List of Dissertation Abstract
NameSupervisor（Environment and Natural Sciences

Title

Earth and Ecology Course）
Abstract

We surveyed the distribution of alien and native plant species and their functional traits on
the roadside vegetation. We established 362 quadrats, and measured vegetation,
Functional and taxonomic
TokiyoAkira MORIOKIMURA

perspectives for understanding theunderlying mechanisms ofnative and alien plant distributions

environmental and spatial factors, and also collected functional traits data. Our results
indicate that a particular set of alien species, which have high dispersal ability, distribute ina wide range, but range expansion of other alien species is still limited to areas adjacent to
the human settlement. In addition, alien species have relatively superior dispersal andcompetitive abilities to native species. Functional traits could help management to selectalien species, which are specifically of concern, to achieve prevention and termination of alienspecies.
Explaining the factors that structure the variations in biodiversity have been one of the main themes inecology. While studies on this theme for plants have been frequently carried out, those for fungi are lessMichiruAkira MORIKASAHARA

Elucidating the important drivers

conducted. In forest soils, they play an essential role in decomposition of plant litter. The main objective ofof fungal community structures inthis study was to disentangle the effects of spatial variation, environmental variables, and host tree species

leaf litteron fungal decomposer communities. Our study suggests that fungal decomposer community in leaf litter arestructured by biotic/abiotic factors such as host tree species and environmental variables rather thangeographical distances.

Stratigraphy and sedimentary
MisaRyuichi

KOHASE

MAJIMAenvironments at the type locality(Yokohama City) of the Lower
Pleistocene Nojima Formation ofthe Kazusa GroupThe Nojima Formation of the Kazusa Group was first proposed in the strata exposed at the Nojima
Park located at Yokohama City and originally designated as tuffaceous sandstones. As a result of ourdetail geologic survey, the Nojima of the park consists of an upward fining sequence, as muddy
sandstones, sandy mudstones, and mudstones in ascending order. This sequence is estimated to be 100- 300 m in paleo-bathymetry based on molluscan fossils, and to be near the upper boundary of theOlduvai Subchronozone (1.78 Ma) in age based on microfossil and paleomagnetic stratigraphies.

Recently, interest in utilizing ecosystems for disaster risk reduction (DRR) has increased, even though there
remains considerable uncertainty regarding the role of ecosystems. To explore the desired state of anYuta
Akira MORI
KOBAYASHI

The potential role of tree diversity
in reducing shallow landslide risk

ecosystem for DRR, we compared the severity of shallow landslides with tree species richness. We foundthat the predictability of the model, which evaluated relationships between landslide volume andenvironmental variables in watersheds throughout the Japanese Archipelago, increased with tree species
richness. This finding suggests that biodiversity is likely associated with shallow landslide risk reduction,emphasizing a possible reduction of spatial and temporal uncertainty in the roles of woody vegetation.
Microcline is a K-feldspar with composition KAlSi3O8, and is one of the main constituent minerals in theearth’s crust. Microcline nanoscale powders were prepared by zirconia bead mill, and sintering behavior,

Masahiro

Sintering experiment of K-feldspar

grain growth and crystalline. Microcline aggregates are obtained after sintering at 1173-1353K andISHIKAWA

aggregates of nano-sized powders

atomospheric pressure.The effects of sintering temperature and time on the grain growth kinetics ofYuki SATO

microcline aggregates slightly examined. Crystalline of microcline grains decreases significantly by intense
milling with zirconia bead mill, but increases slightly by sintering.

Sell microstructures and growthline analysis of abivalve Lucinoma spectabilis are studied based on the three fossil specimens collected from the ancientchemoautotrophic bivalve
Asuka SEKIRyuichi

Lucinoma spectabilis

MAJIMA(Yokoyama)from the Lower

cold-seep site of the Lower Pleistocene Koshiba Formation exposed at Yokohama City. In the outerlayer of the largest specimen, its late stage has a different shell microstructure from those of the early

Pleistocene Koshiba Formationof the Kazusa Group, Yokohama
City, centred JapanThe shell microstructures and growth line patterns within the radinal sections of chemoautotrophic

and middle stages. The accretionary patterns of growth lines and the distributions of the surface
ornamentations such as concentration ribs evidently suggest that growth rates of the largest specimen
are larger than that of the small and intermediate ones.
Some soil invertebrates such as springtails feed on fungal sporocarps, which produce spores for reproduction.

