370
minimal, while the gain in absorption by the detour effect is large. The detour effect
can increase absorption at 550 nm sufficient to rival absorption in blue and red
bands for photosynthesis. Such interactions make quantifying the concentrations of
specific compounds and correctly attributing their impact on physiological processes subject to potentially significant errors. Despite difficulties in separating the
effect of each pigment in the leaf, the in vivo spectral shapes of different species are
fairly conservative within related taxa and are often distinctive of the taxonomic
group over much of the wavelength region between 450 nm and 700 nm; these patterns have been used to identify genera, species, and even phenotypes (Asner and
Martin 2016; Junker and Ensminger 2016).
14.8.7 Non-photosynthetic Pigments
Anthocyanins are a diverse group (more than 540 pigments identified in nature;
Anderson and Francis 2004) of colored, water-soluble flavonoids found in the vacuoles of many seed plants (Hrazdina et al. 1978). Pigment colors range from blue to
red, depending on pH. Anthocyanins have been associated with many benefits to
plants (Lee and Gould 2002). They attract pollinators and animals that disperse
seeds and fruits, protect plants growing at high elevations from UV light, and protect against cold (Chalker-Scott 1999; Lee 2000). Anthocyanins are common in
understory plants (Lee 2002). The protective mechanism of anthocyanins in leaves
develops during early stages of leaf expansion (e.g., young leaves in Fig. 14.2)
before leaves are photosynthetically functional in some species (Landi et al. 2015).
Lee and Collins (2001) showed within-family phylogenetic relationships of anthocyanins for 399 woody tropical taxa. Other flavonoids also contribute to physiological regulation, providing chemical signals to other parts of the plant or to other
plants, or promoting or inhibiting interactions with other organisms. Because of
their strong absorption in the red wavelengths, anthocyanins can be confused with
chlorophylls, resulting in overestimation of photosynthetic capacity. Gitelson et al.
(Gitelson 2012) developed semi-analytic three-band models to separately estimate
the concentrations of chlorophylls, carotenoids, and anthocyanin foliar pigments. In
collaboration with Gitelson, Féret et al. (2017) updated most recent PROSPECT-D
model (Féret et al. 2017) fusing a linear relationship among six independent data
sets between predicted and measured anthocyanin. Féret et al. (2017) improved the
specific absorption coefficients for chlorophylls, carotenoids, and anthocyanins as
shown in Fig. 14.10.
14.8.8 Brown Pigments
When pigments and their protein complexes degrade, they form colored chemical
residues. These are poorly described but constitute the “brown” pigments or colored
pigment residues in the leaf when it senesces and dies. These result from oxidation
S. L. Ustin and S. Jacquemoud
minimal, while the gain in absorption by the detour effect is large. The detour effect
can increase absorption at 550 nm sufficient to rival absorption in blue and red
bands for photosynthesis. Such interactions make quantifying the concentrations of
specific compounds and correctly attributing their impact on physiological processes subject to potentially significant errors. Despite difficulties in separating the
effect of each pigment in the leaf, the in vivo spectral shapes of different species are
fairly conservative within related taxa and are often distinctive of the taxonomic
group over much of the wavelength region between 450 nm and 700 nm; these patterns have been used to identify genera, species, and even phenotypes (Asner and
Martin 2016; Junker and Ensminger 2016).
14.8.7 Non-photosynthetic Pigments
Anthocyanins are a diverse group (more than 540 pigments identified in nature;
Anderson and Francis 2004) of colored, water-soluble flavonoids found in the vacuoles of many seed plants (Hrazdina et al. 1978). Pigment colors range from blue to
red, depending on pH. Anthocyanins have been associated with many benefits to
plants (Lee and Gould 2002). They attract pollinators and animals that disperse
seeds and fruits, protect plants growing at high elevations from UV light, and protect against cold (Chalker-Scott 1999; Lee 2000). Anthocyanins are common in
understory plants (Lee 2002). The protective mechanism of anthocyanins in leaves
develops during early stages of leaf expansion (e.g., young leaves in Fig. 14.2)
before leaves are photosynthetically functional in some species (Landi et al. 2015).
Lee and Collins (2001) showed within-family phylogenetic relationships of anthocyanins for 399 woody tropical taxa. Other flavonoids also contribute to physiological regulation, providing chemical signals to other parts of the plant or to other
plants, or promoting or inhibiting interactions with other organisms. Because of
their strong absorption in the red wavelengths, anthocyanins can be confused with
chlorophylls, resulting in overestimation of photosynthetic capacity. Gitelson et al.
(Gitelson 2012) developed semi-analytic three-band models to separately estimate
the concentrations of chlorophylls, carotenoids, and anthocyanin foliar pigments. In
collaboration with Gitelson, Féret et al. (2017) updated most recent PROSPECT-D
model (Féret et al. 2017) fusing a linear relationship among six independent data
sets between predicted and measured anthocyanin. Féret et al. (2017) improved the
specific absorption coefficients for chlorophylls, carotenoids, and anthocyanins as
shown in Fig. 14.10.
14.8.8 Brown Pigments
When pigments and their protein complexes degrade, they form colored chemical
residues. These are poorly described but constitute the “brown” pigments or colored
pigment residues in the leaf when it senesces and dies. These result from oxidation
S. L. Ustin and S. Jacquemoud