Paper · 2019 · DOAJ (DOAJ: Directory of Open Access Journals)

Optical evaluation of the shading properties of climbing fern Lygodium japonicum used as thermal buffering green wall plant

Hara, A.; Takaichi, H.; Murata, Y.; et al.

6
claims
11
verbatim quotes
0
citations
2
research areas
✓
Open access · cc-by-sa

Abstract

Recently, thermal properties of the landscaped rooftops and walls have attracted the interest of researchers because of the potential to minimize energy consumption in urban areas and to aid summer-time thermal control. For this reason the creation of a plant-based shade for walls or above buildings is highly important. In this paper we evaluate using Lygodium japonicum, one of the many ferns and fern allies traditionally used in Japanese gardening, as a component of thermal-buffering green walls. Lygodium japonicum, the only climbing fern species in Japan, is fast-growing, adheres easily to walls and has a climbing nature. A simple thermal analysis of the sun-shading effect of Lygodium canopy suggested that local surface temperature above the ceramic tiles placed on the rooftop of a building can be buffered (lowered in daytime and maintained relatively warm at night) by the presence of leafy climbing ferns covering the tiles, possibly due to the reflection and absorbance of solar radiation. Furthermore, the presence of the plants may also slow the night-time release of heat from the building surface. Because plants installed on tall walls or on the tops of buildings are not easily accessed for manual care, we performed a real-time routine monitoring and control of plant growth status using various optical sensors that could be automated and monitored remotely for large-scale applications. For this purpose, the optical properties of a Lygodium canopy under solar incident light have been determined. In order to evaluate the natural shading and growing properties of a green canopy, the incident solar radiation spectrum (J), leaf canopy-filtered light spectrum (transmittance, T) and leaf-reflectivity spectrum ® were measured. By reading the reflectivity spectrum, concomitant chlorophyll fluorescence signals (F) from Lygodium leaves were also detected at 760 nm, which corresponds to the O2-A Fraunhofer line. Our data suggests that the daily change in photosynthetic status (P) can be traced by monitoring the change in relative F in relation to the estimated heat loss (H) and measured J, R, and T using a series of practical equations designed to roughly estimate the gross photosynthetic response within the plant canopy. Using our equations, the photosynthetic capacity in the plant canopy structure could be simply simulated and predictable by optical sensors.

Abstract from the paper’s OpenAlex record; open copy licensed cc-by-sa. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.

Claims 6

Associationauthor interpretationoriginal resultsimulated

Claim · model-written summary

Lygodium canopy was predicted to lower daytime rooftop tile temperature.

Taxon
Lygodium japonicumLygodium japonicumt0
Outcome
local surface temperature above the ceramic tilese0
Direction
lowerede0
Qualifier
daytimee0
Setting
rooftop of a buildinge0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lygodium japonicum
Lygodium japonicum · Taxonharum.koh from Kobe city, Japan · CC BY-SA 2.0 · Wikimedia Commons ↗

Verbatim

e0

“local surface temperature above the ceramic tiles placed on the rooftop of a building can be buffered (lowered in daytime and maintained relatively warm at night) by the presence of leafy climbing ferns covering the tiles”

✓ located verbatim in the source · abstract, characters 718–939 · show in text ↑
t0

“climbing fern Lygodium japonicum”

✓ located verbatim in the source · title, characters 48–80 · show in text ↑

schema checkedfield values found in the cited quotesPermalinkReport an issue

Associationauthor interpretationoriginal resultsimulated

Claim · model-written summary

Lygodium canopy was predicted to keep rooftop tiles relatively warm at night.

