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Parameter A value (generally held constant in a given model or equation) describing a phenomenon of interest. Contrast to variable.
Parameterization The process of defining or selecting parameters for equations
or sets of equations (models) to explain or describe phenomena of interest.
Parenchyma Living thin-walled, relatively unspecialized (undifferentiated) cells
or tissues. In leaves, parenchyma cells comprise the mesophyll and can be modified to perform more specific functions. Parenchyma tissue may be compact,
as in the palisade parenchyma, or have large spaces between the cells, as in the
spongy mesophyll.
Partial least squares regression (PLSR) A predictive statistical regression
method that is used to find the fundamental relations between a predictor variable
matrix (X) and dependent variable matrix (Y) based on identifying an optimal
set of latent vectors descriptive of the variable of interest. PLSR is widely used
in chemometrics and is especially useful when the number of predictor variables
(e.g., spectral measurements) is large compared to the number of observations.
Passive optical remote sensing The measurement of optical signatures or reflectance from an object or phenomenon by a sensor that is not in physical contact
with the object. Passive remote sensing systems depend on solar illumination or
thermal emission (i.e., they do not generate their own energy for measurement).
Passive sensor A sensor that does not require active or pulsed light emission
but uses solar irradiance or thermal emission to detect the feature or objects of
interest.
Petiole The specialized stalk that attaches the plant leaf blade to the stem, containing vascular tissues and providing structural support.
PhenoCam A webcam for monitoring vegetation phenology. Also, the name for a
vegetation phenology network based on webcams.
Phenogram Depiction of a phylogenetic tree where one axis represents trait values and the other axis represents time.
Phenol Organic compound containing the basic structural unit C 6 H 5 OH.
Phenology The study of periodic, seasonal processes such as budbreak, flowering, seed maturation, leaf senescence, and leaf fall in plants. Although most typically used for visible events or processes, the term is also increasingly applied
to less visible, seasonally changing processes, as in “photosynthetic phenology.”
Phenological types Species groupings based on regularity, date of onset, and
duration of phenological cycles.
Phenome A phenologically similar terrestrial zones or the set of phenotypes
(physical and biochemical traits) that can be produced by a given organism over
the course of development and in response to genetic mutation and environmental influences.
Phenomics The study or measurement of phenotypes that often uses proximal
remote sensing (typically cameras, imaging spectrometers, or other devices) to
sample and distinguish plant features.
Phenotype The observable aspects of an organism, population, or biological
entity. Contrast with genotype. While phenotype depends on genotype, the interaction of the genotype with the environment determines the phenotype.
Glossary
Parameter A value (generally held constant in a given model or equation) describing a phenomenon of interest. Contrast to variable.
Parameterization The process of defining or selecting parameters for equations
or sets of equations (models) to explain or describe phenomena of interest.
Parenchyma Living thin-walled, relatively unspecialized (undifferentiated) cells
or tissues. In leaves, parenchyma cells comprise the mesophyll and can be modified to perform more specific functions. Parenchyma tissue may be compact,
as in the palisade parenchyma, or have large spaces between the cells, as in the
spongy mesophyll.
Partial least squares regression (PLSR) A predictive statistical regression
method that is used to find the fundamental relations between a predictor variable
matrix (X) and dependent variable matrix (Y) based on identifying an optimal
set of latent vectors descriptive of the variable of interest. PLSR is widely used
in chemometrics and is especially useful when the number of predictor variables
(e.g., spectral measurements) is large compared to the number of observations.
Passive optical remote sensing The measurement of optical signatures or reflectance from an object or phenomenon by a sensor that is not in physical contact
with the object. Passive remote sensing systems depend on solar illumination or
thermal emission (i.e., they do not generate their own energy for measurement).
Passive sensor A sensor that does not require active or pulsed light emission
but uses solar irradiance or thermal emission to detect the feature or objects of
interest.
Petiole The specialized stalk that attaches the plant leaf blade to the stem, containing vascular tissues and providing structural support.
PhenoCam A webcam for monitoring vegetation phenology. Also, the name for a
vegetation phenology network based on webcams.
Phenogram Depiction of a phylogenetic tree where one axis represents trait values and the other axis represents time.
Phenol Organic compound containing the basic structural unit C 6 H 5 OH.
Phenology The study of periodic, seasonal processes such as budbreak, flowering, seed maturation, leaf senescence, and leaf fall in plants. Although most typically used for visible events or processes, the term is also increasingly applied
to less visible, seasonally changing processes, as in “photosynthetic phenology.”
Phenological types Species groupings based on regularity, date of onset, and
duration of phenological cycles.
Phenome A phenologically similar terrestrial zones or the set of phenotypes
(physical and biochemical traits) that can be produced by a given organism over
the course of development and in response to genetic mutation and environmental influences.
Phenomics The study or measurement of phenotypes that often uses proximal
remote sensing (typically cameras, imaging spectrometers, or other devices) to
sample and distinguish plant features.
Phenotype The observable aspects of an organism, population, or biological
entity. Contrast with genotype. While phenotype depends on genotype, the interaction of the genotype with the environment determines the phenotype.
Glossary