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Pinto-Ledezma, J. N.

Publications and source records attributed to Pinto-Ledezma, J. N..

8 recordsLinked to original sources

Mapping oak wilt disease using phenological observations from space

Protecting the future of forests relies on our ability to observe changes in forest health. Thus, developing tools for sensing diseases in a timely fashion is critical for managing threats at broad scales. Oak wilt --a disease caused by a pathogenic fungus (Bretziella fagacearum)-- is threatening oaks, killing thousands yearly while negatively impacting the ecosystem services they provide. Here we propose a novel workflow for mapping oak wilt by targeting temporal disease progression through symptoms using land surface phenology (LSP) from spaceborne observations. By doing so, we hypothesize that phenological changes in pigments and photosynthetic activity of trees affected by oak wilt can be tracked using LSP metrics derived from the Chlorophyll/Carotenoid Index (CCI). We used dense time-series observations from Sentinel-2 to create Analysis Ready Data across Minnesota and Wisconsin and to derive three LSP metrics: the value of CCI at the start and end of the growing season, and the coefficient of variation of the CCI during the growing season. We integrate high-resolution airborne imagery in multiple locations to select pixels (n = 3,872) from the most common oak tree health conditions: healthy, symptomatic for oak wilt, and dead. These pixels were used to train an iterative Partial Least Square Discriminant (PLSD) model and derive the probability of an oak tree (i.e., pixel) in one of these conditions and the associated uncertainty. We assessed these models spatially and temporally on testing datasets revealing that it is feasible to discriminate among the three health conditions with overall accuracy between 80-82%. Within conditions, our models suggest that spatial variations among three CCI-derived LSP metrics can predict healthily (Area Under the Curve (AUC) = 0.98), symptomatic (AUC = 0.89), and dead (AUC = 0.94) oak trees with low false positive rates. The model performance was robust across different years as well. The predictive maps were used to guide local stakeholders in locating disease hotspots for ground verification and subsequent decision-making for treatment. Our results highlight the capabilities of LSP metrics from dense spaceborne observations to map diseases and their importance for monitoring changes in biodiversity at large scales.

ecology↗

Phylogenetic relatedness of plant species co-occurring with an invasive alien plant species (Anthemis cotula L. ) varies with elevation

Darwins naturalization conundrum, which posits that the alien species either succeed in the introduced region because being phylogenetically related to the native species hence being pre-adapted, or are phylogenetically dissimilar to native species and thus occupy unfilled niches, has received a lot of attention but the results have been contradictory. Instead of the usual phylogenetic comparison between native and introduced species to address this conundrum, we followed a novel approach of studying the phylogenetic relationship of a highly widespread and invasive species, Anthemis cotula L. (focal species) separately with the native species and all its co-occurring species (including native and non-native species) along an elevation gradient. The abundance of A. cotula declined continuously with an increase in elevation and species richness. The phylogenetic relationship between the focal species and all the co-occurring species using abundance-weighted mean pair-wise distance (MPDaw) showed an increase with an increase in elevation and species richness. A similar but slightly weaker relationship was noticed when the non-abundance weighted mean pair-wise distance (MPDpa) was used. Interestingly, the phylogenetic distance between the focal species and the native species based on MPDaw declined with elevation as well as species richness, but such a decline was seen when MPDpa was used. Our study also revealed that soil nutrients influence the abundance of A. cotula and the phylogenetic distance between the focal and other species, thereby indicating the role of micro-ecological factors and spatial heterogeneity in community assembly.

ecology↗

No branch left behind: tracking terrestrial biodiversity from a phylogenetic completeness perspective

