Solar radiation (SR) dynamics have a profound effect on plant growth, development, and ecosystems, and they act as a primary energy source and important environmental signal that plants perceive through their photoreceptors, which primarily sense critical wavelength ratios (CWRs). The diffuse fraction of solar radiation (DF) is a key factor affecting the quality and distribution of light within the plant canopy. We analyzed one year of SR spectral observations measured by a ground-based rotating shadow-band spectroradiometer to evaluate the potential effects of DF and CWRs on plants in an outdoor environment in Fukuoka, Japan. The daily mean DF and all considered CWRs showed significant seasonal variations regardless of the solar meridian altitude. Cloudy or partly cloudy skies were prevalent throughout the year. The ratios of ultraviolet-A (UV-A)/UV-B, red (R)/blue (B), and R/green (G) increased during winter and decreased during summer. Conversely, the ratios of photosynthetically active radiation (PAR)/global solar radiation (GSI), UV/GSI, UV/PAR, B/G, R/far-red (FR), and UV-B/B increased during summer and decreased during winter. Most of the CWR correlated with DF. Furthermore, our study discovered a synergistic influence of air mass (AM), water vapor pressure (VP), and DF on specific CWRs, which play a crucial role in plant light signal processing. This highlights the potential influence of AM, VP, and DF on plant light signals, thereby opening avenues for developing innovative plant growth models and ecological responses incorporating plant photoreception.

The International Union for Conservation of Nature (IUCN) has recently developed a global ecosystem typology (IUCN typology) based on the functional characteristics of the ecosystems. However, its low spatial resolution and lack of recognition of certain categories in Japan limits effective and precise habitat analysis for global comparisons. In this data paper, we used the Japanese vegetation map provided by the Ministry of Environment (MOE) to align Japanese vegetation categories with the IUCN typology scheme up to Level 4, Regional subgroups, developing a correspondence table and a high-resolution spatial dataset focusing on terrestrial ecosystems. In addition, we also integrated the land-use classification developed by the National Institute for Environmental Studies. The dataset includes tables describing the integration of Japanese habitat classification with IUCN typology from Level 1 to 4 (Realms, Biomes, Ecosystem functional groups, Regional subgroups), explanation of land-use categories, and the main corresponding table as well as high-resolution integrated GIS data. This integration supports both global and local studies, with the tables including English and Japanese names of the classification tree.

Industrial oil palm plantations threaten biodiversity in Southeast Asia, yet some native species are highly adaptable within these environments. Our study investigates the space use of leopard cats (Prionailurus javanensis) within oil palm plantations adjacent to degraded forest fragments in the Kinabatangan floodplain, Sabah, Malaysian Borneo. From March to September 2020, we captured and collared four male cats with GPS collars, accumulating a total of 13,206 successful locational points. We estimated the home ranges using the Minimum Convex Polygon (MCP) and adaptative Localised Convex Hull (a-LoCoH) methods. The average home ranges were 8.60 km² ± 1.98 (± SD) [95% MCP] and 5.39 km² ± 1.23 [95% a-LoCoH], with corresponding core areas of 2.55 km² ± 0.99 (± SD) [50% MCP] and 1.05 km² ± 0.30 [50% a-LoCoH]. The home ranges of male leopard cats overlapped (7% to 28%), while core areas remained exclusive. Despite significant variations in individual habitat use, these cats were detected more frequently in oil palm habitat, occupying 80.89% of their home range and 78.38% of core area. Interestingly, they relied more on buffer zones contiguous to plantation area rather than adjacent secondary forests, highlighting the importance of preserving High Conservation Value (HCV) forests.

Plateau pikas cause changes in alpine meadow biodiversity and consequently impair ecosystem function through foraging, burrowing and defecation. However, existing studies often focus on a limited number of taxa, ignoring the fact that biodiversity loss occurs across many taxa and that the functional effects of any trophic group may depend on the diversity of other trophic groups. In this study, we analyzed the effects of disturbance by plateau pika on the diversity of organisms (plants, earthworms, ciliates, fungi and bacteria) and ecosystem multifunctionality (EMF) in different trophic groups. The results showed that: (1) disturbance by plateau pika significantly altered multi-trophic biodiversity and simultaneously affected EMF. (2) Plant species richness (25.52%) and functional richness (22.25%) were the most important factors driving EMF, followed by higher trophic level soil ciliates (18.35%) and earthworms (14.03%), and lower trophic level soil bacteria (9.88%), fungi, fungi, and bacteria (9.88%). Bacterial (9.88%) richness at lower trophic levels also drove EMF. (3) The relationship between biodiversity and EMF at each trophic level changed when the density of active burrows of plateau pikas was around 550 burrows/ha. At lower burrow densities (<530 burrows/ha), soil biodiversity had a greater effect on EMF, while at higher densities (>575 burrows/ha), plant diversity was more critical to EMF. (4) Disturbance by plateau pika had a negative effect on EMF, explaining 68% of the variation in EMF. This study reveals the important role of higher trophic level biodiversity in maintaining ecosystem function under the disturbance of plateau pika.

Although the amount of acidic deposition has recently decreased in Japan, acid deposition has deteriorated some forest ecosystems during the past few decades. We investigated the yearly variations in stream water chemistry for more than 20 years in two areas (Yusuhara and Taisho) in the Shmanto River Basin, southern Japan, where the effects of acidic deposition are considered to be modest. Stream water samples were collected monthly from three forest watersheds selected at each site. The annual means of the stream chemistry were predicted by multiple regression analysis. The sunlight hours were positively related with the potassium, magnesium, calcium, nitrate, sulfate, and bicarbonate concentrations in stream water. The results suggest that long sunlight hours boost the photosynthetic activities, thus promoting soil respiration and decomposition of soil organic matter; moreover, a higher carbonic acid concentration in the soil solution promotes cation weathering and carbonic acid dissociation to bicarbonate. The ammonium, nitrate, and sulfate concentrations in the bulk precipitation have decreased at Yusuhara and the sodium, magnesium, calcium, chloride, nitrate, and sulfate concentrations in the stream water have decreased in both areas. The nitrate and sulfate concentrations apparently responded to the decreasing input of acidic deposition. Given the decreasing trends in magnesium and calcium concentration with no change in bicarbonate concentration, we inferred that previous inputs of acidic deposition enhanced the rate of rock weathering.