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CBES Class 1A ("Conservation of Wetlands Ecosystem and

Development of Cities"

Seiji Hayashi

Wetlands and Biodiversity

Graduate School of Environmental Studies

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Outline

What is wetland ?

-definition

-classification

-freshwater wetland

-tidal wetland

Tidal wetland and biodiversity

-biology and ecology of intertidal organisms

(mainly benthos,implication for conservation )

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What is wetland ?

So many definitions

Scientific definition

Early U.S. definition (Circular 39)

U.S. Fish and wildlife service definition

Canadian definition

IUCN definition

Legal definition

U.S. National Academy definition

U.S. Army Corps of Engineers definition

Food Security Act definition (Mitch & Gosselink, 2000)

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IUCN definition

Areas of marsh, fen, peatland or water,

whether natural or artificial, permanent or

temporary, with water that is static or

flowing, fresh, brackish, or salt including

areas of marine water, the depth of which at

low tide does not exceed 6 meters.

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Three component basis of a wetland

(Mitch & Gosselink, 2000)

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Classification of freshwater wetland

(Keddy, 2000)

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bog fen

marsh swamphttp://www.wetlandpolicy.ca/wetland-classification-systems/canadian-wetland-classification-system.html

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Simple classification of tidal wetland

Tide-Dominated

Delta

Wave-Dominated

Delta

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(Seybold et al., 2007)

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Tide-dominated delta

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Wave-dominated estuary

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Coastal lagoon

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Tidal flat

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Tidal wetland and biodiversitybiology and ecology of intertidal organisms

(mainly benthos)

*benthos = organisms living on the bottom

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Intertidal zone

Supralittoral zone

Eulittoral (intertidal) zone

Sublittoral (subtidal) zone

Mean high tide

Mean low tide

two high tides and two low tides a day

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Zonation in muddy tidal flat

intertidal subtidal

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Infauna and Epifauna

( )

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Utilization of sea floor

in geologic past

Infaunal life style has been evolved as an anti-predator

strategySea lilies

542M

a

251M

a

65M

a

*Ma=

Mill

ion y

eas a

go

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Infauna as sediment

stabilizer & destabilizer

Sediment

oxidization

Sediment

retention

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Tidal flat as a buffer for

organic matter cycling

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(Castro and Huber, 1992)

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Suspension & Deposit feeding

Key role for organic matter cycling

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Suspension feeder

remove organic particles

from water column

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Suspension

feeding

in clams

Sediments are rejected

as “pseudofeces”

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Deposit feeder

Remove organic particles

from sediments

Oxidize sediments

Fecal mass

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Fecal mass of sandworm

At Chita-Okuda mud flat

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Developmental mode of marine snail

egg

Emerge as crawling juvenile

Planktonic larva

Crawling

juvenile

Direct developer

Disperser

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Batillaria cummingi Batillaria multiformis

Direct developer Disperser

Red-listed in 2 prefectures Red-listed in 8 prefectures

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Disperser vs Direct developer

In disperser, each population is

largely maintained via larval

exchange among neighboring

populations. (larval network)

Direct developer is “self-recruiting”

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Breakup of Larval network

Are disperser more vulnerable under degraded

marine environment?

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For marine reserve design…http://www.piscoweb.org/policy/marine-protected-areas/marine-protected-area-design

http://www.piscoweb.org/publications/outreach-materials/science-of-marine-reserves

Scientifically

designed

MPA

network in

California

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Selected references(housed in NU library)

Keddy P.A. (2000) Wetland ecology : principles andconservation. Cambridge University Press .

Maltby, E. and Barker, T.[eds.] (2009) The wetlandshandbook. Blackwell Publishing.

Mitsch, W.J. and Gosselink, J.G. (2007) Wetlands4th ed. Wiley.