A5080002724- Arctic and Antarctic ice dynamics
- Hymenoptera taxonomy and phylogeny
- Plant and animal studies
- Cryospheric studies and observations
- Insect-Plant Interactions and Control
- Climate change and permafrost
- Oceanographic and Atmospheric Processes
- Methane Hydrates and Related Phenomena
- Fossil Insects in Amber
- Ocean Acidification Effects and Responses
- Chemistry and Chemical Engineering
- Effects and risks of endocrine disrupting chemicals
- Polar Research and Ecology
- Pharmaceutical and Antibiotic Environmental Impacts
- Winter Sports Injuries and Performance
- Marine and coastal ecosystems
- Insect and Arachnid Ecology and Behavior
- Combustion and Detonation Processes
- Ocean Waves and Remote Sensing
- Microbial bioremediation and biosurfactants
- Diatoms and Algae Research
- Species Distribution and Climate Change
- Biocrusts and Microbial Ecology
- Cell Image Analysis Techniques
- Indigenous Studies and Ecology
National Institute of Polar Research
2021-2025
Japan Agency for Marine-Earth Science and Technology
2020-2022
Hokkaido University
2015-2021
Kobe University
2014-2020
Japan Society for the Promotion of Science
2016-2017
Soka University
2015
Prefectural University of Kumamoto
2011
Nagasaki University
2002
The genus Ishigakia is reported from Vietnam for the first time, and two new species (I. babeensis sp. nov. I. duongi nov.) are described Northeast using morphological genetic data. These also inserted in key to world of provided by Ito Maeto (2016).
Taxon sampling is a central aspect of phylogenetic study design, but it has received limited attention in the context total-evidence dating, widely used dating approach that directly integrates molecular and morphological information from extant fossil taxa. We here assess impact commonly employed outgroup schemes missing data taxa on age estimates analysis under uniform tree prior. Our group Pimpliformes, highly diverse, rapidly radiating parasitoid wasps family Ichneumonidae. analyze set...
Ten Japanese species of the genus Spilopteron Townes, 1965 are recognized. Five new species, S. albiventre sp. nov., brachyurum nigrum oblongulum nov. and pseudonigrum described from Japan. Morphological discrimination between most is confirmed by sequence analysis mitochondrial COI gene, which indicates following relationships: + apicale (Matsumura, 1912), tosaense (Uchida, 1934) luteum 1930). A key to provided. This seems have its center diversity in mid-latitude area East Asia.
Abstract Arctic sea ice incorporates and transports sediment, releasing it back into the water column during melting season. This process constitutes an important aspect of marine sediment transport biogeochemical cycling. Sediment incorporation is considered to occur mainly through underwater interaction between frazil resuspended referred as suspension freezing. However, harsh environmental conditions have greatly limited field observations this phenomenon. Analysis mooring data from a...
Antarctic Bottom Water (AABW) occupies the abyssal layer of world ocean and contributes to global overturning circulation. It originates from dense shelf water, which forms brine rejection during sea ice production. An important region AABW formation has been identified off Cape Darnley polynya. However, it remains unclear why how high production leads formation. Using moored acoustic measurements a satellite microwave algorithm, we reveal that underwater frazil dominates in This prevents...
Abstract The coastal polynya formed off Cape Darnley, in the Southern Ocean, is a favorable site for secondary phytoplankton bloom late summer and autumn. In February of 2018, we conducted in‐situ observations onboard an icebreaker measured surface water chlorophyll concentrations reaching 5.5 μg/L. Concurrently, turbulent conditions associated with wind speeds exceeding 20 m/s, ocher‐colored newly‐formed sea ice, form grease pancake spread across polynya. Chlorophyll ice were 47 times...
In the Sea of Okhotsk, sediment incorporation, transport and release by sea ice potentially plays important roles in bio-related material (such as iron) cycle ecosystem. The backscatter strength data bottom-mounted Acoustic Doppler Current Profilers have suggested signals frazil down to 30 m depth, upward throughout water column simultaneously region northeast Sakhalin, with a depth ∼100 m. Such events occurred under turbulent conditions strong winds 10–20 s−1. During such events, newly...
