List of Dissertation Abstract （Environment and Natural Sciences Earth and Ecology Course）
NameSupervisor

Title
Seasonal and year-to-year

YusukeShinji

IKAWASHIMODE

variations in the surface copepodid
population and egg production rateof two species of Eucalanidae in
Sagami Bay, JapanAbstract
In this study, we investigated the relationship between length of surface occurrence period of Eucalanus
californicus and Eucalanus hyalinus and surface environment, and egg production rate (EPR) experiments
were also conducted. We conducted monthly zooplankton samplings for four years from 2013 to 2016 in
Sagami Bay, Japan. From the result of surface occurrence period and analysis of spawning strategy, it wassuggested that the appearance pattern of both species and the EPR may differ. It is considered that thesedifferences reflect the difference in the environments of the two distributed areas.

The ontogengetic trajectories of septal spacings in phyllocerastids (Hypophylloceras subramosum andTetsuro
Ryoji WANIIWASAKI

Morphological anarysis ofPhyllpachyceras ezoense) that occurred from the Yezo Group in the northwestern Hokkaido were analyzed.
Late Cretaceous
H. subramosum were classified into three types. The abundances of three types change from bottom to top ofphyllocerastids from the Yezo
the stratigraphic horizons. P. ezoense were classified into two types. These two types were possibly sexual
Group, northwestern Hokkaido
dimorphism.

ShinjiKana OTAKASHIMODE

Seasonal fluctuation and bodycolor change of planktonic
copepod Sapphirinidae in thenorth-western part of Sagami
Bay, Japan

The purpose of this study was to clarify the emergence trend of Sapphirinidae and to reevaluate the bodycolor change of adult males in Sagami Bay. Our result suggested that the time of appearance varies dependingon genus and seasonally flowing into the Sagami bay. Sapphirina nigromaculata was not affected by light
conditions, and the body color change was found to be controlled by circadian rhythm.

Topographic complexity affects various environments and plants had evolved their traits for advancing intoNanami
Akiko SAKAI
KONDO

Phylogenetic relationshipbetween topographical niche
selection and traits
in Japanese Acer

their current topographic position, topographic niche. In this study, the phylogenetic relationship between
topographical niche selection and traits was examined. As a result, species inhabit concave grounds withlarger Trunk Inclination, which would response to disturbances. Also, effective light capture prioritize inshaded condition and height growth in light condition. Finally, Leaf C/N would change along various
environment mediated topography and radiate even within closely related species.
We investigated compressional (Vp) and shear (Vs) wave velocities in lawsonite blueschist to evaluate theeffect of dehydration reaction on Vp/Vs ratio under the condition of lawsonite dehydration.

HayataMasahiro

SAKURAGIISHIKAWA

Elastic wave velocity change
caused lawsonite
decomposition in blueschist atVp and Vs markedly dropped over 350℃ during temperature ramping while Vp/Vs ratio stayed constant.

1.0GPa and up to 550℃

For the reason of constant Vp/Vs ratio, many pores were in the breaking lawsonite and near anorthite, andAfter the experiment, 11.3 vol.% of lawsonite contained in the sample broke down and formed anorthite
newly.

we inferred that released H2O was trapped in these pores. So dehydration reaction proceeded without Vp/Vs
ratio changes.
Bryophytes grow on various substrates such as soil, rock, and trunk that differ according to the species. WeTakayuki
Akiko SAKAISUGIMOTO

The relation between growth
substrate and phylogenetic
group of bryophyte

investigated relations to the species composition of bryophytes, growth substrates, environmental gradientsand phylogenetic groups. As a result, the species composition strongly correlated with growth substrates, andwas affected by the forest area around the surveyed area as one of the environmental gradient. Whereas, inthe phylogenetic study, the morphological characteristics tended to be preserved rather than the growth
substrates.

Yusuke
Akira MORITAKAGI

Biodiversity and ecosystem
multifunctionality relationshipin natural plant communities:
with a context of climatechange

I suggested that plant species richness can contribute to maintain ecosystem multifunctionality through theeffect of high-performance plant species even under climate change.

I focused on the roles of root necromass in post-fire recovery processes of soil and vegetation. Even after theMizuki
Akira MORI
MAEDA

The roles of root necromass in high intensity wildfire, the root necromass remained on soil surface layer. Moreover, the root necromass was
post-fire recovery processes of associated with the increment of soil microbial biomass and vegetation coverage directly or indirectly. Hence,
it was suggested that the occasional addition of root necromass derived from the forest fire played ansoil and vegetation
important role as a driving element for post-fire recovery of soil and vegetation.