PreferenceofMorulina

alata Soil invertebrates are thus likely to carry spores to fungal substrates in soil. The possibility of endozoochory

Neanuridae)

for has been studied little for springtail species without molar plates. In Japan, Morulina alata (Neanuridae),Masakazu

Taizo(Collembola:NAKANO

NAKAMORI

fungal sporocarps and effects of gut which lack molar plates, has been observed in sporocarps. This study aimed to elucidate the possibility ofpassage on sporesendozoochory by M. alata. Our results suggest that spore dispersal of some fungus via ingestion by M. alatais possible.

Planktonic foraminifer assemblages of the Olduvai subchronozone are analyzed based on 36 samples in thePaleoenvironmental analysis of the core obtained from the Lower Pleistocene Nojima Formation. I identify 11 genera and 33 species andRyuichi
Yuki MIYAKE
MAJIAM

LowerFormation

Pleistocene

Nojima recognize MIS 74 to MIS 64 based on the fluctuations of the abundance ratios of several characteristic species.

(northernMiura I calculate the first and last occurrence of Globorotalia truncatulinoides and Neogloboquadrina asanoi inPeninsula) based on the planktonic 1.916Ma and 1.828Ma, respectively. I determine the depositional age of the type locality (Nojima Park) offoraminiferal assemblages

the Nojima Formation based on the planktonic foraminifers, paleomagnetic record, and calcareous
nannofossils within 1.828 Ma to 1.67 Ma.
To understand the metabolic activity of epibiotic bacteria on the ventral surface of the galatheid squat lobster

Effect of fixation methods on
Kaori
Ryoji WANIMOTOKI

expression
metatranscriptome

profileanalysis

inof

epibiotic bacteria

Shinkaia crosnieri inhabiting hydrothermal vents of Okinawa Trough, the metatranscriptomes of thesymbionts were analyzed from specimens fixed in situ and after recovery on-board. Results of the analyses
revealed a difference in expression profile between the two fixation methods, most likely due to responses tothe abrupt environmental changes such as depletion of energy sources for chemosynthesis and increase inammonia post-sampling seen in the on-board fixed samples. Furthermore, major energy metabolisms andcarbon fixation pathways of the three main groups of epibionts were shown through mRNA analyses.
In the western part of Sagami Bay, several dominant dinoflagellates such as Ceratium spp. and Noctiluca

Spatio-temporalvariationof scintillans are dominant as representative HAB species. Besides these species, occurrence mechanism ofMegumi

Tomohiko

Dinoflagellate assemblages in the HAB have not well been analyzed. This study focused of the HAB mechanism of the species which have notWADA

KIKUCHInorth-western part of Sagami Bay, been reported as non-HAB species in the field. Optimum water temperature, salinity, nutrients uptake
Japancharacteristics, amount prey, etc. of non-reported HAB species are cleared to differ from the field condition.
and uploaded to our school's website.
Trachycarpus fortunei is an exotic temperate palm introduced to Japan as ornament plants and began to show
significant invasive expansion phenomena generally from 1970s. Ameliorated temperature caused by climatechange and forest fragmentation generated by urbanization have been assumed to have connection with theXiaodai XUAkiko SAKAI

Please fill in here the English title

expansion. I investigated fragmented forests in Kanagawa, to verify differences in palm’s physiologicalcharacteristics, especially the reproduction size and growth rate, along a gradient from urban to mountainarea. Additionally, two species distribution models and landscape index were applied to analyze the effects
of climate change and forest fragmentation on the invasive expansion, respectively, and tried to compare theseeffects of two drivers.