The detection of thin-ice thickness using satellite microwave radiometers is a strong tool for estimating sea-ice production in coastal polynyas, which leads to dense water formation driving ocean thermohaline circulation. Thin-ice areas are classified into two ice types: active frazil, comprising frazil and open water, thin solid ice, relatively uniform ice. A algorithm AMSR-E has been developed classify these types estimate <20 cm. In this study, we validate the applicability successor,...
Sponge-like bicontinuous morphologies (see Figure and also cover) are ubiquitous in the physical biological sciences, but only qualitatively understood terms of their structure. Here, 3D imaging techniques used to explore characteristics such at nanoscale, microscale, macroscale. Comparison local global topology metrics provides quantitative evidence similarities between these morphologies.
Abstract Formation of supercooled water and frazil ice was studied in the Chukchi Sea coastal polynya off Barrow, Alaska, USA, winter 2009/10, using moored salinity/temperature sensors Ice Profiling Sonar (IPS) data along with satellite data. Oceanographic from two moorings revealed episodic events potential supercooling at 30–40m depth, including possibility situ supercooling, while open. We identified ice-like signals IPS down to 5–15 m associated large heat loss windy, turbulent...
Abstract The lowest latitude sea ice in the world (excluding coastal freezing) is southern Sea of Okhotsk (south 46°N), where it has significant impacts on freshwater input and primary production. This region subject to climate change, accordingly monitoring conditions important. However, interannual variability region's poorly understood due its logistical challenges. observations have been conducted this every winter for period 1996–2020. likely factors responsible were investigated using...
Phytoplankton communities in seasonally ice-covered areas are largely affected by ice algae. The Okhotsk Sea is the southernmost sea zone northern hemisphere with a sizeable seasonal cover, thus algae of have large potential to seed early spring bloom. Little known about algal and their seeding effects. We investigated dynamics composition photophysiological performances an community 6-day laboratory incubation experiment that simulated natural melt conditions. Centric diatoms, especially...
Abstract Basal melting of ice shelves is considered to be the principal driver recent mass loss in Antarctica. Nevertheless, in-situ oceanic data covering extensive areas a subshelf cavity are sparse. Here we show comprehensive structures temperature, salinity and current measured January 2018 through four boreholes drilled at ~3-km-long shelf Langhovde Glacier East The measurements were performed 302–12 m-thick ocean beneath 234–412 shelf. indicate that Modified Warm Deep Water transported...
The delimitation of two ichneumonid species, Spilopteron apicale (Matsumura) and S. tosaense (Uchida), was investigated using DNA sequences the mitochondrial COI nuclear 28S rRNA genes, as well adult morphology.The species have long been confused were until recently speculated to be same with continuous colour variation.Our molecular morphological studies reveal that there are distinct species: a dark confined northern or high latitude localities (S. apicale) widely distributed marked...
Abstract We elucidated the effects of snow and remineralization processes on nutrient distributions in multi‐year landfast sea ice (fast ice) Lützow‐Holm Bay, East Antarctica. Based sea‐ice salinity, oxygen isotopic ratios, thin section analyses, we found that fast grew upward due to year‐by‐year accumulation snow. Compared seawater origin, concentrations shallow were low replacement by clean fresh In deeper origin (the lower half column), was dominated degradation organic matter. By...
The Japanese species of the genus Therion Curtis, 1829 (Ichneumonidae: Anomaloninae) were revised based on examination 447 specimens. Four are recognized morphology and sequence data (mtCOI). Two them identified as previously known species: T . circumflexum (Linnaeus, 1758) giganteum (Gravenhorst, 1829). other two described new: carinatum Shimizu & Bennett, sp. nov. nigrigasterum Shimizu, Bennett Ito, In addition, T. rufomaculatum (Uchida, 1928) stat. rev. is once again synonymized with...