Recent publication
Mehta T.K., Ravi V., Yamasaki S., Lee A. P., Lian M. M., Boon-Hui Tay, Tohari S., Yanai S., Tay
A., Brenner S. and Venkatesh B. (2013) Evidence for at least six Hox clusters in the Japanese
lamprey (Lethenteron japonicum). PNAS (Proceedings of National Academy of Science) 110
(40):16044-16049
Shirakawa H, Yanai S, Goto A. (2013) Lamprey larvae as ecosystem engineers: physical and
geochemical impact on the streambed by their burrowing behavior. Hydrobiologia. 701: 313-322,
2013
Shirakawa H, Yanai S., Goto A. (2012) Spawning redds selection of Arctic lamprey Lethenteron
japonicum in the Ishikari River. Ecol. Civil Eng. 15(1), 71-79
Takayama H., Yanai S. & Shirakawa H. (2011) Evaluation of river restoration techniques using
woody debris and boulders naturally generated from flood events. Ecolo Civil eng. 14: 139-154
Sirakawa . & Yanai S. & Kochi K. (2009) Habitat selection of fluvial lamprey larvae Lethonteron
japonicum change with growth stage. Ecol. Civil Eng. 12:87-98
Yanai S. (2008) Sediment dynamics and characteristics with respect to river disturbance, pp 31-43.
In Ecology of Riparian forests in Japan (Sakio H. & Tamura T. ed.) Springer, Tokyo, Japan..
Marutani T., Kikuchi S., Yanai S. (2008) The light and dark of sabo-dammed Streams in steepland
settings in Japan, pp220-236. In River Futures (Brierley G. & Fryirs A. ed.) Island Press,
Washington, USA.
Kochi K., Sakurai I. and Yanai S. (2007) Role of forest-origin coarse particulate organic matter for
the brackish water amphipod Anisogammarus pugettensis. Bulletin of the Japanese Society of
Fisheries Oceanography
71
255～262
Yanai S., Kochi K. and Ito K. (2006) Effects of chum salmon carcass (Oncorhynchus keta) on forest
and stream ecosystems, in eastern Hokkaido, Japan. Ecology and Civil Engineering 9:167-178.
Sakurai I. and Yanai S.
(2006)
Ecological significance of leaf litter that accumulates in a
river mouth as a feeding spot for young cresthead flounder (Pleuronectes schrenki).
the Japanese Society of Fisheries Oceanography 70
Bulletin of
105～113
K Kochi, S Yanai (2006) Shredder colonization and decomposition of green and senescent leaves
during summer in a headwater stream in northern Japan
.
Ecological Research 21: 544-550
Sediment movement and integrated watershed
management in steep torrential rivers of Hokuriku
region
Tedori River is the largest and one-graded river having an area of 809km2, channel length of 72 km
and gradient of 1/27. The headwater area is Hakusan (elevation 2702m above sea level), which
locates on the border between Ishikawa and Gifu Prefecture. A large scale alluvial fan, which
has an apex at Tsurugi Town, has developed from downstream reach to river mouth. Gravel
mining between 1960 and 1980 were intensively carried out on the reach of alluvial fan. The
flood control dam has built and operated since 1979. After that, significant tree colonization
have been observed including alien invasive locust (Robinia pseudoacasia). After dam
operation, initial fluvial landform change such as bedrock exposition and river bed dropping
have been prominent. This study aims to reveal influence on sediment movement from
mountain to coast and propose a counter measure for river degradation using geomorphological
method or remote sensing method.
Dam building affect fluvial landform: exposed rock on a river bed.
Serious erosion and beech regression occurred in a coastal area
ページの先頭へ
Conservation of endangered fresh water fishes in
Ishikawa Prefecture
Endangere arctic lamprey dwelling in Noto Peninsula
Species and family Freshwater fishes in rivers of Ishikawa Prefecture are amount to 23 families
and 80 species. However, in recent river environmental change and invasion of alien species affect
their natural distribution and habitat. This study conduct to create a database for them by field
investigation and profiling previous work and to evaluate the influence of anthropogenic impact such
as artificial concrete structures and dams on their habitat. Especially we focused on drastic decline
fish such as lamprey and salmonid, to reveal their ecology and propose conservation strategy.
Material flows from forest to the sea through land crab
dwelling in coastal ever green forest in Ishikawa
Prefecture
Land crabs hanging on a tree in a coastal evergreen forest
Land crab Chiromantes haematocheir inhabited in “Kashima shrine forest”
which is one of the most valuable old growth forest in Ishikawa Prefecture.
Land crabs have a unique life history that adult spend most of life in the forest and migrate to release
larvae to beach on summer full moon night. The released larvae travel from river mouth to the sea
and return to forest after one month. We made research on their feeding and breeding ecology, they
play a very important role but on the material flow from the forest to the sea also fish production in
an estuary ecosystem. We try to restore the past distributional area and reveal the reason for drastic
decline of their population.
Factors affecting crop damage by wild boar and
develop a landscape ecological method for retarding
damage in a wild boar prone area
A wild boar bathing muddy water in an abandoned paddy field
Crop damages by wild boar and deer have drastically increased within this decade in Ishikawa
Prefecture and counter measure should be taken immediately. We firstly try to extract the
characteristics of damage prone area by analyzing temporal change for the past damage area using
Geographical Information System. We also collect information on environmental variables such as
land utilization, vegetation type and form of agricultural management. We perform statistical
analysis to extract crucial factor for crop damage and damage prediction is carried out by Maxent
model. Field investigation such as interview for farmers and foot print trace are also conducted. We
propose a new forest and agricultural management method for retarding wildlife damage based on
landscape ecological technique.