Leaf spectra of four broadleaved deciduous tree species in Finland

This dataset contains measurements of leaf reflectance and transmittance spectra of four broadleaved deciduous tree species from Southern Finland. The measurements were conducted between 8th and 23rd June 2022, when the leaves were fully developed. The sampled tree species were common aspen (Populus tremula L.), goat willow (Salix caprea L.), grey alder (Alnus incana (L.) Moench) and common alder (Alnus glutinosa (L.) Gaertn.). The trees grew in forests. Branches were detached from the trees using scissors attached to a telescope bar. Altogether, 48 branches were sampled per species: six branches from each of the eight sample trees per species. Three branches per tree were sampled from the upper (i.e., sunlit) part of the crown and three from the lower (i.e., shaded or partly shaded) part of the crown. One healthy green leaf was selected in a systematic way from each branch. Leaf directional-hemispherical reflectance and transmittance were measured both from the adaxial (upper) and abaxial (lower) side of each sample leaf. The height and diameter at breast height (1.3 m) were recorded from each tree. If you use this dataset, please cite: Kuusinen, N., Lakaniemi, E., Hovi A., Rautiainen, M. 2022. Leaf spectra of four broadleaved deciduous tree species in Finland. Mendeley Data, V1, doi: 10.17632/3hswxj5nff.1. The collection of the data is described in Data_description.pdf. Comma separated (csv) files named as reflectance_adaxial.csv, reflectance_abaxial.csv, transmittance_adaxial.csv and transmittance_abaxial.csv contain reflectance spectra of the adaxial and abaxial leaf sides and transmittance spectra of the adaxial and abaxial leaf sides, respectively, in wavelength range 350-2500 nm. samples.csv contains information for each sample as explained in Data_description.pdf.本数据集包含芬兰南部4种阔叶落叶树种的叶片反射率与透射光谱测量数据。测量工作于2022年6月8日至23日开展，此时叶片已完全舒展。 本次采样涉及的树种分别为欧洲山杨（Populus tremula L.）、山羊柳（Salix caprea L.）、灰桤木（Alnus incana (L.) Moench）以及欧洲桤木（Alnus glutinosa (L.) Gaertn.）。所有供试树木均生长于天然林分中。研究人员借助安装在伸缩杆上的剪刀截取枝条：每个物种共采集48根枝条，即每个物种选取8棵样树，每棵树采集6根枝条，其中3根采自树冠上部（受光区域），剩余3根采自树冠下部（遮阴或半遮阴区域）。 从每根枝条上系统选取1片健康的绿色叶片，对每片样品叶的近轴面（adaxial）与远轴面（abaxial）分别测定方向-半球反射率（directional-hemispherical reflectance）与透射率。同时记录每棵样树的树高与胸径（diameter at breast height，1.3米处）。 若使用本数据集，请引用如下文献： Kuusinen, N., Lakaniemi, E., Hovi A., Rautiainen, M. 2022. Leaf spectra of four broadleaved deciduous tree species in Finland. Mendeley Data, V1, doi: 10.17632/3hswxj5nff.1. 本数据集的数据采集详情见Data_description.pdf。4个逗号分隔的CSV文件分别为reflectance_adaxial.csv、reflectance_abaxial.csv、transmittance_adaxial.csv与transmittance_abaxial.csv，依次对应叶片近轴面反射光谱、叶片远轴面反射光谱、叶片近轴面透射光谱以及叶片远轴面透射光谱，光谱波长范围为350~2500 nm。samples.csv文件包含每份样品的相关信息，具体说明见Data_description.pdf。