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Topographic illumination Differential shading and brightness of reflectance
caused by land surface relief, i.e., relative slope exposure to direct sunlight.
Topology in phylogenetics, the structure of a phylogeny (dendrogram of evolutionary relationships among taxa).
Tracheid Specialized support and water transport cell in the xylem tissue of
plants. Tracheids have thick and rigid cell walls and are nonliving at maturity.
Conifers use tracheids for both water transport and mechanical support, whereas
angiosperms primarily use vessels for water transport and tracheids for mechanical support.
Trait A biochemical, physiological, morphological, structural, phenological, or
functional characteristic of a plant, population of plants, or community. Traits
exist on all levels of biological organization. See also functional trait.
Trait diversity Variation of traits on all levels of biological organization, generally calculated as a metric of the volume or breadth of the multidimensional
scatter of those traits. Trait diversity can be linked to phylogenetic, structural,
taxonomic, and functional diversity.
Transect A linear sampling approach used for quantifying number, size, species
composition, and other attributes of vegetation based on intersection with line of
fixed length.
Transmittance The fraction of light entering a leaf that is scattered out through
the opposite surface.
Transpiration The process by which liquid water is transported through plants
from roots to mesophyll tissue in leaves, where it evaporates and is released
through stomata (small pores on the underside of leaves) and to the atmosphere.
Tree of life The phylogeny—or inferred evolutionary relationships—of all species on Earth.
Trophic levels Positions of organisms on a food chain: organisms at higher trophic levels consume organisms at lower trophic levels.
TRY database Online repository for plant functional traits (https://www.trydb.org).
Uncertainty The probability (or value) of error regarding the data, algorithms, or
model outputs; also known as associated error.
Understory The vegetation below the canopy.
Unmanned aerial vehicle (UAV) or system (UAS) or device (UAD) An airborne
vehicle (drone) that can be flown without a human on board, including multicopters and fixed-wing aircraft.
Unsupervised classification The classification of remote sensing data without previously classified training or reference samples; mapped categories are
labeled or merged post hoc.
Upscaling Extrapolation from comparatively fine scales to larger areas, for example, through data aggregation or forward modeling. Contrast to downscaling.
User’s accuracy The fraction of correctly classified pixels with regard to the
classes present on the ground. Contrast to producer’s accuracy.
Vacuole A membrane-bound organelle within the plant cell that stores water,
enzymes, and other organic molecules, sometimes including toxins or waste
Glossary
Topographic illumination Differential shading and brightness of reflectance
caused by land surface relief, i.e., relative slope exposure to direct sunlight.
Topology in phylogenetics, the structure of a phylogeny (dendrogram of evolutionary relationships among taxa).
Tracheid Specialized support and water transport cell in the xylem tissue of
plants. Tracheids have thick and rigid cell walls and are nonliving at maturity.
Conifers use tracheids for both water transport and mechanical support, whereas
angiosperms primarily use vessels for water transport and tracheids for mechanical support.
Trait A biochemical, physiological, morphological, structural, phenological, or
functional characteristic of a plant, population of plants, or community. Traits
exist on all levels of biological organization. See also functional trait.
Trait diversity Variation of traits on all levels of biological organization, generally calculated as a metric of the volume or breadth of the multidimensional
scatter of those traits. Trait diversity can be linked to phylogenetic, structural,
taxonomic, and functional diversity.
Transect A linear sampling approach used for quantifying number, size, species
composition, and other attributes of vegetation based on intersection with line of
fixed length.
Transmittance The fraction of light entering a leaf that is scattered out through
the opposite surface.
Transpiration The process by which liquid water is transported through plants
from roots to mesophyll tissue in leaves, where it evaporates and is released
through stomata (small pores on the underside of leaves) and to the atmosphere.
Tree of life The phylogeny—or inferred evolutionary relationships—of all species on Earth.
Trophic levels Positions of organisms on a food chain: organisms at higher trophic levels consume organisms at lower trophic levels.
TRY database Online repository for plant functional traits (https://www.trydb.org).
Uncertainty The probability (or value) of error regarding the data, algorithms, or
model outputs; also known as associated error.
Understory The vegetation below the canopy.
Unmanned aerial vehicle (UAV) or system (UAS) or device (UAD) An airborne
vehicle (drone) that can be flown without a human on board, including multicopters and fixed-wing aircraft.
Unsupervised classification The classification of remote sensing data without previously classified training or reference samples; mapped categories are
labeled or merged post hoc.
Upscaling Extrapolation from comparatively fine scales to larger areas, for example, through data aggregation or forward modeling. Contrast to downscaling.
User’s accuracy The fraction of correctly classified pixels with regard to the
classes present on the ground. Contrast to producer’s accuracy.
Vacuole A membrane-bound organelle within the plant cell that stores water,
enzymes, and other organic molecules, sometimes including toxins or waste
Glossary