発表論文

Reflectance and transmittance spectra of leaves and shoots of 22 vascular plant species and reflectance spectra of trunks and branches of 12 tree species in Japan

著者
Noda H., Motohka T., Murakami K., Muraoka H., Nasahara K.
雑誌名
Ecol. Res.
DOI
10.1007/s11284-013-1096-z
概要
This data paper reports spectral reflectance and transmittance data of leaves from 21 terrestrial vascular plant species (seven herbaceous, and 14 broadleaf and long-needle coniferous tree species) and of shoots from one short-needle coniferous tree species. The reflectance spectra of branches of one tree species, of the trunks of 12 tree species and ground surface of one deciduous broad-leaf forest are also reported. Optical measurements and leaf samplings were made at five sites on Honshu Island, Japan, which are typical vegetation types in East Asia, i.e., grassland, paddy field, and deciduous broad-leaf or coniferous forests. The collection and measurements were conducted for main species in each site. To include other common vegetation types in East Asia, such as evergreen broad-leaf or coniferous forests, the sample collection and the measurements were conducted at gardens and an experimental forest. Leaves of ten deciduous species were measured at different phenological stages from leaf expansion to senescence since those species shows significant seasonal changes in spectral reflectance and transmittance of leaves. Leaves at different position in a canopy (e.g., sunlit versus shaded leaves) were also measured for eight of 21 species. The spectral reflectance and transmittance from both adaxial and abaxial sides of the all leaves or needles, expect Picea abies needles. The measurements of the leaves were conducted with a spectroradiometer attached via an optical fiber to an integrating sphere. Two types of integrating spheres were used: a model LI-1800-12 (Li-Cor) and an RTS-3ZC integrating sphere (Analytical Spectral Devices). A leaf clip accessory was also used instead of an integrating sphere for measuring the leaves of two species. All data were measured within the 350–2,500-nm spectral range with 1-nm steps between measurements but the data obtained by LI-1800 is unavailable in 1,650–1,740, 1,890–1,950, and 2,050–2,500 nm because of a large amount of noise. These data are used as input parameters in a radiative transfer model designed to estimate the leaf area index from radiation reflected from a canopy surface.
植物群落の分光反射特性(光が当たった際に反射する割合の波長ごとの分布)は、群落を構成する個葉の分光反射率・透過率および幹・枝の分光反射率に規定される。また、個葉の分光特性は葉の生化学的な特性(クロロフィル量や含水率など)と解剖学的な特性を反映している。したがって葉と幹・枝の分光特性データは、人工衛星や航空機等のリモートセンシングによる分光データを生態学的に解釈する上で不可欠である。葉や幹・枝の分光特性は植物種により異なり、さらに葉の分光特性は季節により変化する。いくつかのデータベースで個葉の分光特性データは公開されているが、日本に生育する種はほとんど含まれておらず、季節性も考慮されていない。そこで、日本を含む東アジアの代表的な植生の優占種を中心に、季節性も含めた分光データを公開するため、複数の季節に測定したデータを含む維管束植物22種の葉・シュートの分光反射・透過率と12種の幹・枝の分光反射率データをデータペーパー(データ本体と詳細情報を公表する論文)として報告した。