Promenadeカテゴリのエントリ

[Press Release] Fire-derived charcoal might promote fine root decomposition in boreal forests

Boreal forests in Russian Far East are frequently subjected to fire disturbance, which emit large quantities of carbon dioxide (CO2) by burning trees.
An international research group that consists of Assist. Prof. Makoto Kobayashi (Division of Biosphere Science) and researchers of Russian Academy of Sciences provided the first field evidence that fire-derived charcoal may enhance the decomposition of fine larch roots died in sediment. This finding suggests that forest fires can affect CO2 release from boreal forests even after the fires.

This research outcome is published in Soil Biology & Biochemistry.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

[Press Release] Stream resource gradients drive consumption rates of supplemental prey in the adjacent riparian zone

Decades of research have shown that ecosystems are not “stand-alone” entities; instead, ecosystems are linked each other through cross-system movements of materials such as nutrients, detritus, and organisms, which are called spatial subsidies. Aquatic–terrestrial ecosystem linkage is one of the well-known linkage, but less is known about how much effect changes in an aquatic system have on the adjacent terrestrial ecosystem. A research group that includes Assoc. Prof. Junjiro N. Negishi and a Ph.D. student, Nozomi Watanabe (Division of Environmental Science Development) quantified how riverine productivity (donor system) mediates terrestrial food web interactions through spatial subsidies to simplified gravel bar communities. Their results indicated that higher algal biomass in aquatic systems led to increased supplies of emerging aquatic insects. The results also showed that the increased supplies were associated with greater densities of terrestrial consumers and enhanced consumption rates of supplemental in situ prey on gravel bars. This study highlights the potential of donor productivity to drive cascading biotic interactions across coupled ecosystems.

This research outcome is published in Ecosystems.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

Course Feedback Survey Results for the 2016 academic year

Here are the results of feedback surveys about the courses conducted in the 2016 academic year.
・Evaluation and comments (only in Japanese)
・Survey Summary (only in Japanese)

[Press Release] Colored snow in alpine: an ecosystem that algae and bacteria weave

We can see colored snow during the melt season in alpine snowfields. This coloring is known to be due to pigments of snow algae, which can grow even under low temperature. On the other hand, whole microbial community in colored snow have little understanding. A research group that includes Assist. Prof. Mia Terashima, Kazuhiro Umezawa, a Ph.D. student, Assist. Prof. Hisaya Kojima, and Prof. Manabu Fukui (Division of Biosphere Science) analyzed the microbial community of green and red-colored snow containing snow algae from Mount Asahi, Japan. They found that bacteria belonging to the subphylum Betaproteobacteria were frequently detected in both green and red snow. Further results of this paper suggest that the bacteria can utilize the available carbon source in algae-rich environments and may in turn promote algal growth.

This research outcome is published in Frontiers in Microbiology.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

The 3rd Matsuno Environmental Science Award recipients

We are pleased to announce that the following 4 recipients have been selected as recipients of the 3rd Matsuno Environmental Science Award.

Md. Shariful Islam
【Reasons for selection (PDF in Japanese)】
【Abstract】

Ryu Saiki
【Reasons for selection (PDF in Japanese)】
【Abstract】

Venus Leopardas
【Reasons for selection (PDF in Japanese)】
【Abstract】

Sayaka Fujita
【Reasons for selection (PDF in Japanese)】
【Abstract】

Award recipients will be recognized at a ceremony at 3 p.m. on September 29th, at the Graduate School of Environmental Science Homecoming Day event (Please refer to Homecoming Day 2017 for more details). Please join us!

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Graduate School of Environmental Science established the Matsuno Environmental Science Award two years ago. This award recognizes outstanding research conducted by enrolled students, alumni, and alumnae of the Graduate School of Environmental Science.
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[Press Release] Equatorial jet in the lower to middle cloud layer of Venus revealed by Akatsuki

Assoc. Prof. Takeshi Horinouchi and his international research group estimated wind speeds in the Venusian atmosphere by using the 2-μm infrared camera images from the Akatsuki orbiter. They detected winds at low latitude exceeding 80 m/s during July and August 2016. The angular speed around the planetary rotation axis peaks near the equator, and thus they named this wind “equatorial jet”.

This research outcome is published in Nature Geoscience.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

[Press Release] Evidence for ice-ocean albedo feedback in the Arctic Ocean shifting to a seasonal ice zone

Summer sea ice extent in the Arctic Ocean has been reduced by half in the last 40 years. This means that the Arctic Ocean is shifting from perennial to seasonal ice zone where the sea ice disappears in summer. Researchers have focused on several factors that cause this sea ice retreat. A research group that includes Prof. Kay I. Ohshima (Division of Earth System Science) provided quantitative evidence that ice-albedo feedback due to the albedo contrast between water and ice is a major factor in the sea ice retreat.

This research outcome is published in Scientific Reports.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

[Press Release] Reduction in cloud condensation nuclei activity of water-soluble aerosols caused by biogenic emissions in a cool-temperate forest

Biogenic organic aerosols can affect cloud condensation nuclei properties. Researchers, however, are not yet sure of how the difference in the types of terrestrial biogenic sources and the abundance of organics relative to sulfate affect cloud condensation nuclei properties. A research group that includes Astrid Müller, a doctoral student, Assist. Prof. Yuzo Miyazaki (Division of Earth System Science), and Prof. Tsutomu Hiura (Division of Biosphere Science) have investigated water-soluble aerosols for two years in a cool-temperature forest at Tomakomai Experimental Forest, HU (northern Japan). They found evidence that a reduction in cloud condensation nuclei activity of water-soluble aerosols was caused by biogenic emissions from litter/soil microbial activity near the forest floor.

This research outcome is published in Scientific Reports.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

[Press Release] Roots of Japanese house mice: implications for understanding the origin of Japanese

A research group of Prof. Hitoshi Suzuki (Division of Biosphere Science) have long investigated genetic diversity of Japanese house mice (Mus musculus) across Eurasia, including the Japanese archipelago, for over 30 years. Here, by using genetic analyses, his group revealed a long-standing question: when and how the ancient house mice immigrated into Japan. The results of the analyses indicated that the ancient wild populations of the mice immigrated at least twice into Japan in association with prehistoric developments in agricultural techniques by human beings: first from Southern China ca. 4000 years ago and then from the Korean Peninsula ca. 2000 years ago. These two lineages were mixed first in western Japan, then in northern Japan with a delay of about 1,000 years. Furthermore, the results also suggest that another lineage of South Asia-origin might have immigrated into Japan before the two lineage immigrations.

This research outcome is published in Biological Journal of the Linnean Society, a British biological journal.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

[Press Release] Bryophytes as bioindicators of the atmospheric environment in urban-forest landscapes

Prof. Tsutom Hiura (Division of Biosphere Science; Tomakomai Experimental Forest) and Lecturer Yoshitaka Oishi (Fukui Prefectural University) developed an efficient method evaluating the atmospheric environment in urban-forest landscapes by using bryophytes. Bryophytes, which have simple body structures, can respond sensitively to environmental changes, particularly atmospheric environments. In this paper, they showed that measuring concentration and stable isotope ratio of nitrogen in bryophytes enable us to evaluate a level of nitrogen pollution, which is becoming serious in urban areas. In addition, they found that richness of hygrophilic life-forms can reflect the level of drought stress associated with urban heat islands. The combinational use of these bryophyte metrics can contribute to comprehensive understanding of atmospheric environments.

This research outcome is published in Landscape and Urban Planning.

Please visit links below to view the press release (Japanese ver. only).
Research Press Release (PDF)

Graduate School of Environmental Sceince, Hokkaido University