Biodiversity, as we see it today, ultimately is the outcome of millions of years of evolution; however, biodiversity in its multiple dimensions is changing rapidly due to increasing human domination of Earth. Here, we present the "phylogenetic completeness" (PC) a concept and methodology that intends to safeguard Earths evolutionary heritage by maintaining all branches of the tree of life. We performed a global evaluation of the PC approach using data from five major terrestrial clades and compared the results to an approach in which species are conserved or lost randomly. We demonstrate that under PC, for a given number of species extinctions, it is possible to maximize the protection of evolutionary innovations in every clade. The PC approach is flexible and can be used to conduct a phylogenetic audit of biodiversity under different conservation scenarios. The PC approach complements existing conservation efforts and is linked to the post-2020 Convention of Biodiversity targets.

ecology↗

Predicting species distributions and community composition using remote sensing products

Accurate predictions of species composition and diversity are critical to the development of conservation actions and management strategies. In this paper using oak assemblages distributed across the conterminous United States as study model, we assessed the performance of stacked species distribution models (S-SDMs) and remote sensing products in building the next-generation of biodiversity models. This study represents the first attempt to evaluate the integrated predictions of biodiversity models, including assemblage diversity and composition, obtained by stacking next-generation SDMs. We found three main results. First, environmental predictors derived entirely from remote sensing products represent adequate covariates for biodiversity modeling. Second, applying constraints to assemblage predictions, such as imposing the probability ranking rule, results in more accurate species diversity predictions. Third, independent of the stacking procedure (bS-SDM versus cS-SDM), biodiversity models do not recover the observed species composition with high spatial resolution, i.e., correct species identities at the scale of individual plots. However, they do return reasonable predictions at macroecological scales (1 km). Our results provide insights for the prediction of assemblage diversity and composition at different spatial scales. An important task for future studies is to evaluate the reliability of combining S-SDMs with direct detection of species using image spectroscopy to build a new generation of biodiversity models to accurately predict and monitor ecological assemblages through time and space.Competing Interest StatementThe authors have declared no competing interest.View Full Text

ecology↗

Spatiotemporal dimensions of a reproductive life history trait in a spiny lizard radiation (Squamata: Phrynosomatidae)

The ecological and evolutionary factors underlying life history trait variation is one of the most interesting topics in biology. Although many studies have evaluated either macroevolutionary or macroecological patterns of life history traits across several taxonomic groups, only few studies have attempted to integrate both dimensions in a single analytical framework. Here, we study how parity mode evolved across multiple scales in the radiation of spiny lizards (Squamata: Phrynosomatidae). We adopted macroecological and macroevolutionary approaches to explore how climate across spatial and temporal scales drives the evolution of viviparity in this lizard radiation. We find support for a weak signature of current climates on the geographical distribution of oviparous and viviparous species. By contrast, we detected that evolutionary transitions from oviparity to viviparity reach a peak during the MidMiocene Climatic Optimum -- a period with a profound climate change event. We suggest that this abrupt climatic cooling promoted evolutionary transitions to viviparity simultaneously across three clades in the spiny lizard radiation. The decoupling in macroecological and macroevolutionary patterns found here suggests that past climate change has played a larger role than current climates in the spatial and temporal diversification of this reproductive life history trait.

evolutionary biology↗

HOW TO MEASURE THE INFLUENCE OF LANDSCAPE ON POPULATION GENETIC STRUCTURE: DEVELOPING RESISTANCE SURFACES USING A PATTERN-ORIENTED MODELING APPROACH

There are several approaches to understand how a landscape, with its several components, affects the genetic population structure by imposing resistance to gene flow. Here we propose the creation of resistance surfaces using a Pattern-Oriented Modeling approach to explain genetic differentiation, estimated by pairwise FST, among "Baruzeiro" populations (Dipteryx alata), a tree species widely distributed in Brazilian Cerrado. To establish the resistance surface, we used land use layers from the area in which the 25 "Baruzeiro" populations were sampled, generating 10000 resistance surfaces. To establish the resistance surface, we used land use layers from the area in which the 25 "Baru" populations were sampled, generating 10000 resistance surfaces. We randomized the cost values for each landscape component between 0 and 100. We use these surfaces to calculate pairwise matrices of the effective resistance among populations. Mantel test revealed a correlation of pairwise FST with a geographical distance equal to r = 0.48 (P < 0.001), whereas the Mantel correlations between pairwise FST and the generated resistance matrices ranged between r = -0.2019 and r= 0.6736. Partial regression on distance matrices was used to select the resistance matrix that provided the highest correlation with pairwise FST, based on the AIC criterion. The selected models suggest that the areas with lower resistance are characterized as natural savanna habitats of different forms, mainly arboreal dense savannas. In contrast, roads, big rivers, and agricultural lands cause higher resistance to gene flow.