Taxon
Lygodium japonicumLygodium japonicumt0
Outcome
local surface temperature above the ceramic tilese0
Direction
maintained relatively warme0
Qualifier
at nighte0
Setting
rooftop of a buildinge0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lygodium japonicum
Lygodium japonicum · Taxonharum.koh from Kobe city, Japan · CC BY-SA 2.0 · Wikimedia Commons ↗

Verbatim

e0

“local surface temperature above the ceramic tiles placed on the rooftop of a building can be buffered (lowered in daytime and maintained relatively warm at night) by the presence of leafy climbing ferns covering the tiles”

✓ located verbatim in the source · abstract, characters 718–939 · show in text ↑
t0

“climbing fern Lygodium japonicum”

✓ located verbatim in the source · title, characters 48–80 · show in text ↑

schema checkedfield values found in the cited quotesPermalinkReport an issue

Associationhypothesisoriginal resultsimulated

Claim · model-written summary

Fern cover may slow night-time release of heat from the building surface.

Taxon
Lygodium japonicumLygodium japonicumt0
Outcome
night-time release of heat from the building surfacee0
Direction
slowe0
Qualifier
maye0
Setting
building surfacee0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lygodium japonicum
Lygodium japonicum · Taxonharum.koh from Kobe city, Japan · CC BY-SA 2.0 · Wikimedia Commons ↗

Verbatim

e0

“the presence of the plants may also slow the night-time release of heat from the building surface”

✓ located verbatim in the source · abstract, characters 1020–1117 · show in text ↑
t0

“climbing fern Lygodium japonicum”

✓ located verbatim in the source · title, characters 48–80 · show in text ↑

schema checkedfield values found in the cited quotesPermalinkReport an issue

Observationobservedoriginal resultmeasured

Claim · model-written summary

Chlorophyll fluorescence from Lygodium leaves was detected at 760 nm in reflectivity spectra.

Taxon
LygodiumLygodiume0
Organ / stage
leavese0
Outcome
chlorophyll fluorescence signals (F)e0
Value
760 nme0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lygodium
Lygodium · Taxon · picture of the genus (one of its species)No machine-readable author provided. Keisotyo assumed (based on copyright claims). · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“chlorophyll fluorescence signals (F) from Lygodium leaves were also detected at 760 nm”

✓ located verbatim in the source · abstract, characters 1803–1889 · show in text ↑
Method / resourceauthor interpretationoriginal resultsimulated

Claim · model-written summary

Relative fluorescence and optical measurements may trace daily photosynthetic status in Lygodium.

Taxon
Lygodium japonicumLygodium japonicumt0
Outcome
daily change in photosynthetic status (P)e0
Qualifier
monitoring the change in relative F in relation to the estimated heat loss (H) and measured J, R, and Te0

Not reportedComparatorValue

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lygodium japonicum
Lygodium japonicum · Taxonharum.koh from Kobe city, Japan · CC BY-SA 2.0 · Wikimedia Commons ↗

Verbatim

e0

“daily change in photosynthetic status (P) can be traced by monitoring the change in relative F in relation to the estimated heat loss (H) and measured J, R, and T using a series of practical equations”

✓ located verbatim in the source · abstract, characters 1965–2165 · show in text ↑
t0

“climbing fern Lygodium japonicum”

✓ located verbatim in the source · title, characters 48–80 · show in text ↑
Method / resourceauthor interpretationoriginal resultsimulated

Claim · model-written summary

Equations allowed simple simulation and optical prediction of fern canopy photosynthetic capacity.

Taxon
Lygodium japonicumLygodium japonicumt0
Outcome
photosynthetic capacity in the plant canopy structuree0

Not reportedComparatorValue

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lygodium japonicum
Lygodium japonicum · Taxonharum.koh from Kobe city, Japan · CC BY-SA 2.0 · Wikimedia Commons ↗

Verbatim

e0

“photosynthetic capacity in the plant canopy structure could be simply simulated and predictable by optical sensors”

✓ located verbatim in the source · abstract, characters 2279–2393 · show in text ↑
t0

“climbing fern Lygodium japonicum”

✓ located verbatim in the source · title, characters 48–80 · show in text ↑