leaf area, leaf dry matter content, area based leaf nitrogen and carbon content, carbon isotope discrimination (Δ13C), and the stomatal pore area index. 3. We found species-specific slopes of the beginning of leaf senescence along the elevational gradient. The peak of leaf senescence was uniformly delayed with increasing elevation across all species. Flowering phenology as well as leaf functional traits had a close relationship with leaf senescence and thus can be used to forecast species-specific responses to changes in abiotic conditions. High SLA and high leaf nitrogen were related to earlier senescence while high LDMC, high Δ13C and high SPI to later senescence. 4. Synthesis: The link between senescence, flowering phenology and plant functional traits will help to fine-tune predictions of future growing season length and ecosystem function. To date, most analyses are based on spring phenology and traits, for which data is more abundant than data on autumn senescence.

opencc-zeroApr 2020View details →

C4 photosynthesis and the economic spectra of leaf and root traits independently influence growth rates in grasses

Photosynthetic pathway is an important cause of growth rate variation between species, such that the enhanced carbon uptake of C4 species leads to faster growth than their C3 counterparts. Leaf traits that promote rapid resource acquisition may further enhance the growth capacity of C4 species. However, how root economic traits interact with leaf traits, and the different growth strategies adopted by plants with C3 and C4 photosynthetic pathways is unclear. Plant economic traits could interact with, or act independently of, photosynthetic pathway in influencing growth rate, or C3 and C4 species could segregate out along a common growth rate-trait relationship. We measured leaf and root traits on 100+ grass species grown from seeds in a controlled, common environment to compare with relative growth rates (RGR) during the initial phase of rapid growth, controlling for phylogeny and allometric effects. Photosynthetic pathway acts independently to leaf and root functional traits in causing fast growth. Using C4 photosynthesis, plants can achieve faster growth than their C3 counterparts (by an average 0.04 g g-1 day-1) for a given suite of functional trait values, with lower investments of leaf and root nitrogen. Leaf and root traits had an additive effect on RGR, with plants achieving fast growth by possessing resource-acquisitive leaf traits (high specific leaf area and low leaf dry matter content) or root traits (high specific root length and area, and low root diameter), but having both leads to an even faster growth rate (by up to 0.06 g g-1 day-1). C4 photosynthesis can provide a greater relative increase in RGR for plants with a 'slow' ecological strategy than in those with fast growth. However, aboveground and belowground strategies are not coordinated, so that species can have any combination of 'slow' or 'fast' leaf and root traits. Synthesis: C4 photosynthesis increases growth rate for a given combination of economic traits, and significantly alters plant nitrogen economy in the leaves and roots. However, leaf and root economic traits act independently to further enhance growth. The fast growth of C4 grasses promotes a competitive advantage under hot, sunny conditions.

opencc-zeroFeb 2021View details →

Leaf margins in a deciduous lineage from the Greater Cape Floristic Region track climate in unexpected directions

Premise of the study: The functional significance of leaf margins has long been debated. In this study we explore influences of climate, leaf lobing, woodiness, and shared evolutionary history on two leaf margin traits within the genus Pelargonium. Methods: Leaves from 454 populations of Pelargonium (161 species) were collected in the Greater Cape Floristic Region and scored for tooth presence/absence and degree of lobing. Tooth density (number of teeth per interior perimeter distance) was measured for a subset of these. We compared five hypotheses to explain tooth presence and density using mixed effect models. Key results: Tooth presence/absence was best predicted by the interaction of leaf lobing and mean annual temperature (MAT), but often in patterns opposite to the previous literature: species were more likely to be toothed with warmer temperatures. This was particularly the case for unlobed and highly lobed leaves. In contrast, tooth density was best predicted by the interaction of MAT and the season of most rain; density declines with temperature as consistent with expectations, but only in winter- rain dominated areas. Woody and non-woody species within Pelargonium both have similar associations between tooth presence/absence and MAT, contrary to the expectation that patterns within non-woody species would be insignificant. Conclusions: We conclude Pelargonium leaf margins show predictable responses to climate, but these responses are complex and can contradict those found for global patterns across plant communities.