genetics↗

Urban warming inverse contribution on risk of dengue transmission in the southeastern North America

O_LIPreventing diseases from becoming a problem where they are not is a common ground for disease ecology. The expectation for vector-borne diseases, especially those transmitted by mosquitos, is that warm and wet conditions favor vector traits increasing transmission potential. The advent of urbanization altering inner climate conditions hazards to increase mosquitos transmission potential on "disease-free" cooler areas as a consequence of a warming urban heat island (UHI) effect. C_LIO_LIWe assessed the realism of the anticipated dengue transmission potential into the southern United States in a causal pathway with the ongoing UHI effect, vectors spatial distribution patterns, and exogenous environment; We also measured the climatic niche similarity between both dengue vectors species. C_LIO_LIOur path model revealed that the UHI effect presents negative or no relation with dengue transmission potential. Instead, the surrounding non-urban temperature was rather suitable for the expected mosquitos transmission potential. C_LIO_LIBoth dengue vectors occurrence revealed to be more aggregated then expected by chance. These mosquitos density patterns were responsive to the warming effect of UHI-especially Aedes Aegypti-but not a reliable predictor for the anticipated dengue transmission potential pattern. The climatic niches of both vectors are not equivalent. Although currently highly overlapped, there is a wide space of their climatic niche still to be filled. C_LIO_LIPolicy implications. We highlight that the warming UHI effect on urban sites is not congruent with the expected suitability for dengue transmission. Instead, non-urban areas would be a better focus for dengue hazards into the southern United States. Our study also highlights the need for including low scale temperature on further mosquito-borne disease transmission models and track vectors niche filling under anthropogenic changes. C_LI

ecology↗

Testing Darwin's naturalization conundrum based on taxonomic, phylogenetic and functional dimensions of vascular plants

Charles Darwin posited two alternative hypotheses to explain the success of nonnative species based on their relatedness to incumbent natives: coexistence between them should be (i) more likely with greater relatedness (due to trait similarity that correlates with better matching to the environment), or (ii) less likely (due to biotic interference, such as competition). The paradox raised by the opposing predictions of these two hypotheses has been termed Darwins naturalization conundrum (DNC). Using plant communities measured repeatedly over a 31-year time span across an experimental fire gradient in an oak savanna (Minnesota, USA) we evaluated the DNC by explicitly incorporating taxonomic, functional and phylogenetic information. Our approach was based on focal-species such that the taxonomic, functional and phylogenetic structure of species co-occurring with a given nonnative species in local communities was quantified. We found three main results: first, nonnatives colonizers tended to co-occur most with closely related incumbent natives in recipient communities, except in the extreme ends of the fire gradient (i.e., communities with no fire and those subjected to high fire frequencies); second, with increasing fire frequency, nonnative species were functionally more similar to native species in recipient communities; third, functional similarity of co-occurring nonnatives and natives in recipient communities showed a consistent pattern over time, but the phylogenetic similarity shifted over time, suggesting that external forces (e.g., climate variability) are also relevant in driving the phylogenetic relatedness of nonnatives to natives in invaded communities. Our results provide insights for understanding the invasion dynamics across environmental gradients and highlight the importance of evaluating different dimensions of biodiversity in order to produce more powerful evaluations of species co-occurrence at different spatial and temporal scales.

ecology↗