Fernando Valencia results 48
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Aim Plant functional traits can influence interaction outcomes between nurse and target plants through a “functional trait match”, which occurs when the traits of nurse plants ameliorate their environment, and target plants possess traits that allow them to benefit from this ameliorated environment. We investigated how the traits of putative nurse species affect interaction outcomes across global drylands and determined the fu...
Antimicrobial and Photocatalytic Potential of a Composite of ZnO-ZnS and Activated Carbon Obtained From Banana PeelNARA Subscribed
Banana peel was mixed with zinc sulfate and pyrolyzed at 500 °C under nitrogen to synthesize a composite with potential antibacterial activity against both Gram-positive Escherichia coli and Gram-negative Staphylococcus aureus . The material was characterized by TGA, nitrogen adsorption-desorption isotherm, SEM-EDX, DRX, DRS UV-Vis, and DLS. XRD analysis showed the presence of ZnO and ZnS in the composite, and TGA analysis rev...
The Relationship Between Grazing Pressure and Environmental Factors Drives Vegetation Fragmentation Across Global DrylandsNARA Subscribed
Aim To evaluate how grazing pressure, a key land‐use factor, interacts with climatic, vegetation, and soil variables to shape the fragmentation of perennial vegetation across drylands globally. Location 171 plots across 25 countries on six continents. Time Period Field data: 2016–2019. Major Taxa Studied Perennial grasses, shrubs, and woody plants. Methods We conducted a standardised field survey across 171 45 m × 45 m plots t...
Plants can facilitate their local environment and create a two‐phase spatial structure of vegetation and bare soil in drylands, which largely influences ecosystem functioning. Although an increasing number of studies have examined how global change drivers like aridity influence vegetation spatial structure in drylands (e.g., the patch size distribution), it remains unclear how grazing impacts differ from those of climatic gra...
Our primary objective was to compile a comprehensive dataset on bird–window collisions throughout the Neotropical region, including both published and unpublished sources. On May 12, 2020, we extensively disseminated invitations to provide data via email and social media platforms. By providing a template worksheet, we required standardized information from collaborators to complete and register their data. To better understan...
Dominance and rarity in tree communities across the globe: Patterns, predictors and threatsNARA Subscribed
Aim Ecological and anthropogenic factors shift the abundances of dominant and rare tree species within local forest communities, thus affecting species composition and ecosystem functioning. To inform forest and conservation management it is important to understand the drivers of dominance and rarity in local tree communities. We answer the following research questions: (1) What are the patterns of dominance and rarity in tree...
Carbon Dioxide and Nitrous Oxide Emissions from a Typical Sugarcane Soil in the Cauca River Valley, ColombiaNARA Subscribed
Sugarcane is an important crop for tropical countries and to accurately inventory its greenhouse gas (GHG) emissions baseline measurements are needed. In Colombia, sugarcane is one of the most important crops in terms of cultivated area and, paradoxically, scientific information reporting GHG emissions based on field measurements is almost nonexistent. The objective of this work was to quantify the direct emissions of carbon d...
Phenology has long been hypothesized as an avenue for niche partitioning or interspecific facilitation, both promoting species coexistence. Tropical plant communities exhibit striking diversity in reproductive phenology, but many are also noted for large synchronous reproductive events. Here we study whether the phenology of seed fall in such communities is nonrandom, the temporal scales of phenological patterns, and ecologica...
Purpose Biocrust communities, which are important regulators of multiple ecosystem functions in drylands, are highly sensitive to climate change. There is growing evidence of the negative impacts of warming on the performance of biocrust constituents like lichens in the field. Here, we aim to understand the physiological basis behind this pattern. Methods Using a unique manipulative climate change experiment, we monitored ever...
Distinguishing among the mechanisms underlying the spatial distribution of genetic variation resulting from the environmental or physical barriers from those arising due to simple geographic distance is challenging in complex landscapes. The Andean uplift represents one of the most heterogeneous habitats where multiple mechanisms may interact, confounding their relative roles. We explore this broad question in the leaf‐cutting...
Demographic composition, not demographic diversity, predicts biomass and turnover across temperate and tropical forestsNARA Subscribed
The growth and survival of individual trees determine the physical structure of a forest with important consequences for forest function. However, given the diversity of tree species and forest biomes, quantifying the multitude of demographic strategies within and across forests and the way that they translate into forest structure and function remains a significant challenge. Here, we quantify the demographic rates of 1961 tr...
Unsustainable fisheries practices carried out in large parts of the Amazon, Tocantins, and Orinoco basins have contributed to the decline in the populations of the Amazon River dolphins ( Inia spp.), considered Endangered by the International Union for Conservation of Nature (IUCN). Amazon River dolphin byproducts are often obtained through unregulated fisheries and from stranded and incidentally caught individuals that are tr...