Person: Delgado Sáez, Juan Antonio
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First Name
Juan Antonio
Last Name
Delgado Sáez
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Biológicas
Department
Biodiversidad, Ecología y Evolución
Area
Ecología
Identifiers
4 results
Search Results
Now showing 1 - 4 of 4
Item Data on samara morphology and wind dispersal in the invasive tree Ailanthus altissima(2019) Planchuelo, Greg; Catalán, Pablo; Delgado Sáez, Juan Antonio; Murciano Cespedosa, AntonioThe data presented in this paper is supporting the research article “Estimating wind dispersal potential in Ailanthus altissima: The need to consider the three-dimensional structure of samaras” [1]. We analyzed the estimation of samara's wind dispersal potential through a group of morphological variables that succeed in describing the three-dimensional nature of samaras. We present here a dataset containing 8 morphological variables of 200 samaras belonging to 5 different individuals of the invasive tree Ailanthus altissima (Mill.) Swingle. Additionally, we present the average descent velocity of each of the samaras, which was recorded by releasing 5 times each samara under controlled and reproducible conditions. The data set is structured in a single spreadsheet where we also included the samara and the individual identity code of the tree.Item The expression of light-related leaf functional traits depends on the location of individual leaves within the crown of isolated Olea europaea trees(Annals of Botany, 2016) Escribano Rocafort, Adrián Gaspar; Ventre-Lespiaucq, Agustina B.; Granado Yela, Carlos; Rubio de Casas, Rafael; Delgado Sáez, Juan Antonio; Balaguer, LuisBackground: The spatial arrangement and expression of foliar syndromes within tree crowns can reflect the coupling between crown form and function in a given environment. Isolated trees subjected to high irradiance and concomitant stress may adjust leaf phenotypes to cope with environmental gradients that are heterogeneous in space and time within the tree crown. The distinct expression of leaf phenotypes among crown positions could lead to complementary patterns in light interception at the crown scale. Methods: We quantified eight light-related leaf traits across 12 crown positions of ten isolated Olea europaea trees in the field. Specifically, we investigated whether the phenotypic expression of foliar traits differed among crown sectors and layers and five periods of the day from sunrise to sunset. We investigated the consequences in terms of the exposed area of the leaves at the tree scale during a single day. Key Results: All traits differed among crown positions except the length-to-width ratio of the leaves. We found a strong complementarity in the patterns of the potential exposed area of the leaves among day periods as a result of a non-random distribution of leaf angles across the crown. Leaf exposure at the outer layer was below 60 % of the displayed surface, reaching maximum interception during morning periods. Daily interception increased towards the inner layer, achieving consecutive maximization from east to west positions within the crown, matching the sun’s trajectory. Conclusions: The expression of leaf traits within isolated trees of O. europaea varies continuously through the crown in a gradient of leaf morphotypes and leaf angles depending on the exposure and location of individual leaves. The distribution of light-related traits within the crown and the complementarity in the potential exposure patterns of the leaves during the day challenges the assumption of low trait variability within individuals.Item Effects of fertilization and neighbour removal on biomass allocation and fruit production in Cistus ladanifer(Plant Biosystems, 2011) Delgado Sáez, Juan Antonio; Serrano Talavera, José Manuel; López, F.; Acosta, F. J.The aim of this article was to assess short-term (11 months) changes in vegetative biomass allocation and in reproductive output in response to increased nutrient availability and to different intra-specific competition scenarios in adult C. ladanifer plants. We performed a factorial field experiment with four treatments: (1) no fertilization and no neighbour removal, (2) fertilization (400 kg ha71 of controlled release NPK fertilizer) and no neighbour removal, (3) no fertilization and neighbour removal (all vegetation growing within a 2 m radius around the target plant were cut) and (4) fertilization and neighbour removal. We found a significant interaction between fertilization and neighbour removal affecting patterns of biomass allocation; plants without neighbours allocated relatively more biomass to leaves and less to branches only in the nonfertilized group, with no evident effect on the fertilized one. Furthermore, the positive effects of neighbour removal on number and biomass of fruits were appreciable regardless of nutrient conditions, which suggest that competition intensity was independent from soil fertility.Item Intraindividual variation in light-related functional traits: magnitude and structure of leaf trait variability across global scales in Olea europaea trees(Trees, 2017) Escribano Rocafort, Adrián Gaspar; Ventre Lespiaucq, Agustina Bernardita; Granado Yela, Carlos; Rubio de Casas, Rafael; Delgado Sáez, Juan Antonio; Escudero Alcántara, Adrián; Balaguer, LuisIntraspecific variation in leaf functional traits can play a crucial role at multiple ecological scales. However, our understanding of leaf functional trait variation (FV) across spatial scales is limited. Moreover, the influence of FV in specific responses to the environment remains poorly assessed. We investigated FV across multiple nested ecological scales in a set of leaf traits related to light interception and photosynthetic performance in eight populations of Olea europaea trees distributed over a wide latitudinal gradient (~60°). Specifically, we measured SLA, leaf shape, leaf’s spatial position (leaf angles) and leaf’s potential exposure to direct sunlight (silhouette area of the leaf blade and silhouette to area ratio of the leaf blade). The variability in leaf traits revealed two main patterns depending on the considered trait. Differences among sites absorbed >50% of the trait variation related to leaf shape and structure. Conversely, traits related to leaf position and exposure to direct light varied mostly within individuals among crown positions. The variation within trees for multiple traits ranged from 4 to 14%. Trees of equatorial populations had wider, thinner and more exposed leaves to direct light than trees of the remaining populations. The FV for multiple leaf traits at the tree scale was spatially structured within the tree crown and was higher for populations at the equator than for populations located in other latitudes. The differences among traits and scales in the magnitude of FV revealed a complex structure that could be linked to local adaptation.